using System.IO;
using ClaudeDo.Data.Models;
using ClaudeDo.Localization;
using ClaudeDo.Ui.Localization;
using ClaudeDo.Ui.Services;
using ClaudeDo.Ui.ViewModels.Planning;

namespace ClaudeDo.Ui.Tests.ViewModels;

public class PlanningDiffViewModelTests
{
    public PlanningDiffViewModelTests()
    {
        var dir = AppContext.BaseDirectory;
        while (dir is not null && !Directory.Exists(Path.Combine(dir, "src", "ClaudeDo.Localization", "locales")))
            dir = Path.GetDirectoryName(dir);
        Loc.Current = new Localizer(
            LocaleStore.Load(Path.Combine(dir!, "src", "ClaudeDo.Localization", "locales")), "en");
    }

    private sealed class FakePlanningWorker : StubWorkerClient
    {
        public IReadOnlyList<SubtaskDiffDto> AggregateResult { get; set; } = Array.Empty<SubtaskDiffDto>();
        public CombinedDiffResultDto? CombinedResult { get; set; }

        public override Task<IReadOnlyList<SubtaskDiffDto>> GetPlanningAggregateAsync(string planningTaskId) =>
            Task.FromResult(AggregateResult);
        public override Task<CombinedDiffResultDto?> BuildPlanningIntegrationBranchAsync(string planningTaskId, string targetBranch) =>
            Task.FromResult(CombinedResult);
    }

    [Fact]
    public async Task InitializeAsync_PopulatesSubtasks()
    {
        var fake = new FakePlanningWorker
        {
            AggregateResult = new[]
            {
                new SubtaskDiffDto("s1", "First",  "branch-1", "base1", "head1", "+1 -0", "diff1"),
                new SubtaskDiffDto("s2", "Second", "branch-2", "base2", "head2", "+2 -1", "diff2"),
            }
        };
        var vm = new PlanningDiffViewModel(fake, "plan-1", "main");

        await vm.InitializeAsync();

        Assert.Equal(2, vm.Subtasks.Count);
        Assert.Equal(vm.Subtasks[0], vm.SelectedSubtask);
    }

    [Fact]
    public async Task SelectingSubtask_InGroupedMode_SetsDisplayedDiff()
    {
        var fake = new FakePlanningWorker
        {
            AggregateResult = new[]
            {
                new SubtaskDiffDto("s1", "First",  "b1", "base1", "head1", null, "DIFF-A"),
                new SubtaskDiffDto("s2", "Second", "b2", "base2", "head2", null, "DIFF-B"),
            }
        };
        var vm = new PlanningDiffViewModel(fake, "plan-1", "main");
        await vm.InitializeAsync();

        vm.SelectedSubtask = vm.Subtasks[1];

        Assert.Equal("DIFF-B", vm.DisplayedDiff);
    }

    [Fact]
    public async Task ToggleCombined_Success_DisplaysUnifiedDiff()
    {
        var fake = new FakePlanningWorker
        {
            AggregateResult = new[]
            {
                new SubtaskDiffDto("s1", "First", "b1", "base1", "head1", null, "DIFF-A"),
            },
            CombinedResult = new CombinedDiffResultDto(true, "integration-branch", "COMBINED-DIFF", null, null),
        };
        var vm = new PlanningDiffViewModel(fake, "plan-1", "main");
        await vm.InitializeAsync();

        vm.IsCombinedMode = true;

        // Wait for the async toggle command to complete
        var deadline = DateTime.UtcNow.AddSeconds(5);
        while (DateTime.UtcNow < deadline && vm.IsLoadingCombined)
            await Task.Delay(10);

        Assert.Equal("COMBINED-DIFF", vm.DisplayedDiff);
        Assert.Null(vm.CombinedWarning);
    }

    [Fact]
    public async Task ToggleCombined_Conflict_ShowsWarning()
    {
        var fake = new FakePlanningWorker
        {
            AggregateResult = new[]
            {
                new SubtaskDiffDto("s1", "First", "b1", "base1", "head1", null, "DIFF-A"),
            },
            CombinedResult = new CombinedDiffResultDto(false, null, null, "subtask-42", new[] { "a.cs", "b.cs" }),
        };
        var vm = new PlanningDiffViewModel(fake, "plan-1", "main");
        await vm.InitializeAsync();

        vm.IsCombinedMode = true;

        var deadline = DateTime.UtcNow.AddSeconds(5);
        while (DateTime.UtcNow < deadline && vm.IsLoadingCombined)
            await Task.Delay(10);

        Assert.NotNull(vm.CombinedWarning);
        Assert.Contains("subtask-42", vm.CombinedWarning);
        Assert.Contains("2 files", vm.CombinedWarning);
    }

    [Fact]
    public async Task ToggleCombined_HubReturnsNull_ShowsError()
    {
        var fake = new FakePlanningWorker
        {
            AggregateResult = new[]
            {
                new SubtaskDiffDto("s1", "First", "b1", "base1", "head1", null, "DIFF-A"),
            },
            CombinedResult = null,
        };
        var vm = new PlanningDiffViewModel(fake, "plan-1", "main");
        await vm.InitializeAsync();

        vm.IsCombinedMode = true;

        var deadline = DateTime.UtcNow.AddSeconds(5);
        while (DateTime.UtcNow < deadline && vm.IsLoadingCombined)
            await Task.Delay(10);

        Assert.NotNull(vm.CombinedWarning);
        Assert.NotEmpty(vm.CombinedWarning!);
    }
}