iceberg/spec/

table_metadata.rs

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// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

//! Defines the [table metadata](https://iceberg.apache.org/spec/#table-metadata).
//! The main struct here is [TableMetadataV2] which defines the data for a table.

use std::cmp::Ordering;
use std::collections::HashMap;
use std::fmt::{Display, Formatter};
use std::hash::Hash;
use std::sync::Arc;

use _serde::TableMetadataEnum;
use chrono::{DateTime, Utc};
use serde::{Deserialize, Serialize};
use serde_repr::{Deserialize_repr, Serialize_repr};
use uuid::Uuid;

use super::snapshot::SnapshotReference;
pub use super::table_metadata_builder::{TableMetadataBuildResult, TableMetadataBuilder};
use super::{
    DEFAULT_PARTITION_SPEC_ID, PartitionSpecRef, PartitionStatisticsFile, Schema, SchemaId,
    SchemaRef, SnapshotRef, SnapshotRetention, SortOrder, SortOrderRef, StatisticsFile, StructType,
    TableProperties, Transform,
};
use crate::catalog::{METADATA_FOLDER_NAME, MetadataLocation};
use crate::compression::CompressionCodec;
use crate::error::{Result, invalid_data, timestamp_ms_to_utc};
use crate::io::FileIO;
use crate::partitioning::compute_unified_partition_type;
use crate::spec::EncryptedKey;
use crate::{Error, ErrorKind};

static MAIN_BRANCH: &str = "main";
pub(crate) static ONE_MINUTE_MS: i64 = 60_000;

/// Sentinel value used by the Java implementation and older metadata files
/// to represent a missing/empty current snapshot ID. During deserialization,
/// this value is normalized to `None`.
pub(crate) static EMPTY_SNAPSHOT_ID: i64 = -1;
pub(crate) static INITIAL_SEQUENCE_NUMBER: i64 = 0;

/// Initial row id for row lineage for new v3 tables and older tables upgrading to v3.
pub const INITIAL_ROW_ID: u64 = 0;
/// Minimum format version that supports row lineage (v3).
pub const MIN_FORMAT_VERSION_ROW_LINEAGE: FormatVersion = FormatVersion::V3;
/// Reference to [`TableMetadata`].
pub type TableMetadataRef = Arc<TableMetadata>;

#[derive(Debug, PartialEq, Deserialize, Eq, Clone)]
#[serde(try_from = "TableMetadataEnum")]
/// Fields for the version 2 of the table metadata.
///
/// We assume that this data structure is always valid, so we will panic when invalid error happens.
/// We check the validity of this data structure when constructing.
pub struct TableMetadata {
    /// Integer Version for the format.
    pub(crate) format_version: FormatVersion,
    /// A UUID that identifies the table
    pub(crate) table_uuid: Uuid,
    /// Location tables base location
    pub(crate) location: String,
    /// The tables highest sequence number
    pub(crate) last_sequence_number: i64,
    /// Timestamp in milliseconds from the unix epoch when the table was last updated.
    pub(crate) last_updated_ms: i64,
    /// An integer; the highest assigned column ID for the table.
    pub(crate) last_column_id: i32,
    /// A list of schemas, stored as objects with schema-id.
    pub(crate) schemas: HashMap<i32, SchemaRef>,
    /// ID of the table’s current schema.
    pub(crate) current_schema_id: i32,
    /// A list of partition specs, stored as full partition spec objects.
    pub(crate) partition_specs: HashMap<i32, PartitionSpecRef>,
    /// ID of the “current” spec that writers should use by default.
    pub(crate) default_spec: PartitionSpecRef,
    /// Partition type of the default partition spec.
    pub(crate) default_partition_type: StructType,
    /// An integer; the highest assigned partition field ID across all partition specs for the table.
    pub(crate) last_partition_id: i32,
    ///A string to string map of table properties. This is used to control settings that
    /// affect reading and writing and is not intended to be used for arbitrary metadata.
    /// For example, commit.retry.num-retries is used to control the number of commit retries.
    pub(crate) properties: HashMap<String, String>,
    /// long ID of the current table snapshot; must be the same as the current
    /// ID of the main branch in refs.
    pub(crate) current_snapshot_id: Option<i64>,
    ///A list of valid snapshots. Valid snapshots are snapshots for which all
    /// data files exist in the file system. A data file must not be deleted
    /// from the file system until the last snapshot in which it was listed is
    /// garbage collected.
    pub(crate) snapshots: HashMap<i64, SnapshotRef>,
    /// A list (optional) of timestamp and snapshot ID pairs that encodes changes
    /// to the current snapshot for the table. Each time the current-snapshot-id
    /// is changed, a new entry should be added with the last-updated-ms
    /// and the new current-snapshot-id. When snapshots are expired from
    /// the list of valid snapshots, all entries before a snapshot that has
    /// expired should be removed.
    pub(crate) snapshot_log: Vec<SnapshotLog>,

    /// A list (optional) of timestamp and metadata file location pairs
    /// that encodes changes to the previous metadata files for the table.
    /// Each time a new metadata file is created, a new entry of the
    /// previous metadata file location should be added to the list.
    /// Tables can be configured to remove the oldest metadata log entries and
    /// keep a fixed-size log of the most recent entries after a commit.
    pub(crate) metadata_log: Vec<MetadataLog>,

    /// A list of sort orders, stored as full sort order objects.
    pub(crate) sort_orders: HashMap<i64, SortOrderRef>,
    /// Default sort order id of the table. Note that this could be used by
    /// writers, but is not used when reading because reads use the specs
    /// stored in manifest files.
    pub(crate) default_sort_order_id: i64,
    /// A map of snapshot references. The map keys are the unique snapshot reference
    /// names in the table, and the map values are snapshot reference objects.
    /// There is always a main branch reference pointing to the current-snapshot-id
    /// even if the refs map is null.
    pub(crate) refs: HashMap<String, SnapshotReference>,
    /// Mapping of snapshot ids to statistics files.
    pub(crate) statistics: HashMap<i64, StatisticsFile>,
    /// Mapping of snapshot ids to partition statistics files.
    pub(crate) partition_statistics: HashMap<i64, PartitionStatisticsFile>,
    /// Encryption Keys - map of key id to the actual key
    pub(crate) encryption_keys: HashMap<String, EncryptedKey>,
    /// Next row id to be assigned for Row Lineage (v3)
    pub(crate) next_row_id: u64,
}

impl TableMetadata {
    /// Convert this Table Metadata into a builder for modification.
    ///
    /// `current_file_location` is the location where the current version
    /// of the metadata file is stored. This is used to update the metadata log.
    /// If `current_file_location` is `None`, the metadata log will not be updated.
    /// This should only be used to stage-create tables.
    #[must_use]
    pub fn into_builder(self, current_file_location: Option<String>) -> TableMetadataBuilder {
        TableMetadataBuilder::new_from_metadata(self, current_file_location)
    }

    /// Check if a partition field name exists in any partition spec.
    #[inline]
    pub(crate) fn partition_name_exists(&self, name: &str) -> bool {
        self.partition_specs
            .values()
            .any(|spec| spec.fields().iter().any(|pf| pf.name == name))
    }

    /// Check if a field name exists in any schema.
    #[inline]
    pub(crate) fn name_exists_in_any_schema(&self, name: &str) -> bool {
        self.schemas
            .values()
            .any(|schema| schema.field_by_name(name).is_some())
    }

    /// Returns format version of this metadata.
    #[inline]
    pub fn format_version(&self) -> FormatVersion {
        self.format_version
    }

    /// Returns uuid of current table.
    #[inline]
    pub fn uuid(&self) -> Uuid {
        self.table_uuid
    }

    /// Returns table location.
    #[inline]
    pub fn location(&self) -> &str {
        self.location.as_str()
    }

    /// Returns last sequence number.
    #[inline]
    pub fn last_sequence_number(&self) -> i64 {
        self.last_sequence_number
    }

    /// Returns the next sequence number for the table.
    ///
    /// For format version 1, it always returns the initial sequence number.
    /// For other versions, it returns the last sequence number incremented by 1.
    #[inline]
    pub fn next_sequence_number(&self) -> i64 {
        match self.format_version {
            FormatVersion::V1 => INITIAL_SEQUENCE_NUMBER,
            _ => self.last_sequence_number + 1,
        }
    }

    /// Returns the last column id.
    #[inline]
    pub fn last_column_id(&self) -> i32 {
        self.last_column_id
    }

    /// Returns the last partition_id
    #[inline]
    pub fn last_partition_id(&self) -> i32 {
        self.last_partition_id
    }

    /// Returns last updated time.
    #[inline]
    pub fn last_updated_timestamp(&self) -> Result<DateTime<Utc>> {
        timestamp_ms_to_utc(self.last_updated_ms)
    }

    /// Returns last updated time in milliseconds.
    #[inline]
    pub fn last_updated_ms(&self) -> i64 {
        self.last_updated_ms
    }

    /// Returns schemas
    #[inline]
    pub fn schemas_iter(&self) -> impl ExactSizeIterator<Item = &SchemaRef> {
        self.schemas.values()
    }

    /// Lookup schema by id.
    #[inline]
    pub fn schema_by_id(&self, schema_id: SchemaId) -> Option<&SchemaRef> {
        self.schemas.get(&schema_id)
    }

    /// Get current schema
    #[inline]
    pub fn current_schema(&self) -> &SchemaRef {
        self.schema_by_id(self.current_schema_id)
            .expect("Current schema id set, but not found in table metadata")
    }

    /// Get the id of the current schema
    #[inline]
    pub fn current_schema_id(&self) -> SchemaId {
        self.current_schema_id
    }

    /// Returns all partition specs.
    #[inline]
    pub fn partition_specs_iter(&self) -> impl ExactSizeIterator<Item = &PartitionSpecRef> {
        self.partition_specs.values()
    }

    /// Lookup partition spec by id.
    #[inline]
    pub fn partition_spec_by_id(&self, spec_id: i32) -> Option<&PartitionSpecRef> {
        self.partition_specs.get(&spec_id)
    }

    /// Get default partition spec
    #[inline]
    pub fn default_partition_spec(&self) -> &PartitionSpecRef {
        &self.default_spec
    }

    /// Return the partition type of the default partition spec.
    #[inline]
    pub fn default_partition_type(&self) -> &StructType {
        &self.default_partition_type
    }

    /// Returns the unified partition type across every partition spec in the table, resolved
    /// against `schema`.
    ///
    /// Unlike [`Self::default_partition_type`], the result contains all partition fields ever
    /// used by the table, so partition values stay readable across partition spec evolution.
    /// See [`compute_unified_partition_type`] for the exact merge rules.
    pub fn unified_partition_type(&self, schema: &Schema) -> Result<StructType> {
        compute_unified_partition_type(
            self.partition_specs_iter().map(|spec| spec.as_ref()),
            schema,
        )
    }

    #[inline]
    /// Returns spec id of the "current" partition spec.
    pub fn default_partition_spec_id(&self) -> i32 {
        self.default_spec.spec_id()
    }

    /// Returns all snapshots
    #[inline]
    pub fn snapshots(&self) -> impl ExactSizeIterator<Item = &SnapshotRef> {
        self.snapshots.values()
    }

    /// Lookup snapshot by id.
    #[inline]
    pub fn snapshot_by_id(&self, snapshot_id: i64) -> Option<&SnapshotRef> {
        self.snapshots.get(&snapshot_id)
    }

    /// Returns snapshot history.
    #[inline]
    pub fn history(&self) -> &[SnapshotLog] {
        &self.snapshot_log
    }

    /// Returns the metadata log.
    #[inline]
    pub fn metadata_log(&self) -> &[MetadataLog] {
        &self.metadata_log
    }

    /// Get current snapshot
    #[inline]
    pub fn current_snapshot(&self) -> Option<&SnapshotRef> {
        self.current_snapshot_id.map(|s| {
            self.snapshot_by_id(s)
                .expect("Current snapshot id has been set, but doesn't exist in metadata")
        })
    }

    /// Get the current snapshot id
    #[inline]
    pub fn current_snapshot_id(&self) -> Option<i64> {
        self.current_snapshot_id
    }

    /// Get the snapshot for a reference
    /// Returns an option if the `ref_name` is not found
    #[inline]
    pub fn snapshot_for_ref(&self, ref_name: &str) -> Option<&SnapshotRef> {
        self.refs.get(ref_name).map(|r| {
            self.snapshot_by_id(r.snapshot_id)
                .unwrap_or_else(|| panic!("Snapshot id of ref {ref_name} doesn't exist"))
        })
    }

    /// Return all sort orders.
    #[inline]
    pub fn sort_orders_iter(&self) -> impl ExactSizeIterator<Item = &SortOrderRef> {
        self.sort_orders.values()
    }

    /// Lookup sort order by id.
    #[inline]
    pub fn sort_order_by_id(&self, sort_order_id: i64) -> Option<&SortOrderRef> {
        self.sort_orders.get(&sort_order_id)
    }

    /// Returns default sort order id.
    #[inline]
    pub fn default_sort_order(&self) -> &SortOrderRef {
        self.sort_orders
            .get(&self.default_sort_order_id)
            .expect("Default order id has been set, but not found in table metadata!")
    }

    /// Returns default sort order id.
    #[inline]
    pub fn default_sort_order_id(&self) -> i64 {
        self.default_sort_order_id
    }

    /// Returns properties of table.
    #[inline]
    pub fn properties(&self) -> &HashMap<String, String> {
        &self.properties
    }

    /// Returns the base location for metadata files (manifests, manifest lists).
    ///
    /// Honors the `write.metadata.path` table property when set, otherwise defaults
    /// to the `metadata` subdirectory under the table location.
    pub fn metadata_location(&self) -> Result<String> {
        Ok(self
            .table_properties()
            .write_metadata_path()?
            .unwrap_or_else(|| format!("{}/{}", self.location(), METADATA_FOLDER_NAME)))
    }

    /// Returns the metadata compression codec from table properties.
    ///
    /// Returns `CompressionCodec::None` if compression is disabled or not configured.
    /// Returns `CompressionCodec::Gzip` if gzip compression is enabled.
    ///
    /// # Errors
    ///
    /// Returns an error if the compression codec property has an invalid value.
    pub fn metadata_compression_codec(&self) -> Result<CompressionCodec> {
        self.table_properties().metadata_compression_codec()
    }

    /// Returns a typed view that parses each table property when its getter is called.
    #[inline]
    pub fn table_properties(&self) -> TableProperties<'_> {
        TableProperties::new(&self.properties)
    }

    /// Return location of statistics files.
    #[inline]
    pub fn statistics_iter(&self) -> impl ExactSizeIterator<Item = &StatisticsFile> {
        self.statistics.values()
    }

    /// Return location of partition statistics files.
    #[inline]
    pub fn partition_statistics_iter(
        &self,
    ) -> impl ExactSizeIterator<Item = &PartitionStatisticsFile> {
        self.partition_statistics.values()
    }

    /// Get a statistics file for a snapshot id.
    #[inline]
    pub fn statistics_for_snapshot(&self, snapshot_id: i64) -> Option<&StatisticsFile> {
        self.statistics.get(&snapshot_id)
    }

    /// Get a partition statistics file for a snapshot id.
    #[inline]
    pub fn partition_statistics_for_snapshot(
        &self,
        snapshot_id: i64,
    ) -> Option<&PartitionStatisticsFile> {
        self.partition_statistics.get(&snapshot_id)
    }

    fn construct_refs(&mut self) {
        if let Some(current_snapshot_id) = self.current_snapshot_id
            && !self.refs.contains_key(MAIN_BRANCH)
        {
            self.refs
                .insert(MAIN_BRANCH.to_string(), SnapshotReference {
                    snapshot_id: current_snapshot_id,
                    retention: SnapshotRetention::Branch {
                        min_snapshots_to_keep: None,
                        max_snapshot_age_ms: None,
                        max_ref_age_ms: None,
                    },
                });
        }
    }

    /// Iterate over all encryption keys
    #[inline]
    pub fn encryption_keys_iter(&self) -> impl ExactSizeIterator<Item = &EncryptedKey> {
        self.encryption_keys.values()
    }

    /// Get the encryption key for a given key id
    #[inline]
    pub fn encryption_key(&self, key_id: &str) -> Option<&EncryptedKey> {
        self.encryption_keys.get(key_id)
    }

    /// Get the next row id to be assigned
    #[inline]
    pub fn next_row_id(&self) -> u64 {
        self.next_row_id
    }

    /// Read table metadata from the given location.
    pub async fn read_from(
        file_io: &FileIO,
        metadata_location: impl AsRef<str>,
    ) -> Result<TableMetadata> {
        let metadata_location = metadata_location.as_ref();
        let input_file = file_io.new_input(metadata_location)?;
        let metadata_content = input_file.read().await?;

        // Check if the file is compressed by looking for the gzip "magic number".
        let metadata = if metadata_content.len() > 2
            && metadata_content[0] == 0x1F
            && metadata_content[1] == 0x8B
        {
            let decompressed_data = CompressionCodec::gzip_default()
                .decompress(metadata_content.to_vec())
                .map_err(|e| {
                    invalid_data!("Trying to read compressed metadata file")
                        .with_context("file_path", metadata_location)
                        .with_source(e)
                })?;
            serde_json::from_slice(&decompressed_data)?
        } else {
            serde_json::from_slice(&metadata_content)?
        };

