// Package service — scraper orchestrator.
//
// ScraperService takes a Media row and tries to enrich it with metadata from
// local NFO first, then TMDb -> Douban -> Bangumi -> TheTVDB. Fanart.tv is
// artwork-only and upgrades poster/backdrop after a metadata match.
package service

import (
	"context"
	"strings"

	"go.uber.org/zap"

	"github.com/ShukeBta/MediaStationGo/internal/model"
)

// EnrichOne runs the provider chain for a single media row.
func (s *ScraperService) EnrichOne(ctx context.Context, m *model.Media) error {
	return s.EnrichOneWithOptions(ctx, m, ScrapeOptions{})
}

func (s *ScraperService) EnrichOneWithOptions(ctx context.Context, m *model.Media, options ScrapeOptions) error {
	lib, err := s.repo.Library.FindByID(ctx, m.LibraryID)
	if err != nil {
		return err
	}

	seriesLike := mediaIsEpisodic(m, lib)
	cloudMedia := isCloudMediaPath(m.Path) || (lib != nil && isCloudMediaPath(lib.Path))
	var local *LocalMetadata
	if !cloudMedia {
		if found, err := ReadLocalMetadata(m.Path, lib.Path, seriesLike); err == nil && found != nil {
			local = found
		} else if err != nil {
			s.log.Warn("read local metadata before scrape failed", zap.String("media_id", m.ID), zap.Error(err))
		}
	}
	if hinted, _ := pathHintMetadata(m.Path, seriesLike); hinted != nil {
		local = mergeScrapePathHintMetadata(local, hinted)
	}
	if local != nil {
		applyLocalMetadata(m, local)
	}

	year := mediaYearHint(m)

	if s.adult != nil && s.adult.Enabled() {
		if code := firstText(localAdultCode(local), AdultCodeFromMediaPath(m.Path), normalizeAdultCode(m.OriginalName), normalizeAdultCode(m.Title)); code != "" {
			if adultMatch, err := s.adult.Search(ctx, code); err == nil && adultMatch != nil {
				mergeLocalMetadataIntoMatch(adultMatch, local)
				return s.applyProviderMatchWithOptions(ctx, m, lib, adultMatch, options)
			} else if err != nil {
				s.log.Debug("adult metadata search failed", zap.String("media_id", m.ID), zap.String("code", code), zap.Error(err))
			}
		}
	}

	if match := s.matchFromMediaExternalIDs(ctx, m, lib); match != nil {
		s.applyFanartArtwork(ctx, match)
		mergeLocalMetadataIntoMatch(match, local)
		return s.applyProviderMatchWithOptions(ctx, m, lib, match, options)
	}

	candidates := scrapeQueryCandidates(m, lib)
	var query string
	match := (*Match)(nil)
	for _, candidate := range candidates {
		query = candidate
		candidateMatch := s.lookup(ctx, lib, m, candidate, year)
		if candidateMatch == nil {
			continue
		}
		if !organizeMetadataMatchTrusted(candidate, year, candidateMatch) {
			s.log.Warn("metadata scrape match rejected",
				zap.String("media_id", m.ID),
				zap.String("query", candidate),
				zap.String("title", candidateMatch.Title),
				zap.Int("source_year", year),
				zap.Int("match_year", candidateMatch.Year),
				zap.Int("tmdb_id", candidateMatch.TMDbID),
				zap.Int("bangumi_id", candidateMatch.BangumiID),
				zap.String("douban_id", candidateMatch.DoubanID),
				zap.String("thetvdb_id", candidateMatch.TheTVDBID))
			continue
		}
		preferLocalizedSearchTitle(candidate, candidateMatch)
		match = candidateMatch
		if match != nil {
			break
		}
	}
	if match == nil {
		if local != nil && !local.PathHint {
			return s.applyLocalMetadataMatch(ctx, m, local)
		}
		_ = s.repo.DB.Model(&model.Media{}).Where("id = ?", m.ID).
			Update("scrape_status", "no_match").Error
		s.invalidateMediaCache(ctx)
		s.log.Info("metadata scrape no match",
			zap.String("media_id", m.ID),
			zap.String("query", query),
			zap.String("library_type", lib.Type))
		return nil
	}
	s.applyFanartArtwork(ctx, match)
	mergeLocalMetadataIntoMatch(match, local)

