sql-utilities/tests/Strata.SqlTools.LinqToSql.Tests/LinqQueryBreakdownTests.cs

using Strata.SqlTools.Breakdowns.LinqToSql;
using Strata.SqlTools.Breakdowns.SqlServer;

namespace Strata.SqlTools.LinqToSql.Tests;

[TestFixture]
public class LinqQueryBreakdownTests
{
    private TestDataContext _context = null!;
    private static readonly string[] separator = new[] { "AND" };

    [SetUp]
    public void Setup()
    {
        _context = new TestDataContext();
    }

    [Test]
    public void Analyze_SimpleSelectQuery_ExtractsCorrectClauses()
    {
        // Arrange
        var query = from user in TestDataContext.Users
                    select user;

        // Act
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Assert
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(breakdown.EntityType, Is.EqualTo(typeof(User)));
        Assert.That(breakdown.FromClause?.Clause, Does.Contain("User"));
    }

    [Test]
    public void Analyze_WhereClause_ExtractsCondition()
    {
        // Arrange
        var query = from user in TestDataContext.Users
                    where user.Age > 21
                    select user;

        // Act
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Assert
        Assert.That(breakdown.WhereClause?.Clause, Is.Not.Null);
        Assert.That(breakdown.WhereClause?.Clause, Does.Contain("Age"));
        Assert.That(breakdown.WhereClause?.Clause, Does.Contain(">"));
    }

    [Test]
    public void Analyze_SelectWithProjection_ExtractsSelectedFields()
    {
        // Arrange
        var query = from user in TestDataContext.Users
                    select new { user.Id, user.Name };

        // Act
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Assert
        Assert.That(breakdown.SelectClause?.Clause, Is.Not.Null);
        Assert.That(breakdown.SelectClause?.Clause, Does.Contain("Id"));
        Assert.That(breakdown.SelectClause?.Clause, Does.Contain("Name"));
    }

    [Test]
    public void Analyze_OrderByClause_ExtractsOrdering()
    {
        // Arrange
        var query = from user in TestDataContext.Users
                    orderby user.Name
                    select user;

        // Act
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Assert
        Assert.That(breakdown.OrderByClause?.Clause, Is.Not.Null);
        Assert.That(breakdown.OrderByClause?.Clause, Does.Contain("Name"));
    }

    [Test]
    public void Analyze_MethodSyntax_ExtractsCorrectClauses()
    {
        // Arrange
        var query = TestDataContext.Users
            .Where(u => u.Age > 18)
            .OrderBy(u => u.Name)
            .Select(u => new { u.Id, u.Name });

        // Act
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Assert
        Assert.That(breakdown.WhereClause?.Clause, Is.Not.Null);
        Assert.That(breakdown.OrderByClause?.Clause, Is.Not.Null);
        Assert.That(breakdown.SelectClause?.Clause, Is.Not.Null);
    }

    [Test]
    public void Analyze_MethodSyntax_TracksMethodChain()
    {
        // Arrange
        var query = TestDataContext.Users
            .Where(u => u.Age > 18)
            .OrderBy(u => u.Name)
            .Select(u => u.Name);

        // Act
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Assert
        Assert.That(breakdown.MethodCallChain, Is.Not.Empty);
        Assert.That(breakdown.MethodCallChain, Contains.Item("Where"));
        Assert.That(breakdown.MethodCallChain, Contains.Item("OrderBy"));
        Assert.That(breakdown.MethodCallChain, Contains.Item("Select"));
    }

    [Test]
    public void GetQuerySummary_ReturnsFormattedString()
    {
        // Arrange
        var query = TestDataContext.Users.Where(u => u.Age > 21);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
        var summary = breakdown.GetQuerySummary();

        // Assert
        Assert.That(summary, Is.Not.Empty);
        Assert.That(summary, Does.Contain("SELECT"));
        Assert.That(summary, Does.Contain("FROM"));
        Assert.That(summary, Does.Contain("WHERE"));
    }