        Ok(metadata)
    }

    /// Write table metadata to the given location.
    pub async fn write_to(
        &self,
        file_io: &FileIO,
        metadata_location: &MetadataLocation,
    ) -> Result<()> {
        let json_data = serde_json::to_vec(self)?;

        // Check if compression codec from properties matches the one in metadata_location
        let codec = self.table_properties().metadata_compression_codec()?;

        if codec != metadata_location.compression_codec() {
            return Err(invalid_data!(
                "Compression codec mismatch: metadata_location has {:?}, but table properties specify {:?}",
                metadata_location.compression_codec(),
                codec
            ));
        }

        // Apply compression based on codec
        let data_to_write = match codec {
            CompressionCodec::Gzip(_) => codec.compress(json_data)?,
            CompressionCodec::None => json_data,
            _ => {
                return Err(invalid_data!(
                    "Unsupported metadata compression codec: {codec:?}"
                ));
            }
        };

        file_io
            .new_output(metadata_location.to_string())?
            .write(data_to_write.into())
            .await
    }

    /// Normalize this partition spec.
    ///
    /// This is an internal method
    /// meant to be called after constructing table metadata from untrusted sources.
    /// We run this method after json deserialization.
    /// All constructors for `TableMetadata` which are part of `iceberg-rust`
    /// should return normalized `TableMetadata`.
    pub(super) fn try_normalize(&mut self) -> Result<&mut Self> {
        self.validate_current_schema()?;
        self.normalize_current_snapshot()?;
        self.construct_refs();
        self.validate_refs()?;
        self.validate_chronological_snapshot_logs()?;
        self.validate_chronological_metadata_logs()?;
        // Normalize location (remove trailing slash)
        self.location = self.location.trim_end_matches('/').to_string();
        self.validate_snapshot_sequence_number()?;
        self.validate_schema_format_compatibility()?;
        self.try_normalize_partition_spec()?;
        self.try_normalize_sort_order()?;
        Ok(self)
    }

    /// Validate active default-spec sources and add the spec if it is not present.
    fn try_normalize_partition_spec(&mut self) -> Result<()> {
        for field in self.default_spec.fields() {
            // Historical specs may reference dropped columns, but active default-spec
            // fields need a source for new writes. Void fields do not read their source.
            if field.transform != Transform::Void
                && self.current_schema().field_by_id(field.source_id).is_none()
            {
                return Err(invalid_data!(
                    "Default partition spec {} references missing source field {} in current schema {}",
                    self.default_spec.spec_id(),
                    field.source_id,
                    self.current_schema_id
                ));
            }
        }

        if self
            .partition_spec_by_id(self.default_spec.spec_id())
            .is_none()
        {
            self.partition_specs.insert(
                self.default_spec.spec_id(),
                Arc::new(Arc::unwrap_or_clone(self.default_spec.clone())),
            );
        }

        Ok(())
    }

    /// If the default sort order is unsorted but the sort order is not present, add it
    fn try_normalize_sort_order(&mut self) -> Result<()> {
        // Validate that sort order ID 0 (reserved for unsorted) has no fields
        if let Some(sort_order) = self.sort_order_by_id(SortOrder::UNSORTED_ORDER_ID)
            && !sort_order.fields.is_empty()
        {
            return Err(Error::new(
                ErrorKind::Unexpected,
                format!(
                    "Sort order ID {} is reserved for unsorted order",
                    SortOrder::UNSORTED_ORDER_ID
                ),
            ));
        }

        if self.sort_order_by_id(self.default_sort_order_id).is_some() {
            return Ok(());
        }

        if self.default_sort_order_id != SortOrder::UNSORTED_ORDER_ID {
            return Err(invalid_data!(
                "No sort order exists with the default sort order id {}.",
                self.default_sort_order_id
            ));
        }

        let sort_order = SortOrder::unsorted_order();
        self.sort_orders
            .insert(SortOrder::UNSORTED_ORDER_ID, Arc::new(sort_order));
        Ok(())
    }

    /// Validate the current schema is set and exists.
    fn validate_current_schema(&self) -> Result<()> {
        if self.schema_by_id(self.current_schema_id).is_none() {
            return Err(invalid_data!(
                "No schema exists with the current schema id {}.",
                self.current_schema_id
            ));
        }
        Ok(())
    }

    /// If current snapshot is Some(-1) then set it to None.
    fn normalize_current_snapshot(&mut self) -> Result<()> {
        if let Some(current_snapshot_id) = self.current_snapshot_id {
            if current_snapshot_id == EMPTY_SNAPSHOT_ID {
                self.current_snapshot_id = None;
            } else if self.snapshot_by_id(current_snapshot_id).is_none() {
                return Err(invalid_data!(
                    "Snapshot for current snapshot id {current_snapshot_id} does not exist in the existing snapshots list"
                ));
            }
        }
        Ok(())
    }

    /// Validate that all refs are valid (snapshot exists)
    fn validate_refs(&self) -> Result<()> {
        for (name, snapshot_ref) in self.refs.iter() {
            if self.snapshot_by_id(snapshot_ref.snapshot_id).is_none() {
                return Err(invalid_data!(
                    "Snapshot for reference {name} does not exist in the existing snapshots list"
                ));
            }
        }

        let main_ref = self.refs.get(MAIN_BRANCH);
        if self.current_snapshot_id.is_some() {
            if let Some(main_ref) = main_ref
                && main_ref.snapshot_id != self.current_snapshot_id.unwrap_or_default()
            {
                return Err(invalid_data!(
                    "Current snapshot id does not match main branch ({:?} != {:?})",
                    self.current_snapshot_id.unwrap_or_default(),
                    main_ref.snapshot_id
                ));
            }
        } else if main_ref.is_some() {
            return Err(invalid_data!(
                "Current snapshot is not set, but main branch exists"
            ));
        }

        Ok(())
    }

    /// Validate that for V1 Metadata the last_sequence_number is 0
    fn validate_snapshot_sequence_number(&self) -> Result<()> {
        if self.format_version < FormatVersion::V2 && self.last_sequence_number != 0 {
            return Err(invalid_data!(
                "Last sequence number must be 0 in v1. Found {}",
                self.last_sequence_number
            ));
        }

        if self.format_version >= FormatVersion::V2
            && let Some(snapshot) = self
                .snapshots
                .values()
                .find(|snapshot| snapshot.sequence_number() > self.last_sequence_number)
        {
            return Err(invalid_data!(
                "Invalid snapshot with id {} and sequence number {} greater than last sequence number {}",
                snapshot.snapshot_id(),
                snapshot.sequence_number(),
                self.last_sequence_number
            ));
        }

        Ok(())
    }

    /// Validate snapshots logs are chronological and last updated is after the last snapshot log.
    fn validate_chronological_snapshot_logs(&self) -> Result<()> {
        for window in self.snapshot_log.windows(2) {
            let (prev, curr) = (&window[0], &window[1]);
            // commits can happen concurrently from different machines.
            // A tolerance helps us avoid failure for small clock skew
            if curr.timestamp_ms - prev.timestamp_ms < -ONE_MINUTE_MS {
                return Err(invalid_data!("Expected sorted snapshot log entries"));
            }
        }

        if let Some(last) = self.snapshot_log.last() {
            // commits can happen concurrently from different machines.
            // A tolerance helps us avoid failure for small clock skew
            if self.last_updated_ms - last.timestamp_ms < -ONE_MINUTE_MS {
                return Err(invalid_data!(
                    "Invalid update timestamp {}: before last snapshot log entry at {}",
                    self.last_updated_ms,
                    last.timestamp_ms
                ));
            }
        }
        Ok(())
    }

    fn validate_chronological_metadata_logs(&self) -> Result<()> {
        for window in self.metadata_log.windows(2) {
            let (prev, curr) = (&window[0], &window[1]);
            // commits can happen concurrently from different machines.
            // A tolerance helps us avoid failure for small clock skew
            if curr.timestamp_ms - prev.timestamp_ms < -ONE_MINUTE_MS {
                return Err(invalid_data!("Expected sorted metadata log entries"));
            }
        }

        if let Some(last) = self.metadata_log.last() {
            // commits can happen concurrently from different machines.
            // A tolerance helps us avoid failure for small clock skew
            if self.last_updated_ms - last.timestamp_ms < -ONE_MINUTE_MS {
                return Err(invalid_data!(
                    "Invalid update timestamp {}: before last metadata log entry at {}",
                    self.last_updated_ms,
                    last.timestamp_ms
                ));
            }
        }

        Ok(())
    }

    /// Validates that every type used in the current schema is supported by the
    /// table's format version.  Delegates to [`Schema::check_format_compatibility`].
    fn validate_schema_format_compatibility(&self) -> Result<()> {
        self.current_schema()
            .check_format_compatibility(self.format_version)
    }
}

pub(super) mod _serde {
    use std::borrow::BorrowMut;
    /// This is a helper module that defines types to help with serialization/deserialization.
    /// For deserialization the input first gets read into either the [TableMetadataV1] or [TableMetadataV2] struct
    /// and then converted into the [TableMetadata] struct. Serialization works the other way around.
    /// [TableMetadataV1] and [TableMetadataV2] are internal struct that are only used for serialization and deserialization.
    use std::collections::HashMap;
    /// This is a helper module that defines types to help with serialization/deserialization.
    /// For deserialization the input first gets read into either the [TableMetadataV1] or [TableMetadataV2] struct
    /// and then converted into the [TableMetadata] struct. Serialization works the other way around.
    /// [TableMetadataV1] and [TableMetadataV2] are internal struct that are only used for serialization and deserialization.
    use std::sync::Arc;

    use serde::{Deserialize, Serialize};
    use uuid::Uuid;

    use super::{
        DEFAULT_PARTITION_SPEC_ID, EMPTY_SNAPSHOT_ID, FormatVersion, MAIN_BRANCH, MetadataLog,
        SnapshotLog, TableMetadata,
    };
    use crate::error::invalid_data;
    use crate::spec::schema::_serde::{SchemaV1, SchemaV2};
    use crate::spec::snapshot::_serde::{SnapshotV1, SnapshotV2, SnapshotV3};
    use crate::spec::{
        EncryptedKey, INITIAL_ROW_ID, PartitionField, PartitionSpec, PartitionSpecRef,
        PartitionStatisticsFile, Schema, SchemaRef, Snapshot, SnapshotReference, SnapshotRetention,
        SortOrder, StatisticsFile,
    };
    use crate::{Error, ErrorKind};

    #[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
    #[serde(untagged)]
    pub(super) enum TableMetadataEnum {
        V3(TableMetadataV3),
        V2(TableMetadataV2),
        V1(TableMetadataV1),
    }

    #[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
    #[serde(rename_all = "kebab-case")]
    /// Defines the structure of a v2 table metadata for serialization/deserialization
    pub(super) struct TableMetadataV3 {
        pub format_version: VersionNumber<3>,
        #[serde(flatten)]
        pub shared: TableMetadataV2V3Shared,
        pub next_row_id: u64,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub encryption_keys: Option<Vec<EncryptedKey>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub snapshots: Option<Vec<SnapshotV3>>,
    }

    #[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
    #[serde(rename_all = "kebab-case")]
    /// Defines the structure of a v2 table metadata for serialization/deserialization
    pub(super) struct TableMetadataV2V3Shared {
        pub table_uuid: Uuid,
        pub location: String,
        pub last_sequence_number: i64,
        pub last_updated_ms: i64,
        pub last_column_id: i32,
        pub schemas: Vec<SchemaV2>,
        pub current_schema_id: i32,
        pub partition_specs: Vec<PartitionSpec>,
        pub default_spec_id: i32,
        pub last_partition_id: i32,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub properties: Option<HashMap<String, String>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub current_snapshot_id: Option<i64>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub snapshot_log: Option<Vec<SnapshotLog>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub metadata_log: Option<Vec<MetadataLog>>,
        pub sort_orders: Vec<SortOrder>,
        pub default_sort_order_id: i64,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub refs: Option<HashMap<String, SnapshotReference>>,
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub statistics: Vec<StatisticsFile>,
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub partition_statistics: Vec<PartitionStatisticsFile>,
    }

    #[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
    #[serde(rename_all = "kebab-case")]
    /// Defines the structure of a v2 table metadata for serialization/deserialization
    pub(super) struct TableMetadataV2 {
        pub format_version: VersionNumber<2>,
        #[serde(flatten)]
        pub shared: TableMetadataV2V3Shared,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub snapshots: Option<Vec<SnapshotV2>>,
    }

    #[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
    #[serde(rename_all = "kebab-case")]
    /// Defines the structure of a v1 table metadata for serialization/deserialization
    pub(super) struct TableMetadataV1 {
        pub format_version: VersionNumber<1>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub table_uuid: Option<Uuid>,
        pub location: String,
        pub last_updated_ms: i64,
        pub last_column_id: i32,
        /// `schema` is optional to prioritize `schemas` and `current-schema-id`, allowing liberal reading of V1 metadata.
        pub schema: Option<SchemaV1>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub schemas: Option<Vec<SchemaV1>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub current_schema_id: Option<i32>,
        /// `partition_spec` is optional to prioritize `partition_specs`, aligning with liberal reading of potentially invalid V1 metadata.
        pub partition_spec: Option<Vec<PartitionField>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub partition_specs: Option<Vec<PartitionSpec>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub default_spec_id: Option<i32>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub last_partition_id: Option<i32>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub properties: Option<HashMap<String, String>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub current_snapshot_id: Option<i64>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub snapshots: Option<Vec<SnapshotV1>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub snapshot_log: Option<Vec<SnapshotLog>>,
        #[serde(skip_serializing_if = "Option::is_none")]
        pub metadata_log: Option<Vec<MetadataLog>>,
        pub sort_orders: Option<Vec<SortOrder>>,
        pub default_sort_order_id: Option<i64>,
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub statistics: Vec<StatisticsFile>,
        #[serde(default, skip_serializing_if = "Vec::is_empty")]
        pub partition_statistics: Vec<PartitionStatisticsFile>,
    }

    /// Helper to serialize and deserialize the format version.
    #[derive(Debug, PartialEq, Eq)]
    pub(crate) struct VersionNumber<const V: u8>;

    impl Serialize for TableMetadata {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where S: serde::Serializer {
            // we must do a clone here
            let table_metadata_enum: TableMetadataEnum =
                self.clone().try_into().map_err(serde::ser::Error::custom)?;

            table_metadata_enum.serialize(serializer)
        }
    }

    impl<const V: u8> Serialize for VersionNumber<V> {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where S: serde::Serializer {
            serializer.serialize_u8(V)
        }
    }

    impl<'de, const V: u8> Deserialize<'de> for VersionNumber<V> {
        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
        where D: serde::Deserializer<'de> {
            let value = u8::deserialize(deserializer)?;
            if value == V {
                Ok(VersionNumber::<V>)
            } else {
                Err(serde::de::Error::custom("Invalid Version"))
            }
        }
    }

    impl TryFrom<TableMetadataEnum> for TableMetadata {
        type Error = Error;
        fn try_from(value: TableMetadataEnum) -> Result<Self, Error> {
            match value {
                TableMetadataEnum::V3(value) => value.try_into(),
                TableMetadataEnum::V2(value) => value.try_into(),
                TableMetadataEnum::V1(value) => value.try_into(),
            }
        }
    }

    impl TryFrom<TableMetadata> for TableMetadataEnum {
        type Error = Error;
        fn try_from(value: TableMetadata) -> Result<Self, Error> {
            Ok(match value.format_version {
                FormatVersion::V3 => TableMetadataEnum::V3(value.try_into()?),
                FormatVersion::V2 => TableMetadataEnum::V2(value.into()),
                FormatVersion::V1 => TableMetadataEnum::V1(value.try_into()?),
            })
        }
    }

    impl TryFrom<TableMetadataV3> for TableMetadata {
        type Error = Error;
        fn try_from(value: TableMetadataV3) -> Result<Self, Error> {
            let TableMetadataV3 {
                format_version: _,
                shared: value,
                next_row_id,
                encryption_keys,
                snapshots,
            } = value;
            let current_snapshot_id = if value.current_snapshot_id == Some(EMPTY_SNAPSHOT_ID) {
                None
            } else {
                value.current_snapshot_id
            };
            let schemas = HashMap::from_iter(
                value
                    .schemas
                    .into_iter()
                    .map(|schema| Ok((schema.schema_id, Arc::new(schema.try_into()?))))
                    .collect::<Result<Vec<_>, Error>>()?,
            );

            let current_schema: &SchemaRef =
                schemas.get(&value.current_schema_id).ok_or_else(|| {
                    invalid_data!(
                        "No schema exists with the current schema id {}.",
                        value.current_schema_id
                    )
                })?;
            let partition_specs = HashMap::from_iter(
                value
                    .partition_specs
                    .into_iter()
                    .map(|x| (x.spec_id(), Arc::new(x))),
            );
            let default_spec_id = value.default_spec_id;
            let default_spec: PartitionSpecRef = partition_specs
                .get(&value.default_spec_id)
                .map(|spec| (**spec).clone())
                .or_else(|| {
                    (DEFAULT_PARTITION_SPEC_ID == default_spec_id)
                        .then(PartitionSpec::unpartition_spec)
                })
                .ok_or_else(|| invalid_data!("Default partition spec {default_spec_id} not found"))?
                .into();
            let default_partition_type = default_spec.partition_type(current_schema)?;

