using Google.Protobuf;
using MxGateway.Client;
using MxGateway.Contracts.Proto;

namespace MxGateway.Client.Tests;

public sealed class MxCommandReplyExtensionsTests
{
    /// <summary>Verifies that successful replies pass both protocol and MxAccess success checks.</summary>
    [Fact]
    public void EnsureSuccess_WithRegisterFixture_ReturnsReply()
    {
        MxCommandReply reply = ReadReplyFixture("register.ok.reply.json");

        Assert.Same(reply, reply.EnsureProtocolSuccess());
        Assert.Same(reply, reply.EnsureMxAccessSuccess());
    }

    /// <summary>Verifies that MxAccess failures throw with preserved HResult and status details.</summary>
    [Fact]
    public void EnsureMxAccessSuccess_WithFailureFixture_PreservesHResultAndStatuses()
    {
        MxCommandReply reply = ReadReplyFixture("write.mxaccess-failure.reply.json");

        reply.EnsureProtocolSuccess();
        MxAccessException exception = Assert.Throws<MxAccessException>(
            reply.EnsureMxAccessSuccess);

        Assert.Equal(-2147220992, exception.HResultCode);
        Assert.Equal(reply.Statuses.Count, exception.Statuses.Count);
        Assert.Equal(reply, exception.Reply);
        Assert.Contains("0x80040200", exception.Message);
    }

    /// <summary>Verifies that session-not-found protocol failures throw the correct gateway exception.</summary>
    [Fact]
    public void EnsureProtocolSuccess_WithSessionFailure_ThrowsSessionException()
    {
        MxCommandReply reply = new()
        {
            SessionId = "session-missing",
            CorrelationId = "correlation",
            ProtocolStatus = new ProtocolStatus
            {
                Code = ProtocolStatusCode.SessionNotFound,
                Message = "Session was not found.",
            },
        };

        MxGatewaySessionException exception = Assert.Throws<MxGatewaySessionException>(
            reply.EnsureProtocolSuccess);

        Assert.Equal("session-missing", exception.SessionId);
        Assert.Equal(ProtocolStatusCode.SessionNotFound, exception.ProtocolStatus?.Code);
    }

    private static MxCommandReply ReadReplyFixture(string fileName)
    {
        DirectoryInfo directory = new(AppContext.BaseDirectory);
        while (directory is not null)
        {
            string path = Path.Combine(
                directory.FullName,
                "clients",
                "proto",
                "fixtures",
                "behavior",
                "command-replies",
                fileName);

            if (File.Exists(path))
            {
                return JsonParser.Default.Parse<MxCommandReply>(File.ReadAllText(path));
            }

            directory = directory.Parent!;
        }

        throw new FileNotFoundException(fileName);
    }
}