// Copyright (c) 2021 - 2023, Ludvig Lundgren and the autobrr contributors.
// SPDX-License-Identifier: GPL-2.0-or-later

package action

import (
	"context"
	"encoding/base64"
	"os"
	"time"

	"github.com/autobrr/autobrr/internal/domain"
	"github.com/autobrr/autobrr/pkg/errors"

	delugeClient "github.com/gdm85/go-libdeluge"
)

func (s *service) deluge(ctx context.Context, action *domain.Action, release domain.Release) ([]string, error) {
	s.log.Debug().Msgf("action Deluge: %s", action.Name)

	var err error

	// get client for action
	client, err := s.clientSvc.FindByID(ctx, action.ClientID)
	if err != nil {
		s.log.Error().Stack().Err(err).Msgf("error finding client: %d", action.ClientID)
		return nil, err
	}

	if client == nil {
		return nil, errors.New("could not find client by id: %d", action.ClientID)
	}

	var rejections []string

	switch client.Type {
	case "DELUGE_V1":
		rejections, err = s.delugeV1(ctx, client, action, release)

	case "DELUGE_V2":
		rejections, err = s.delugeV2(ctx, client, action, release)
	}

	return rejections, err
}

func (s *service) delugeCheckRulesCanDownload(deluge delugeClient.DelugeClient, client *domain.DownloadClient, action *domain.Action) ([]string, error) {
	s.log.Trace().Msgf("action Deluge: %v check rules", action.Name)

	// check for active downloads and other rules
	if client.Settings.Rules.Enabled && !action.IgnoreRules {
		activeDownloads, err := deluge.TorrentsStatus(delugeClient.StateDownloading, nil)
		if err != nil {
			return nil, errors.Wrap(err, "could not fetch downloading torrents")
		}

		// make sure it's not set to 0 by default
		if client.Settings.Rules.MaxActiveDownloads > 0 {

			// if max active downloads reached, check speed and if lower than threshold add anyway
			if len(activeDownloads) >= client.Settings.Rules.MaxActiveDownloads {
				s.log.Debug().Msg("max active downloads reached, skipping")

				rejections := []string{"max active downloads reached, skipping"}
				return rejections, nil

				//	// TODO handle ignore slow torrents
				//if client.Settings.Rules.IgnoreSlowTorrents {
				//
				//	// get session state
				//	// gives type conversion errors
				//	state, err := deluge.GetSessionStatus()
				//	if err != nil {
				//		s.log.Error().Err(err).Msg("could not get session state")
				//		return err
				//	}
				//
				//	if int64(state.DownloadRate)*1024 >= client.Settings.Rules.DownloadSpeedThreshold {
				//		s.log.Trace().Msg("max active downloads reached, skip adding")
				//		return nil
				//	}
				//
				//	s.log.Trace().Msg("active downloads are slower than set limit, lets add it")
				//}
			}
		}
	}

	return nil, nil
}

func (s *service) delugeV1(ctx context.Context, client *domain.DownloadClient, action *domain.Action, release domain.Release) ([]string, error) {
	settings := delugeClient.Settings{
		Hostname:             client.Host,
		Port:                 uint(client.Port),
		Login:                client.Username,
		Password:             client.Password,
		DebugServerResponses: true,
		ReadWriteTimeout:     time.Second * 20,
	}

	deluge := delugeClient.NewV1(settings)

	// perform connection to Deluge server
	err := deluge.Connect()
	if err != nil {
		return nil, errors.Wrap(err, "could not connect to client %s at %s", client.Name, client.Host)
	}

	defer deluge.Close()

	// perform connection to Deluge server
	rejections, err := s.delugeCheckRulesCanDownload(deluge, client, action)
	if err != nil {
		s.log.Error().Err(err).Msgf("error checking client rules: %s", action.Name)
		return nil, err
	}
	if rejections != nil {
		return rejections, nil
	}

	if release.HasMagnetUri() {
		options, err := s.prepareDelugeOptions(action)
		if err != nil {
			return nil, errors.Wrap(err, "could not prepare options")
		}

		s.log.Trace().Msgf("action Deluge options: %+v", options)

		torrentHash, err := deluge.AddTorrentMagnet(release.MagnetURI, &options)
		if err != nil {
			return nil, errors.Wrap(err, "could not add torrent magnet %s to client: %s", release.TorrentURL, client.Name)
		}

		if action.Label != "" {
			labelPluginActive, err := deluge.LabelPlugin()
			if err != nil {
				return nil, errors.Wrap(err, "could not load label plugin for client: %s", client.Name)
			}

			if labelPluginActive != nil {
				// TODO first check if label exists, if not, add it, otherwise set
				err = labelPluginActive.SetTorrentLabel(torrentHash, action.Label)
				if err != nil {
					return nil, errors.Wrap(err, "could not set label: %s on client: %s", action.Label, client.Name)
				}
			}
		}

		s.log.Info().Msgf("torrent from magnet with hash %s successfully added to client: '%s'", torrentHash, client.Name)

		return nil, nil
	} else {
		if release.TorrentTmpFile == "" {
			if err := release.DownloadTorrentFileCtx(ctx); err != nil {
				s.log.Error().Err(err).Msgf("could not download torrent file for release: %s", release.TorrentName)
				return nil, err
			}
		}

		t, err := os.ReadFile(release.TorrentTmpFile)
		if err != nil {
			return nil, errors.Wrap(err, "could not read torrent file: %s", release.TorrentTmpFile)
		}

