using System.Reflection;

namespace StellaOps.BinaryIndex.GroundTruth.Buildinfo.Tests.Fixtures;

/// <summary>
/// Provides access to deterministic test fixtures for offline testing.
/// </summary>
public static class FixtureProvider
{
    private static readonly string FixturesPath;

    static FixtureProvider()
    {
        var assemblyDir = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location)!;
        FixturesPath = Path.Combine(assemblyDir, "Fixtures");

        // Also try the source directory for development
        if (!Directory.Exists(FixturesPath))
        {
            var sourceDir = FindSourceFixturesDirectory();
            if (sourceDir is not null)
            {
                FixturesPath = sourceDir;
            }
        }
    }

    /// <summary>
    /// Get sample .buildinfo file content for curl package.
    /// </summary>
    public static string GetSampleBuildinfoCurl()
    {
        var path = Path.Combine(FixturesPath, "curl_7.88.1-10_amd64.buildinfo");
        if (!File.Exists(path))
        {
            // Return inline fixture if file doesn't exist
            return SampleBuildinfoContent;
        }
        return File.ReadAllText(path);
    }

    /// <summary>
    /// Get sample signed .buildinfo file content.
    /// </summary>
    public static string GetSampleSignedBuildinfo()
    {
        var path = Path.Combine(FixturesPath, "openssl_3.0.11-1_amd64.buildinfo.asc");
        if (!File.Exists(path))
        {
            return SampleSignedBuildinfoContent;
        }
        return File.ReadAllText(path);
    }

    /// <summary>
    /// Get a fixture file as a stream.
    /// </summary>
    public static Stream GetFixtureStream(string name)
    {
        var path = Path.Combine(FixturesPath, name);
        if (!File.Exists(path))
        {
            throw new FileNotFoundException($"Fixture not found: {path}");
        }
        return File.OpenRead(path);
    }

    /// <summary>
    /// Check if a fixture exists.
    /// </summary>
    public static bool FixtureExists(string name)
    {
        var path = Path.Combine(FixturesPath, name);
        return File.Exists(path);
    }

    private static string? FindSourceFixturesDirectory()
    {
        var dir = Directory.GetCurrentDirectory();
        while (dir is not null)
        {
            var candidate = Path.Combine(dir, "src", "BinaryIndex", "__Tests",
                "StellaOps.BinaryIndex.GroundTruth.Buildinfo.Tests", "Fixtures");
            if (Directory.Exists(candidate))
            {
                return candidate;
            }
            dir = Directory.GetParent(dir)?.FullName;
        }
        return null;
    }

    /// <summary>
    /// Inline sample buildinfo content for deterministic testing.
    /// </summary>
    private const string SampleBuildinfoContent = """
        Format: 1.0
        Source: curl
        Binary: curl libcurl4 libcurl4-openssl-dev
        Architecture: amd64 source
        Version: 7.88.1-10
        Checksums-Sha256:
         abc123def456789012345678901234567890123456789012345678901234 12345 curl_7.88.1-10_amd64.deb
         def456abc789012345678901234567890123456789012345678901234567 23456 libcurl4_7.88.1-10_amd64.deb
        Build-Origin: debian
        Build-Architecture: amd64
        Build-Date: Mon, 15 Jan 2024 10:30:00 +0000
        Build-Path: /build/curl-xyz123
        Installed-Build-Depends:
         gcc (= 12.2.0-14),
         libc6 (= 2.36-9),
         libssl-dev (= 3.0.11-1),
         zlib1g-dev (= 1:1.2.13.dfsg-1)
        Environment:
         DEB_BUILD_OPTIONS="parallel=8"
         LANG="C.UTF-8"
         SOURCE_DATE_EPOCH="1705315800"
        """;

    /// <summary>
    /// Inline sample signed buildinfo content.
    /// </summary>
    private const string SampleSignedBuildinfoContent = """
        -----BEGIN PGP SIGNED MESSAGE-----
        Hash: SHA512

        Format: 1.0
        Source: openssl
        Binary: openssl libssl3 libssl-dev
        Architecture: amd64 source
        Version: 3.0.11-1
        Checksums-Sha256:
         fedcba9876543210fedcba9876543210fedcba9876543210fedcba98765 45678 openssl_3.0.11-1_amd64.deb
         012345abcdef6789012345abcdef6789012345abcdef6789012345abcdef 56789 libssl3_3.0.11-1_amd64.deb
        Build-Origin: debian
        Build-Architecture: amd64
        Build-Date: Tue, 16 Jan 2024 14:00:00 +0000
        Build-Path: /build/openssl-abc456
        Installed-Build-Depends:
         gcc (= 12.2.0-14),
         libc6 (= 2.36-9),
         perl (= 5.36.0-7)
        Environment:
         DEB_BUILD_OPTIONS="nocheck"
         LANG="C.UTF-8"
        -----BEGIN PGP SIGNATURE-----

        iQIzBAEBCgAdFiEE1234567890abcdef1234567890abcdef12345FiQI
        ZABC123/ABC123ABC123ABC123ABC123ABC123ABC123ABC123ABC123ABC1
        23ABC123ABC123ABC123ABC123ABC123ABC123ABC123ABC123ABC123ABC1
        =wxYz
        -----END PGP SIGNATURE-----
        """;
}

/// <summary>
/// Test fixture constants for buildinfo tests.
/// </summary>
public static class FixtureConstants
{
    // Sample package info
    public const string SampleSourcePackageCurl = "curl";
    public const string SampleVersionCurl = "7.88.1-10";
    public const string SampleArchitectureAmd64 = "amd64";

    public const string SampleSourcePackageOpenssl = "openssl";
    public const string SampleVersionOpenssl = "3.0.11-1";

    // Expected binary names
    public const string ExpectedBinaryCurl = "curl";
    public const string ExpectedBinaryLibcurl = "libcurl4";
    public const string ExpectedBinaryOpenssl = "openssl";
    public const string ExpectedBinaryLibssl = "libssl3";
}