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

namespace TheLivingWorld.Tests;

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

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

    [Fact]
    public async Task CountAsync_is_zero_when_the_root_is_missing()
    {
        Assert.Equal(0, await _store.CountAsync());
        Assert.Empty(await _store.ListAsync());
    }

    [Fact]
    public async Task CountAsync_and_ListAsync_track_saved_summaries()
    {
        await _store.SaveSummaryAsync(Summary("alpha-11111111", "Alpha"));
        await _store.SaveSummaryAsync(Summary("bravo-22222222", "Bravo"));

        Assert.Equal(2, await _store.CountAsync());

        var listed = await _store.ListAsync();
        Assert.Equal(2, listed.Count);
        Assert.Equal(["Bravo", "Alpha"], listed.Select(world => world.Name).ToArray());
    }

    [Fact]
    public async Task CountAsync_ignores_directories_without_readable_state()
    {
        await _store.SaveSummaryAsync(Summary("alpha-11111111", "Alpha"));
        Directory.CreateDirectory(Path.Combine(_root, "not-a-valid-id!!!"));
        Directory.CreateDirectory(Path.Combine(_root, "orphan-33333333"));

        Assert.Equal(1, await _store.CountAsync());
    }

    [Fact]
    public async Task TryUpdateSummaryAsync_writes_over_an_existing_state_file()
    {
        var summary = Summary("alpha-11111111", "Alpha");
        await _store.SaveSummaryAsync(summary);

        Assert.True(await _store.TryUpdateSummaryAsync(summary with { Name = "Renamed" }));
        Assert.Equal("Renamed", (await _store.GetSummaryAsync(summary.Id))?.Name);
    }

    [Fact]
    public async Task TryUpdateSummaryAsync_refuses_to_recreate_a_deleted_world()
    {
        var summary = Summary("alpha-11111111", "Alpha");
        await _store.SaveSummaryAsync(summary);
        Assert.True(_store.Delete(summary.Id));

        Assert.False(await _store.TryUpdateSummaryAsync(summary));
        Assert.False(Directory.Exists(Path.Combine(_root, summary.Id)));
        Assert.Equal(0, await _store.CountAsync());
    }

    [Fact]
    public async Task SaveSummaryAsync_leaves_no_scratch_files_behind()
    {
        var summary = Summary("alpha-11111111", "Alpha");
        await _store.SaveSummaryAsync(summary);
        await _store.SaveSummaryAsync(summary with { Name = "Alpha again" });

        var files = Directory.GetFiles(Path.Combine(_root, summary.Id));
        Assert.Equal(["state.json"], files.Select(static path => Path.GetFileName(path)).Order().ToArray()!);
    }

    private static StoredWorldDto Summary(string id, string name) => new()
    {
        Id = id,
        Name = name,
        Latitude = 31.9,
        Longitude = -100.5,
        SizeMeters = 10_000,
        Status = WorldStatus.Ready,
        CreatedAt = DateTimeOffset.UtcNow,
    };

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