using System.Diagnostics;
using FluentAssertions;
using FreeCode.Lsp;
using Xunit;

namespace FreeCode.Tests.Integration;

public sealed class LspIntegrationTests
{
    [Fact]
    public async Task InitializeAsync_CompletesWithoutError()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        var act = () => sut.InitializeAsync();

        await act.Should().NotThrowAsync();
    }

    [Fact]
    public async Task ShutdownAsync_CompletesWithoutError()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        var act = () => sut.ShutdownAsync();

        await act.Should().NotThrowAsync();
    }

    [Fact]
    public void IsConnected_InitiallyFalse()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        sut.IsConnected.Should().BeFalse();
    }

    [Fact]
    public void GetServerForFile_NoServers_ReturnsNull()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        sut.GetServerForFile("test.cs").Should().BeNull();
    }

    [Fact]
    public async Task EnsureServerStartedAsync_NoServer_ReturnsNull()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        var server = await sut.EnsureServerStartedAsync("test.cs");

        server.Should().BeNull();
    }

    [Fact]
    public void RegisterServer_RegistersExtensions()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        sut.RegisterServer("csharp", CreateStartInfo(), ".cs");

        sut.GetServerForFile("test.cs").Should().BeOfType<LspServerInstance>();
    }

    [Fact]
    public void GetServerForFile_MultipleExtensions_RoutesCorrectly()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        sut.RegisterServer("polyglot", CreateStartInfo(), ".cs", ".ts");

        var csharpServer = sut.GetServerForFile("test.cs");
        var typescriptServer = sut.GetServerForFile("test.ts");

        csharpServer.Should().NotBeNull();
        typescriptServer.Should().NotBeNull();
        csharpServer.Should().BeSameAs(typescriptServer);
    }

    [Fact]
    public void GetAllServers_InitiallyEmpty()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        sut.GetAllServers().Should().BeEmpty();
    }

    [Fact]
    public void GetAllServers_AfterRegistration_ContainsServer()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        sut.RegisterServer("csharp", CreateStartInfo(), ".cs");

        sut.GetAllServers().Should().ContainKey("csharp");
    }

    [Fact]
    public async Task OpenFileAsync_NoRegisteredServer_NoThrow()
    {
        using var testHome = new TestHomeDirectoryScope();
        var sut = new LspClientManager();

        var act = () => sut.OpenFileAsync("test.cs", "class C {}");

        await act.Should().NotThrowAsync();
    }

    private static ProcessStartInfo CreateStartInfo()
        => new()
        {
            FileName = "/bin/zsh",
            Arguments = "-lc \"exit 0\"",
            UseShellExecute = false,
            RedirectStandardInput = true,
            RedirectStandardOutput = true,
            RedirectStandardError = true,
            CreateNoWindow = true
        };
}