using VisionHost.Contracts;
using VisionHost.Runtime;
using Xunit;

namespace VisionHost.Runtime.Tests;

public sealed class RunServiceAcceptanceTests
{
    private static (RunService run, StubFrameSource cam, ScriptedConfirm confirm) New(
        IEnumerable<bool>? start = null,
        IEnumerable<bool>? stop = null)
    {
        var cam = new StubFrameSource();
        var confirm = new ScriptedConfirm(start, stop);
        var run = new RunService(cam, cam, new StubInspectService(), new StubPlcIo(), confirm);
        return (run, cam, confirm);
    }

    [Fact]
    public void Disconnected_StartDisabled_NoConfirm()
    {
        var (run, cam, confirm) = New();
        cam.SetConnection(ConnectionState.Disconnected);
        var s = run.Snapshot();
        Assert.Equal(RunState.Disconnected, s.RunState);
        Assert.Equal("断连", s.BadgeText);
        Assert.False(s.CanStart);
        Assert.Equal("未连接", s.ConnectionText);
        Assert.False(run.RequestStart());
        Assert.Equal(0, confirm.StartPrompts);
        run.Dispose();
    }

    [Fact]
    public void Reconnecting_StartDisabled_NoConfirm()
    {
        var (run, cam, confirm) = New();
        cam.SetConnection(ConnectionState.Reconnecting);
        Assert.False(run.Snapshot().CanStart);
        Assert.False(run.RequestStart());
        Assert.Equal(0, confirm.StartPrompts);
        run.Dispose();
    }

    [Fact]
    public void Start_CancelKeepsIdle()
    {
        var (run, _, confirm) = New(start: new[] { false });
        Assert.True(run.Snapshot().CanStart);
        Assert.False(run.RequestStart());
        Assert.Equal(1, confirm.StartPrompts);
        Assert.False(run.Snapshot().IsRunning);
        Assert.Equal(RunState.Idle, run.Snapshot().RunState);
        run.Dispose();
    }

    [Fact]
    public async Task Start_Confirm_ClearsCounts_AndRuns()
    {
        var (run, _, _) = New(start: new[] { true }, stop: new[] { true });
        Assert.True(run.RequestStart());
        await WaitAsync(() => run.Snapshot().TotalCount >= 1);
        var mid = run.Snapshot();
        Assert.True(mid.IsRunning);
        Assert.True(mid.CanStop);
        Assert.False(mid.CanStart);
        Assert.True(run.RequestStop());
        Assert.True(mid.TotalCount >= 1);

        var confirm2 = new ScriptedConfirm(new[] { true }, new[] { true });
        run.Dispose();
        var cam = new StubFrameSource();
        var run2 = new RunService(cam, cam, new StubInspectService(), new StubPlcIo(), confirm2);
        Assert.True(run2.RequestStart());
        Assert.Equal(0, run2.Snapshot().OkCount);
        Assert.Equal(0, run2.Snapshot().NgCount);
        run2.Dispose();
    }

    [Fact]
    public async Task Stop_CancelKeepsRunning_ConfirmKeepsCounts()
    {
        var confirm = new ScriptedConfirm(start: new[] { true }, stop: new[] { false, true });
        var cam = new StubFrameSource();
        using var run = new RunService(cam, cam, new StubInspectService(), new StubPlcIo(), confirm);
        Assert.True(run.RequestStart());
        await WaitAsync(() => run.Snapshot().TotalCount >= 2);
        var before = run.Snapshot().TotalCount;
        Assert.False(run.RequestStop());
        Assert.True(run.Snapshot().IsRunning);
        Assert.Equal(1, confirm.StopPrompts);
        Assert.True(run.RequestStop());
        var after = run.Snapshot();
        Assert.False(after.IsRunning);
        Assert.True(after.TotalCount >= before);
        Assert.True(after.CanStart);
        Assert.False(after.CanStop);
    }