            let mut metadata = TableMetadata {
                format_version: FormatVersion::V3,
                table_uuid: value.table_uuid,
                location: value.location,
                last_sequence_number: value.last_sequence_number,
                last_updated_ms: value.last_updated_ms,
                last_column_id: value.last_column_id,
                current_schema_id: value.current_schema_id,
                schemas,
                partition_specs,
                default_partition_type,
                default_spec,
                last_partition_id: value.last_partition_id,
                properties: value.properties.unwrap_or_default(),
                current_snapshot_id,
                snapshots: snapshots
                    .map(|snapshots| {
                        HashMap::from_iter(
                            snapshots
                                .into_iter()
                                .map(|x| (x.snapshot_id, Arc::new(x.into()))),
                        )
                    })
                    .unwrap_or_default(),
                snapshot_log: value.snapshot_log.unwrap_or_default(),
                metadata_log: value.metadata_log.unwrap_or_default(),
                sort_orders: HashMap::from_iter(
                    value
                        .sort_orders
                        .into_iter()
                        .map(|x| (x.order_id, Arc::new(x))),
                ),
                default_sort_order_id: value.default_sort_order_id,
                refs: value.refs.unwrap_or_else(|| {
                    if let Some(snapshot_id) = current_snapshot_id {
                        HashMap::from_iter(vec![(MAIN_BRANCH.to_string(), SnapshotReference {
                            snapshot_id,
                            retention: SnapshotRetention::Branch {
                                min_snapshots_to_keep: None,
                                max_snapshot_age_ms: None,
                                max_ref_age_ms: None,
                            },
                        })])
                    } else {
                        HashMap::new()
                    }
                }),
                statistics: index_statistics(value.statistics),
                partition_statistics: index_partition_statistics(value.partition_statistics),
                encryption_keys: encryption_keys
                    .map(|keys| {
                        HashMap::from_iter(keys.into_iter().map(|key| (key.key_id.clone(), key)))
                    })
                    .unwrap_or_default(),
                next_row_id,
            };

            metadata.borrow_mut().try_normalize()?;
            Ok(metadata)
        }
    }

    impl TryFrom<TableMetadataV2> for TableMetadata {
        type Error = Error;
        fn try_from(value: TableMetadataV2) -> Result<Self, Error> {
            let snapshots = value.snapshots;
            let value = value.shared;
            let current_snapshot_id = if value.current_snapshot_id == Some(EMPTY_SNAPSHOT_ID) {
                None
            } else {
                value.current_snapshot_id
            };
            let schemas = HashMap::from_iter(
                value
                    .schemas
                    .into_iter()
                    .map(|schema| Ok((schema.schema_id, Arc::new(schema.try_into()?))))
                    .collect::<Result<Vec<_>, Error>>()?,
            );

            let current_schema: &SchemaRef =
                schemas.get(&value.current_schema_id).ok_or_else(|| {
                    invalid_data!(
                        "No schema exists with the current schema id {}.",
                        value.current_schema_id
                    )
                })?;
            let partition_specs = HashMap::from_iter(
                value
                    .partition_specs
                    .into_iter()
                    .map(|x| (x.spec_id(), Arc::new(x))),
            );
            let default_spec_id = value.default_spec_id;
            let default_spec: PartitionSpecRef = partition_specs
                .get(&value.default_spec_id)
                .map(|spec| (**spec).clone())
                .or_else(|| {
                    (DEFAULT_PARTITION_SPEC_ID == default_spec_id)
                        .then(PartitionSpec::unpartition_spec)
                })
                .ok_or_else(|| invalid_data!("Default partition spec {default_spec_id} not found"))?
                .into();
            let default_partition_type = default_spec.partition_type(current_schema)?;

            let mut metadata = TableMetadata {
                format_version: FormatVersion::V2,
                table_uuid: value.table_uuid,
                location: value.location,
                last_sequence_number: value.last_sequence_number,
                last_updated_ms: value.last_updated_ms,
                last_column_id: value.last_column_id,
                current_schema_id: value.current_schema_id,
                schemas,
                partition_specs,
                default_partition_type,
                default_spec,
                last_partition_id: value.last_partition_id,
                properties: value.properties.unwrap_or_default(),
                current_snapshot_id,
                snapshots: snapshots
                    .map(|snapshots| {
                        HashMap::from_iter(
                            snapshots
                                .into_iter()
                                .map(|x| (x.snapshot_id, Arc::new(x.into()))),
                        )
                    })
                    .unwrap_or_default(),
                snapshot_log: value.snapshot_log.unwrap_or_default(),
                metadata_log: value.metadata_log.unwrap_or_default(),
                sort_orders: HashMap::from_iter(
                    value
                        .sort_orders
                        .into_iter()
                        .map(|x| (x.order_id, Arc::new(x))),
                ),
                default_sort_order_id: value.default_sort_order_id,
                refs: value.refs.unwrap_or_else(|| {
                    if let Some(snapshot_id) = current_snapshot_id {
                        HashMap::from_iter(vec![(MAIN_BRANCH.to_string(), SnapshotReference {
                            snapshot_id,
                            retention: SnapshotRetention::Branch {
                                min_snapshots_to_keep: None,
                                max_snapshot_age_ms: None,
                                max_ref_age_ms: None,
                            },
                        })])
                    } else {
                        HashMap::new()
                    }
                }),
                statistics: index_statistics(value.statistics),
                partition_statistics: index_partition_statistics(value.partition_statistics),
                encryption_keys: HashMap::new(),
                next_row_id: INITIAL_ROW_ID,
            };

            metadata.borrow_mut().try_normalize()?;
            Ok(metadata)
        }
    }

    impl TryFrom<TableMetadataV1> for TableMetadata {
        type Error = Error;
        fn try_from(value: TableMetadataV1) -> Result<Self, Error> {
            let current_snapshot_id = if value.current_snapshot_id == Some(EMPTY_SNAPSHOT_ID) {
                None
            } else {
                value.current_snapshot_id
            };

            let (schemas, current_schema_id, current_schema) =
                if let (Some(schemas_vec), Some(schema_id)) =
                    (&value.schemas, value.current_schema_id)
                {
                    // Option 1: Use 'schemas' + 'current_schema_id'
                    let schema_map = HashMap::from_iter(
                        schemas_vec
                            .clone()
                            .into_iter()
                            .map(|schema| {
                                let schema: Schema = schema.try_into()?;
                                Ok((schema.schema_id(), Arc::new(schema)))
                            })
                            .collect::<Result<Vec<_>, Error>>()?,
                    );

                    let schema = schema_map
                        .get(&schema_id)
                        .ok_or_else(|| {
                            invalid_data!(
                                "No schema exists with the current schema id {schema_id}."
                            )
                        })?
                        .clone();
                    (schema_map, schema_id, schema)
                } else if let Some(schema) = value.schema {
                    // Option 2: Fall back to `schema`
                    let schema: Schema = schema.try_into()?;
                    let schema_id = schema.schema_id();
                    let schema_arc = Arc::new(schema);
                    let schema_map = HashMap::from_iter(vec![(schema_id, schema_arc.clone())]);
                    (schema_map, schema_id, schema_arc)
                } else {
                    // Option 3: No valid schema configuration found
                    return Err(invalid_data!(
                        "No valid schema configuration found in table metadata"
                    ));
                };

            // Prioritize 'partition_specs' over 'partition_spec'
            let partition_specs = if let Some(specs_vec) = value.partition_specs {
                // Option 1: Use 'partition_specs'
                specs_vec
                    .into_iter()
                    .map(|x| (x.spec_id(), Arc::new(x)))
                    .collect::<HashMap<_, _>>()
            } else if let Some(partition_spec) = value.partition_spec {
                // Option 2: Fall back to 'partition_spec'
                let spec = PartitionSpec::builder(current_schema.clone())
                    .with_spec_id(DEFAULT_PARTITION_SPEC_ID)
                    .add_unbound_fields(partition_spec.into_iter().map(|f| f.into_unbound()))?
                    .build()?;

                HashMap::from_iter(vec![(DEFAULT_PARTITION_SPEC_ID, Arc::new(spec))])
            } else {
                // Option 3: Create empty partition spec
                let spec = PartitionSpec::builder(current_schema.clone())
                    .with_spec_id(DEFAULT_PARTITION_SPEC_ID)
                    .build()?;

                HashMap::from_iter(vec![(DEFAULT_PARTITION_SPEC_ID, Arc::new(spec))])
            };

            // Get the default_spec_id, prioritizing the explicit value if provided
            let default_spec_id = value
                .default_spec_id
                .unwrap_or_else(|| partition_specs.keys().copied().max().unwrap_or_default());

            // Get the default spec
            let default_spec: PartitionSpecRef = partition_specs
                .get(&default_spec_id)
                .map(|x| Arc::unwrap_or_clone(x.clone()))
                .ok_or_else(|| invalid_data!("Default partition spec {default_spec_id} not found"))?
                .into();
            let default_partition_type = default_spec.partition_type(&current_schema)?;

            let mut metadata = TableMetadata {
                format_version: FormatVersion::V1,
                table_uuid: value.table_uuid.unwrap_or_default(),
                location: value.location,
                last_sequence_number: 0,
                last_updated_ms: value.last_updated_ms,
                last_column_id: value.last_column_id,
                current_schema_id,
                default_spec,
                default_partition_type,
                last_partition_id: value
                    .last_partition_id
                    .unwrap_or_else(|| partition_specs.keys().copied().max().unwrap_or_default()),
                partition_specs,
                schemas,
                properties: value.properties.unwrap_or_default(),
                current_snapshot_id,
                snapshots: value
                    .snapshots
                    .map(|snapshots| {
                        Ok::<_, Error>(HashMap::from_iter(
                            snapshots
                                .into_iter()
                                .map(|x| Ok((x.snapshot_id, Arc::new(x.try_into()?))))
                                .collect::<Result<Vec<_>, Error>>()?,
                        ))
                    })
                    .transpose()?
                    .unwrap_or_default(),
                snapshot_log: value.snapshot_log.unwrap_or_default(),
                metadata_log: value.metadata_log.unwrap_or_default(),
                sort_orders: match value.sort_orders {
                    Some(sort_orders) => HashMap::from_iter(
                        sort_orders.into_iter().map(|x| (x.order_id, Arc::new(x))),
                    ),
                    None => HashMap::new(),
                },
                default_sort_order_id: value
                    .default_sort_order_id
                    .unwrap_or(SortOrder::UNSORTED_ORDER_ID),
                refs: if let Some(snapshot_id) = current_snapshot_id {
                    HashMap::from_iter(vec![(MAIN_BRANCH.to_string(), SnapshotReference {
                        snapshot_id,
                        retention: SnapshotRetention::Branch {
                            min_snapshots_to_keep: None,
                            max_snapshot_age_ms: None,
                            max_ref_age_ms: None,
                        },
                    })])
                } else {
                    HashMap::new()
                },
                statistics: index_statistics(value.statistics),
                partition_statistics: index_partition_statistics(value.partition_statistics),
                encryption_keys: HashMap::new(),
                next_row_id: INITIAL_ROW_ID, // v1 has no row lineage
            };

            metadata.borrow_mut().try_normalize()?;
            Ok(metadata)
        }
    }

    impl TryFrom<TableMetadata> for TableMetadataV3 {
        type Error = Error;

        fn try_from(mut v: TableMetadata) -> Result<Self, Self::Error> {
            let next_row_id = v.next_row_id;
            let encryption_keys = std::mem::take(&mut v.encryption_keys);
            let snapshots = std::mem::take(&mut v.snapshots);
            let shared = v.into();

            Ok(TableMetadataV3 {
                format_version: VersionNumber::<3>,
                shared,
                next_row_id,
                encryption_keys: if encryption_keys.is_empty() {
                    None
                } else {
                    Some(encryption_keys.into_values().collect())
                },
                snapshots: if snapshots.is_empty() {
                    None
                } else {
                    Some(
                        snapshots
                            .into_values()
                            .map(|s| SnapshotV3::try_from(Arc::unwrap_or_clone(s)))
                            .collect::<Result<_, _>>()?,
                    )
                },
            })
        }
    }

    impl From<TableMetadata> for TableMetadataV2 {
        fn from(mut v: TableMetadata) -> Self {
            let snapshots = std::mem::take(&mut v.snapshots);
            let shared = v.into();

            TableMetadataV2 {
                format_version: VersionNumber::<2>,
                shared,
                snapshots: if snapshots.is_empty() {
                    None
                } else {
                    Some(
                        snapshots
                            .into_values()
                            .map(|s| SnapshotV2::from(Arc::unwrap_or_clone(s)))
                            .collect(),
                    )
                },
            }
        }
    }

    impl From<TableMetadata> for TableMetadataV2V3Shared {
        fn from(v: TableMetadata) -> Self {
            TableMetadataV2V3Shared {
                table_uuid: v.table_uuid,
                location: v.location,
                last_sequence_number: v.last_sequence_number,
                last_updated_ms: v.last_updated_ms,
                last_column_id: v.last_column_id,
                schemas: v
                    .schemas
                    .into_values()
                    .map(|x| {
                        Arc::try_unwrap(x)
                            .unwrap_or_else(|schema| schema.as_ref().clone())
                            .into()
                    })
                    .collect(),
                current_schema_id: v.current_schema_id,
                partition_specs: v
                    .partition_specs
                    .into_values()
                    .map(|x| Arc::try_unwrap(x).unwrap_or_else(|s| s.as_ref().clone()))
                    .collect(),
                default_spec_id: v.default_spec.spec_id(),
                last_partition_id: v.last_partition_id,
                properties: if v.properties.is_empty() {
                    None
                } else {
                    Some(v.properties)
                },
                current_snapshot_id: v.current_snapshot_id,
                snapshot_log: if v.snapshot_log.is_empty() {
                    None
                } else {
                    Some(v.snapshot_log)
                },
                metadata_log: if v.metadata_log.is_empty() {
                    None
                } else {
                    Some(v.metadata_log)
                },
                sort_orders: v
                    .sort_orders
                    .into_values()
                    .map(|x| Arc::try_unwrap(x).unwrap_or_else(|s| s.as_ref().clone()))
                    .collect(),
                default_sort_order_id: v.default_sort_order_id,
                refs: Some(v.refs),
                statistics: v.statistics.into_values().collect(),
                partition_statistics: v.partition_statistics.into_values().collect(),
            }
        }
    }

    impl TryFrom<TableMetadata> for TableMetadataV1 {
        type Error = Error;
        fn try_from(v: TableMetadata) -> Result<Self, Error> {
            Ok(TableMetadataV1 {
                format_version: VersionNumber::<1>,
                table_uuid: Some(v.table_uuid),
                location: v.location,
                last_updated_ms: v.last_updated_ms,
                last_column_id: v.last_column_id,
                schema: Some(
                    v.schemas
                        .get(&v.current_schema_id)
                        .ok_or(Error::new(
                            ErrorKind::Unexpected,
                            "current_schema_id not found in schemas",
                        ))?
                        .as_ref()
                        .clone()
                        .into(),
                ),
                schemas: Some(
                    v.schemas
                        .into_values()
                        .map(|x| {
                            Arc::try_unwrap(x)
                                .unwrap_or_else(|schema| schema.as_ref().clone())
                                .into()
                        })
                        .collect(),
                ),
                current_schema_id: Some(v.current_schema_id),
                partition_spec: Some(v.default_spec.fields().to_vec()),
                partition_specs: Some(
                    v.partition_specs
                        .into_values()
                        .map(|x| Arc::try_unwrap(x).unwrap_or_else(|s| s.as_ref().clone()))
                        .collect(),
                ),
                default_spec_id: Some(v.default_spec.spec_id()),
                last_partition_id: Some(v.last_partition_id),
                properties: if v.properties.is_empty() {
                    None
                } else {
                    Some(v.properties)
                },
                current_snapshot_id: v.current_snapshot_id,
                snapshots: if v.snapshots.is_empty() {
                    None
                } else {
                    Some(
                        v.snapshots
                            .into_values()
                            .map(|x| Snapshot::clone(&x).into())
                            .collect(),
                    )
                },
                snapshot_log: if v.snapshot_log.is_empty() {
                    None
                } else {
                    Some(v.snapshot_log)
                },
                metadata_log: if v.metadata_log.is_empty() {
                    None
                } else {
                    Some(v.metadata_log)
                },
                sort_orders: Some(
                    v.sort_orders
                        .into_values()
                        .map(|s| Arc::try_unwrap(s).unwrap_or_else(|s| s.as_ref().clone()))
                        .collect(),
                ),
                default_sort_order_id: Some(v.default_sort_order_id),
                statistics: v.statistics.into_values().collect(),
                partition_statistics: v.partition_statistics.into_values().collect(),
            })
        }
    }

    fn index_statistics(statistics: Vec<StatisticsFile>) -> HashMap<i64, StatisticsFile> {
        statistics
            .into_iter()
            .rev()
            .map(|s| (s.snapshot_id, s))
            .collect()
    }

    fn index_partition_statistics(
        statistics: Vec<PartitionStatisticsFile>,
    ) -> HashMap<i64, PartitionStatisticsFile> {
        statistics
            .into_iter()
            .rev()
            .map(|s| (s.snapshot_id, s))
            .collect()
    }
}

