using System.Linq;
using System.Net;
using System.Reflection.Metadata;
using ParadoxSaveParser.WebAPI.BackgroundTasks;
using ParadoxSaveParser.WebAPI.Database;
using ParadoxSaveParser.WebAPI.HttpHelpers;
using ParadoxSaveParser.WebAPI.SaveDataFilters;

namespace ParadoxSaveParser.WebAPI.Routes;

public class UploadSaveHandler : RouteHandlerBase
{
    private readonly BackgroundJobManager _bgJobManager;
    private readonly Dictionary<Game, ISaveDataFilter> _saveFilters;

    public UploadSaveHandler(
        CancellationToken cancelAllToken, 
        BackgroundJobManager bgJobManager,
        Dictionary<Game, ISaveDataFilter> saveFilters) 
        : base(cancelAllToken)
    {
        _bgJobManager = bgJobManager;
        _saveFilters = saveFilters;
    }

    public override async Task<HttpStatusCode> HandleRequest(
        HttpListenerContext ctx, ContextLogger requestLogger)
    {
        string? contentType = ctx.Request.Headers.GetValues("Content-Type")?.FirstOrDefault();
        if (contentType != "application/octet-stream")
            return await ReturnHelper.ResponseError(ctx, requestLogger, _cancelAllToken,
                    new ErrorMessage(HttpStatusCode.BadRequest,
                $"Invalid request Content-Type: '{contentType}'"));

        var gameStrOrError = RequestHelper.GetQueryValue(ctx, "game");
        if (gameStrOrError.HasError)
            return await ReturnHelper.ResponseError(ctx, requestLogger, _cancelAllToken, gameStrOrError.Error!);

        if (!Enum.TryParse(gameStrOrError.Value, ignoreCase: true, out Game game))
            return await ReturnHelper.ResponseError(ctx, requestLogger, _cancelAllToken,
                new ErrorMessage(HttpStatusCode.BadRequest,
                    $"Invalid requested game: '{gameStrOrError.Value}'"));  
        var meta = await Program.DB.CreateMetadata(game);

        var saveFilePath = meta.GetSaveFilePath();
        await using (var saveFile = File.OpenWrite(saveFilePath))
        {
            await using (var remoteStream = ctx.Request.InputStream)
                await remoteStream.CopyToAsync(saveFile, _cancelAllToken);
        }
        await Program.DB.UpdateMetadataStatus(meta, SaveFileProcessingStatus.Uploaded);

        _bgJobManager.StartNewParsingOperation(meta, _saveFilters[meta.game], _cancelAllToken);
        dynamic responseData = new { meta.id };
        return await ReturnHelper.ResponseJson(ctx, requestLogger, _cancelAllToken, responseData);
    }
}