    [Test]
    public void GetMethodChain_ReturnsMethodSequence()
    {
        // Arrange
        var query = TestDataContext.Users.Where(u => u.Age > 18).OrderBy(u => u.Name);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
        var methodChain = breakdown.GetMethodChain();

        // Assert
        Assert.That(methodChain, Does.Contain("Where"));
        Assert.That(methodChain, Does.Contain("OrderBy"));
        Assert.That(methodChain, Does.Contain("->"));
    }

    [Test]
    public void TryAnalyze_ValidQuery_ReturnsTrue()
    {
        // Arrange
        var query = TestDataContext.Users.Where(u => u.Age > 21);

        // Act
        var success = LinqQueryBreakdown.TryAnalyze(query, out var breakdown, out var error);

        // Assert
        Assert.That(success, Is.True);
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(error, Is.Empty);
    }

    [Test]
    public void TryAnalyze_NullQuery_ReturnsFalse()
    {
        // Arrange
        IQueryable<User>? query = null;

        // Act
        var success = LinqQueryBreakdown.TryAnalyze(query!, out var breakdown, out var error);

        // Assert
        Assert.That(success, Is.False);
        Assert.That(error, Is.Not.Empty);
    }

    [Test]
    public void Analyze_ComplexQuery_HandlesCombinedClauses()
    {
        // Arrange
        var query = from user in TestDataContext.Users
                    where user.Age > 21 && user.IsActive
                    orderby user.Name descending
                    select new { user.Id, user.Name, user.Email };

        // Act
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Assert
        Assert.That(breakdown.SelectClause?.Clause, Does.Contain("Id"));
        Assert.That(breakdown.SelectClause?.Clause, Does.Contain("Name"));
        Assert.That(breakdown.SelectClause?.Clause, Does.Contain("Email"));
        Assert.That(breakdown.WhereClause?.Clause, Does.Contain("Age"));
        Assert.That(breakdown.WhereClause?.Clause, Does.Contain("IsActive"));
        Assert.That(breakdown.OrderByClause?.Clause, Does.Contain("Name"));
    }

    #region Round-Trip and Query Modification Tests

    [Test]
    public void AnalyzeAndModify_AddWhereClause_GeneratesUpdatedSql()
    {
        // Arrange - Analyze an existing LINQ query
        var originalQuery = TestDataContext.Users.Where(u => u.Age > 21);
        var breakdown = LinqQueryBreakdown.Analyze(originalQuery);

        // Act - Add additional filter using breakdown
        breakdown.AddWhereClause("IsActive = 1", "AND");
        var modifiedSql = breakdown.GetSql();

        // Assert
        Assert.That(modifiedSql, Does.Contain("Age"));
        Assert.That(modifiedSql, Does.Contain("IsActive"));
        Assert.That(modifiedSql, Does.Contain("AND"));
    }

    [Test]
    public void AnalyzeAndModify_ChangeSelectClause_GeneratesNewProjection()
    {
        // Arrange - Analyze query with projection
        var originalQuery = TestDataContext.Users.Select(u => new { u.Id, u.Name });
        var breakdown = LinqQueryBreakdown.Analyze(originalQuery);

        // Act - Modify the SELECT clause
        breakdown.SelectClause = new Strata.SqlTools.SqlBreakdown.Classes.SqlExpressionClause
        {
            Clause = "Id, Name, Email, Age"
        };
        var modifiedSql = breakdown.GetSql();

        // Assert
        Assert.That(modifiedSql, Does.Contain("Email"));
        Assert.That(modifiedSql, Does.Contain("Age"));
        Assert.That(modifiedSql, Does.Contain("Id"));
        Assert.That(modifiedSql, Does.Contain("Name"));
    }

    [Test]
    public void AnalyzeAndModify_CloneAndExtend_CreatesIndependentQuery()
    {
        // Arrange - Analyze base query
        var baseQuery = TestDataContext.Users.Where(u => u.Age > 18);
        var baseBreakdown = LinqQueryBreakdown.Analyze(baseQuery);

