HypertableOperationGeneratorTests.cs

using CmdScale.EntityFrameworkCore.TimescaleDB.Generators;
using CmdScale.EntityFrameworkCore.TimescaleDB.Operations;
using Microsoft.EntityFrameworkCore.Infrastructure;
using CmdScale.EntityFrameworkCore.TimescaleDB.Tests.Utils;
using CmdScale.EntityFrameworkCore.TimescaleDB.Abstractions;

namespace CmdScale.EntityFrameworkCore.TimescaleDB.Tests.Generators
{
    public class HypertableOperationGeneratorTests
    {
        /// <summary>
        /// A helper to run the generator and capture its string output.
        /// </summary>
        private static string GetGeneratedCode(dynamic operation)
        {
            IndentedStringBuilder builder = new();

            HypertableOperationGenerator generator = new(true);
            List<string> statements = generator.Generate(operation);
            SqlBuilderHelper.BuildQueryString(statements, builder);
            return builder.ToString();
        }

        // --- Tests for CreateHypertableOperation ---

        [Fact]
        public void Generate_Create_with_minimal_details_generates_correct_sql()
        {
            // Arrange
            CreateHypertableOperation operation = new()
            {
                TableName = "MinimalTable",
                Schema = "public",
                TimeColumnName = "Timestamp"
            };

            string expected = @".Sql(@""
                SELECT create_hypertable('public.""""MinimalTable""""', 'Timestamp');
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Create_with_all_options_generates_comprehensive_sql()
        {
            // Arrange
            CreateHypertableOperation operation = new()
            {
                TableName = "FullTable",
                Schema = "custom_schema",
                TimeColumnName = "EventTime",
                ChunkTimeInterval = "1 day",
                EnableCompression = true,
                ChunkSkipColumns = ["DeviceId"],
                AdditionalDimensions =
                [
                    Dimension.CreateHash("LocationId", 4)
                ]
            };

            string expected = @".Sql(@""
                SELECT create_hypertable('custom_schema.""""FullTable""""', 'EventTime', chunk_time_interval => INTERVAL '1 day');
                SELECT add_dimension('custom_schema.""""FullTable""""', by_hash('LocationId', 4));
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"custom_schema"""".""""FullTable"""" SET (timescaledb.compress = true)';
                        EXECUTE 'SET timescaledb.enable_chunk_skipping = ''ON''';
                        EXECUTE 'SELECT enable_chunk_skipping(''custom_schema.""""FullTable""""'', ''DeviceId'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Alter_WhenAddingChunkSkippingToUncompressedTable_ShouldAlsoEnableCompression()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "Metrics",
                Schema = "custom_schema",
                OldEnableCompression = false,
                OldChunkSkipColumns = [],
                EnableCompression = false,
                ChunkSkipColumns = ["device_id"]
            };

            string expected = @".Sql(@""
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"custom_schema"""".""""Metrics"""" SET (timescaledb.compress = true)';
                        EXECUTE 'SET timescaledb.enable_chunk_skipping = ''ON''';
                        EXECUTE 'SELECT enable_chunk_skipping(''custom_schema.""""Metrics""""'', ''device_id'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        // --- Tests for AlterHypertableOperation ---

        [Fact]
        public void Generate_Alter_when_changing_compression_generates_correct_sql()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "SensorData",
                Schema = "public",
                EnableCompression = true,
                OldEnableCompression = false
            };

            string expected = @".Sql(@""
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"public"""".""""SensorData"""" SET (timescaledb.compress = true)';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Create_With_Compression_Segment_And_OrderBy_Generates_Correct_Sql()
        {
            // Arrange
            CreateHypertableOperation operation = new()
            {
                TableName = "CompressedTable",
                Schema = "public",
                TimeColumnName = "Timestamp",
                EnableCompression = true,
                CompressionSegmentBy = ["TenantId", "DeviceId"],
                CompressionOrderBy = ["Timestamp DESC", "Value ASC NULLS LAST"]
            };

            // Expected: implicit compress=true, plus segmentby/orderby strings
            string expected = @".Sql(@""
                SELECT create_hypertable('public.""""CompressedTable""""', 'Timestamp');
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"public"""".""""CompressedTable"""" SET (timescaledb.compress = true, timescaledb.compress_segmentby = ''""""TenantId"""", """"DeviceId""""'', timescaledb.compress_orderby = ''""""Timestamp"""" DESC, """"Value"""" ASC NULLS LAST'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Alter_Adding_Compression_SegmentBy_Generates_Correct_Sql()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "Metrics",
                Schema = "public",
                // Adding segment by configuration
                CompressionSegmentBy = ["DeviceId"],
                OldCompressionSegmentBy = []
            };

            string expected = @".Sql(@""
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"public"""".""""Metrics"""" SET (timescaledb.compress = true, timescaledb.compress_segmentby = ''""""DeviceId""""'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Alter_Modifying_Compression_OrderBy_Generates_Correct_Sql()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "Metrics",
                Schema = "public",
                // Changing from ASC to DESC
                CompressionOrderBy = ["Timestamp DESC"],
                OldCompressionOrderBy = ["Timestamp ASC"]
            };

            string expected = @".Sql(@""
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"public"""".""""Metrics"""" SET (timescaledb.compress_orderby = ''""""Timestamp"""" DESC'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Alter_Removing_Compression_Configuration_Generates_Empty_Strings()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "Metrics",
                Schema = "public",
                EnableCompression = true,
                OldEnableCompression = true,