#[derive(Debug, Serialize_repr, Deserialize_repr, PartialEq, Eq, Clone, Copy, Hash)]
#[repr(u8)]
/// Iceberg format version
pub enum FormatVersion {
    /// Iceberg spec version 1
    V1 = 1u8,
    /// Iceberg spec version 2
    V2 = 2u8,
    /// Iceberg spec version 3
    V3 = 3u8,
}

impl PartialOrd for FormatVersion {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl Ord for FormatVersion {
    fn cmp(&self, other: &Self) -> Ordering {
        (*self as u8).cmp(&(*other as u8))
    }
}

impl Display for FormatVersion {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        match self {
            FormatVersion::V1 => write!(f, "v1"),
            FormatVersion::V2 => write!(f, "v2"),
            FormatVersion::V3 => write!(f, "v3"),
        }
    }
}

#[derive(Debug, Serialize, Deserialize, PartialEq, Eq, Clone)]
#[serde(rename_all = "kebab-case")]
/// Encodes changes to the previous metadata files for the table
pub struct MetadataLog {
    /// The file for the log.
    pub metadata_file: String,
    /// Time new metadata was created
    pub timestamp_ms: i64,
}

#[derive(Debug, Serialize, Deserialize, PartialEq, Eq, Clone)]
#[serde(rename_all = "kebab-case")]
/// A log of when each snapshot was made.
pub struct SnapshotLog {
    /// Id of the snapshot.
    pub snapshot_id: i64,
    /// Last updated timestamp
    pub timestamp_ms: i64,
}

impl SnapshotLog {
    /// Returns the last updated timestamp as a [`DateTime<Utc>`] with millisecond precision
    pub fn timestamp(self) -> Result<DateTime<Utc>> {
        timestamp_ms_to_utc(self.timestamp_ms)
    }

    /// Returns the timestamp in milliseconds
    #[inline]
    pub fn timestamp_ms(&self) -> i64 {
        self.timestamp_ms
    }
}

#[cfg(test)]
mod tests {
    use std::collections::HashMap;
    use std::fs;
    use std::sync::Arc;

    use anyhow::Result;
    use base64::Engine as _;
    use pretty_assertions::assert_eq;
    use tempfile::TempDir;
    use uuid::Uuid;

    use super::{FormatVersion, MetadataLog, SnapshotLog, TableMetadataBuilder};
    use crate::catalog::MetadataLocation;
    use crate::compression::CompressionCodec;
    use crate::io::FileIO;
    use crate::spec::table_metadata::TableMetadata;
    use crate::spec::{
        BlobMetadata, EncryptedKey, INITIAL_ROW_ID, Literal, NestedField, NullOrder, Operation,
        PartitionSpec, PartitionStatisticsFile, PrimitiveLiteral, PrimitiveType, Schema, Snapshot,
        SnapshotReference, SnapshotRetention, SortDirection, SortField, SortOrder, StatisticsFile,
        Summary, TableProperties, Transform, Type, UnboundPartitionField, UnboundPartitionSpec,
    };
    use crate::{ErrorKind, TableCreation};

    fn check_table_metadata_serde(json: &str, expected_type: TableMetadata) {
        let desered_type: TableMetadata = serde_json::from_str(json).unwrap();
        assert_eq!(desered_type, expected_type);

        let sered_json = serde_json::to_string(&expected_type).unwrap();
        let parsed_json_value = serde_json::from_str::<TableMetadata>(&sered_json).unwrap();

        assert_eq!(parsed_json_value, desered_type);
    }

    fn get_test_table_metadata(file_name: &str) -> TableMetadata {
        let path = format!("testdata/table_metadata/{file_name}");
        let metadata: String = fs::read_to_string(path).unwrap();

        serde_json::from_str(&metadata).unwrap()
    }

    /// Loads a test table metadata and relocates it to `location`, so that derived
    /// metadata paths point at a writable (e.g. temp) directory.
    fn get_test_table_metadata_at(file_name: &str, location: &str) -> TableMetadata {
        TableMetadataBuilder::new_from_metadata(get_test_table_metadata(file_name), None)
            .set_location(location.to_string())
            .build()
            .unwrap()
            .metadata
    }

    #[test]
    fn test_table_data_v2() {
        let data = r#"
            {
                "format-version" : 2,
                "table-uuid": "fb072c92-a02b-11e9-ae9c-1bb7bc9eca94",
                "location": "s3://b/wh/data.db/table",
                "last-sequence-number" : 1,
                "last-updated-ms": 1515100955770,
                "last-column-id": 1,
                "schemas": [
                    {
                        "schema-id" : 1,
                        "type" : "struct",
                        "fields" :[
                            {
                                "id": 1,
                                "name": "struct_name",
                                "required": true,
                                "type": "fixed[1]"
                            },
                            {
                                "id": 4,
                                "name": "ts",
                                "required": true,
                                "type": "timestamp"
                            }
                        ]
                    }
                ],
                "current-schema-id" : 1,
                "partition-specs": [
                    {
                        "spec-id": 0,
                        "fields": [
                            {
                                "source-id": 4,
                                "field-id": 1000,
                                "name": "ts_day",
                                "transform": "day"
                            }
                        ]
                    }
                ],
                "default-spec-id": 0,
                "last-partition-id": 1000,
                "properties": {
                    "commit.retry.num-retries": "1"
                },
                "metadata-log": [
                    {
                        "metadata-file": "s3://bucket/.../v1.json",
                        "timestamp-ms": 1515100
                    }
                ],
                "refs": {},
                "sort-orders": [
                    {
                    "order-id": 0,
                    "fields": []
                    }
                ],
                "default-sort-order-id": 0
            }
        "#;

        let schema = Schema::builder()
            .with_schema_id(1)
            .with_fields(vec![
                Arc::new(NestedField::required(
                    1,
                    "struct_name",
                    Type::Primitive(PrimitiveType::Fixed(1)),
                )),
                Arc::new(NestedField::required(
                    4,
                    "ts",
                    Type::Primitive(PrimitiveType::Timestamp),
                )),
            ])
            .build()
            .unwrap();

        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .add_unbound_field(
                UnboundPartitionField::builder()
                    .source_ids(vec![4])
                    .field_id(1000)
                    .name("ts_day".to_string())
                    .transform(Transform::Day)
                    .build()
                    .unwrap(),
            )
            .unwrap()
            .build()
            .unwrap();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V2,
            table_uuid: Uuid::parse_str("fb072c92-a02b-11e9-ae9c-1bb7bc9eca94").unwrap(),
            location: "s3://b/wh/data.db/table".to_string(),
            last_updated_ms: 1515100955770,
            last_column_id: 1,
            schemas: HashMap::from_iter(vec![(1, Arc::new(schema))]),
            current_schema_id: 1,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_partition_type,
            default_spec: partition_spec.into(),
            last_partition_id: 1000,
            default_sort_order_id: 0,
            sort_orders: HashMap::from_iter(vec![(0, SortOrder::unsorted_order().into())]),
            snapshots: HashMap::default(),
            current_snapshot_id: None,
            last_sequence_number: 1,
            properties: HashMap::from_iter(vec![(
                "commit.retry.num-retries".to_string(),
                "1".to_string(),
            )]),
            snapshot_log: Vec::new(),
            metadata_log: vec![MetadataLog {
                metadata_file: "s3://bucket/.../v1.json".to_string(),
                timestamp_ms: 1515100,
            }],
            refs: HashMap::new(),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        let expected_json_value = serde_json::to_value(&expected).unwrap();
        check_table_metadata_serde(data, expected);

        let json_value = serde_json::from_str::<serde_json::Value>(data).unwrap();
        assert_eq!(json_value, expected_json_value);
    }

    #[test]
    fn test_table_data_v3() {
        let data = r#"
            {
                "format-version" : 3,
                "table-uuid": "fb072c92-a02b-11e9-ae9c-1bb7bc9eca94",
                "location": "s3://b/wh/data.db/table",
                "last-sequence-number" : 1,
                "last-updated-ms": 1515100955770,
                "last-column-id": 1,
                "next-row-id": 5,
                "schemas": [
                    {
                        "schema-id" : 1,
                        "type" : "struct",
                        "fields" :[
                            {
                                "id": 4,
                                "name": "ts",
                                "required": true,
                                "type": "timestamp"
                            }
                        ]
                    }
                ],
                "current-schema-id" : 1,
                "partition-specs": [
                    {
                        "spec-id": 0,
                        "fields": [
                            {
                                "source-id": 4,
                                "field-id": 1000,
                                "name": "ts_day",
                                "transform": "day"
                            }
                        ]
                    }
                ],
                "default-spec-id": 0,
                "last-partition-id": 1000,
                "properties": {
                    "commit.retry.num-retries": "1"
                },
                "metadata-log": [
                    {
                        "metadata-file": "s3://bucket/.../v1.json",
                        "timestamp-ms": 1515100
                    }
                ],
                "refs": {},
                "snapshots" : [ {
                    "snapshot-id" : 1,
                    "timestamp-ms" : 1662532818843,
                    "sequence-number" : 0,
                    "first-row-id" : 0,
                    "added-rows" : 4,
                    "key-id" : "key1",
                    "summary" : {
                        "operation" : "append"
                    },
                    "manifest-list" : "/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro",
                    "schema-id" : 0
                    }
                ],
                "encryption-keys": [
                    {
                        "key-id": "key1",
                        "encrypted-by-id": "KMS",
                        "encrypted-key-metadata": "c29tZS1lbmNyeXB0aW9uLWtleQ==",
                        "properties": {
                            "p1": "v1"
                        }
                    }
                ],
                "sort-orders": [
                    {
                    "order-id": 0,
                    "fields": []
                    }
                ],
                "default-sort-order-id": 0
            }
        "#;

        let schema = Schema::builder()
            .with_schema_id(1)
            .with_fields(vec![Arc::new(NestedField::required(
                4,
                "ts",
                Type::Primitive(PrimitiveType::Timestamp),
            ))])
            .build()
            .unwrap();

        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .add_unbound_field(
                UnboundPartitionField::builder()
                    .source_ids(vec![4])
                    .field_id(1000)
                    .name("ts_day".to_string())
                    .transform(Transform::Day)
                    .build()
                    .unwrap(),
            )
            .unwrap()
            .build()
            .unwrap();

        let snapshot = Snapshot::builder()
            .with_snapshot_id(1)
            .with_timestamp_ms(1662532818843)
            .with_sequence_number(0)
            .with_row_range(0, 4)
            .with_encryption_key_id(Some("key1".to_string()))
            .with_summary(Summary {
                operation: Operation::Append,
                additional_properties: HashMap::new(),
            })
            .with_manifest_list("/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro".to_string())
            .with_schema_id(0)
            .build();

        let encryption_key = EncryptedKey::builder()
            .key_id("key1".to_string())
            .encrypted_by_id("KMS".to_string())
            .encrypted_key_metadata(
                base64::prelude::BASE64_STANDARD
                    .decode("c29tZS1lbmNyeXB0aW9uLWtleQ==")
                    .unwrap(),
            )
            .properties(HashMap::from_iter(vec![(
                "p1".to_string(),
                "v1".to_string(),
            )]))
            .build();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V3,
            table_uuid: Uuid::parse_str("fb072c92-a02b-11e9-ae9c-1bb7bc9eca94").unwrap(),
            location: "s3://b/wh/data.db/table".to_string(),
            last_updated_ms: 1515100955770,
            last_column_id: 1,
            schemas: HashMap::from_iter(vec![(1, Arc::new(schema))]),
            current_schema_id: 1,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_partition_type,
            default_spec: partition_spec.into(),
            last_partition_id: 1000,
            default_sort_order_id: 0,
            sort_orders: HashMap::from_iter(vec![(0, SortOrder::unsorted_order().into())]),
            snapshots: HashMap::from_iter(vec![(1, snapshot.into())]),
            current_snapshot_id: None,
            last_sequence_number: 1,
            properties: HashMap::from_iter(vec![(
                "commit.retry.num-retries".to_string(),
                "1".to_string(),
            )]),
            snapshot_log: Vec::new(),
            metadata_log: vec![MetadataLog {
                metadata_file: "s3://bucket/.../v1.json".to_string(),
                timestamp_ms: 1515100,
            }],
            refs: HashMap::new(),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::from_iter(vec![("key1".to_string(), encryption_key)]),
            next_row_id: 5,
        };

        let expected_json_value = serde_json::to_value(&expected).unwrap();
        check_table_metadata_serde(data, expected);

        let json_value = serde_json::from_str::<serde_json::Value>(data).unwrap();
        assert_eq!(json_value, expected_json_value);
    }

    #[test]
    fn test_table_data_v1() {
        let data = r#"
        {
            "format-version" : 1,
            "table-uuid" : "df838b92-0b32-465d-a44e-d39936e538b7",
            "location" : "/home/iceberg/warehouse/nyc/taxis",
            "last-updated-ms" : 1662532818843,
            "last-column-id" : 5,
            "schema" : {
              "type" : "struct",
              "schema-id" : 0,
              "fields" : [ {
                "id" : 1,
                "name" : "vendor_id",
                "required" : false,
                "type" : "long"
              }, {
                "id" : 2,
                "name" : "trip_id",
                "required" : false,
                "type" : "long"
              }, {
                "id" : 3,
                "name" : "trip_distance",
                "required" : false,
                "type" : "float"
              }, {
                "id" : 4,
                "name" : "fare_amount",
                "required" : false,
                "type" : "double"
              }, {
                "id" : 5,
                "name" : "store_and_fwd_flag",
                "required" : false,
                "type" : "string"
              } ]
            },
            "partition-spec" : [ {
              "name" : "vendor_id",
              "transform" : "identity",
              "source-id" : 1,
              "field-id" : 1000
            } ],
            "last-partition-id" : 1000,
            "default-sort-order-id" : 0,
            "sort-orders" : [ {
              "order-id" : 0,
              "fields" : [ ]
            } ],
            "properties" : {
              "owner" : "root"
            },
            "current-snapshot-id" : 638933773299822130,
            "refs" : {
              "main" : {
                "snapshot-id" : 638933773299822130,
                "type" : "branch"
              }
            },
            "snapshots" : [ {
              "snapshot-id" : 638933773299822130,
              "timestamp-ms" : 1662532818843,
              "sequence-number" : 0,
              "summary" : {
                "operation" : "append",
                "spark.app.id" : "local-1662532784305",
                "added-data-files" : "4",
                "added-records" : "4",
                "added-files-size" : "6001"
              },
              "manifest-list" : "/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro",
              "schema-id" : 0
            } ],
            "snapshot-log" : [ {
              "timestamp-ms" : 1662532818843,
              "snapshot-id" : 638933773299822130
            } ],
            "metadata-log" : [ {
              "timestamp-ms" : 1662532805245,
              "metadata-file" : "/home/iceberg/warehouse/nyc/taxis/metadata/00000-8a62c37d-4573-4021-952a-c0baef7d21d0.metadata.json"
            } ]
          }
        "#;

        let schema = Schema::builder()
            .with_fields(vec![
                Arc::new(NestedField::optional(
                    1,
                    "vendor_id",
                    Type::Primitive(PrimitiveType::Long),
                )),
                Arc::new(NestedField::optional(
                    2,
                    "trip_id",
                    Type::Primitive(PrimitiveType::Long),
                )),
                Arc::new(NestedField::optional(
                    3,
                    "trip_distance",
                    Type::Primitive(PrimitiveType::Float),
                )),
                Arc::new(NestedField::optional(
                    4,
                    "fare_amount",
                    Type::Primitive(PrimitiveType::Double),
                )),
                Arc::new(NestedField::optional(
                    5,
                    "store_and_fwd_flag",
                    Type::Primitive(PrimitiveType::String),
                )),
            ])
            .build()
            .unwrap();

        let schema = Arc::new(schema);
        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .add_partition_field("vendor_id", "vendor_id", Transform::Identity)
            .unwrap()
            .build()
            .unwrap();

        let sort_order = SortOrder::builder()
            .with_order_id(0)
            .build_unbound()
            .unwrap();

        let snapshot = Snapshot::builder()
            .with_snapshot_id(638933773299822130)
            .with_timestamp_ms(1662532818843)
            .with_sequence_number(0)
            .with_schema_id(0)
            .with_manifest_list("/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro")
            .with_summary(Summary { operation: Operation::Append, additional_properties: HashMap::from_iter(vec![("spark.app.id".to_string(), "local-1662532784305".to_string()), ("added-data-files".to_string(), "4".to_string()), ("added-records".to_string(), "4".to_string()), ("added-files-size".to_string(), "6001".to_string())]) })
            .build();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V1,
            table_uuid: Uuid::parse_str("df838b92-0b32-465d-a44e-d39936e538b7").unwrap(),
            location: "/home/iceberg/warehouse/nyc/taxis".to_string(),
            last_updated_ms: 1662532818843,
            last_column_id: 5,
            schemas: HashMap::from_iter(vec![(0, schema)]),
            current_schema_id: 0,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_partition_type,
            default_spec: Arc::new(partition_spec),
            last_partition_id: 1000,
            default_sort_order_id: 0,
            sort_orders: HashMap::from_iter(vec![(0, sort_order.into())]),
            snapshots: HashMap::from_iter(vec![(638933773299822130, Arc::new(snapshot))]),
            current_snapshot_id: Some(638933773299822130),
            last_sequence_number: 0,
            properties: HashMap::from_iter(vec![("owner".to_string(), "root".to_string())]),
            snapshot_log: vec![SnapshotLog {
                snapshot_id: 638933773299822130,
                timestamp_ms: 1662532818843,
            }],
            metadata_log: vec![MetadataLog { metadata_file: "/home/iceberg/warehouse/nyc/taxis/metadata/00000-8a62c37d-4573-4021-952a-c0baef7d21d0.metadata.json".to_string(), timestamp_ms: 1662532805245 }],
            refs: HashMap::from_iter(vec![("main".to_string(), SnapshotReference { snapshot_id: 638933773299822130, retention: SnapshotRetention::Branch { min_snapshots_to_keep: None, max_snapshot_age_ms: None, max_ref_age_ms: None } })]),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        check_table_metadata_serde(data, expected);
    }