	return s.applyProviderMatchWithOptions(ctx, m, lib, match, options)
}

func (s *ScraperService) applyProviderMatch(ctx context.Context, m *model.Media, lib *model.Library, match *Match) error {
	return s.applyProviderMatchWithOptions(ctx, m, lib, match, ScrapeOptions{})
}

func (s *ScraperService) applyProviderMatchWithOptions(ctx context.Context, m *model.Media, lib *model.Library, match *Match, options ScrapeOptions) error {
	posterCandidate := match.PosterURL
	backdropCandidate := match.BackdropURL
	posterURL, removePoster := s.prepareScrapedArtworkURL(ctx, m.ID, "poster_url", m.PosterURL, posterCandidate)
	backdropURL, removeBackdrop := s.prepareScrapedArtworkURL(ctx, m.ID, "backdrop_url", m.BackdropURL, backdropCandidate)
	updates := map[string]any{
		"title":         match.Title,
		"overview":      match.Overview,
		"poster_url":    posterURL,
		"backdrop_url":  backdropURL,
		"rating":        match.Rating,
		"year":          match.Year,
		"scrape_status": "matched",
	}
	if match.OriginalName != "" {
		updates["original_name"] = match.OriginalName
	}
	if strings.TrimSpace(m.EpisodeTitle) != "" {
		updates["episode_title"] = strings.TrimSpace(m.EpisodeTitle)
	}
	if match.TMDbID > 0 {
		updates["tm_db_id"] = match.TMDbID
	}
	if match.BangumiID > 0 {
		updates["bangumi_id"] = match.BangumiID
	}
	if match.DoubanID != "" {
		updates["douban_id"] = match.DoubanID
	}
	if match.TheTVDBID != "" {
		updates["thetvdb_id"] = match.TheTVDBID
	}
	if match.NSFW {
		updates["nsfw"] = true
	}
	if len(match.Genres) > 0 {
		updates["genres"] = strings.Join(match.Genres, ",")
	}
	if len(match.Countries) > 0 {
		updates["countries"] = strings.Join(match.Countries, ",")
	}
	if len(match.Languages) > 0 {
		updates["languages"] = strings.Join(match.Languages, ",")
	}
	applyScrapeMediaTypeResets(updates, match)

	if err := s.repo.DB.Model(&model.Media{}).Where("id = ?", m.ID).
		Updates(updates).Error; err != nil {
		return err
	}
	s.removeCachedScrapedArtwork(removePoster, removeBackdrop)

	// Fetch extended metadata after the selected match is already saved.
	// Manual cloud/batch applies must not fail just because an optional provider
	// details request is slow or unavailable.
	if match.TMDbID > 0 && s.tmdb != nil && s.tmdb.Enabled() {
		mediaType := s.determineMediaTypeForMedia(lib, m, match)
		s.fetchAndSaveTMDbExtendedMetadata(ctx, m.ID, match.TMDbID, mediaType)
		if mediaType == "tv" && !options.DeferEpisodeDetails {
			s.fetchAndSaveTMDbEpisodeDetails(ctx, m, match.TMDbID, match.Year, options)
		}
	}
	if !(options.DeferEpisodeDetails && m != nil && m.EpisodeNum > 0) {
		s.writeMediaNFOAfterScrape(ctx, m, lib)
	}
	s.invalidateMediaCache(ctx)
	s.hub.Publish("scrape", map[string]any{
		"media_id":   m.ID,
		"title":      match.Title,
		"tmdb_id":    match.TMDbID,
		"bangumi_id": match.BangumiID,
		"douban_id":  match.DoubanID,
		"thetvdb_id": match.TheTVDBID,
		"source":     map[bool]string{true: "adult"}[match.NSFW],
	})
	return nil
}

func applyScrapeMediaTypeResets(updates map[string]any, match *Match) {
	if updates == nil || match == nil {
		return
	}
	switch normalizeOrganizeMediaType(match.MediaType) {
	case "movie", "adult":
		updates["season_num"] = 0
		updates["episode_num"] = 0
		updates["episode_title"] = ""
		updates["series_id"] = ""
		if match.TMDbID <= 0 {
			updates["tm_db_id"] = 0
		}
		if match.BangumiID <= 0 {
			updates["bangumi_id"] = 0
		}
		if strings.TrimSpace(match.DoubanID) == "" {
			updates["douban_id"] = ""
		}
		if strings.TrimSpace(match.TheTVDBID) == "" {
			updates["thetvdb_id"] = ""
		}
	}
}