sql-utilities/tests/Strata.SqlTools.Markdown.Tests/SqlServer/QueryBreakdownGeneratorTests.cs

using Strata.SqlTools.Breakdowns.SqlServer;
using Strata.SqlTools.Markdown.SqlServer;
using Interfaces = Strata.SqlTools.SqlBreakdown.Interfaces;

namespace Strata.SqlTools.Markdown.Tests.SqlServer;

[TestFixture]
public class QueryBreakdownGeneratorTests
{
    private QueryBreakdownGenerator _generator = null!;

    [SetUp]
    public void Setup()
    {
        _generator = new QueryBreakdownGenerator();
    }

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

        // Act
        var result = QueryBreakdownGenerator.GenerateMermaidDiagram(query);

        // Assert
        Assert.That(result, Does.Contain("```mermaid"));
        Assert.That(result, Does.Contain("flowchart TD"));
        Assert.That(result, Does.Contain("SELECT"));
        Assert.That(result, Does.Contain("FROM"));
        Assert.That(result, Does.Contain("```"));
    }

    [Test]
    public void GenerateMermaidDiagram_WithComplexQuery_IncludesAllClauses()
    {
        // Arrange
        var query = new QueryBreakdown(
            "u.ID, u.Name, COUNT(o.OrderID) as OrderCount",
            "Users u JOIN Orders o ON u.ID = o.UserID",
            "u.Active = 1"
        );
        query.GroupByClause.Clause = "u.ID, u.Name";
        query.HavingClause.Clause = "COUNT(o.OrderID) > 5";
        query.OrderByClause.Clause = "OrderCount DESC";

        // Act
        var result = QueryBreakdownGenerator.GenerateMermaidDiagram(query, "User Orders Query");

        // Assert
        Assert.That(result, Does.Contain("### User Orders Query"));
        Assert.That(result, Does.Contain("SELECT"));
        Assert.That(result, Does.Contain("FROM"));
        Assert.That(result, Does.Contain("WHERE"));
        Assert.That(result, Does.Contain("GROUP BY"));
        Assert.That(result, Does.Contain("HAVING"));
        Assert.That(result, Does.Contain("ORDER BY"));
    }

    [Test]
    public void GenerateMermaidDiagram_WithWhereClause_UsesDecisionShape()
    {
        // Arrange
        var query = new QueryBreakdown("*", "Products", "Price > 100");

        // Act
        var result = QueryBreakdownGenerator.GenerateMermaidDiagram(query);

        // Assert
        Assert.That(result, Does.Contain("WHERE"));
        Assert.That(result, Does.Contain("{"));
        Assert.That(result, Does.Contain("}"));
    }

    [Test]
    public void GenerateMermaidDiagram_ParsedQuery_GeneratesDiagram()
    {
        // Arrange
        var sql = @"
            SELECT u.ID, u.Name, u.Email
            FROM Users u
            WHERE u.Active = 1
            ORDER BY u.Name";

        var query = QueryBreakdown.Parse(sql);

        // Act
        var result = QueryBreakdownGenerator.GenerateMermaidDiagram(query);

        // Assert
        Assert.That(result, Is.Not.Null);
        Assert.That(result, Does.Contain("mermaid"));
        Assert.That(result, Does.Contain("SELECT"));
        Assert.That(result.Length, Is.GreaterThan(100));
    }

    [Test]
    public void GenerateMermaidDiagram_WithTitle_IncludesTitle()
    {
        // Arrange
        var query = new QueryBreakdown("*", "Users");

        // Act
        var result = QueryBreakdownGenerator.GenerateMermaidDiagram(query, "Test Query");

        // Assert
        Assert.That(result, Does.StartWith("### Test Query"));
    }

    [Test]
    public void GenerateMermaidDiagram_WithoutTitle_NoTitle()
    {
        // Arrange
        var query = new QueryBreakdown("*", "Users");

        // Act
        var result = QueryBreakdownGenerator.GenerateMermaidDiagram(query);

        // Assert
        Assert.That(result, Does.Not.StartWith("###"));
        Assert.That(result, Does.StartWith("```mermaid"));
    }

    [Test]
    public void GenerateMermaidDiagram_WithLongClause_TruncatesText()
    {
        // Arrange
        var longSelect = string.Join(", ", Enumerable.Range(1, 50).Select(i => $"Column{i}"));
        var query = new QueryBreakdown(longSelect, "LargeTable");

        // Act
        var result = QueryBreakdownGenerator.GenerateMermaidDiagram(query);

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

    [Test]
    public void GenerateMermaidDiagram_ISqlBreakdown_GeneratesSimpleDiagram()
    {
        // Arrange
        var query = new QueryBreakdown("*", "Users");
        query.SetupClauses.Add("CREATE TEMP TABLE #Temp (ID INT)");

        // Act
        var result = _generator.GenerateMermaidDiagram((Interfaces.ISqlBreakdown)query);

        // Assert
        Assert.That(result, Does.Contain("mermaid"));
        Assert.That(result, Does.Contain("flowchart TD"));
        Assert.That(result, Does.Contain("Users"));
    }
}