using System;
using System.IO;
using Microsoft.Data.Sqlite;
using Xunit;
using ytLive.Services;
using ytLive.ViewModels;

namespace ytLive.Tests;

/// <summary>
/// Sync offsets ship at zero. A correction belongs to one camera on one desk, so a fresh profile must
/// not arrive with audio already shifted — a non-zero default would move every creator's voice to fix
/// one machine and would hide whether the fault is theirs or ours.
/// </summary>
// The view model below touches the static LayoutPathOverride, so it shares the layout collection.
[Collection("MainViewModelLayoutPath")]
public sealed class AudioSyncSettingsTests : IDisposable
{
    private readonly string _db = Path.Combine(Path.GetTempPath(), $"ytLlive-syncsettings-{Guid.NewGuid():N}.db");

    public void Dispose()
    {
        SqliteConnection.ClearAllPools();
        try { File.Delete(_db); } catch (IOException) { /* best effort */ }
    }

    [Fact]
    public void Both_offsets_start_at_zero_and_only_then_take_a_value()
    {
        using (var store = new LayoutStore(_db))
        {
            Assert.Equal(0, store.LoadMicSyncOffsetMs());          // opt-in, not pre-applied
            Assert.Equal(0, store.LoadAudioSyncOffsetMs());

            // A mic delay cannot be negative — advancing is the global offset's job.
            store.SaveMicSyncOffsetMs(-120);
            Assert.Equal(0, store.LoadMicSyncOffsetMs());

            store.SaveMicSyncOffsetMs(600);                        // beyond the slider's range
            Assert.Equal(500, store.LoadMicSyncOffsetMs());

            store.SaveMicSyncOffsetMs(240);
            store.SaveAudioSyncOffsetMs(-130);
        }

        using var reopened = new LayoutStore(_db);
        Assert.Equal(240, reopened.LoadMicSyncOffsetMs());
        Assert.Equal(-130, reopened.LoadAudioSyncOffsetMs());
    }

    /// <summary>
    /// A slider move is persisted as it happens. It used to ride the debounced layout save, so a value
    /// set seconds before closing the app was lost — which cost a record-and-measure cycle on 2026-11-12
    /// when a −130 ms offset vanished between two clips.
    /// </summary>
    [Fact]
    public void A_slider_move_survives_without_any_debounce_flush()
    {
        MainViewModel.LayoutPathOverride = _db;
        try
        {
            var vm = new MainViewModel();
            vm.AudioSyncOffsetMs = -130;
            vm.MicSyncOffsetMs = 240;

            using var store = new LayoutStore(_db);
            Assert.Equal(-130, store.LoadAudioSyncOffsetMs());
            Assert.Equal(240, store.LoadMicSyncOffsetMs());
        }
        finally
        {
            MainViewModel.LayoutPathOverride = null;
        }
    }
}