using System.Text.RegularExpressions;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using MonoTorrent;
using RdtClient.Data.Models.DebridClient;
using RdtClient.Data.Models.Internal;
using RdtClient.Service.BackgroundServices;
using RdtClient.Service.Helpers;
using RdtClient.Service.Services;
using Torrent = RdtClient.Data.Models.Data.Torrent;

namespace RdtClient.Web.Controllers;

[Authorize(Policy = "AuthSetting")]
[Route("Api/Torrents")]
public class TorrentsController(ILogger<TorrentsController> logger, Torrents torrents, TorrentRunner torrentRunner, IRateLimitCoordinator coordinator) : Controller
{
    [HttpGet]
    [Route("")]
    public async Task<ActionResult<IList<TorrentDto>>> GetAll()
    {
        var results = await torrents.Get();

        var torrentDtos = results.Select(torrent => TorrentDtoMapper.ToListDto(torrent, torrents.GetDownloadStats))
                                 .ToList();

        return Ok(torrentDtos);
    }

    [HttpGet]
    [Route("Get/{torrentId:guid}")]
    public async Task<ActionResult<TorrentDto>> GetById(Guid torrentId)
    {
        var torrent = await torrents.GetById(torrentId);

        if (torrent == null)
        {
            return NotFound();
        }

        foreach (var file in torrent.Downloads)
        {
            file.Torrent = null;
        }

        var torrentDto = TorrentDtoMapper.ToDetailDto(torrent, torrents.GetDownloadStats);

        return Ok(torrentDto);
    }

    [HttpGet]
    [Route("DiskSpaceStatus")]
    public ActionResult<DiskSpaceStatus?> GetDiskSpaceStatus()
    {
        var status = DiskSpaceMonitor.GetCurrentStatus();

        return Ok(status);
    }

    [HttpGet]
    [Route("RateLimitStatus")]
    public ActionResult<RateLimitStatus> GetRateLimitStatus()
    {
        var nextDequeueTime = coordinator.GetMaxNextAllowedAt();

        if (nextDequeueTime == null || nextDequeueTime < DateTimeOffset.Now)
        {
            return Ok(new RateLimitStatus
            {
                NextDequeueTime = null,
                SecondsRemaining = 0
            });
        }

        return Ok(new RateLimitStatus
        {
            NextDequeueTime = nextDequeueTime,
            SecondsRemaining = (nextDequeueTime.Value - DateTimeOffset.Now).TotalSeconds
        });
    }

    /// <summary>
    ///     Used for debugging only. Force a tick.
    /// </summary>
    /// <returns></returns>
    [HttpGet]
    [Route("Tick")]
    public async Task<ActionResult> Tick()
    {
        await torrentRunner.Tick();

        return Ok();
    }

    [HttpPost]
    [Route("UploadFile")]
    public async Task<ActionResult> UploadFile([FromForm] IFormFile? file,
                                               [ModelBinder(BinderType = typeof(JsonModelBinder))]
                                               TorrentControllerUploadFileRequest? formData)
    {
        if (file == null || file.Length <= 0)
        {
            return BadRequest("Invalid torrent file");
        }

        if (formData?.Torrent == null)
        {
            return BadRequest("Invalid Torrent");
        }

        logger.LogDebug($"Add file");

        var bytes = await ReadFormFileBytes(file);

        await torrents.AddFileToDebridQueue(bytes, formData.Torrent);

        return Ok();
    }

    [HttpPost]
    [Route("UploadMagnet")]
    public async Task<ActionResult> UploadMagnet([FromBody] TorrentControllerUploadMagnetRequest? request)
    {
        if (request == null)
        {
            return BadRequest();
        }

        if (String.IsNullOrEmpty(request.MagnetLink))
        {
            return BadRequest("Invalid magnet link");
        }

        if (request.Torrent == null)
        {
            return BadRequest("Invalid Torrent");
        }

        logger.LogDebug($"Add magnet");

