using System;
using System.IO;
using Jellyfin.Plugin.WatchedTogether.Configuration;
using MediaBrowser.Common.Configuration;
using MediaBrowser.Model.Serialization;
using Moq;
using Xunit;

namespace Jellyfin.Plugin.WatchedTogether.Tests;

/// <summary>
/// Marks tests that read or write the process-wide <see cref="Plugin.Instance"/>, so xUnit runs
/// them serially rather than letting parallel classes clobber each other's configuration.
/// </summary>
[CollectionDefinition(nameof(PluginTestContext))]
public class PluginTestCollection : ICollectionFixture<object>
{
}

/// <summary>
/// Constructs a real <see cref="Plugin"/> backed by a temporary directory so that services reading
/// <see cref="Plugin.Instance"/> have configuration to work with, and cleans up afterwards.
/// </summary>
public sealed class PluginTestContext : IDisposable
{
    private readonly string _configDirectory;

    private PluginTestContext(Plugin plugin, string configDirectory)
    {
        Plugin = plugin;
        _configDirectory = configDirectory;
    }

    public Plugin Plugin { get; }

    public PluginConfiguration Configuration => Plugin.Configuration;

    public static PluginTestContext Create()
    {
        var dir = Path.Combine(Path.GetTempPath(), "wt-tests-" + Guid.NewGuid().ToString("N"));
        Directory.CreateDirectory(dir);

        // BasePlugin<T> derives its data folder from PluginsPath and its config file from
        // PluginConfigurationsPath, so both must resolve to a real directory.
        var paths = new Mock<IApplicationPaths>();
        paths.SetupGet(p => p.PluginConfigurationsPath).Returns(dir);
        paths.SetupGet(p => p.PluginsPath).Returns(dir);

        // BasePlugin persists configuration through the serializer; a stub keeps tests off disk
        // while still letting UpdateConfiguration succeed.
        var serializer = new Mock<IXmlSerializer>();
        serializer.Setup(s => s.DeserializeFromFile(It.IsAny<Type>(), It.IsAny<string>()))
            .Returns(new PluginConfiguration());

        var plugin = new Plugin(paths.Object, serializer.Object);

        return new PluginTestContext(plugin, dir);
    }

    public void Dispose()
    {
        try
        {
            if (Directory.Exists(_configDirectory))
            {
                Directory.Delete(_configDirectory, recursive: true);
            }
        }
        catch (IOException)
        {
            // A leftover temp directory is not worth failing a test over.
        }
    }
}