        // Act - Clone and extend
        var extendedBreakdown = (LinqQueryBreakdown)baseBreakdown.Clone();
        extendedBreakdown.AddWhereClause("IsActive = 1", "AND");
        extendedBreakdown.OrderByClause = new Strata.SqlTools.SqlBreakdown.Classes.SqlExpressionClause(splitOnComma: true)
        {
            Clause = "Name ASC"
        };

        // Assert - Original unchanged
        Assert.That(baseBreakdown.OrderByClause?.Clause, Is.Null.Or.Empty);

        // Extended has new conditions
        var extendedSql = extendedBreakdown.GetSql();
        Assert.That(extendedSql, Does.Contain("IsActive"));
        Assert.That(extendedSql, Does.Contain("ORDER BY"));
    }

    [Test]
    public void AnalyzeAndCompose_MultipleQueries_CreatesUnionScenario()
    {
        // Arrange - Analyze two different queries
        var activeUsersQuery = TestDataContext.Users.Where(u => u.IsActive);
        var activeBreakdown = LinqQueryBreakdown.Analyze(activeUsersQuery);

        var recentUsersQuery = TestDataContext.Users.Where(u => u.Age < 25);
        var recentBreakdown = LinqQueryBreakdown.Analyze(recentUsersQuery);

        // Act - Get SQL for both (could be used in UNION scenario)
        var activeSql = activeBreakdown.GetSql();
        var recentSql = recentBreakdown.GetSql();

        // Assert - Both queries are valid and different
        Assert.That(activeSql, Does.Contain("IsActive"));
        Assert.That(recentSql, Does.Contain("Age"));
        Assert.That(activeSql, Is.Not.EqualTo(recentSql));
    }

    [Test]
    public void AnalyzeAndBuildFilter_IncrementallyAddConditions_BuildsComplexFilter()
    {
        // Arrange - Start with simple query
        var query = TestDataContext.Users;
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - Incrementally add filter conditions (simulating filter builder UI)
        breakdown.AddWhereClause("Age >= 18", "AND");
        breakdown.AddWhereClause("Age <= 65", "AND");
        breakdown.AddWhereClause("IsActive = 1", "AND");

        var filterSql = breakdown.GetSql();

        // Assert
        Assert.That(filterSql, Does.Contain("Age >= 18"));
        Assert.That(filterSql, Does.Contain("Age <= 65"));
        Assert.That(filterSql, Does.Contain("IsActive = 1"));

        // Should have multiple AND conditions
        var andCount = filterSql.Split(separator, StringSplitOptions.None).Length - 1;
        Assert.That(andCount, Is.GreaterThanOrEqualTo(2));
    }

    [Test]
    public void AnalyzeAndPaginate_AddOrderAndLimits_CreatesPaginatedQuery()
    {
        // Arrange - Analyze base query
        var query = TestDataContext.Users.Where(u => u.IsActive);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - Add pagination (ORDER BY required for consistent pagination)
        breakdown.OrderByClause = new Strata.SqlTools.SqlBreakdown.Classes.SqlExpressionClause(splitOnComma: true)
        {
            Clause = "Id ASC"
        };

        // Add pagination metadata as setup clause (simulating OFFSET/FETCH or similar)
        breakdown.SetupClauses.Add("-- Page 1, PageSize 10");

        var paginatedSql = breakdown.GetSql();

        // Assert
        Assert.That(paginatedSql, Does.Contain("ORDER BY"));
        Assert.That(paginatedSql, Does.Contain("Id ASC"));
        Assert.That(breakdown.SetupClauses, Has.Count.EqualTo(1));
    }

    [Test]
    public void AnalyzeAndGenerateReport_ExtractQueryMetrics_ProvidesAnalytics()
    {
        // Arrange - Complex query to analyze
        var query = TestDataContext.Users
            .Where(u => u.Age > 21)
            .Where(u => u.IsActive)
            .OrderBy(u => u.Name)
            .Select(u => new { u.Id, u.Name, u.Email });

