// -----------------------------------------------------------------------------
// ReachabilityTestFixture.cs
// Sprint: SPRINT_3500_0004_0003_integration_tests_corpus
// Task: T2 - Reachability Integration Tests
// Description: Test fixture for reachability integration tests
// -----------------------------------------------------------------------------

using System.Reflection;

namespace StellaOps.Integration.Reachability;

/// <summary>
/// Test fixture for reachability integration tests.
/// Provides access to corpus fixtures and test data.
/// </summary>
public sealed class ReachabilityTestFixture
{
    private readonly string _corpusBasePath;
    private readonly string _fixturesBasePath;

    public ReachabilityTestFixture()
    {
        var assemblyLocation = Assembly.GetExecutingAssembly().Location;
        var assemblyDirectory = Path.GetDirectoryName(assemblyLocation)!;
        
        _corpusBasePath = Path.Combine(assemblyDirectory, "corpus");
        _fixturesBasePath = Path.Combine(assemblyDirectory, "fixtures");
    }

    /// <summary>
    /// Gets the path to a language-specific corpus directory.
    /// </summary>
    /// <param name="language">Language identifier (dotnet, java, python, etc.)</param>
    /// <returns>Full path to the corpus directory</returns>
    public string GetCorpusPath(string language)
    {
        var corpusPath = Path.Combine(_corpusBasePath, language);
        
        if (!Directory.Exists(corpusPath))
        {
            throw new DirectoryNotFoundException(
                $"Corpus directory not found for language '{language}' at: {corpusPath}");
        }
        
        return corpusPath;
    }

    /// <summary>
    /// Gets the path to a specific fixture directory.
    /// </summary>
    /// <param name="fixtureName">Name of the fixture</param>
    /// <returns>Full path to the fixture directory</returns>
    public string GetFixturePath(string fixtureName)
    {
        var fixturePath = Path.Combine(_fixturesBasePath, fixtureName);
        
        if (!Directory.Exists(fixturePath))
        {
            throw new DirectoryNotFoundException(
                $"Fixture directory not found: {fixturePath}");
        }
        
        return fixturePath;
    }

    /// <summary>
    /// Lists all available corpus languages.
    /// </summary>
    public IReadOnlyList<string> GetAvailableCorpusLanguages()
    {
        if (!Directory.Exists(_corpusBasePath))
        {
            return Array.Empty<string>();
        }

        return Directory.GetDirectories(_corpusBasePath)
            .Select(Path.GetFileName)
            .Where(name => !string.IsNullOrEmpty(name))
            .Cast<string>()
            .ToList();
    }

    /// <summary>
    /// Checks if a corpus exists for the given language.
    /// </summary>
    public bool HasCorpus(string language)
    {
        var corpusPath = Path.Combine(_corpusBasePath, language);
        return Directory.Exists(corpusPath);
    }
}