    [Fact]
    public async Task FifthShot_IsNgStub()
    {
        var (run, _, _) = New(start: new[] { true }, stop: new[] { true });
        run.RequestStart();
        await WaitAsync(() => run.Snapshot().LastResultText == "NG STUB" && run.Snapshot().NgCount >= 1, 5000);
        var s = run.Snapshot();
        Assert.Equal("NG STUB", s.LastResultText);
        Assert.Equal("NG", s.BadgeText);
        Assert.True(s.NgCount >= 1);
        run.RequestStop();
        run.Dispose();
    }

    [Fact]
    public void LastResult_Dash_WhenNoShot()
    {
        var (run, _, _) = New();
        Assert.Equal("—", run.Snapshot().LastResultText);
        run.Dispose();
    }

    [Fact]
    public void LastResult_NgWithoutCode_IsNgOnly()
    {
        var cam = new StubFrameSource();
        var inspect = new FixedInspect(new InspectResult(false, null, 1, null));
        using var run = new RunService(cam, cam, inspect, new StubPlcIo(), new AlwaysConfirm());
        run.RequestStart();
        cam.GetType(); // keep
        // inject via queue by starting grab
        WaitAsync(() => run.Snapshot().TotalCount >= 1).GetAwaiter().GetResult();
        Assert.Equal("NG", run.Snapshot().LastResultText);
        run.RequestStop();
    }

    [Fact]
    public void Alarm_WhileConnected_CanStopIfRunning()
    {
        var (run, _, _) = New(start: new[] { true });
        run.RequestStart();
        run.RaiseAlarm("光源异常");
        var s = run.Snapshot();
        Assert.Equal(RunState.Alarm, s.RunState);
        Assert.Equal("报警", s.BadgeText);
        Assert.Equal("光源异常", s.AlarmText);
        Assert.True(s.CanStop);
        run.Dispose();
    }

    [Fact]
    public void Disconnect_OverridesAlarm_StartDisabled()
    {
        var (run, cam, confirm) = New();
        run.RaiseAlarm("光源异常");
        cam.SetConnection(ConnectionState.Disconnected);
        var s = run.Snapshot();
        Assert.Equal(RunState.Disconnected, s.RunState);
        Assert.False(s.CanStart);
        Assert.False(run.RequestStart());
        Assert.Equal(0, confirm.StartPrompts);
        run.Dispose();
    }

    [Fact]
    public void Counts_PersistAcrossStop_ResetOnNextStart()
    {
        var confirm = new ScriptedConfirm(start: new[] { true, true }, stop: new[] { true });
        var cam = new StubFrameSource();
        using var run = new RunService(cam, cam, new StubInspectService(), new StubPlcIo(), confirm);
        run.RequestStart();
        WaitAsync(() => run.Snapshot().TotalCount >= 3).GetAwaiter().GetResult();
        run.RequestStop();
        var kept = run.Snapshot().TotalCount;
        Assert.True(kept >= 3);
        run.RequestStart();
        Assert.Equal(0, run.Snapshot().TotalCount);
    }

    private static async Task WaitAsync(Func<bool> pred, int ms = 3000)
    {
        var until = DateTime.UtcNow.AddMilliseconds(ms);
        while (DateTime.UtcNow < until)
        {
            if (pred()) return;
            await Task.Delay(20);
        }
        throw new TimeoutException("condition not met");
    }

    [Fact]
    public async Task Changed_FromWorker_PostsToUiDispatch()
    {
        var ui = new RecordingDispatch();
        using var vm = RunViewModel.CreateStub(new AlwaysConfirm(), ui);
        Assert.True(vm.Service.RequestStart());
        await WaitAsync(() => vm.TotalCount >= 1);
        Assert.True(ui.PostCount >= 1);
        vm.Service.RequestStop();
    }

    private sealed class RecordingDispatch : IUiDispatch
    {
        public int PostCount;

        public void Post(Action action)
        {
            PostCount++;
            action();
        }
    }

    private sealed class FixedInspect : IInspectService
    {
        private readonly InspectResult _r;
        public FixedInspect(InspectResult r) => _r = r;
        public Task<InspectResult> Inspect(object frameHandle, string recipeId, CancellationToken cancellationToken)
            => Task.FromResult(_r);
    }
}