        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - Extract metrics
        var methodCount = breakdown.MethodCallChain.Count;
        var hasProjection = breakdown.SelectClause?.Clause != "*";
        var hasFilters = !string.IsNullOrEmpty(breakdown.WhereClause?.Clause);
        var hasOrdering = !string.IsNullOrEmpty(breakdown.OrderByClause?.Clause);
        var summary = breakdown.GetQuerySummary();

        // Assert - Verify analytics
        Assert.That(methodCount, Is.GreaterThan(0));
        Assert.That(hasProjection, Is.True);
        Assert.That(hasFilters, Is.True);
        Assert.That(hasOrdering, Is.True);
        Assert.That(summary, Does.Contain("SELECT"));
        Assert.That(summary, Does.Contain("WHERE"));
        Assert.That(summary, Does.Contain("ORDER BY"));
    }

    [Test]
    public void AnalyzeAndOptimize_RemoveSelectStar_ImprovedProjection()
    {
        // Arrange - Analyze query with SELECT *
        var query = TestDataContext.Users.Where(u => u.IsActive);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Verify it initially has SELECT *
        var originalSql = breakdown.GetSql();
        Assert.That(originalSql, Does.Contain("*").Or.Not.Contain("Id, Name"));

        // Act - Optimize by specifying only needed columns
        breakdown.SelectClause = new Strata.SqlTools.SqlBreakdown.Classes.SqlExpressionClause
        {
            Clause = "Id, Name, Email"
        };

        var optimizedSql = breakdown.GetSql();

        // Assert
        Assert.That(optimizedSql, Does.Contain("Id"));
        Assert.That(optimizedSql, Does.Contain("Name"));
        Assert.That(optimizedSql, Does.Contain("Email"));
        Assert.That(optimizedSql, Does.Not.Contain("SELECT *"));
    }

    [Test]
    public void AnalyzeMultipleQueries_CompareAndMerge_CreatesCompositeQuery()
    {
        // Arrange - Analyze two related queries
        var usersQuery = TestDataContext.Users.Where(u => u.Age > 21);
        var usersBreakdown = LinqQueryBreakdown.Analyze(usersQuery);

        var activeQuery = TestDataContext.Users.Where(u => u.IsActive);
        var activeBreakdown = LinqQueryBreakdown.Analyze(activeQuery);

        // Act - Merge conditions from both queries
        var mergedBreakdown = (LinqQueryBreakdown)usersBreakdown.Clone();

        // Extract WHERE clause from activeBreakdown and add to merged
        if (!string.IsNullOrEmpty(activeBreakdown.WhereClause?.Clause))
        {
            mergedBreakdown.AddWhereClause(activeBreakdown.WhereClause.Clause, "AND");
        }

        var mergedSql = mergedBreakdown.GetSql();

        // Assert - Merged query has both conditions
        Assert.That(mergedSql, Does.Contain("Age"));
        Assert.That(mergedSql, Does.Contain("IsActive"));
    }

    [Test]
    public void AnalyzeAndDocument_GenerateQueryDocumentation_CreatesReadableOutput()
    {
        // Arrange - Analyze a business query
        var query = TestDataContext.Orders
            .Where(o => o.Amount > 1000)
            .Where(o => o.OrderDate > DateTime.Now.AddDays(-30))
            .OrderBy(o => o.OrderDate);

        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - Generate documentation
        var documentation = new System.Text.StringBuilder();
        documentation.AppendLine("Query: High-Value Recent Orders");
        documentation.AppendLine($"Entity: {breakdown.EntityType}");
        documentation.AppendLine($"Method Chain: {breakdown.GetMethodChain()}");
        documentation.AppendLine($"Summary: {breakdown.GetQuerySummary()}");
        documentation.AppendLine();
        documentation.AppendLine("Generated SQL:");
        documentation.AppendLine(breakdown.GetSql());

        var doc = documentation.ToString();

        // Assert - Documentation contains all key information
        Assert.That(doc, Does.Contain("Query:"));
        Assert.That(doc, Does.Contain("Entity:"));
        Assert.That(doc, Does.Contain("Method Chain:"));
        Assert.That(doc, Does.Contain("Summary:"));
        Assert.That(doc, Does.Contain("Generated SQL:"));
        Assert.That(doc, Does.Contain("Amount"));
        Assert.That(doc, Does.Contain("OrderDate"));
    }

