using System.IO.Compression;
using Mlaumcherb.Client.Avalonia.зримое;
using Mlaumcherb.Client.Avalonia.классы;
using Mlaumcherb.Client.Avalonia.холопы;

namespace Mlaumcherb.Client.Avalonia.сеть.TaskFactories;

public class MyModpackV1DownloadTaskFactory : INetworkTaskFactory
{
    private readonly GameVersionDescriptor _descriptor;
    private IOPath _modpackDescriptorPath;
    private IOPath _versionDir;
    private MyModpackV1? _modpack;
    // relative, absolute
    private Dictionary<IOPath, IOPath> _filesToDosnload = new();

    public MyModpackV1DownloadTaskFactory(GameVersionDescriptor descriptor)
    {
        _descriptor = descriptor;
        _modpackDescriptorPath = PathHelper.GetModpackDescriptorPath(_descriptor.id);
        _versionDir = PathHelper.GetVersionDir(_descriptor.id);
    }
    
    public async Task<NetworkTask?> CreateAsync(bool checkHashes)
    {
        if(_descriptor.modpack is null)
            throw new ArgumentNullException(nameof(_descriptor.modpack));
        
        (_modpack, bool didDownloadModpackDescriptor) = await NetworkHelper.ReadOrDownloadAndDeserialize<MyModpackV1>(
            _modpackDescriptorPath,
            _descriptor.modpack.artifact.url, 
            _descriptor.modpack.artifact.sha1,
            checkHashes);
        if (_modpack.format_version != _descriptor.modpack.format_version)
            throw new Exception($"Modpack.format_version mismatches descriptor.modpack.version: " +
                                $"{_modpack.format_version} != {_descriptor.modpack.format_version}");
        
        NetworkTask? networkTask = null;
        _filesToDosnload = _modpack.CheckFiles(_versionDir, checkHashes, didDownloadModpackDescriptor);
        if(_filesToDosnload.Count > 0)
        {
            networkTask = new NetworkTask(
                $"modpack '{_modpack.name}'",
                _modpack.zip.size,
                Download
            );
        }

        return networkTask;
    }

    private async Task Download(NetworkProgressReporter pr, CancellationToken ct)
    {
        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"started downloading modpack '{_modpack!.name}'");
        if(string.IsNullOrEmpty(_modpack.zip.url))
            throw new Exception($"modpack '{_modpack.name}' doesn't have a url to download");

        var _archivePath = Path.Concat(PathHelper.GetCacheDir(), "modpacks", _modpack.name + ".zip");
        await NetworkHelper.DownloadFile(_modpack.zip.url, _archivePath, ct, pr.AddBytesCount);
        
        await using var zipf = File.OpenRead(_archivePath);
        using var archive = new ZipArchive(zipf);
        foreach (var entry in archive.Entries)
        {
            IOPath relativePath = new(entry.FullName);
            if(_filesToDosnload.TryGetValue(relativePath, out var absolutePath))
            {
                Directory.Create(absolutePath.ParentDir());
                entry.ExtractToFile(absolutePath.ToString(), true);
            }
        }
        
        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"finished downloading modpack '{_modpack.name}'");
    }
}