package torrent

import (
	"github.com/debridmediamanager/zurg/pkg/realdebrid"
)

type LibraryState struct {
	TotalCount         int
	ActiveCount        int
	FirstTorrent       *realdebrid.Torrent
	FirstActiveTorrent *realdebrid.Torrent
}

func (ls LibraryState) equal(a LibraryState) bool {
	if a.TotalCount != ls.TotalCount || a.ActiveCount != ls.ActiveCount {
		return false
	}
	if (ls.FirstTorrent == nil) != (a.FirstTorrent == nil) {
		return false
	}
	if ls.FirstTorrent != nil && (ls.FirstTorrent.ID != a.FirstTorrent.ID || ls.FirstTorrent.Status != a.FirstTorrent.Status) {
		return false
	}
	if (ls.FirstActiveTorrent == nil) != (a.FirstActiveTorrent == nil) {
		return false
	}
	if ls.FirstActiveTorrent != nil && (ls.FirstActiveTorrent.ID != a.FirstActiveTorrent.ID || ls.FirstActiveTorrent.Status != a.FirstActiveTorrent.Status) {
		return false
	}
	return true
}

func (t *TorrentManager) SetNewLatestState(checksum LibraryState) {
	t.latestState.ActiveCount = checksum.ActiveCount
	t.latestState.TotalCount = checksum.TotalCount
	t.latestState.FirstTorrent = checksum.FirstTorrent
	t.latestState.FirstActiveTorrent = checksum.FirstActiveTorrent
}

type torrentsResp struct {
	torrents   []realdebrid.Torrent
	totalCount int
}

// generates a checksum based on the number of torrents, the first torrent id and the number of active torrents
func (t *TorrentManager) getCurrentState() LibraryState {
	torrentChan := make(chan torrentsResp, 1)
	activeChan := make(chan torrentsResp, 1)
	countChan := make(chan int, 1)
	errChan := make(chan error, 3) // accommodate errors from all goroutines
	defer close(torrentChan)
	defer close(activeChan)
	defer close(countChan)
	defer close(errChan)

	_ = t.workerPool.Submit(func() {
		torrents, totalCount, err := t.Api.GetTorrents(1, false)
		if err != nil {
			errChan <- err
			return
		}
		torrentChan <- torrentsResp{torrents: torrents, totalCount: totalCount}
	})

	_ = t.workerPool.Submit(func() {
		torrents, totalCount, err := t.Api.GetTorrents(1, true)
		if err != nil {
			errChan <- err
			return
		}
		activeChan <- torrentsResp{torrents: torrents, totalCount: totalCount}
	})

	_ = t.workerPool.Submit(func() {
		count, err := t.Api.GetActiveTorrentCount()
		if err != nil {
			errChan <- err
			return
		}
		countChan <- count.DownloadingCount
	})

	var first, active *realdebrid.Torrent
	var totalCount, count int

	for i := 0; i < 3; i++ {
		select {
		case firstResp := <-torrentChan:
			if len(firstResp.torrents) > 0 {
				first = &firstResp.torrents[0]
			}
			totalCount = firstResp.totalCount
		case activeResp := <-activeChan:
			if len(activeResp.torrents) > 0 {
				active = &activeResp.torrents[0]
			}
		case count = <-countChan:
		case err := <-errChan:
			t.log.Warnf("Checksum API Error: %v", err)
			return LibraryState{}
		}
	}

	return LibraryState{
		TotalCount:         totalCount,
		ActiveCount:        count,
		FirstTorrent:       first,
		FirstActiveTorrent: active,
	}
}