    #[test]
    fn test_table_data_v2_no_snapshots() {
        let data = r#"
        {
            "format-version" : 2,
            "table-uuid": "fb072c92-a02b-11e9-ae9c-1bb7bc9eca94",
            "location": "s3://b/wh/data.db/table",
            "last-sequence-number" : 1,
            "last-updated-ms": 1515100955770,
            "last-column-id": 1,
            "schemas": [
                {
                    "schema-id" : 1,
                    "type" : "struct",
                    "fields" :[
                        {
                            "id": 1,
                            "name": "struct_name",
                            "required": true,
                            "type": "fixed[1]"
                        }
                    ]
                }
            ],
            "current-schema-id" : 1,
            "partition-specs": [
                {
                    "spec-id": 0,
                    "fields": []
                }
            ],
            "refs": {},
            "default-spec-id": 0,
            "last-partition-id": 1000,
            "metadata-log": [
                {
                    "metadata-file": "s3://bucket/.../v1.json",
                    "timestamp-ms": 1515100
                }
            ],
            "sort-orders": [
                {
                "order-id": 0,
                "fields": []
                }
            ],
            "default-sort-order-id": 0
        }
        "#;

        let schema = Schema::builder()
            .with_schema_id(1)
            .with_fields(vec![Arc::new(NestedField::required(
                1,
                "struct_name",
                Type::Primitive(PrimitiveType::Fixed(1)),
            ))])
            .build()
            .unwrap();

        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .build()
            .unwrap();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V2,
            table_uuid: Uuid::parse_str("fb072c92-a02b-11e9-ae9c-1bb7bc9eca94").unwrap(),
            location: "s3://b/wh/data.db/table".to_string(),
            last_updated_ms: 1515100955770,
            last_column_id: 1,
            schemas: HashMap::from_iter(vec![(1, Arc::new(schema))]),
            current_schema_id: 1,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_partition_type,
            default_spec: partition_spec.into(),
            last_partition_id: 1000,
            default_sort_order_id: 0,
            sort_orders: HashMap::from_iter(vec![(0, SortOrder::unsorted_order().into())]),
            snapshots: HashMap::default(),
            current_snapshot_id: None,
            last_sequence_number: 1,
            properties: HashMap::new(),
            snapshot_log: Vec::new(),
            metadata_log: vec![MetadataLog {
                metadata_file: "s3://bucket/.../v1.json".to_string(),
                timestamp_ms: 1515100,
            }],
            refs: HashMap::new(),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        let expected_json_value = serde_json::to_value(&expected).unwrap();
        check_table_metadata_serde(data, expected);

        let json_value = serde_json::from_str::<serde_json::Value>(data).unwrap();
        assert_eq!(json_value, expected_json_value);
    }

    #[test]
    fn test_current_snapshot_id_must_match_main_branch() {
        let data = r#"
        {
            "format-version" : 2,
            "table-uuid": "fb072c92-a02b-11e9-ae9c-1bb7bc9eca94",
            "location": "s3://b/wh/data.db/table",
            "last-sequence-number" : 1,
            "last-updated-ms": 1515100955770,
            "last-column-id": 1,
            "schemas": [
                {
                    "schema-id" : 1,
                    "type" : "struct",
                    "fields" :[
                        {
                            "id": 1,
                            "name": "struct_name",
                            "required": true,
                            "type": "fixed[1]"
                        },
                        {
                            "id": 4,
                            "name": "ts",
                            "required": true,
                            "type": "timestamp"
                        }
                    ]
                }
            ],
            "current-schema-id" : 1,
            "partition-specs": [
                {
                    "spec-id": 0,
                    "fields": [
                        {
                            "source-id": 4,
                            "field-id": 1000,
                            "name": "ts_day",
                            "transform": "day"
                        }
                    ]
                }
            ],
            "default-spec-id": 0,
            "last-partition-id": 1000,
            "properties": {
                "commit.retry.num-retries": "1"
            },
            "metadata-log": [
                {
                    "metadata-file": "s3://bucket/.../v1.json",
                    "timestamp-ms": 1515100
                }
            ],
            "sort-orders": [
                {
                "order-id": 0,
                "fields": []
                }
            ],
            "default-sort-order-id": 0,
            "current-snapshot-id" : 1,
            "refs" : {
              "main" : {
                "snapshot-id" : 2,
                "type" : "branch"
              }
            },
            "snapshots" : [ {
              "snapshot-id" : 1,
              "timestamp-ms" : 1662532818843,
              "sequence-number" : 0,
              "summary" : {
                "operation" : "append",
                "spark.app.id" : "local-1662532784305",
                "added-data-files" : "4",
                "added-records" : "4",
                "added-files-size" : "6001"
              },
              "manifest-list" : "/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro",
              "schema-id" : 0
            },
            {
              "snapshot-id" : 2,
              "timestamp-ms" : 1662532818844,
              "sequence-number" : 0,
              "summary" : {
                "operation" : "append",
                "spark.app.id" : "local-1662532784305",
                "added-data-files" : "4",
                "added-records" : "4",
                "added-files-size" : "6001"
              },
              "manifest-list" : "/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro",
              "schema-id" : 0
            } ]
        }
    "#;

        let err = serde_json::from_str::<TableMetadata>(data).unwrap_err();
        assert!(
            err.to_string()
                .contains("Current snapshot id does not match main branch")
        );
    }

    #[test]
    fn test_main_without_current() {
        let data = r#"
        {
            "format-version" : 2,
            "table-uuid": "fb072c92-a02b-11e9-ae9c-1bb7bc9eca94",
            "location": "s3://b/wh/data.db/table",
            "last-sequence-number" : 1,
            "last-updated-ms": 1515100955770,
            "last-column-id": 1,
            "schemas": [
                {
                    "schema-id" : 1,
                    "type" : "struct",
                    "fields" :[
                        {
                            "id": 1,
                            "name": "struct_name",
                            "required": true,
                            "type": "fixed[1]"
                        },
                        {
                            "id": 4,
                            "name": "ts",
                            "required": true,
                            "type": "timestamp"
                        }
                    ]
                }
            ],
            "current-schema-id" : 1,
            "partition-specs": [
                {
                    "spec-id": 0,
                    "fields": [
                        {
                            "source-id": 4,
                            "field-id": 1000,
                            "name": "ts_day",
                            "transform": "day"
                        }
                    ]
                }
            ],
            "default-spec-id": 0,
            "last-partition-id": 1000,
            "properties": {
                "commit.retry.num-retries": "1"
            },
            "metadata-log": [
                {
                    "metadata-file": "s3://bucket/.../v1.json",
                    "timestamp-ms": 1515100
                }
            ],
            "sort-orders": [
                {
                "order-id": 0,
                "fields": []
                }
            ],
            "default-sort-order-id": 0,
            "refs" : {
              "main" : {
                "snapshot-id" : 1,
                "type" : "branch"
              }
            },
            "snapshots" : [ {
              "snapshot-id" : 1,
              "timestamp-ms" : 1662532818843,
              "sequence-number" : 0,
              "summary" : {
                "operation" : "append",
                "spark.app.id" : "local-1662532784305",
                "added-data-files" : "4",
                "added-records" : "4",
                "added-files-size" : "6001"
              },
              "manifest-list" : "/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro",
              "schema-id" : 0
            } ]
        }
    "#;

        let err = serde_json::from_str::<TableMetadata>(data).unwrap_err();
        assert!(
            err.to_string()
                .contains("Current snapshot is not set, but main branch exists")
        );
    }

    #[test]
    fn test_branch_snapshot_missing() {
        let data = r#"
        {
            "format-version" : 2,
            "table-uuid": "fb072c92-a02b-11e9-ae9c-1bb7bc9eca94",
            "location": "s3://b/wh/data.db/table",
            "last-sequence-number" : 1,
            "last-updated-ms": 1515100955770,
            "last-column-id": 1,
            "schemas": [
                {
                    "schema-id" : 1,
                    "type" : "struct",
                    "fields" :[
                        {
                            "id": 1,
                            "name": "struct_name",
                            "required": true,
                            "type": "fixed[1]"
                        },
                        {
                            "id": 4,
                            "name": "ts",
                            "required": true,
                            "type": "timestamp"
                        }
                    ]
                }
            ],
            "current-schema-id" : 1,
            "partition-specs": [
                {
                    "spec-id": 0,
                    "fields": [
                        {
                            "source-id": 4,
                            "field-id": 1000,
                            "name": "ts_day",
                            "transform": "day"
                        }
                    ]
                }
            ],
            "default-spec-id": 0,
            "last-partition-id": 1000,
            "properties": {
                "commit.retry.num-retries": "1"
            },
            "metadata-log": [
                {
                    "metadata-file": "s3://bucket/.../v1.json",
                    "timestamp-ms": 1515100
                }
            ],
            "sort-orders": [
                {
                "order-id": 0,
                "fields": []
                }
            ],
            "default-sort-order-id": 0,
            "refs" : {
              "main" : {
                "snapshot-id" : 1,
                "type" : "branch"
              },
              "foo" : {
                "snapshot-id" : 2,
                "type" : "branch"
              }
            },
            "snapshots" : [ {
              "snapshot-id" : 1,
              "timestamp-ms" : 1662532818843,
              "sequence-number" : 0,
              "summary" : {
                "operation" : "append",
                "spark.app.id" : "local-1662532784305",
                "added-data-files" : "4",
                "added-records" : "4",
                "added-files-size" : "6001"
              },
              "manifest-list" : "/home/iceberg/warehouse/nyc/taxis/metadata/snap-638933773299822130-1-7e6760f0-4f6c-4b23-b907-0a5a174e3863.avro",
              "schema-id" : 0
            } ]
        }
    "#;

        let err = serde_json::from_str::<TableMetadata>(data).unwrap_err();
        assert!(
            err.to_string().contains(
                "Snapshot for reference foo does not exist in the existing snapshots list"
            )
        );
    }

    #[test]
    fn test_v2_wrong_max_snapshot_sequence_number() {
        let data = r#"
        {
            "format-version": 2,
            "table-uuid": "9c12d441-03fe-4693-9a96-a0705ddf69c1",
            "location": "s3://bucket/test/location",
            "last-sequence-number": 1,
            "last-updated-ms": 1602638573590,
            "last-column-id": 3,
            "current-schema-id": 0,
            "schemas": [
                {
                    "type": "struct",
                    "schema-id": 0,
                    "fields": [
                        {
                            "id": 1,
                            "name": "x",
                            "required": true,
                            "type": "long"
                        }
                    ]
                }
            ],
            "default-spec-id": 0,
            "partition-specs": [
                {
                    "spec-id": 0,
                    "fields": []
                }
            ],
            "last-partition-id": 1000,
            "default-sort-order-id": 0,
            "sort-orders": [
                {
                    "order-id": 0,
                    "fields": []
                }
            ],
            "properties": {},
            "current-snapshot-id": 3055729675574597004,
            "snapshots": [
                {
                    "snapshot-id": 3055729675574597004,
                    "timestamp-ms": 1555100955770,
                    "sequence-number": 4,
                    "summary": {
                        "operation": "append"
                    },
                    "manifest-list": "s3://a/b/2.avro",
                    "schema-id": 0
                }
            ],
            "statistics": [],
            "snapshot-log": [],
            "metadata-log": []
        }
    "#;

        let err = serde_json::from_str::<TableMetadata>(data).unwrap_err();
        assert!(err.to_string().contains(
            "Invalid snapshot with id 3055729675574597004 and sequence number 4 greater than last sequence number 1"
        ));

        // Change max sequence number to 4 - should work
        let data = data.replace(
            r#""last-sequence-number": 1,"#,
            r#""last-sequence-number": 4,"#,
        );
        let metadata = serde_json::from_str::<TableMetadata>(data.as_str()).unwrap();
        assert_eq!(metadata.last_sequence_number, 4);

        // Change max sequence number to 5 - should work
        let data = data.replace(
            r#""last-sequence-number": 4,"#,
            r#""last-sequence-number": 5,"#,
        );
        let metadata = serde_json::from_str::<TableMetadata>(data.as_str()).unwrap();
        assert_eq!(metadata.last_sequence_number, 5);
    }

    #[test]
    fn test_statistic_files() {
        let data = r#"
        {
            "format-version": 2,
            "table-uuid": "9c12d441-03fe-4693-9a96-a0705ddf69c1",
            "location": "s3://bucket/test/location",
            "last-sequence-number": 34,
            "last-updated-ms": 1602638573590,
            "last-column-id": 3,
            "current-schema-id": 0,
            "schemas": [
                {
                    "type": "struct",
                    "schema-id": 0,
                    "fields": [
                        {
                            "id": 1,
                            "name": "x",
                            "required": true,
                            "type": "long"
                        }
                    ]
                }
            ],
            "default-spec-id": 0,
            "partition-specs": [
                {
                    "spec-id": 0,
                    "fields": []
                }
            ],
            "last-partition-id": 1000,
            "default-sort-order-id": 0,
            "sort-orders": [
                {
                    "order-id": 0,
                    "fields": []
                }
            ],
            "properties": {},
            "current-snapshot-id": 3055729675574597004,
            "snapshots": [
                {
                    "snapshot-id": 3055729675574597004,
                    "timestamp-ms": 1555100955770,
                    "sequence-number": 1,
                    "summary": {
                        "operation": "append"
                    },
                    "manifest-list": "s3://a/b/2.avro",
                    "schema-id": 0
                }
            ],
            "statistics": [
                {
                    "snapshot-id": 3055729675574597004,
                    "statistics-path": "s3://a/b/stats.puffin",
                    "file-size-in-bytes": 413,
                    "file-footer-size-in-bytes": 42,
                    "blob-metadata": [
                        {
                            "type": "ndv",
                            "snapshot-id": 3055729675574597004,
                            "sequence-number": 1,
                            "fields": [
                                1
                            ]
                        }
                    ]
                }
            ],
            "snapshot-log": [],
            "metadata-log": []
        }
    "#;

        let schema = Schema::builder()
            .with_schema_id(0)
            .with_fields(vec![Arc::new(NestedField::required(
                1,
                "x",
                Type::Primitive(PrimitiveType::Long),
            ))])
            .build()
            .unwrap();
        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .build()
            .unwrap();
        let snapshot = Snapshot::builder()
            .with_snapshot_id(3055729675574597004)
            .with_timestamp_ms(1555100955770)
            .with_sequence_number(1)
            .with_manifest_list("s3://a/b/2.avro")
            .with_schema_id(0)
            .with_summary(Summary {
                operation: Operation::Append,
                additional_properties: HashMap::new(),
            })
            .build();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V2,
            table_uuid: Uuid::parse_str("9c12d441-03fe-4693-9a96-a0705ddf69c1").unwrap(),
            location: "s3://bucket/test/location".to_string(),
            last_updated_ms: 1602638573590,
            last_column_id: 3,
            schemas: HashMap::from_iter(vec![(0, Arc::new(schema))]),
            current_schema_id: 0,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_partition_type,
            default_spec: Arc::new(partition_spec),
            last_partition_id: 1000,
            default_sort_order_id: 0,
            sort_orders: HashMap::from_iter(vec![(0, SortOrder::unsorted_order().into())]),
            snapshots: HashMap::from_iter(vec![(3055729675574597004, Arc::new(snapshot))]),
            current_snapshot_id: Some(3055729675574597004),
            last_sequence_number: 34,
            properties: HashMap::new(),
            snapshot_log: Vec::new(),
            metadata_log: Vec::new(),
            statistics: HashMap::from_iter(vec![(3055729675574597004, StatisticsFile {
                snapshot_id: 3055729675574597004,
                statistics_path: "s3://a/b/stats.puffin".to_string(),
                file_size_in_bytes: 413,
                file_footer_size_in_bytes: 42,
                key_metadata: None,
                blob_metadata: vec![BlobMetadata {
                    snapshot_id: 3055729675574597004,
                    sequence_number: 1,
                    fields: vec![1],
                    r#type: "ndv".to_string(),
                    properties: HashMap::new(),
                }],
            })]),
            partition_statistics: HashMap::new(),
            refs: HashMap::from_iter(vec![("main".to_string(), SnapshotReference {
                snapshot_id: 3055729675574597004,
                retention: SnapshotRetention::Branch {
                    min_snapshots_to_keep: None,
                    max_snapshot_age_ms: None,
                    max_ref_age_ms: None,
                },
            })]),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        check_table_metadata_serde(data, expected);
    }