    #endregion
}

// Test data context and entities
public class TestDataContext
{
    public static IQueryable<User> Users => new List<User>().AsQueryable();
    public static IQueryable<Order> Orders => new List<Order>().AsQueryable();
}

public class User
{
    public int Id { get; set; }
    public string Name { get; set; } = string.Empty;
    public string Email { get; set; } = string.Empty;
    public int Age { get; set; }
    public bool IsActive { get; set; }
}

public class Order
{
    public int Id { get; set; }
    public int UserId { get; set; }
    public decimal Amount { get; set; }
    public DateTime OrderDate { get; set; }
}

#region GetQuery Tests

public class GetQueryTests
{
    private TestDataContext _context = null!;

    [SetUp]
    public void Setup()
    {
        _context = new TestDataContext();
    }

    [Test]
    public void GetQuery_LinqBreakdown_ReturnsNullByDefault()
    {
        // Arrange
        var query = TestDataContext.Users.Where(u => u.Age > 18);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act - GetQuery returns null because LinqQueryBreakdown needs the original provider
        var result = breakdown.GetQuery<User>();

        // Assert
        Assert.That(result, Is.Null);
    }

    [Test]
    public void GetQuery_SqlServerQueryBreakdown_ReturnsNull()
    {
        // Arrange
        var breakdown = new QueryBreakdown("Id, Name", "Users", "Age > 18");

        // Act
        var result = breakdown.GetQuery<User>();

        // Assert
        Assert.That(result, Is.Null);
    }

    [Test]
    public void GetQuery_MultipleBreakdownTypes_AllReturnNull()
    {
        // Arrange
        var linqBreakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users);
        var sqlBreakdown = new QueryBreakdown("*", "Users");

        // Act
        var linqResult = linqBreakdown.GetQuery<User>();
        var sqlResult = sqlBreakdown.GetQuery<User>();

        // Assert
        Assert.That(linqResult, Is.Null);
        Assert.That(sqlResult, Is.Null);
    }

    #endregion

    #region INSERT Analysis Tests

    [Test]
    public void AnalyzeInsert_SingleEntity_CreatesInsertBreakdown()
    {
        // Arrange
        var entity = new User { Id = 1, Name = "John Doe", Email = "john@example.com", Age = 30 };

        // Act
        var breakdown = LinqQueryBreakdown.AnalyzeInsert(entity);

        // Assert
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(breakdown.TableName.Clause, Is.EqualTo("User"));
        Assert.That(breakdown.InsertIntoClause.Clause, Is.Not.Empty);
        Assert.That(breakdown.ValuesClause.Clause, Is.Not.Empty);
        Assert.That(breakdown.InsertIntoClause.Clause, Does.Contain("Id"));
        Assert.That(breakdown.InsertIntoClause.Clause, Does.Contain("Name"));
    }

    [Test]
    public void AnalyzeInsertRange_MultipleEntities_CreatesInsertBreakdown()
    {
        // Arrange
        var entities = new List<User>
        {
            new User { Id = 1, Name = "John Doe", Email = "john@example.com", Age = 30 },
            new User { Id = 2, Name = "Jane Smith", Email = "jane@example.com", Age = 28 }
        };

        // Act
        var breakdown = LinqQueryBreakdown.AnalyzeInsertRange(entities);

        // Assert
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(breakdown.TableName.Clause, Is.EqualTo("User"));
        Assert.That(breakdown.InsertIntoClause.Clause, Is.Not.Empty);
        Assert.That(breakdown.ValuesClause.Clause, Does.Contain("("));
    }

    [Test]
    public void AnalyzeInsert_NullEntity_ThrowsArgumentNullException()
    {
        // Act & Assert
        Assert.Throws<ArgumentNullException>(() => LinqQueryBreakdown.AnalyzeInsert<User>(null!));
    }

