using Strata.SqlTools.Breakdowns.Snowflake;

namespace Strata.SqlTools.Snowflake.Tests.Snowflake;

[TestFixture]
public class QueryBreakdownCollectionTests
{
    private QueryBreakdownCollection _collection = null!;

    [SetUp]
    public void Setup()
    {
        _collection = new QueryBreakdownCollection();
    }

    [Test]
    public void Constructor_Empty_CreatesEmptyCollection()
    {
        // Act & Assert
        Assert.That(_collection, Is.Empty);
        Assert.That(_collection.QueryBreakdowns, Is.Empty);
    }

    [Test]
    public void Constructor_WithQueries_InitializesCollection()
    {
        // Arrange
        var queries = new List<QueryBreakdown>
        {
            new QueryBreakdown("ID, Name", "Users"),
            new QueryBreakdown("OrderID, Amount", "Orders")
        };

        // Act
        var collection = new QueryBreakdownCollection(queries);

        // Assert
        Assert.That(collection, Has.Count.EqualTo(2));
        Assert.That(collection.QueryBreakdowns, Has.Count.EqualTo(2));
    }

    [Test]
    public void Add_SingleQuery_AddsToCollection()
    {
        // Arrange
        var query = new QueryBreakdown("ID, Name", "Users");

        // Act
        _collection.Add(query);

        // Assert
        Assert.That(_collection, Has.Count.EqualTo(1));
        Assert.That(_collection.QueryBreakdowns[0], Is.EqualTo(query));
    }

    [Test]
    public void Add_NullQuery_ThrowsArgumentNullException()
    {
        // Act & Assert
        Assert.Throws<ArgumentNullException>(() => _collection.Add(null!));
    }

    [Test]
    public void GetSnowflakeBatch_MultipleQueries_SeparatedBySemicolons()
    {
        // Arrange
        _collection.Add(new QueryBreakdown("ID, Name", "Users"));
        _collection.Add(new QueryBreakdown("OrderID, Amount", "Orders"));

        // Act
        var sql = _collection.GetSnowflakeBatch();

        // Assert
        Assert.That(sql, Does.Contain(";"));
        Assert.That(sql, Does.Contain("SELECT"));
    }

    [Test]
    public void GetSnowflakeBatch_WithSessionSetup_IncludesAlterSession()
    {
        // Arrange
        _collection.Add(new QueryBreakdown("ID, Name", "Users"));

        // Act
        var sql = _collection.GetSnowflakeBatch(includeSessionSetup: true);

        // Assert
        Assert.That(sql, Does.Contain("ALTER SESSION"));
        Assert.That(sql, Does.Contain("Session Setup"));
    }

    [Test]
    public void WhereUseStageReference_WithStageReference_ReturnsMatching()
    {
        // Arrange
        var queryWithStage = new QueryBreakdown("$1, $2", "@mystage/data.csv");
        var queryWithoutStage = new QueryBreakdown("ID, Name", "Users");

        _collection.Add(queryWithStage);
        _collection.Add(queryWithoutStage);

        // Act
        var results = _collection.WhereUseStageReference().ToList();

        // Assert
        Assert.That(results, Has.Count.EqualTo(1));
    }

    [Test]
    public void WhereUseStageReference_WithParameterSyntax_ExcludesParameters()
    {
        // Arrange
        var queryWithParameter = new QueryBreakdown("ID, Name", "Users", "ID = @UserId");
        var queryWithStage = new QueryBreakdown("$1, $2", "@mystage/data.csv");

        _collection.Add(queryWithParameter);
        _collection.Add(queryWithStage);

        // Act
        var results = _collection.WhereUseStageReference().ToList();

        // Assert
        // Only the stage reference query should be returned, not the parameter query
        Assert.That(results, Has.Count.EqualTo(1));
        Assert.That(results[0], Is.EqualTo(queryWithStage));
    }

    [Test]
    public void WhereUseSemiStructuredData_WithJsonFunctions_ReturnsMatching()
    {
        // Arrange
        var queryWithJson = new QueryBreakdown("JSON_EXTRACT(data, '$.id')", "raw_data");
        var queryWithoutJson = new QueryBreakdown("ID, Name", "Users");

        _collection.Add(queryWithJson);
        _collection.Add(queryWithoutJson);

        // Act
        var results = _collection.WhereUseSemiStructuredData().ToList();

        // Assert
        Assert.That(results, Has.Count.EqualTo(1));
    }

    [Test]
    public void GetTotalSelectedColumns_MultipleQueries_SumsColumns()
    {
        // Arrange
        _collection.Add(new QueryBreakdown("ID, Name, Email", "Users"));
        _collection.Add(new QueryBreakdown("OrderID, Amount", "Orders"));