    #[test]
    fn test_partition_statistics_file() {
        let data = r#"
        {
            "format-version": 2,
            "table-uuid": "9c12d441-03fe-4693-9a96-a0705ddf69c1",
            "location": "s3://bucket/test/location",
            "last-sequence-number": 34,
            "last-updated-ms": 1602638573590,
            "last-column-id": 3,
            "current-schema-id": 0,
            "schemas": [
                {
                    "type": "struct",
                    "schema-id": 0,
                    "fields": [
                        {
                            "id": 1,
                            "name": "x",
                            "required": true,
                            "type": "long"
                        }
                    ]
                }
            ],
            "default-spec-id": 0,
            "partition-specs": [
                {
                    "spec-id": 0,
                    "fields": []
                }
            ],
            "last-partition-id": 1000,
            "default-sort-order-id": 0,
            "sort-orders": [
                {
                    "order-id": 0,
                    "fields": []
                }
            ],
            "properties": {},
            "current-snapshot-id": 3055729675574597004,
            "snapshots": [
                {
                    "snapshot-id": 3055729675574597004,
                    "timestamp-ms": 1555100955770,
                    "sequence-number": 1,
                    "summary": {
                        "operation": "append"
                    },
                    "manifest-list": "s3://a/b/2.avro",
                    "schema-id": 0
                }
            ],
            "partition-statistics": [
                {
                    "snapshot-id": 3055729675574597004,
                    "statistics-path": "s3://a/b/partition-stats.parquet",
                    "file-size-in-bytes": 43
                }
            ],
            "snapshot-log": [],
            "metadata-log": []
        }
        "#;

        let schema = Schema::builder()
            .with_schema_id(0)
            .with_fields(vec![Arc::new(NestedField::required(
                1,
                "x",
                Type::Primitive(PrimitiveType::Long),
            ))])
            .build()
            .unwrap();
        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .build()
            .unwrap();
        let snapshot = Snapshot::builder()
            .with_snapshot_id(3055729675574597004)
            .with_timestamp_ms(1555100955770)
            .with_sequence_number(1)
            .with_manifest_list("s3://a/b/2.avro")
            .with_schema_id(0)
            .with_summary(Summary {
                operation: Operation::Append,
                additional_properties: HashMap::new(),
            })
            .build();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V2,
            table_uuid: Uuid::parse_str("9c12d441-03fe-4693-9a96-a0705ddf69c1").unwrap(),
            location: "s3://bucket/test/location".to_string(),
            last_updated_ms: 1602638573590,
            last_column_id: 3,
            schemas: HashMap::from_iter(vec![(0, Arc::new(schema))]),
            current_schema_id: 0,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_spec: Arc::new(partition_spec),
            default_partition_type,
            last_partition_id: 1000,
            default_sort_order_id: 0,
            sort_orders: HashMap::from_iter(vec![(0, SortOrder::unsorted_order().into())]),
            snapshots: HashMap::from_iter(vec![(3055729675574597004, Arc::new(snapshot))]),
            current_snapshot_id: Some(3055729675574597004),
            last_sequence_number: 34,
            properties: HashMap::new(),
            snapshot_log: Vec::new(),
            metadata_log: Vec::new(),
            statistics: HashMap::new(),
            partition_statistics: HashMap::from_iter(vec![(
                3055729675574597004,
                PartitionStatisticsFile {
                    snapshot_id: 3055729675574597004,
                    statistics_path: "s3://a/b/partition-stats.parquet".to_string(),
                    file_size_in_bytes: 43,
                },
            )]),
            refs: HashMap::from_iter(vec![("main".to_string(), SnapshotReference {
                snapshot_id: 3055729675574597004,
                retention: SnapshotRetention::Branch {
                    min_snapshots_to_keep: None,
                    max_snapshot_age_ms: None,
                    max_ref_age_ms: None,
                },
            })]),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        check_table_metadata_serde(data, expected);
    }

    #[test]
    fn test_invalid_table_uuid() -> Result<()> {
        let data = r#"
            {
                "format-version" : 2,
                "table-uuid": "xxxx"
            }
        "#;
        assert!(serde_json::from_str::<TableMetadata>(data).is_err());
        Ok(())
    }

    #[test]
    fn test_deserialize_table_data_v2_invalid_format_version() -> Result<()> {
        let data = r#"
            {
                "format-version" : 1
            }
        "#;
        assert!(serde_json::from_str::<TableMetadata>(data).is_err());
        Ok(())
    }

    #[test]
    fn test_table_metadata_v3_valid_minimal() {
        let metadata_str =
            fs::read_to_string("testdata/table_metadata/TableMetadataV3ValidMinimal.json").unwrap();

        let table_metadata = serde_json::from_str::<TableMetadata>(&metadata_str).unwrap();
        assert_eq!(table_metadata.format_version, FormatVersion::V3);

        let schema = Schema::builder()
            .with_schema_id(0)
            .with_fields(vec![
                Arc::new(
                    NestedField::required(1, "x", Type::Primitive(PrimitiveType::Long))
                        .with_initial_default(Literal::Primitive(PrimitiveLiteral::Long(1)))
                        .with_write_default(Literal::Primitive(PrimitiveLiteral::Long(1))),
                ),
                Arc::new(
                    NestedField::required(2, "y", Type::Primitive(PrimitiveType::Long))
                        .with_doc("comment"),
                ),
                Arc::new(NestedField::required(
                    3,
                    "z",
                    Type::Primitive(PrimitiveType::Long),
                )),
            ])
            .build()
            .unwrap();

        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .add_unbound_field(
                UnboundPartitionField::builder()
                    .source_ids(vec![1])
                    .field_id(1000)
                    .name("x".to_string())
                    .transform(Transform::Identity)
                    .build()
                    .unwrap(),
            )
            .unwrap()
            .build()
            .unwrap();

        let sort_order = SortOrder::builder()
            .with_order_id(3)
            .with_sort_field(SortField {
                source_id: 2,
                transform: Transform::Identity,
                direction: SortDirection::Ascending,
                null_order: NullOrder::First,
            })
            .with_sort_field(SortField {
                source_id: 3,
                transform: Transform::Bucket(4),
                direction: SortDirection::Descending,
                null_order: NullOrder::Last,
            })
            .build_unbound()
            .unwrap();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V3,
            table_uuid: Uuid::parse_str("9c12d441-03fe-4693-9a96-a0705ddf69c1").unwrap(),
            location: "s3://bucket/test/location".to_string(),
            last_updated_ms: 1602638573590,
            last_column_id: 3,
            schemas: HashMap::from_iter(vec![(0, Arc::new(schema))]),
            current_schema_id: 0,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_spec: Arc::new(partition_spec),
            default_partition_type,
            last_partition_id: 1000,
            default_sort_order_id: 3,
            sort_orders: HashMap::from_iter(vec![(3, sort_order.into())]),
            snapshots: HashMap::default(),
            current_snapshot_id: None,
            last_sequence_number: 34,
            properties: HashMap::new(),
            snapshot_log: Vec::new(),
            metadata_log: Vec::new(),
            refs: HashMap::new(),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::new(),
            next_row_id: 0, // V3 specific field from the JSON
        };

        check_table_metadata_serde(&metadata_str, expected);
    }

    #[test]
    fn test_table_metadata_v2_file_valid() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV2Valid.json").unwrap();

        let schema1 = Schema::builder()
            .with_schema_id(0)
            .with_fields(vec![Arc::new(NestedField::required(
                1,
                "x",
                Type::Primitive(PrimitiveType::Long),
            ))])
            .build()
            .unwrap();

        let schema2 = Schema::builder()
            .with_schema_id(1)
            .with_fields(vec![
                Arc::new(NestedField::required(
                    1,
                    "x",
                    Type::Primitive(PrimitiveType::Long),
                )),
                Arc::new(
                    NestedField::required(2, "y", Type::Primitive(PrimitiveType::Long))
                        .with_doc("comment"),
                ),
                Arc::new(NestedField::required(
                    3,
                    "z",
                    Type::Primitive(PrimitiveType::Long),
                )),
            ])
            .with_identifier_field_ids(vec![1, 2])
            .build()
            .unwrap();

        let partition_spec = PartitionSpec::builder(schema2.clone())
            .with_spec_id(0)
            .add_unbound_field(
                UnboundPartitionField::builder()
                    .source_ids(vec![1])
                    .field_id(1000)
                    .name("x".to_string())
                    .transform(Transform::Identity)
                    .build()
                    .unwrap(),
            )
            .unwrap()
            .build()
            .unwrap();

        let sort_order = SortOrder::builder()
            .with_order_id(3)
            .with_sort_field(SortField {
                source_id: 2,
                transform: Transform::Identity,
                direction: SortDirection::Ascending,
                null_order: NullOrder::First,
            })
            .with_sort_field(SortField {
                source_id: 3,
                transform: Transform::Bucket(4),
                direction: SortDirection::Descending,
                null_order: NullOrder::Last,
            })
            .build_unbound()
            .unwrap();

        let snapshot1 = Snapshot::builder()
            .with_snapshot_id(3051729675574597004)
            .with_timestamp_ms(1515100955770)
            .with_sequence_number(0)
            .with_manifest_list("s3://a/b/1.avro")
            .with_summary(Summary {
                operation: Operation::Append,
                additional_properties: HashMap::new(),
            })
            .build();

        let snapshot2 = Snapshot::builder()
            .with_snapshot_id(3055729675574597004)
            .with_parent_snapshot_id(Some(3051729675574597004))
            .with_timestamp_ms(1555100955770)
            .with_sequence_number(1)
            .with_schema_id(1)
            .with_manifest_list("s3://a/b/2.avro")
            .with_summary(Summary {
                operation: Operation::Append,
                additional_properties: HashMap::new(),
            })
            .build();

        let default_partition_type = partition_spec.partition_type(&schema2).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V2,
            table_uuid: Uuid::parse_str("9c12d441-03fe-4693-9a96-a0705ddf69c1").unwrap(),
            location: "s3://bucket/test/location".to_string(),
            last_updated_ms: 1602638573590,
            last_column_id: 3,
            schemas: HashMap::from_iter(vec![(0, Arc::new(schema1)), (1, Arc::new(schema2))]),
            current_schema_id: 1,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_spec: Arc::new(partition_spec),
            default_partition_type,
            last_partition_id: 1000,
            default_sort_order_id: 3,
            sort_orders: HashMap::from_iter(vec![(3, sort_order.into())]),
            snapshots: HashMap::from_iter(vec![
                (3051729675574597004, Arc::new(snapshot1)),
                (3055729675574597004, Arc::new(snapshot2)),
            ]),
            current_snapshot_id: Some(3055729675574597004),
            last_sequence_number: 34,
            properties: HashMap::new(),
            snapshot_log: vec![
                SnapshotLog {
                    snapshot_id: 3051729675574597004,
                    timestamp_ms: 1515100955770,
                },
                SnapshotLog {
                    snapshot_id: 3055729675574597004,
                    timestamp_ms: 1555100955770,
                },
            ],
            metadata_log: Vec::new(),
            refs: HashMap::from_iter(vec![("main".to_string(), SnapshotReference {
                snapshot_id: 3055729675574597004,
                retention: SnapshotRetention::Branch {
                    min_snapshots_to_keep: None,
                    max_snapshot_age_ms: None,
                    max_ref_age_ms: None,
                },
            })]),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        check_table_metadata_serde(&metadata, expected);
    }

    #[test]
    fn test_table_metadata_v2_file_valid_minimal() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV2ValidMinimal.json").unwrap();

        let schema = Schema::builder()
            .with_schema_id(0)
            .with_fields(vec![
                Arc::new(NestedField::required(
                    1,
                    "x",
                    Type::Primitive(PrimitiveType::Long),
                )),
                Arc::new(
                    NestedField::required(2, "y", Type::Primitive(PrimitiveType::Long))
                        .with_doc("comment"),
                ),
                Arc::new(NestedField::required(
                    3,
                    "z",
                    Type::Primitive(PrimitiveType::Long),
                )),
            ])
            .build()
            .unwrap();

        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .add_unbound_field(
                UnboundPartitionField::builder()
                    .source_ids(vec![1])
                    .field_id(1000)
                    .name("x".to_string())
                    .transform(Transform::Identity)
                    .build()
                    .unwrap(),
            )
            .unwrap()
            .build()
            .unwrap();

        let sort_order = SortOrder::builder()
            .with_order_id(3)
            .with_sort_field(SortField {
                source_id: 2,
                transform: Transform::Identity,
                direction: SortDirection::Ascending,
                null_order: NullOrder::First,
            })
            .with_sort_field(SortField {
                source_id: 3,
                transform: Transform::Bucket(4),
                direction: SortDirection::Descending,
                null_order: NullOrder::Last,
            })
            .build_unbound()
            .unwrap();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V2,
            table_uuid: Uuid::parse_str("9c12d441-03fe-4693-9a96-a0705ddf69c1").unwrap(),
            location: "s3://bucket/test/location".to_string(),
            last_updated_ms: 1602638573590,
            last_column_id: 3,
            schemas: HashMap::from_iter(vec![(0, Arc::new(schema))]),
            current_schema_id: 0,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_partition_type,
            default_spec: Arc::new(partition_spec),
            last_partition_id: 1000,
            default_sort_order_id: 3,
            sort_orders: HashMap::from_iter(vec![(3, sort_order.into())]),
            snapshots: HashMap::default(),
            current_snapshot_id: None,
            last_sequence_number: 34,
            properties: HashMap::new(),
            snapshot_log: vec![],
            metadata_log: Vec::new(),
            refs: HashMap::new(),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        check_table_metadata_serde(&metadata, expected);
    }

    #[test]
    fn test_table_metadata_v1_file_valid() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV1Valid.json").unwrap();

        let schema = Schema::builder()
            .with_schema_id(0)
            .with_fields(vec![
                Arc::new(NestedField::required(
                    1,
                    "x",
                    Type::Primitive(PrimitiveType::Long),
                )),
                Arc::new(
                    NestedField::required(2, "y", Type::Primitive(PrimitiveType::Long))
                        .with_doc("comment"),
                ),
                Arc::new(NestedField::required(
                    3,
                    "z",
                    Type::Primitive(PrimitiveType::Long),
                )),
            ])
            .build()
            .unwrap();

        let partition_spec = PartitionSpec::builder(schema.clone())
            .with_spec_id(0)
            .add_unbound_field(
                UnboundPartitionField::builder()
                    .source_ids(vec![1])
                    .field_id(1000)
                    .name("x".to_string())
                    .transform(Transform::Identity)
                    .build()
                    .unwrap(),
            )
            .unwrap()
            .build()
            .unwrap();

        let default_partition_type = partition_spec.partition_type(&schema).unwrap();
        let expected = TableMetadata {
            format_version: FormatVersion::V1,
            table_uuid: Uuid::parse_str("d20125c8-7284-442c-9aea-15fee620737c").unwrap(),
            location: "s3://bucket/test/location".to_string(),
            last_updated_ms: 1602638573874,
            last_column_id: 3,
            schemas: HashMap::from_iter(vec![(0, Arc::new(schema))]),
            current_schema_id: 0,
            partition_specs: HashMap::from_iter(vec![(0, partition_spec.clone().into())]),
            default_spec: Arc::new(partition_spec),
            default_partition_type,
            last_partition_id: 0,
            default_sort_order_id: 0,
            // Sort order is added during deserialization for V2 compatibility
            sort_orders: HashMap::from_iter(vec![(0, SortOrder::unsorted_order().into())]),
            snapshots: HashMap::new(),
            current_snapshot_id: None,
            last_sequence_number: 0,
            properties: HashMap::new(),
            snapshot_log: vec![],
            metadata_log: Vec::new(),
            refs: HashMap::new(),
            statistics: HashMap::new(),
            partition_statistics: HashMap::new(),
            encryption_keys: HashMap::new(),
            next_row_id: INITIAL_ROW_ID,
        };

        check_table_metadata_serde(&metadata, expected);
    }

    #[test]
    fn test_empty_snapshot_id_is_normalized_to_none() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV1Valid.json").unwrap();
        let deserialized: TableMetadata = serde_json::from_str(&metadata).unwrap();
        assert_eq!(
            deserialized.current_snapshot_id(),
            None,
            "current_snapshot_id of -1 should be deserialized as None"
        );
    }

    #[test]
    fn test_table_metadata_v1_compat() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV1Compat.json").unwrap();

        // Deserialize the JSON to verify it works
        let desered_type: TableMetadata = serde_json::from_str(&metadata)
            .expect("Failed to deserialize TableMetadataV1Compat.json");

        // Verify some key fields match
        assert_eq!(desered_type.format_version(), FormatVersion::V1);
        assert_eq!(
            desered_type.uuid(),
            Uuid::parse_str("3276010d-7b1d-488c-98d8-9025fc4fde6b").unwrap()
        );
        assert_eq!(
            desered_type.location(),
            "s3://bucket/warehouse/iceberg/glue.db/table_name"
        );
        assert_eq!(desered_type.last_updated_ms(), 1727773114005);
        assert_eq!(desered_type.current_schema_id(), 0);
    }

    #[test]
    fn test_table_metadata_v1_schemas_without_current_id() {
        let metadata = fs::read_to_string(
            "testdata/table_metadata/TableMetadataV1SchemasWithoutCurrentId.json",
        )
        .unwrap();