        await torrents.AddMagnetToDebridQueue(request.MagnetLink, request.Torrent);

        return Ok();
    }

    [HttpPost]
    [Route("UploadNzbFile")]
    public async Task<ActionResult> UploadNzbFile([FromForm] IFormFile? file,
                                                  [ModelBinder(BinderType = typeof(JsonModelBinder))]
                                                  TorrentControllerUploadFileRequest? formData)
    {
        if (file == null || file.Length <= 0)
        {
            return BadRequest("Invalid nzb file");
        }

        if (formData?.Torrent == null)
        {
            return BadRequest("Invalid Torrent");
        }

        logger.LogDebug($"Add nzb file");

        if (String.IsNullOrWhiteSpace(formData.Torrent.RdName))
        {
            formData.Torrent.RdName = file.FileName;
        }

        var bytes = await ReadFormFileBytes(file);

        await torrents.AddNzbFileToDebridQueue(bytes, file.FileName, formData.Torrent);

        return Ok();
    }

    [HttpPost]
    [Route("UploadNzbLink")]
    public async Task<ActionResult> UploadNzbLink([FromBody] TorrentControllerUploadNzbLinkRequest? request)
    {
        if (request == null)
        {
            return BadRequest();
        }

        if (String.IsNullOrEmpty(request.NzbLink))
        {
            return BadRequest("Invalid nzb link");
        }

        if (request.Torrent == null)
        {
            return BadRequest("Invalid Torrent");
        }

        logger.LogDebug($"Add nzb link {request.NzbLink}");

        await torrents.AddNzbLinkToDebridQueue(request.NzbLink, request.Torrent);

        return Ok();
    }

    [HttpPost]
    [Route("CheckFiles")]
    public async Task<ActionResult> CheckFiles([FromForm] IFormFile? file)
    {
        if (file == null || file.Length <= 0)
        {
            return BadRequest("Invalid torrent file");
        }

        var bytes = await ReadFormFileBytes(file);

        var torrent = await MonoTorrent.Torrent.LoadAsync(bytes);

        var result = await torrents.GetAvailableFiles(torrent.InfoHashes.V1OrV2.ToHex());

        return Ok(result);
    }

    [HttpPost]
    [Route("CheckFilesMagnet")]
    public async Task<ActionResult> CheckFilesMagnet([FromBody] TorrentControllerCheckFilesRequest? request)
    {
        if (request == null)
        {
            return BadRequest();
        }

        if (String.IsNullOrEmpty(request.MagnetLink))
        {
            return BadRequest("MagnetLink cannot be null or empty");
        }

        var magnet = MagnetLink.Parse(request.MagnetLink);

        var result = await torrents.GetAvailableFiles(magnet.InfoHashes.V1OrV2.ToHex());

        return Ok(result);
    }

    [HttpPost]
    [Route("Delete/{torrentId:guid}")]
    public async Task<ActionResult> Delete(Guid torrentId, [FromBody] TorrentControllerDeleteRequest? request)
    {
        if (request == null)
        {
            return BadRequest();
        }

        logger.LogDebug("Delete {torrentId}", torrentId);

        await torrents.Delete(torrentId, request.DeleteData, request.DeleteRdTorrent, request.DeleteLocalFiles);

        return Ok();
    }

    [HttpPost]
    [Route("Retry/{torrentId:guid}")]
    public async Task<ActionResult> Retry(Guid torrentId)
    {
        logger.LogDebug("Retry {torrentId}", torrentId);

        await torrents.UpdateRetry(torrentId, DateTimeOffset.UtcNow, 0);
        await torrents.RetryTorrent(torrentId, 0);

        return Ok();
    }

    [HttpPost]
    [Route("RetryDownload/{downloadId:guid}")]
    public async Task<ActionResult> RetryDownload(Guid downloadId)
    {
        logger.LogDebug("Retry download {downloadId}", downloadId);