                // Removing both settings
                CompressionSegmentBy = [],
                OldCompressionSegmentBy = ["DeviceId"],
                CompressionOrderBy = null,
                OldCompressionOrderBy = ["Timestamp DESC"]
            };

            // TimescaleDB requires setting the value to '' (empty string) to clear it
            string expected = @".Sql(@""
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"public"""".""""Metrics"""" SET (timescaledb.compress_segmentby = '''', timescaledb.compress_orderby = '''')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Alter_when_adding_and_removing_skip_columns_generates_correct_sql()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "Metrics",
                Schema = "metrics_schema",
                ChunkSkipColumns = ["host", "service"],
                OldChunkSkipColumns = ["host", "region"]
            };

            string expected = @".Sql(@""
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'SET timescaledb.enable_chunk_skipping = ''ON''';
                        EXECUTE 'SELECT enable_chunk_skipping(''metrics_schema.""""Metrics""""'', ''service'')';
                        EXECUTE 'SELECT disable_chunk_skipping(''metrics_schema.""""Metrics""""'', ''region'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Alter_when_no_properties_change_generates_no_sql()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "NoChangeTable",
                Schema = "public",
                EnableCompression = true,
                OldEnableCompression = true,
                ChunkTimeInterval = "7 days",
                OldChunkTimeInterval = "7 days"
            };

            string expected = "";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(expected, result);
        }

        [Fact]
        public void Generate_Alter_WhenRemovingLastChunkSkipColumn_ShouldDisableCompression_IfNotExplicitlyEnabled()
        {
            // Arrange
            AlterHypertableOperation operation = new()
            {
                TableName = "Logs",
                Schema = "public",
                OldEnableCompression = false,
                OldChunkSkipColumns = ["trace_id"],
                EnableCompression = false,
                ChunkSkipColumns = []
            };
            string expected = @".Sql(@""
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"public"""".""""Logs"""" SET (timescaledb.compress = false)';
                        EXECUTE 'SELECT disable_chunk_skipping(''public.""""Logs""""'', ''trace_id'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        // --- Tests for MigrateData Parameter ---

        [Fact]
        public void Generate_Create_When_MigrateData_Is_False_Does_Not_Include_Migrate_Data_Parameter()
        {
            // Arrange
            CreateHypertableOperation operation = new()
            {
                TableName = "Metrics",
                Schema = "public",
                TimeColumnName = "Timestamp",
                MigrateData = false
            };

            string expected = @".Sql(@""
                SELECT create_hypertable('public.""""Metrics""""', 'Timestamp');
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Create_When_MigrateData_Is_True_Includes_Migrate_Data_Parameter()
        {
            // Arrange
            CreateHypertableOperation operation = new()
            {
                TableName = "Metrics",
                Schema = "public",
                TimeColumnName = "Timestamp",
                MigrateData = true
            };

            string expected = @".Sql(@""
                SELECT create_hypertable('public.""""Metrics""""', 'Timestamp', migrate_data => true);
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Create_When_MigrateData_True_With_All_Options_Generates_Comprehensive_Sql()
        {
            // Arrange
            CreateHypertableOperation operation = new()
            {
                TableName = "CompleteTable",
                Schema = "custom_schema",
                TimeColumnName = "EventTime",
                MigrateData = true,
                ChunkTimeInterval = "1 day",
                EnableCompression = true,
                ChunkSkipColumns = ["DeviceId"],
                AdditionalDimensions =
                [
                    Dimension.CreateHash("LocationId", 4)
                ]
            };

            string expected = @".Sql(@""
                SELECT create_hypertable('custom_schema.""""CompleteTable""""', 'EventTime', migrate_data => true, chunk_time_interval => INTERVAL '1 day');
                SELECT add_dimension('custom_schema.""""CompleteTable""""', by_hash('LocationId', 4));
                DO $$
                DECLARE
                    license TEXT;
                BEGIN
                    license := current_setting('timescaledb.license', true);

                    IF license IS NULL OR license != 'apache' THEN
                        EXECUTE 'ALTER TABLE """"custom_schema"""".""""CompleteTable"""" SET (timescaledb.compress = true)';
                        EXECUTE 'SET timescaledb.enable_chunk_skipping = ''ON''';
                        EXECUTE 'SELECT enable_chunk_skipping(''custom_schema.""""CompleteTable""""'', ''DeviceId'')';
                    ELSE
                        RAISE WARNING 'Skipping Community Edition features (compression, chunk skipping) - not available in Apache Edition';
                    END IF;
                END $$;
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
        }

        [Fact]
        public void Generate_Create_Default_MigrateData_Does_Not_Include_Parameter()
        {
            // Arrange - CreateHypertableOperation with default MigrateData (false)
            CreateHypertableOperation operation = new()
            {
                TableName = "DefaultTable",
                Schema = "public",
                TimeColumnName = "Timestamp"
                // MigrateData not explicitly set, defaults to false
            };

            string expected = @".Sql(@""
                SELECT create_hypertable('public.""""DefaultTable""""', 'Timestamp');
            "")";

            // Act
            string result = GetGeneratedCode(operation);

            // Assert
            Assert.Equal(SqlHelper.NormalizeSql(expected), SqlHelper.NormalizeSql(result));
            Assert.DoesNotContain("migrate_data", result);
        }
    }
}