    #endregion

    #region DELETE Analysis Tests

    [Test]
    public void AnalyzeDelete_WithFilterExpression_CreatesDeleteBreakdown()
    {
        // Arrange
        var filterExpression = System.Linq.Expressions.Expression.Lambda<System.Func<User, bool>>(
            System.Linq.Expressions.Expression.Constant(true),
            System.Linq.Expressions.Expression.Parameter(typeof(User), "u")
        );

        // Act
        var breakdown = LinqQueryBreakdown.AnalyzeDelete(filterExpression);

        // Assert
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(breakdown.FromClause.Clause, Is.EqualTo("User"));
    }

    [Test]
    public void AnalyzeDelete_NullFilter_ThrowsArgumentNullException()
    {
        // Act & Assert
        Assert.Throws<ArgumentNullException>(() =>
            LinqQueryBreakdown.AnalyzeDelete<User>(null!));
    }

    #endregion

    #region UPDATE Analysis Tests

    [Test]
    public void AnalyzeUpdate_WithFilterAndUpdateExpressions_CreatesUpdateBreakdown()
    {
        // Arrange
        var filterExpr = System.Linq.Expressions.Expression.Lambda<System.Func<User, bool>>(
            System.Linq.Expressions.Expression.Constant(true),
            System.Linq.Expressions.Expression.Parameter(typeof(User), "u")
        );

        var updateExpr = System.Linq.Expressions.Expression.Lambda<System.Func<User, User>>(
            System.Linq.Expressions.Expression.Constant(new User()),
            System.Linq.Expressions.Expression.Parameter(typeof(User), "u")
        );

        // Act
        var breakdown = LinqQueryBreakdown.AnalyzeUpdate(filterExpr, updateExpr);

        // Assert
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(breakdown.TableName.Clause, Is.EqualTo("User"));
    }

    [Test]
    public void AnalyzeUpdate_NullFilter_ThrowsArgumentNullException()
    {
        // Arrange
        var updateExpr = System.Linq.Expressions.Expression.Lambda<System.Func<User, User>>(
            System.Linq.Expressions.Expression.Constant(new User()),
            System.Linq.Expressions.Expression.Parameter(typeof(User), "u")
        );

        // Act & Assert
        Assert.Throws<ArgumentNullException>(() =>
            LinqQueryBreakdown.AnalyzeUpdate<User>(null!, updateExpr));
    }

    [Test]
    public void AnalyzeUpdate_NullUpdateExpression_ThrowsArgumentNullException()
    {
        // Arrange
        var filterExpr = System.Linq.Expressions.Expression.Lambda<System.Func<User, bool>>(
            System.Linq.Expressions.Expression.Constant(true),
            System.Linq.Expressions.Expression.Parameter(typeof(User), "u")
        );

        // Act & Assert
        Assert.Throws<ArgumentNullException>(() =>
            LinqQueryBreakdown.AnalyzeUpdate<User>(filterExpr, null!));
    }

    #endregion

    #region PROCEDURE Analysis Tests

    [Test]
    public void AnalyzeProcedure_WithName_CreatesProcedureBreakdown()
    {
        // Arrange
        const string procName = "sp_GetUsers";

        // Act
        var breakdown = LinqQueryBreakdown.AnalyzeProcedure(procName);

        // Assert
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(breakdown.ProcedureName.Clause, Is.EqualTo(procName));
    }

    [Test]
    public void AnalyzeProcedure_WithParameters_CreatesProcedureBreakdownWithParams()
    {
        // Arrange
        const string procName = "sp_GetUsersByAge";
        var parameters = new object[] { 18, 65 };

        // Act
        var breakdown = LinqQueryBreakdown.AnalyzeProcedure(procName, parameters);

        // Assert
        Assert.That(breakdown, Is.Not.Null);
        Assert.That(breakdown.ProcedureName.Clause, Is.EqualTo(procName));
        Assert.That(breakdown.Parameters, Is.Not.Empty);
        Assert.That(breakdown.Parameters, Has.Count.EqualTo(2));
    }

