package torrent

import (
	"fmt"

	mapset "github.com/deckarep/golang-set/v2"
)

func (t *TorrentManager) getUncachedTorrents() ([]*Torrent, error) {
	t.log.Debug("Checking if torrents are still cached")
	allTorrents, _ := t.DirectoryMap.Get(INT_ALL)

	var hashGroups []mapset.Set[string]
	const maxGroupSize = 399

	currentGroup := mapset.NewSet[string]()
	hashGroups = append(hashGroups, currentGroup)

	allTorrents.IterCb(func(_ string, torrent *Torrent) {
		if torrent.AnyInProgress() || torrent.UnrepairableReason != "" {
			return
		}

		if currentGroup.Cardinality() >= maxGroupSize {
			currentGroup = mapset.NewSet[string]()
			hashGroups = append(hashGroups, currentGroup)
		}
		currentGroup.Add(torrent.Hash)
	})

	var availabilityChecks = make(map[string]bool)
	for i := range hashGroups {
		if hashGroups[i].Cardinality() == 0 {
			break
		}

		resp, err := t.Api.AvailabilityCheck(hashGroups[i].ToSlice())
		if err != nil {
			return nil, fmt.Errorf("availability check is incomplete, skipping uncached check: %v", err)
		}
		for hash, hosterHash := range resp {
			// Check if HosterHash is a map (Variants field is used)
			availabilityChecks[hash] = len(hosterHash.Variants) > 0
		}
	}

	var uncachedTorrents []*Torrent
	allTorrents.IterCb(func(_ string, torrent *Torrent) {
		if torrent.AnyInProgress() || torrent.UnrepairableReason != "" {
			return
		}

		if _, ok := availabilityChecks[torrent.Hash]; !ok || !availabilityChecks[torrent.Hash] {
			t.log.Debugf("Torrent %s is no longer cached, adding to repair list", t.GetKey(torrent))
			uncachedTorrents = append(uncachedTorrents, torrent)
		}
	})
	t.log.Debugf("Found %d torrents that are no longer cached", len(uncachedTorrents))

	return uncachedTorrents, nil
}