        await torrents.RetryDownload(downloadId);

        return Ok();
    }

    [HttpPut]
    [Route("Update")]
    public async Task<ActionResult> Update([FromBody] Torrent? torrent)
    {
        if (torrent == null)
        {
            return BadRequest();
        }

        await torrents.Update(torrent);

        return Ok();
    }

    [HttpPost]
    [Route("VerifyRegex")]
    public async Task<ActionResult> VerifyRegex([FromForm] IFormFile? file, [FromBody] TorrentControllerVerifyRegexRequest? request)
    {
        if (request == null)
        {
            return Ok();
        }

        var includeError = "";
        var excludeError = "";

        IList<DebridClientAvailableFile> availableFiles;

        if (!String.IsNullOrWhiteSpace(request.MagnetLink))
        {
            var magnet = MagnetLink.Parse(request.MagnetLink);

            availableFiles = await torrents.GetAvailableFiles(magnet.InfoHashes.V1OrV2.ToHex());
        }
        else if (file != null)
        {
            var bytes = await ReadFormFileBytes(file);

            var torrent = await MonoTorrent.Torrent.LoadAsync(bytes);

            availableFiles = await torrents.GetAvailableFiles(torrent.InfoHashes.V1OrV2.ToHex());
        }
        else
        {
            return BadRequest();
        }

        var selectedFiles = new List<DebridClientAvailableFile>();

        if (!String.IsNullOrWhiteSpace(request.IncludeRegex))
        {
            var includeRegex = BuildRegex(request.IncludeRegex, out includeError);

            if (includeRegex != null)
            {
                foreach (var availableFile in availableFiles)
                {
                    if (includeRegex.IsMatch(availableFile.Filename))
                    {
                        selectedFiles.Add(availableFile);
                    }
                }
            }
        }
        else if (!String.IsNullOrWhiteSpace(request.ExcludeRegex))
        {
            var excludeRegex = BuildRegex(request.ExcludeRegex, out excludeError);

            if (excludeRegex != null)
            {
                foreach (var availableFile in availableFiles)
                {
                    if (!excludeRegex.IsMatch(availableFile.Filename))
                    {
                        selectedFiles.Add(availableFile);
                    }
                }
            }
        }
        else
        {
            selectedFiles = [.. availableFiles];
        }

        return Ok(new
        {
            includeError,
            excludeError,
            selectedFiles
        });
    }

    private static Regex? BuildRegex(String pattern, out String error)
    {
        try
        {
            error = "";

            return new(pattern, RegexOptions.Compiled);
        }
        catch (Exception ex)
        {
            error = ex.Message;

            return null;
        }
    }

    private static async Task<Byte[]> ReadFormFileBytes(IFormFile file)
    {
        await using var fileStream = file.OpenReadStream();
        await using var memoryStream = file.Length is > 0 and <= Int32.MaxValue ? new((Int32)file.Length) : new MemoryStream();

        await fileStream.CopyToAsync(memoryStream);

        return memoryStream.ToArray();
    }
}

public class TorrentControllerUploadFileRequest
{
    public Torrent? Torrent { get; set; }
}

public class TorrentControllerUploadMagnetRequest
{
    public String? MagnetLink { get; set; }
    public Torrent? Torrent { get; set; }
}

public class TorrentControllerUploadNzbLinkRequest
{
    public String? NzbLink { get; set; }
    public Torrent? Torrent { get; set; }
}

public class TorrentControllerDeleteRequest
{
    public Boolean DeleteData { get; set; }
    public Boolean DeleteRdTorrent { get; set; }
    public Boolean DeleteLocalFiles { get; set; }
}

public class TorrentControllerCheckFilesRequest
{
    public String? MagnetLink { get; set; }
}

public class TorrentControllerVerifyRegexRequest
{
    public String? IncludeRegex { get; set; }
    public String? ExcludeRegex { get; set; }
    public String? MagnetLink { get; set; }
}