		// encode file to base64 before sending to deluge
		encodedFile := base64.StdEncoding.EncodeToString(t)
		if encodedFile == "" {
			return nil, errors.Wrap(err, "could not encode torrent file: %s", release.TorrentTmpFile)
		}

		options, err := s.prepareDelugeOptions(action)
		if err != nil {
			return nil, errors.Wrap(err, "could not prepare options")
		}

		s.log.Trace().Msgf("action Deluge options: %+v", options)

		torrentHash, err := deluge.AddTorrentFile(release.TorrentTmpFile, encodedFile, &options)
		if err != nil {
			return nil, errors.Wrap(err, "could not add torrent %v to client: %v", release.TorrentTmpFile, client.Name)
		}

		if action.Label != "" {
			labelPluginActive, err := deluge.LabelPlugin()
			if err != nil {
				return nil, errors.Wrap(err, "could not load label plugin for client: %s", client.Name)
			}

			if labelPluginActive != nil {
				// TODO first check if label exists, if not, add it, otherwise set
				err = labelPluginActive.SetTorrentLabel(torrentHash, action.Label)
				if err != nil {
					return nil, errors.Wrap(err, "could not set label: %v on client: %s", action.Label, client.Name)
				}
			}
		}

		s.log.Info().Msgf("torrent with hash %s successfully added to client: '%s'", torrentHash, client.Name)
	}

	return nil, nil
}

func (s *service) delugeV2(ctx context.Context, client *domain.DownloadClient, action *domain.Action, release domain.Release) ([]string, error) {
	settings := delugeClient.Settings{
		Hostname:             client.Host,
		Port:                 uint(client.Port),
		Login:                client.Username,
		Password:             client.Password,
		DebugServerResponses: true,
		ReadWriteTimeout:     time.Second * 20,
	}

	deluge := delugeClient.NewV2(settings)

	// perform connection to Deluge server
	err := deluge.Connect()
	if err != nil {
		return nil, errors.Wrap(err, "could not connect to client %s at %s", client.Name, client.Host)
	}

	defer deluge.Close()

	// perform connection to Deluge server
	rejections, err := s.delugeCheckRulesCanDownload(deluge, client, action)
	if err != nil {
		s.log.Error().Err(err).Msgf("error checking client rules: %s", action.Name)
		return nil, err
	}
	if rejections != nil {
		return rejections, nil
	}

	if release.HasMagnetUri() {
		options, err := s.prepareDelugeOptions(action)
		if err != nil {
			return nil, errors.Wrap(err, "could not prepare options")
		}

		s.log.Trace().Msgf("action Deluge options: %+v", options)

		torrentHash, err := deluge.AddTorrentMagnet(release.MagnetURI, &options)
		if err != nil {
			return nil, errors.Wrap(err, "could not add torrent magnet %s to client: %s", release.TorrentURL, client.Name)
		}

		if action.Label != "" {
			labelPluginActive, err := deluge.LabelPlugin()
			if err != nil {
				return nil, errors.Wrap(err, "could not load label plugin for client: %s", client.Name)
			}

			if labelPluginActive != nil {
				// TODO first check if label exists, if not, add it, otherwise set
				err = labelPluginActive.SetTorrentLabel(torrentHash, action.Label)
				if err != nil {
					return nil, errors.Wrap(err, "could not set label: %s on client: %s", action.Label, client.Name)
				}
			}
		}

		s.log.Info().Msgf("torrent with hash %s successfully added to client: '%s'", torrentHash, client.Name)

		return nil, nil
	} else {
		if release.TorrentTmpFile == "" {
			if err := release.DownloadTorrentFileCtx(ctx); err != nil {
				s.log.Error().Err(err).Msgf("could not download torrent file for release: %s", release.TorrentName)
				return nil, err
			}
		}

		t, err := os.ReadFile(release.TorrentTmpFile)
		if err != nil {
			return nil, errors.Wrap(err, "could not read torrent file: %s", release.TorrentTmpFile)
		}

		// encode file to base64 before sending to deluge
		encodedFile := base64.StdEncoding.EncodeToString(t)
		if encodedFile == "" {
			return nil, errors.Wrap(err, "could not encode torrent file: %s", release.TorrentTmpFile)
		}

		// set options
		options, err := s.prepareDelugeOptions(action)
		if err != nil {
			return nil, errors.Wrap(err, "could not prepare options")
		}

		s.log.Trace().Msgf("action Deluge options: %+v", options)

		torrentHash, err := deluge.AddTorrentFile(release.TorrentTmpFile, encodedFile, &options)
		if err != nil {
			return nil, errors.Wrap(err, "could not add torrent %s to client: %s", release.TorrentTmpFile, client.Name)
		}

		if action.Label != "" {
			labelPluginActive, err := deluge.LabelPlugin()
			if err != nil {
				return nil, errors.Wrap(err, "could not load label plugin for client: %s", client.Name)
			}

			if labelPluginActive != nil {
				// TODO first check if label exists, if not, add it, otherwise set
				err = labelPluginActive.SetTorrentLabel(torrentHash, action.Label)
				if err != nil {
					return nil, errors.Wrap(err, "could not set label: %s on client: %s", action.Label, client.Name)
				}
			}
		}

		s.log.Info().Msgf("torrent with hash %s successfully added to client: '%s'", torrentHash, client.Name)
	}

	return nil, nil
}

func (s *service) prepareDelugeOptions(action *domain.Action) (delugeClient.Options, error) {

	// set options
	options := delugeClient.Options{}

	if action.Paused {
		options.AddPaused = &action.Paused
	}
	if action.SavePath != "" {
		options.DownloadLocation = &action.SavePath
	}
	if action.LimitDownloadSpeed > 0 {
		maxDL := int(action.LimitDownloadSpeed)
		options.MaxDownloadSpeed = &maxDL
	}
	if action.LimitUploadSpeed > 0 {
		maxUL := int(action.LimitUploadSpeed)
		options.MaxUploadSpeed = &maxUL
	}

	return options, nil
}