        // Deserialize the JSON - this should succeed by using the 'schema' field instead of 'schemas'
        let desered_type: TableMetadata = serde_json::from_str(&metadata)
            .expect("Failed to deserialize TableMetadataV1SchemasWithoutCurrentId.json");

        // Verify it used the 'schema' field
        assert_eq!(desered_type.format_version(), FormatVersion::V1);
        assert_eq!(
            desered_type.uuid(),
            Uuid::parse_str("d20125c8-7284-442c-9aea-15fee620737c").unwrap()
        );

        // Get the schema and verify it has the expected fields
        let schema = desered_type.current_schema();
        assert_eq!(schema.as_struct().fields().len(), 3);
        assert_eq!(schema.as_struct().fields()[0].name, "x");
        assert_eq!(schema.as_struct().fields()[1].name, "y");
        assert_eq!(schema.as_struct().fields()[2].name, "z");
    }

    #[test]
    fn test_table_metadata_v1_no_valid_schema() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV1NoValidSchema.json")
                .unwrap();

        // Deserialize the JSON - this should fail because neither schemas + current_schema_id nor schema is valid
        let desered: Result<TableMetadata, serde_json::Error> = serde_json::from_str(&metadata);

        assert!(desered.is_err());
        let error_message = desered.unwrap_err().to_string();
        assert!(
            error_message.contains("No valid schema configuration found"),
            "Expected error about no valid schema configuration, got: {error_message}"
        );
    }

    #[test]
    fn test_table_metadata_v1_partition_specs_without_default_id() {
        let metadata = fs::read_to_string(
            "testdata/table_metadata/TableMetadataV1PartitionSpecsWithoutDefaultId.json",
        )
        .unwrap();

        // Deserialize the JSON - this should succeed by inferring default_spec_id as the max spec ID
        let desered_type: TableMetadata = serde_json::from_str(&metadata)
            .expect("Failed to deserialize TableMetadataV1PartitionSpecsWithoutDefaultId.json");

        // Verify basic metadata
        assert_eq!(desered_type.format_version(), FormatVersion::V1);
        assert_eq!(
            desered_type.uuid(),
            Uuid::parse_str("d20125c8-7284-442c-9aea-15fee620737c").unwrap()
        );

        // Verify partition specs
        assert_eq!(desered_type.default_partition_spec_id(), 2); // Should pick the largest spec ID (2)
        assert_eq!(desered_type.partition_specs.len(), 2);

        // Verify the default spec has the expected fields
        let default_spec = &desered_type.default_spec;
        assert_eq!(default_spec.spec_id(), 2);
        assert_eq!(default_spec.fields().len(), 1);
        assert_eq!(default_spec.fields()[0].name, "y");
        assert_eq!(default_spec.fields()[0].transform, Transform::Identity);
        assert_eq!(default_spec.fields()[0].source_id, 2);
    }

    #[test]
    fn test_table_metadata_v2_schema_not_found() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV2CurrentSchemaNotFound.json")
                .unwrap();

        let desered: Result<TableMetadata, serde_json::Error> = serde_json::from_str(&metadata);

        assert_eq!(
            desered.unwrap_err().to_string(),
            "DataInvalid => No schema exists with the current schema id 2."
        )
    }

    #[test]
    fn test_table_metadata_v2_missing_sort_order() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV2MissingSortOrder.json")
                .unwrap();

        let desered: Result<TableMetadata, serde_json::Error> = serde_json::from_str(&metadata);

        assert_eq!(
            desered.unwrap_err().to_string(),
            "data did not match any variant of untagged enum TableMetadataEnum"
        )
    }

    #[test]
    fn test_table_metadata_v2_missing_partition_specs() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV2MissingPartitionSpecs.json")
                .unwrap();

        let desered: Result<TableMetadata, serde_json::Error> = serde_json::from_str(&metadata);

        assert_eq!(
            desered.unwrap_err().to_string(),
            "data did not match any variant of untagged enum TableMetadataEnum"
        )
    }

    #[test]
    fn test_table_metadata_v2_missing_last_partition_id() {
        let metadata = fs::read_to_string(
            "testdata/table_metadata/TableMetadataV2MissingLastPartitionId.json",
        )
        .unwrap();

        let desered: Result<TableMetadata, serde_json::Error> = serde_json::from_str(&metadata);

        assert_eq!(
            desered.unwrap_err().to_string(),
            "data did not match any variant of untagged enum TableMetadataEnum"
        )
    }

    #[test]
    fn test_table_metadata_v2_missing_schemas() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataV2MissingSchemas.json")
                .unwrap();

        let desered: Result<TableMetadata, serde_json::Error> = serde_json::from_str(&metadata);

        assert_eq!(
            desered.unwrap_err().to_string(),
            "data did not match any variant of untagged enum TableMetadataEnum"
        )
    }

    #[test]
    fn test_table_metadata_v2_unsupported_version() {
        let metadata =
            fs::read_to_string("testdata/table_metadata/TableMetadataUnsupportedVersion.json")
                .unwrap();

        let desered: Result<TableMetadata, serde_json::Error> = serde_json::from_str(&metadata);

        assert_eq!(
            desered.unwrap_err().to_string(),
            "data did not match any variant of untagged enum TableMetadataEnum"
        )
    }

    #[test]
    fn test_order_of_format_version() {
        assert!(FormatVersion::V1 < FormatVersion::V2);
        assert_eq!(FormatVersion::V1, FormatVersion::V1);
        assert_eq!(FormatVersion::V2, FormatVersion::V2);
    }

    #[test]
    fn test_deserialize_default_partition_spec_with_dropped_source() {
        for version in [1, 2, 3] {
            for transform in ["identity", "truncate[4]", "bucket[16]"] {
                let mut metadata = serde_json::json!({
                    "format-version": version,
                    "table-uuid": "9c12d441-03fe-4693-9a96-a0705ddf69c1",
                    "location": "s3://bucket/table",
                    "last-sequence-number": 0,
                    "last-updated-ms": 1602638573590_i64,
                    "last-column-id": 2,
                    "current-schema-id": 1,
                    "schemas": [
                        {
                            "schema-id": 0,
                            "type": "struct",
                            "fields": [
                                {"id": 1, "name": "x", "required": false, "type": "long"},
                                {"id": 2, "name": "y", "required": false, "type": "long"}
                            ]
                        },
                        {
                            "schema-id": 1,
                            "type": "struct",
                            "fields": [
                                {"id": 2, "name": "y", "required": false, "type": "long"}
                            ]
                        }
                    ],
                    "default-spec-id": 0,
                    "partition-specs": [{"spec-id": 0, "fields": [{
                        "source-id": 1, "field-id": 1000, "name": "x_partition",
                        "transform": transform
                    }]}],
                    "last-partition-id": 1000,
                    "default-sort-order-id": 0,
                    "sort-orders": [{"order-id": 0, "fields": []}],
                    "next-row-id": 0
                });

                // Retaining the source in history does not make it writable using
                // the current schema and default spec.
                let err = serde_json::from_value::<TableMetadata>(metadata.clone()).unwrap_err();
                assert!(err.to_string().contains(
                    "Default partition spec 0 references missing source field 1 in current schema 1"
                ));

                // The same spec is allowed once it becomes historical.
                metadata["partition-specs"]
                    .as_array_mut()
                    .unwrap()
                    .push(serde_json::json!({"spec-id": 1, "fields": []}));
                metadata["default-spec-id"] = serde_json::json!(1);
                serde_json::from_value::<TableMetadata>(metadata.clone()).unwrap();

                // A voided field does not require its dropped source, even in the default spec.
                metadata["default-spec-id"] = serde_json::json!(0);
                metadata["partition-specs"][0]["fields"][0]["transform"] =
                    serde_json::json!("void");
                serde_json::from_value::<TableMetadata>(metadata).unwrap();
            }
        }
    }

    #[test]
    fn test_default_partition_spec() {
        let default_spec_id = 1234;
        let mut table_meta_data = get_test_table_metadata("TableMetadataV2Valid.json");
        let partition_spec = PartitionSpec::unpartition_spec();
        table_meta_data.default_spec = partition_spec.clone().into();
        table_meta_data
            .partition_specs
            .insert(default_spec_id, Arc::new(partition_spec));

        assert_eq!(
            (*table_meta_data.default_partition_spec().clone()).clone(),
            (*table_meta_data
                .partition_spec_by_id(default_spec_id)
                .unwrap()
                .clone())
            .clone()
        );
    }
    #[test]
    fn test_default_sort_order() {
        let default_sort_order_id = 1234;
        let mut table_meta_data = get_test_table_metadata("TableMetadataV2Valid.json");
        table_meta_data.default_sort_order_id = default_sort_order_id;
        table_meta_data
            .sort_orders
            .insert(default_sort_order_id, Arc::new(SortOrder::default()));

        assert_eq!(
            table_meta_data.default_sort_order(),
            table_meta_data
                .sort_orders
                .get(&default_sort_order_id)
                .unwrap()
        )
    }

    #[test]
    fn test_table_metadata_builder_from_table_creation() {
        let table_creation = TableCreation::builder()
            .location("s3://db/table".to_string())
            .name("table".to_string())
            .properties(HashMap::new())
            .schema(Schema::builder().build().unwrap())
            .build();
        let table_metadata = TableMetadataBuilder::from_table_creation(table_creation)
            .unwrap()
            .build()
            .unwrap()
            .metadata;
        assert_eq!(table_metadata.location, "s3://db/table");
        assert_eq!(table_metadata.schemas.len(), 1);
        assert_eq!(
            table_metadata
                .schemas
                .get(&0)
                .unwrap()
                .as_struct()
                .fields()
                .len(),
            0
        );
        assert_eq!(table_metadata.properties.len(), 0);
        assert_eq!(
            table_metadata.partition_specs,
            HashMap::from([(
                0,
                Arc::new(
                    PartitionSpec::builder(table_metadata.schemas.get(&0).unwrap().clone())
                        .with_spec_id(0)
                        .build()
                        .unwrap()
                )
            )])
        );
        assert_eq!(
            table_metadata.sort_orders,
            HashMap::from([(
                0,
                Arc::new(SortOrder {
                    order_id: 0,
                    fields: vec![]
                })
            )])
        );
    }

    #[tokio::test]
    async fn test_table_metadata_read_write() {
        // Create a temporary directory for our test
        let temp_dir = TempDir::new().unwrap();
        let temp_path = temp_dir.path().to_str().unwrap();

        // Create a FileIO instance
        let file_io = FileIO::new_with_fs();

        // Use an existing test metadata from the test files
        let original_metadata: TableMetadata =
            get_test_table_metadata_at("TableMetadataV2Valid.json", temp_path);

        // Define the metadata location
        let metadata_location =
            MetadataLocation::try_new_with_metadata(&original_metadata).unwrap();
        let metadata_location_str = metadata_location.to_string();

        // Write the metadata
        original_metadata
            .write_to(&file_io, &metadata_location)
            .await
            .unwrap();

        // Verify the file exists
        assert!(fs::metadata(&metadata_location_str).is_ok());

        // Read the metadata back
        let read_metadata = TableMetadata::read_from(&file_io, &metadata_location_str)
            .await
            .unwrap();

        // Verify the metadata matches
        assert_eq!(read_metadata, original_metadata);
    }

    #[tokio::test]
    async fn test_table_metadata_read_compressed() {
        let temp_dir = TempDir::new().unwrap();
        let metadata_location = temp_dir.path().join("v1.gz.metadata.json");

        let original_metadata: TableMetadata = get_test_table_metadata("TableMetadataV2Valid.json");
        let json = serde_json::to_string(&original_metadata).unwrap();

        let compressed = CompressionCodec::gzip_default()
            .compress(json.into_bytes())
            .expect("failed to compress metadata");
        fs::write(&metadata_location, &compressed).expect("failed to write metadata");

        // Read the metadata back
        let file_io = FileIO::new_with_fs();
        let metadata_location = metadata_location.to_str().unwrap();
        let read_metadata = TableMetadata::read_from(&file_io, metadata_location)
            .await
            .unwrap();

        // Verify the metadata matches
        assert_eq!(read_metadata, original_metadata);
    }

    #[tokio::test]
    async fn test_table_metadata_read_nonexistent_file() {
        // Create a FileIO instance
        let file_io = FileIO::new_with_fs();

        // Try to read a non-existent file
        let result = TableMetadata::read_from(&file_io, "/nonexistent/path/metadata.json").await;

        // Verify it returns an error
        assert!(result.is_err());
    }

    #[tokio::test]
    async fn test_table_metadata_write_with_gzip_compression() {
        let temp_dir = TempDir::new().unwrap();
        let temp_path = temp_dir.path().to_str().unwrap();
        let file_io = FileIO::new_with_fs();

        // Get a test metadata and add gzip compression property
        let original_metadata: TableMetadata =
            get_test_table_metadata_at("TableMetadataV2Valid.json", temp_path);

        // Modify properties to enable gzip compression (using mixed case to test case-insensitive matching)
        let mut props = original_metadata.properties.clone();
        props.insert(
            TableProperties::PROPERTY_METADATA_COMPRESSION_CODEC.to_string(),
            "GziP".to_string(),
        );
        // Use builder to create new metadata with updated properties
        let compressed_metadata =
            TableMetadataBuilder::new_from_metadata(original_metadata.clone(), None)
                .assign_uuid(original_metadata.table_uuid)
                .set_properties(props.clone())
                .unwrap()
                .build()
                .unwrap()
                .metadata;

        // Create MetadataLocation with compression codec from metadata
        let metadata_location =
            MetadataLocation::try_new_with_metadata(&compressed_metadata).unwrap();
        let metadata_location_str = metadata_location.to_string();

        // Verify the location has the .gz extension
        assert!(metadata_location_str.contains(".gz.metadata.json"));

        // Write the metadata with compression
        compressed_metadata
            .write_to(&file_io, &metadata_location)
            .await
            .unwrap();

        // Verify the compressed file exists
        assert!(std::path::Path::new(&metadata_location_str).exists());

        // Read the raw file and check it's gzip compressed
        let raw_content = fs::read(&metadata_location_str).unwrap();
        assert!(raw_content.len() > 2);
        assert_eq!(raw_content[0], 0x1F); // gzip magic number
        assert_eq!(raw_content[1], 0x8B); // gzip magic number

        // Read the metadata back using the compressed location
        let read_metadata = TableMetadata::read_from(&file_io, &metadata_location_str)
            .await
            .unwrap();

        // Verify the complete round-trip: read metadata should match what we wrote
        assert_eq!(read_metadata, compressed_metadata);
    }

    #[test]
    fn test_partition_name_exists() {
        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "data", Type::Primitive(PrimitiveType::String)).into(),
                NestedField::required(2, "partition_col", Type::Primitive(PrimitiveType::Int))
                    .into(),
            ])
            .build()
            .unwrap();

        let spec1 = PartitionSpec::builder(schema.clone())
            .with_spec_id(1)
            .add_partition_field("data", "data_partition", Transform::Identity)
            .unwrap()
            .build()
            .unwrap();

        let spec2 = PartitionSpec::builder(schema.clone())
            .with_spec_id(2)
            .add_partition_field("partition_col", "partition_bucket", Transform::Bucket(16))
            .unwrap()
            .build()
            .unwrap();

        // Build metadata with these specs
        let metadata = TableMetadataBuilder::new(
            schema,
            spec1.clone().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap()
        .add_partition_spec(spec2.into_unbound())
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        assert!(metadata.partition_name_exists("data_partition"));
        assert!(metadata.partition_name_exists("partition_bucket"));

        assert!(!metadata.partition_name_exists("nonexistent_field"));
        assert!(!metadata.partition_name_exists("data")); // schema field name, not partition field name
        assert!(!metadata.partition_name_exists(""));
    }

    #[test]
    fn test_partition_name_exists_empty_specs() {
        // Create metadata with no partition specs (unpartitioned table)
        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "data", Type::Primitive(PrimitiveType::String)).into(),
            ])
            .build()
            .unwrap();

        let metadata = TableMetadataBuilder::new(
            schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        assert!(!metadata.partition_name_exists("any_field"));
        assert!(!metadata.partition_name_exists("data"));
    }

    #[test]
    fn test_name_exists_in_any_schema() {
        // Create multiple schemas with different fields
        let schema1 = Schema::builder()
            .with_schema_id(1)
            .with_fields(vec![
                NestedField::required(1, "field1", Type::Primitive(PrimitiveType::String)).into(),
                NestedField::required(2, "field2", Type::Primitive(PrimitiveType::Int)).into(),
            ])
            .build()
            .unwrap();

        let schema2 = Schema::builder()
            .with_schema_id(2)
            .with_fields(vec![
                NestedField::required(1, "field1", Type::Primitive(PrimitiveType::String)).into(),
                NestedField::required(3, "field3", Type::Primitive(PrimitiveType::Long)).into(),
            ])
            .build()
            .unwrap();

        let metadata = TableMetadataBuilder::new(
            schema1,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap()
        .add_current_schema(schema2)
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        assert!(metadata.name_exists_in_any_schema("field1")); // exists in both schemas
        assert!(metadata.name_exists_in_any_schema("field2")); // exists only in schema1 (historical)
        assert!(metadata.name_exists_in_any_schema("field3")); // exists only in schema2 (current)

        assert!(!metadata.name_exists_in_any_schema("nonexistent_field"));
        assert!(!metadata.name_exists_in_any_schema("field4"));
        assert!(!metadata.name_exists_in_any_schema(""));
    }