        // Act
        var columnCount = _collection.GetTotalSelectedColumns();

        // Assert
        Assert.That(columnCount, Is.EqualTo(5));
    }

    [Test]
    public void GetUniqueTableReferences_MultipleQueries_ReturnsUniqueTables()
    {
        // Arrange
        _collection.Add(new QueryBreakdown("ID, Name", "Users"));
        _collection.Add(new QueryBreakdown("OrderID, UserID", "Orders"));
        _collection.Add(new QueryBreakdown("ID", "Users"));

        // Act
        var tables = _collection.GetUniqueTableReferences().ToList();

        // Assert
        Assert.That(tables, Has.Count.EqualTo(2));
        Assert.That(tables, Does.Contain("Users"));
        Assert.That(tables, Does.Contain("Orders"));
    }

    [Test]
    public void GetQuerySummaries_WithQueries_ReturnsSummaryWithSnowflakeFeatures()
    {
        // Arrange
        var jsonQuery = new QueryBreakdown("JSON_EXTRACT(data, '$.id')", "raw_data");
        var stageQuery = new QueryBreakdown("$1, $2", "@mystage/data.csv");

        _collection.Add(jsonQuery);
        _collection.Add(stageQuery);

        // Act
        var summaries = _collection.GetQuerySummaries().ToList();

        // Assert
        Assert.That(summaries, Has.Count.EqualTo(2));
        Assert.Multiple(() =>
        {
            Assert.That(summaries[0].UsesSemiStructuredData, Is.True);
            Assert.That(summaries[1].UsesStageReference, Is.True);
        });
    }

    [Test]
    public void SynchronizeParameters_ParametersInSomeQueries_SynchronizesAcrossQueries()
    {
        // Arrange
        var query1 = new QueryBreakdown("ID, Name", "Users", "ID = :UserId");
        var query2 = new QueryBreakdown("OrderID", "Orders", "UserID = :UserId");
        query1.Parameters["UserId"] = 123;
        query2.Parameters["UserId"] = 456;
        _collection.Add(query1);
        _collection.Add(query2);

        // Act
        _collection.SynchronizeParameters();

        // Assert
        Assert.That(query1.Parameters["UserId"], Is.EqualTo(query2.Parameters["UserId"]));
    }

    [Test]
    public void AddParameterToAll_AddsParameterToAllQueries()
    {
        // Arrange
        _collection.Add(new QueryBreakdown("ID, Name", "Users"));
        _collection.Add(new QueryBreakdown("OrderID", "Orders"));

        // Act
        _collection.AddParameterToAll("CompanyId", 99);

        Assert.Multiple(() =>
        {
            // Assert
            Assert.That(_collection.QueryBreakdowns[0].Parameters["CompanyId"], Is.EqualTo(99));
            Assert.That(_collection.QueryBreakdowns[1].Parameters["CompanyId"], Is.EqualTo(99));
        });
    }

    [Test]
    public void GetParameterUsageReport_WithParameters_ReturnsUsageReport()
    {
        // Arrange
        var query1 = new QueryBreakdown("ID, Name", "Users", "ID = :UserId");
        var query2 = new QueryBreakdown("OrderID", "Orders", "UserID = :UserId AND Status = :Status");
        query1.Parameters["UserId"] = 123;
        query2.Parameters["UserId"] = 123;
        query2.Parameters["Status"] = "Active";
        _collection.Add(query1);
        _collection.Add(query2);

        // Act
        var report = _collection.GetParameterUsageReport().ToList();

        // Assert
        Assert.That(report, Is.Not.Empty);
        var userIdReport = report.FirstOrDefault(r => r.ParameterName == "UserId");
        Assert.That(userIdReport, Is.Not.Null);
        Assert.That(userIdReport?.UsedInQueryCount, Is.EqualTo(2));
    }

    [Test]
    public void GetParametersAsString_WithParameters_FormatsSnowflakeStyle()
    {
        // Arrange
        _collection.Add(new QueryBreakdown("ID, Name", "Users", "ID = :UserId"));
        _collection.QueryBreakdowns[0].Parameters["UserId"] = 123;

        // Act
        var paramString = _collection.GetParametersAsString(includeDataTypes: true);

        // Assert
        Assert.That(paramString, Does.Contain(":UserId"));
        Assert.That(paramString, Does.Contain("NUMBER"));
    }

    [Test]
    public void Clear_WithQueries_RemovesAllQueries()
    {
        // Arrange
        _collection.Add(new QueryBreakdown("ID, Name", "Users"));
        _collection.Add(new QueryBreakdown("OrderID", "Orders"));

        // Act
        _collection.Clear();

        // Assert
        Assert.That(_collection, Is.Empty);
    }
}