Files
mal/internal/anime/recommendations/store.go

73 lines
1.6 KiB
Go

package recommendations
import (
"mal/internal/db"
"sort"
"sync"
)
type candidateStore struct {
watchlistAnimeIDs map[int]struct{}
byID map[int]rankedCandidate
mu sync.Mutex
}
func newCandidateStore(watchlist []db.GetUserWatchListRow) *candidateStore {
watchlistAnimeIDs := make(map[int]struct{}, len(watchlist))
for _, entry := range watchlist {
if entry.AnimeID <= 0 {
continue
}
watchlistAnimeIDs[int(entry.AnimeID)] = struct{}{}
}
return &candidateStore{
watchlistAnimeIDs: watchlistAnimeIDs,
byID: map[int]rankedCandidate{},
}
}
func (s *candidateStore) upsert(candidate rankedCandidate) {
if candidate.id <= 0 {
return
}
if _, exists := s.watchlistAnimeIDs[candidate.id]; exists {
return
}
s.mu.Lock()
defer s.mu.Unlock()
current, ok := s.byID[candidate.id]
if !ok {
s.byID[candidate.id] = candidate
return
}
current.collaborativeScore += candidate.collaborativeScore
current.profileSearchScore += candidate.profileSearchScore
if candidate.hasAnime {
current.anime = candidate.anime
current.hasAnime = true
}
s.byID[candidate.id] = current
}
func (s *candidateStore) ranked() []rankedCandidate {
ranked := make([]rankedCandidate, 0, len(s.byID))
for _, item := range s.byID {
ranked = append(ranked, item)
}
sort.Slice(ranked, func(i, j int) bool {
left := rankedCandidateRetrievalScore(ranked[i].collaborativeScore, ranked[i].profileSearchScore)
right := rankedCandidateRetrievalScore(ranked[j].collaborativeScore, ranked[j].profileSearchScore)
if left == right {
return ranked[i].id < ranked[j].id
}
return left > right
})
return ranked
}