    #[test]
    fn test_name_exists_in_any_schema_empty_schemas() {
        let schema = Schema::builder().with_fields(vec![]).build().unwrap();

        let metadata = TableMetadataBuilder::new(
            schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        assert!(!metadata.name_exists_in_any_schema("any_field"));
    }

    #[test]
    fn test_helper_methods_multi_version_scenario() {
        // Test a realistic multi-version scenario
        let initial_schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
                NestedField::required(2, "name", Type::Primitive(PrimitiveType::String)).into(),
                NestedField::required(
                    3,
                    "deprecated_field",
                    Type::Primitive(PrimitiveType::String),
                )
                .into(),
            ])
            .build()
            .unwrap();

        let metadata = TableMetadataBuilder::new(
            initial_schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap();

        let evolved_schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
                NestedField::required(2, "name", Type::Primitive(PrimitiveType::String)).into(),
                NestedField::required(
                    3,
                    "deprecated_field",
                    Type::Primitive(PrimitiveType::String),
                )
                .into(),
                NestedField::required(4, "new_field", Type::Primitive(PrimitiveType::Double))
                    .into(),
            ])
            .build()
            .unwrap();

        // Then add a third schema that removes the deprecated field
        let _final_schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
                NestedField::required(2, "name", Type::Primitive(PrimitiveType::String)).into(),
                NestedField::required(4, "new_field", Type::Primitive(PrimitiveType::Double))
                    .into(),
                NestedField::required(5, "latest_field", Type::Primitive(PrimitiveType::Boolean))
                    .into(),
            ])
            .build()
            .unwrap();

        let final_metadata = metadata
            .add_current_schema(evolved_schema)
            .unwrap()
            .build()
            .unwrap()
            .metadata;

        assert!(!final_metadata.partition_name_exists("nonexistent_partition")); // unpartitioned table

        assert!(final_metadata.name_exists_in_any_schema("id")); // exists in both schemas
        assert!(final_metadata.name_exists_in_any_schema("name")); // exists in both schemas
        assert!(final_metadata.name_exists_in_any_schema("deprecated_field")); // exists in both schemas
        assert!(final_metadata.name_exists_in_any_schema("new_field")); // only in current schema
        assert!(!final_metadata.name_exists_in_any_schema("never_existed"));
    }

    #[test]
    fn test_invalid_sort_order_id_zero_with_fields() {
        let metadata = r#"
        {
            "format-version": 2,
            "table-uuid": "9c12d441-03fe-4693-9a96-a0705ddf69c1",
            "location": "s3://bucket/test/location",
            "last-sequence-number": 111,
            "last-updated-ms": 1600000000000,
            "last-column-id": 3,
            "current-schema-id": 1,
            "schemas": [
                {
                    "type": "struct",
                    "schema-id": 1,
                    "fields": [
                        {"id": 1, "name": "x", "required": true, "type": "long"},
                        {"id": 2, "name": "y", "required": true, "type": "long"}
                    ]
                }
            ],
            "default-spec-id": 0,
            "partition-specs": [{"spec-id": 0, "fields": []}],
            "last-partition-id": 999,
            "default-sort-order-id": 0,
            "sort-orders": [
                {
                    "order-id": 0,
                    "fields": [
                        {
                            "transform": "identity",
                            "source-id": 1,
                            "direction": "asc",
                            "null-order": "nulls-first"
                        }
                    ]
                }
            ],
            "properties": {},
            "current-snapshot-id": -1,
            "snapshots": []
        }
        "#;

        let result: Result<TableMetadata, serde_json::Error> = serde_json::from_str(metadata);

        // Should fail because sort order ID 0 is reserved for unsorted order and cannot have fields
        assert!(
            result.is_err(),
            "Parsing should fail for sort order ID 0 with fields"
        );
    }

    #[test]
    fn test_table_properties_with_defaults() {
        use crate::spec::TableProperties;

        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
            ])
            .build()
            .unwrap();

        let metadata = TableMetadataBuilder::new(
            schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        let props = metadata.table_properties();

        assert_eq!(
            props.commit_num_retries().unwrap(),
            TableProperties::PROPERTY_COMMIT_NUM_RETRIES_DEFAULT
        );
        assert_eq!(
            props.write_target_file_size_bytes().unwrap(),
            TableProperties::PROPERTY_WRITE_TARGET_FILE_SIZE_BYTES_DEFAULT
        );
    }

    #[test]
    fn test_table_properties_with_custom_values() {
        use crate::spec::TableProperties;

        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
            ])
            .build()
            .unwrap();

        let properties = HashMap::from([
            (
                TableProperties::PROPERTY_COMMIT_NUM_RETRIES.to_string(),
                "10".to_string(),
            ),
            (
                TableProperties::PROPERTY_WRITE_TARGET_FILE_SIZE_BYTES.to_string(),
                "1024".to_string(),
            ),
        ]);

        let metadata = TableMetadataBuilder::new(
            schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            properties,
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        let props = metadata.table_properties();

        assert_eq!(props.commit_num_retries().unwrap(), 10);
        assert_eq!(props.write_target_file_size_bytes().unwrap(), 1024);
    }

    #[test]
    fn test_deserialize_metadata_defers_invalid_table_property_errors() {
        let invalid_retries = "not_a_number";
        let invalid_codec = "unknown";
        let target_file_size = "1024";

        for file_name in [
            "TableMetadataV1Valid.json",
            "TableMetadataV2ValidMinimal.json",
            "TableMetadataV3ValidMinimal.json",
        ] {
            let path = format!("testdata/table_metadata/{file_name}");
            let mut json: serde_json::Value =
                serde_json::from_str(&fs::read_to_string(path).unwrap()).unwrap();
            json["properties"] = serde_json::json!({
                (TableProperties::PROPERTY_COMMIT_NUM_RETRIES): invalid_retries,
                (TableProperties::PROPERTY_METADATA_COMPRESSION_CODEC): invalid_codec,
                (TableProperties::PROPERTY_WRITE_TARGET_FILE_SIZE_BYTES): target_file_size,
            });

            let metadata: TableMetadata = serde_json::from_value(json).unwrap();
            assert_eq!(
                metadata
                    .properties()
                    .get(TableProperties::PROPERTY_COMMIT_NUM_RETRIES)
                    .map(String::as_str),
                Some(invalid_retries)
            );

            let table_properties = metadata.table_properties();
            let error = table_properties.commit_num_retries().unwrap_err();
            assert!(
                error
                    .message()
                    .contains(TableProperties::PROPERTY_COMMIT_NUM_RETRIES)
            );
            assert_eq!(
                table_properties.write_target_file_size_bytes().unwrap(),
                1024
            );
            let error = table_properties.metadata_compression_codec().unwrap_err();
            assert!(
                format!("{error}").contains(TableProperties::PROPERTY_METADATA_COMPRESSION_CODEC)
            );

            let serialized = serde_json::to_value(metadata).unwrap();
            assert_eq!(
                serialized["properties"][TableProperties::PROPERTY_COMMIT_NUM_RETRIES],
                invalid_retries
            );
            assert_eq!(
                serialized["properties"][TableProperties::PROPERTY_METADATA_COMPRESSION_CODEC],
                invalid_codec
            );
        }
    }

    #[test]
    fn test_table_properties_with_invalid_value() {
        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
            ])
            .build()
            .unwrap();

        let properties = HashMap::from([
            (
                TableProperties::PROPERTY_COMMIT_NUM_RETRIES.to_string(),
                "not_a_number".to_string(),
            ),
            (
                TableProperties::PROPERTY_WRITE_TARGET_FILE_SIZE_BYTES.to_string(),
                "1024".to_string(),
            ),
        ]);

        let metadata = TableMetadataBuilder::new(
            schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://test/location".to_string(),
            FormatVersion::V2,
            properties,
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        let table_properties = metadata.table_properties();
        let err = table_properties.commit_num_retries().unwrap_err();
        assert_eq!(err.kind(), ErrorKind::DataInvalid);
        assert!(
            err.message()
                .contains(TableProperties::PROPERTY_COMMIT_NUM_RETRIES)
        );
        assert_eq!(
            table_properties.write_target_file_size_bytes().unwrap(),
            1024
        );
    }

    #[test]
    fn test_v2_to_v3_upgrade_preserves_existing_snapshots_without_row_lineage() {
        // Create a v2 table metadata
        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
            ])
            .build()
            .unwrap();

        let v2_metadata = TableMetadataBuilder::new(
            schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://bucket/test/location".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        // Add a v2 snapshot
        let snapshot = Snapshot::builder()
            .with_snapshot_id(1)
            .with_timestamp_ms(v2_metadata.last_updated_ms + 1)
            .with_sequence_number(1)
            .with_schema_id(0)
            .with_manifest_list("s3://bucket/test/metadata/snap-1.avro")
            .with_summary(Summary {
                operation: Operation::Append,
                additional_properties: HashMap::from([(
                    "added-data-files".to_string(),
                    "1".to_string(),
                )]),
            })
            .build();

        let v2_with_snapshot = v2_metadata
            .into_builder(Some("s3://bucket/test/metadata/v00001.json".to_string()))
            .add_snapshot(snapshot)
            .unwrap()
            .set_ref("main", SnapshotReference {
                snapshot_id: 1,
                retention: SnapshotRetention::Branch {
                    min_snapshots_to_keep: None,
                    max_snapshot_age_ms: None,
                    max_ref_age_ms: None,
                },
            })
            .unwrap()
            .build()
            .unwrap()
            .metadata;

        // Verify v2 serialization works fine
        let v2_json = serde_json::to_string(&v2_with_snapshot);
        assert!(v2_json.is_ok(), "v2 serialization should work");

        // Upgrade to v3
        let v3_metadata = v2_with_snapshot
            .into_builder(Some("s3://bucket/test/metadata/v00002.json".to_string()))
            .upgrade_format_version(FormatVersion::V3)
            .unwrap()
            .build()
            .unwrap()
            .metadata;

        assert_eq!(v3_metadata.format_version, FormatVersion::V3);
        assert_eq!(v3_metadata.next_row_id, INITIAL_ROW_ID);
        assert_eq!(v3_metadata.snapshots.len(), 1);

        // Verify the snapshot has no row_range
        let snapshot = v3_metadata.snapshots.values().next().unwrap();
        assert!(
            snapshot.row_range().is_none(),
            "Snapshot should have no row_range after upgrade"
        );

        // Try to serialize v3 metadata - this should now work
        let v3_json = serde_json::to_string(&v3_metadata);
        assert!(
            v3_json.is_ok(),
            "v3 serialization should work for upgraded tables"
        );

        // Verify we can deserialize it back
        let deserialized: TableMetadata = serde_json::from_str(&v3_json.unwrap()).unwrap();
        assert_eq!(deserialized.format_version, FormatVersion::V3);
        assert_eq!(deserialized.snapshots.len(), 1);

        // Verify the deserialized snapshot still has no row_range
        let deserialized_snapshot = deserialized.snapshots.values().next().unwrap();
        assert!(
            deserialized_snapshot.row_range().is_none(),
            "Deserialized snapshot should have no row_range"
        );
    }

    #[test]
    fn test_v3_snapshot_with_row_lineage_serialization() {
        // Create a v3 table metadata
        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "id", Type::Primitive(PrimitiveType::Long)).into(),
            ])
            .build()
            .unwrap();

        let v3_metadata = TableMetadataBuilder::new(
            schema,
            PartitionSpec::unpartition_spec().into_unbound(),
            SortOrder::unsorted_order(),
            "s3://bucket/test/location".to_string(),
            FormatVersion::V3,
            HashMap::new(),
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        // Add a v3 snapshot with row lineage
        let snapshot = Snapshot::builder()
            .with_snapshot_id(1)
            .with_timestamp_ms(v3_metadata.last_updated_ms + 1)
            .with_sequence_number(1)
            .with_schema_id(0)
            .with_manifest_list("s3://bucket/test/metadata/snap-1.avro")
            .with_summary(Summary {
                operation: Operation::Append,
                additional_properties: HashMap::from([(
                    "added-data-files".to_string(),
                    "1".to_string(),
                )]),
            })
            .with_row_range(100, 50) // first_row_id=100, added_rows=50
            .build();

        let v3_with_snapshot = v3_metadata
            .into_builder(Some("s3://bucket/test/metadata/v00001.json".to_string()))
            .add_snapshot(snapshot)
            .unwrap()
            .set_ref("main", SnapshotReference {
                snapshot_id: 1,
                retention: SnapshotRetention::Branch {
                    min_snapshots_to_keep: None,
                    max_snapshot_age_ms: None,
                    max_ref_age_ms: None,
                },
            })
            .unwrap()
            .build()
            .unwrap()
            .metadata;

        // Verify the snapshot has row_range
        let snapshot = v3_with_snapshot.snapshots.values().next().unwrap();
        assert!(
            snapshot.row_range().is_some(),
            "Snapshot should have row_range"
        );
        let (first_row_id, added_rows) = snapshot.row_range().unwrap();
        assert_eq!(first_row_id, 100);
        assert_eq!(added_rows, 50);

        // Serialize v3 metadata - this should work
        let v3_json = serde_json::to_string(&v3_with_snapshot);
        assert!(
            v3_json.is_ok(),
            "v3 serialization should work for snapshots with row lineage"
        );

        // Verify we can deserialize it back
        let deserialized: TableMetadata = serde_json::from_str(&v3_json.unwrap()).unwrap();
        assert_eq!(deserialized.format_version, FormatVersion::V3);
        assert_eq!(deserialized.snapshots.len(), 1);

        // Verify the deserialized snapshot has the correct row_range
        let deserialized_snapshot = deserialized.snapshots.values().next().unwrap();
        assert!(
            deserialized_snapshot.row_range().is_some(),
            "Deserialized snapshot should have row_range"
        );
        let (deserialized_first_row_id, deserialized_added_rows) =
            deserialized_snapshot.row_range().unwrap();
        assert_eq!(deserialized_first_row_id, 100);
        assert_eq!(deserialized_added_rows, 50);
    }

    #[test]
    fn test_metadata_location_default() {
        // Verify metadata files go to `<location>/metadata` when `write.metadata.path` is not set
        let metadata = get_test_table_metadata("TableMetadataV2Valid.json");
        assert_eq!(metadata.location(), "s3://bucket/test/location");
        assert_eq!(
            metadata.metadata_location().unwrap(),
            "s3://bucket/test/location/metadata"
        );
    }

    #[test]
    fn test_metadata_location_honors_write_metadata_path() {
        let metadata = get_test_table_metadata("TableMetadataV2Valid.json")
            .into_builder(None)
            .set_properties(HashMap::from([(
                TableProperties::PROPERTY_WRITE_METADATA_PATH.to_string(),
                "s3://other-bucket/custom-meta".to_string(),
            )]))
            .unwrap()
            .build()
            .unwrap()
            .metadata;
        assert_eq!(
            metadata.metadata_location().unwrap(),
            "s3://other-bucket/custom-meta"
        );
    }

    #[test]
    fn test_metadata_location_trims_trailing_slash() {
        // A configured path with a trailing slash must not yield a doubled separator
        let metadata = get_test_table_metadata("TableMetadataV2Valid.json")
            .into_builder(None)
            .set_properties(HashMap::from([(
                TableProperties::PROPERTY_WRITE_METADATA_PATH.to_string(),
                "s3://other-bucket/custom-meta/".to_string(),
            )]))
            .unwrap()
            .build()
            .unwrap()
            .metadata;
        assert_eq!(
            metadata.metadata_location().unwrap(),
            "s3://other-bucket/custom-meta"
        );
    }

    #[test]
    fn test_unified_partition_type_spans_all_specs() {
        let schema = Schema::builder()
            .with_fields(vec![
                NestedField::required(1, "x", Type::Primitive(PrimitiveType::Long)).into(),
                NestedField::required(2, "y", Type::Primitive(PrimitiveType::Long)).into(),
                NestedField::required(3, "z", Type::Primitive(PrimitiveType::Long)).into(),
            ])
            .build()
            .unwrap();

        let metadata = TableMetadataBuilder::new(
            schema.clone(),
            UnboundPartitionSpec::builder()
                .with_spec_id(0)
                .add_partition_field(
                    UnboundPartitionField::builder()
                        .source_ids(vec![2])
                        .name("y")
                        .transform(Transform::Identity)
                        .build()
                        .unwrap(),
                )
                .unwrap()
                .build(),
            SortOrder::unsorted_order(),
            "s3://bucket/table".to_string(),
            FormatVersion::V2,
            HashMap::new(),
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata
        .into_builder(None)
        .add_partition_spec(
            UnboundPartitionSpec::builder()
                .add_partition_field(
                    UnboundPartitionField::builder()
                        .source_ids(vec![3])
                        .name("z")
                        .transform(Transform::Identity)
                        .build()
                        .unwrap(),
                )
                .unwrap()
                .build(),
        )
        .unwrap()
        .build()
        .unwrap()
        .metadata;

        // The default spec only knows about `y`, but `_partition` must expose both.
        assert_eq!(metadata.default_partition_type().fields().len(), 1);

        let unified = metadata.unified_partition_type(&schema).unwrap();
        let names: Vec<&str> = unified
            .fields()
            .iter()
            .map(|field| field.name.as_str())
            .collect();
        assert_eq!(names, vec!["y", "z"]);
    }
}