    [Test]
    public void AnalyzeProcedure_NullOrEmptyName_ThrowsArgumentException()
    {
        // Act & Assert
        Assert.Throws<ArgumentException>(() => LinqQueryBreakdown.AnalyzeProcedure(null!));
        Assert.Throws<ArgumentException>(() => LinqQueryBreakdown.AnalyzeProcedure(""));
    }

    #endregion

    #region TRACE Analysis Tests

    [Test]
    public void AnalyzeTrace_WithValidQuery_ReturnsTraceString()
    {
        // Arrange
        var query = TestDataContext.Users.Where(u => u.Age > 18);

        // Act
        var trace = LinqQueryBreakdown.AnalyzeTrace(query);

        // Assert
        Assert.That(trace, Is.Not.Null.And.Not.Empty);
        Assert.That(trace, Does.Contain("User"));
        Assert.That(trace, Does.Contain("Query Provider"));
        Assert.That(trace, Does.Contain("Timestamp"));
    }

    [Test]
    public void AnalyzeTrace_WithExecutionContext_IncludesContextInTrace()
    {
        // Arrange
        var query = TestDataContext.Users;
        const string context = "Initial Load";

        // Act
        var trace = LinqQueryBreakdown.AnalyzeTrace(query, context);

        // Assert
        Assert.That(trace, Is.Not.Null);
        Assert.That(trace, Does.Contain(context));
        Assert.That(trace, Does.Contain("Execution Context"));
    }

    [Test]
    public void AnalyzeTrace_NullQuery_ThrowsArgumentNullException()
    {
        // Act & Assert
        Assert.Throws<ArgumentNullException>(() =>
            LinqQueryBreakdown.AnalyzeTrace<User>(null!));
    }

    #endregion

    #region Conversion Tests

    [Test]
    public void ConvertToSqlServerBreakdown_CopiesAllClauses()
    {
        // Arrange
        var query = TestDataContext.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
        var sqlServerBreakdown = breakdown.ConvertToSqlServerBreakdown();

        // Assert
        Assert.That(sqlServerBreakdown, Is.Not.Null);
        Assert.That(sqlServerBreakdown.SelectClause?.Clause, Is.EqualTo(breakdown.SelectClause?.Clause));
        Assert.That(sqlServerBreakdown.FromClause?.Clause, Is.EqualTo(breakdown.FromClause?.Clause));
        Assert.That(sqlServerBreakdown.WhereClause?.Clause, Is.EqualTo(breakdown.WhereClause?.Clause));
        Assert.That(sqlServerBreakdown.OrderByClause?.Clause, Is.EqualTo(breakdown.OrderByClause?.Clause));
    }

    [Test]
    public void ConvertToPostgreSqlBreakdown_CopiesAllClauses()
    {
        // Arrange
        var query = TestDataContext.Users
            .Where(u => u.IsActive)
            .OrderBy(u => u.Name)
            .Select(u => new { u.Id, u.Name });
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
        var postgresBreakdown = breakdown.ConvertToPostgreSqlBreakdown();

        // Assert
        Assert.That(postgresBreakdown, Is.Not.Null);
        Assert.That(postgresBreakdown.SelectClause?.Clause, Is.EqualTo(breakdown.SelectClause?.Clause));
        Assert.That(postgresBreakdown.FromClause?.Clause, Is.EqualTo(breakdown.FromClause?.Clause));
        Assert.That(postgresBreakdown.WhereClause?.Clause, Is.EqualTo(breakdown.WhereClause?.Clause));
        Assert.That(postgresBreakdown.OrderByClause?.Clause, Is.EqualTo(breakdown.OrderByClause?.Clause));
    }

    [Test]
    public void ConvertToSnowflakeBreakdown_CopiesAllClauses()
    {
        // Arrange
        var query = TestDataContext.Users.Where(u => u.Age > 21).OrderBy(u => u.Name);
        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
        var snowflakeBreakdown = breakdown.ConvertToSnowflakeBreakdown();

