using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Extensions.Options;
using TheLivingWorld.Api.Simulation;
using TheLivingWorld.Api.Storage;
using TheLivingWorld.Core.Contracts;
using TheLivingWorld.Core.Simulation;

namespace TheLivingWorld.Tests;

public sealed class WorldSimulationHostTests : IDisposable
{
    private readonly string _root = Path.Combine(Path.GetTempPath(), $"tlw-sim-{Guid.NewGuid():n}");
    private readonly WorldStore _store;
    private readonly WorldSimulationHost _host;

    public WorldSimulationHostTests()
    {
        _store = new WorldStore(
            Options.Create(new WorldStorageOptions { RootDirectory = _root }),
            NullLogger<WorldStore>.Instance);
        _host = new WorldSimulationHost(_store, NullLogger<WorldSimulationHost>.Instance);
    }

    [Fact]
    public async Task Attach_hydrates_legacy_worlds_without_catch_up_from_created_at()
    {
        var legacy = new WorldSummaryDto
        {
            Id = "legacy-11111111",
            Name = "Legacy",
            Latitude = 31.9,
            Longitude = -100.5,
            SizeMeters = 10_000,
            Status = WorldStatus.Ready,
            CreatedAt = DateTimeOffset.UtcNow - TimeSpan.FromDays(30),
        };
        await _store.SaveSummaryAsync(legacy);

        // Mimic host startup hydration for worlds that lack a clock.
        var seeded = legacy with
        {
            Clock = WorldSimulation.DefaultClock(),
            LastTickedAt = DateTimeOffset.UtcNow,
        };
        await _store.SaveSummaryAsync(seeded);
        _host.Attach(seeded with { LastTickedAt = null }); // Attach without prior tick → no catch-up

        // Force attach path used for legacy: Create with catchUp false via AttachSeeded behaviour —
        // Attach with LastTickedAt null means catchUp is false.
        var clock = _host.TryGetClock(legacy.Id);
        Assert.NotNull(clock);
        Assert.Equal(GameTime.DefaultStart, clock.GameTime);
    }

    [Fact]
    public async Task UpdateClock_changes_pause_and_Detach_stops_simulation()
    {
        var summary = new WorldSummaryDto
        {
            Id = "ready-22222222",
            Name = "Ready",
            Latitude = 31.9,
            Longitude = -100.5,
            SizeMeters = 10_000,
            Status = WorldStatus.Ready,
            CreatedAt = DateTimeOffset.UtcNow,
            Clock = WorldSimulation.DefaultClock(),
            LastTickedAt = DateTimeOffset.UtcNow,
        };
        await _store.SaveSummaryAsync(summary);
        _host.Attach(summary);

        var paused = _host.UpdateClock(summary.Id, new UpdateClockRequest { Paused = true });
        Assert.True(paused.Paused);

        var scaled = _host.UpdateClock(summary.Id, new UpdateClockRequest { TimeScale = 3 });
        Assert.Equal(3, scaled.TimeScale);
        Assert.True(scaled.Paused);

        _host.Detach(summary.Id);
        Assert.False(_host.IsAttached(summary.Id));
        Assert.Null(_host.TryGetClock(summary.Id));
    }

    [Fact]
    public void Overlay_strips_last_ticked_at_for_api()
    {
        var summary = new WorldSummaryDto
        {
            Id = "ready-33333333",
            Name = "Ready",
            Latitude = 31.9,
            Longitude = -100.5,
            SizeMeters = 10_000,
            Status = WorldStatus.Ready,
            CreatedAt = DateTimeOffset.UtcNow,
            Clock = WorldSimulation.DefaultClock(),
            LastTickedAt = DateTimeOffset.UtcNow,
        };
        _host.Attach(summary);

        var overlaid = _host.Overlay(summary);
        Assert.NotNull(overlaid.Clock);
        Assert.Null(overlaid.LastTickedAt);
    }

    public void Dispose()
    {
        foreach (var id in new[] { "legacy-11111111", "ready-22222222", "ready-33333333" })
            _host.Detach(id);

        if (Directory.Exists(_root)) Directory.Delete(_root, recursive: true);
        GC.SuppressFinalize(this);
    }
}