        // Assert
        Assert.That(snowflakeBreakdown, Is.Not.Null);
        Assert.That(snowflakeBreakdown.SelectClause?.Clause, Is.EqualTo(breakdown.SelectClause?.Clause));
        Assert.That(snowflakeBreakdown.FromClause?.Clause, Is.EqualTo(breakdown.FromClause?.Clause));
        Assert.That(snowflakeBreakdown.WhereClause?.Clause, Is.EqualTo(breakdown.WhereClause?.Clause));
        Assert.That(snowflakeBreakdown.OrderByClause?.Clause, Is.EqualTo(breakdown.OrderByClause?.Clause));
    }

    [Test]
    public void ConvertToSqlServerBreakdown_WithComments_PreservesComments()
    {
        // Arrange
        var breakdown = new LinqQueryBreakdown("Id, Name", "Users", "Age > 21");
        breakdown.SelectClause.Comment = "Select user columns";
        breakdown.WhereClause.Comment = "Filter adult users";

        // Act
        var sqlServerBreakdown = breakdown.ConvertToSqlServerBreakdown();

        // Assert
        Assert.That(sqlServerBreakdown.SelectClause?.Comment, Is.EqualTo("Select user columns"));
        Assert.That(sqlServerBreakdown.WhereClause?.Comment, Is.EqualTo("Filter adult users"));
    }

    [Test]
    public void ConvertToPostgreSqlBreakdown_WithComplexQuery_CopieAllClauses()
    {
        // Arrange
        var query = TestDataContext.Users
            .Where(u => u.IsActive && u.Age >= 18)
            .OrderByDescending(u => u.Age);

        var breakdown = LinqQueryBreakdown.Analyze(query);

        // Act
        var postgresBreakdown = breakdown.ConvertToPostgreSqlBreakdown();

        // Assert
        Assert.That(postgresBreakdown.SelectClause?.Clause, Is.Not.Null);
        Assert.That(postgresBreakdown.FromClause?.Clause, Is.Not.Null);
        Assert.That(postgresBreakdown.WhereClause?.Clause, Is.Not.Null);
        Assert.That(postgresBreakdown.GroupByClause?.Clause, Is.Not.Null);
        Assert.That(postgresBreakdown.OrderByClause?.Clause, Is.Not.Null);
    }

    [Test]
    public void ConvertToSnowflakeBreakdown_PreservesAllClauseInformation()
    {
        // Arrange
        var breakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users.OrderBy(u => u.Name));

        // Act
        var snowflakeBreakdown = breakdown.ConvertToSnowflakeBreakdown();

        // Assert
        Assert.That(snowflakeBreakdown.FromClause?.Clause, Is.EqualTo(breakdown.FromClause?.Clause));
        Assert.That(snowflakeBreakdown.OrderByClause?.Clause, Is.EqualTo(breakdown.OrderByClause?.Clause));
    }

    [Test]
    public void ConvertToSqlServerBreakdown_InstancesAreIndependent()
    {
        // Arrange
        var breakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users.Where(u => u.Age > 21));
        var sqlServerBreakdown = breakdown.ConvertToSqlServerBreakdown();

        // Act - Modify the SQL Server breakdown
        sqlServerBreakdown.SelectClause.Clause = "Id, Name, Email";

        // Assert - Original should be unchanged
        Assert.That(breakdown.SelectClause?.Clause, Is.Not.EqualTo(sqlServerBreakdown.SelectClause?.Clause));
    }

    [Test]
    public void ConvertChainMultipleTimes_EachConversionIndependent()
    {
        // Arrange
        var breakdown = LinqQueryBreakdown.Analyze(TestDataContext.Users.OrderBy(u => u.Name));

        // Act
        var sqlServer1 = breakdown.ConvertToSqlServerBreakdown();
        var sqlServer2 = breakdown.ConvertToSqlServerBreakdown();

        // Assert - Both should have same data but be different instances
        Assert.That(sqlServer1, Is.Not.SameAs(sqlServer2));
        Assert.That(sqlServer1.OrderByClause?.Clause, Is.EqualTo(sqlServer2.OrderByClause?.Clause));
    }

    #endregion
}