package playletser

import (
	"context"
	"strings"
	"videoweb/app/api/proto"
	"videoweb/pub/common/srvdef"
	"videoweb/pub/models/playletmod"
	"videoweb/pub/models/playletthememod"
	"videoweb/pub/models/playlettopicgroupmod"

	"go.mongodb.org/mongo-driver/bson"
)

func enabledTopicGroups(ctx context.Context) (playlettopicgroupmod.PlayletTopicGroupList, *srvdef.SrvErr) {
	return playlettopicgroupmod.FindMany(ctx, bson.M{"status": true})
}

type topicPlayletCount struct {
	Id    int64 `bson:"_id"`
	Count int64 `bson:"count"`
}

// topicGroupPage 分页查询区块下有已上架短剧的专题
func topicGroupPage(ctx context.Context, group *playlettopicgroupmod.PlayletTopicGroup, skip, limit int64) (playletthememod.PlayletThemeList, map[int64]int64, int64, *srvdef.SrvErr) {
	counts := make(map[int64]int64)
	if len(group.TopicIds) == 0 {
		return playletthememod.PlayletThemeList{}, counts, 0, nil
	}
	themes, err := playletthememod.FindManyPlayletTheme(ctx, bson.M{
		playletthememod.FN.PlayletTheme.Id:     bson.M{"$in": group.TopicIds},
		playletthememod.FN.PlayletTheme.Status: true,
	})
	if err != nil {
		return nil, nil, 0, err
	}
	byID := make(map[int64]*playletthememod.PlayletTheme, len(themes))
	for _, theme := range themes {
		if theme != nil {
			byID[theme.Id] = theme
		}
	}
	rows := make([]topicPlayletCount, 0)
	err = playletmod.AggregatePlaylet(ctx, &rows, []bson.M{
		{"$match": bson.M{playletmod.FN.Playlet.Status: playletmod.StatusUp, playletmod.FN.Playlet.ThemeIds: bson.M{"$in": group.TopicIds}}},
		{"$unwind": "$" + playletmod.FN.Playlet.ThemeIds},
		{"$match": bson.M{playletmod.FN.Playlet.ThemeIds: bson.M{"$in": group.TopicIds}}},
		{"$group": bson.M{"_id": "$" + playletmod.FN.Playlet.ThemeIds, "count": bson.M{"$sum": 1}}},
	})
	if err != nil {
		return nil, nil, 0, err
	}
	for _, row := range rows {
		counts[row.Id] = row.Count
	}
	available := make(playletthememod.PlayletThemeList, 0, len(themes))
	seen := make(map[int64]bool, len(group.TopicIds))
	for _, id := range group.TopicIds {
		if seen[id] {
			continue
		}
		seen[id] = true
		if theme := byID[id]; theme != nil && counts[id] > 0 {
			available = append(available, theme)
		}
	}
	total := int64(len(available))
	if skip >= total {
		return playletthememod.PlayletThemeList{}, counts, total, nil
	}
	end := skip + limit
	if end > total {
		end = total
	}
	return available[skip:end], counts, total, nil
}

// topicGroupPageData 组装区块当前页专题及单部短剧预览
func topicGroupPageData(ctx context.Context, group *playlettopicgroupmod.PlayletTopicGroup, skip, limit int64) (*proto.PlayletTopicGroupPageItem, *srvdef.SrvErr) {
	themes, counts, totalCount, err := topicGroupPage(ctx, group, skip, limit)
	if err != nil {
		return nil, err
	}
	page := &proto.PlayletTopicGroupPageItem{
		Id: group.Id, Name: group.Name, Desc: group.Desc, Rank: group.Rank,
		TotalCount: totalCount, List: make([]*proto.PlayletTopicPageItem, 0, len(themes)),
	}
	if len(themes) == 0 {
		return page, nil
	}
	previewByTheme := make(map[int64]playletmod.PlayletList, len(themes))
	previews := make(playletmod.PlayletList, 0, len(themes))
	for _, theme := range themes {
		filter, sort := playletTopicPagePlayletQuery(0, theme.Id)
		list, err := findHomePlaylets(ctx, filter, sort, 1)
		if err != nil {
			return nil, err
		}
		previewByTheme[theme.Id] = list
		previews = append(previews, list...)
	}
	themeNameMap, err := buildHomeThemeNameMap(ctx, previews)
	if err != nil {
		return nil, err
	}
	tagNameMap, err := buildHomeTagNameMap(ctx, previews)
	if err != nil {
		return nil, err
	}
	for _, theme := range themes {
		preview := playletsToHomeCommonData(ctx, previewByTheme[theme.Id], themeNameMap, tagNameMap)
		covers := make([]string, 0, len(preview))
		if len(preview) > 0 {
			cover := preview[0].HorizontalCover
			if cover == "" {
				cover = preview[0].Cover
			}
			if cover != "" {
				covers = append(covers, cover)
			}
		}
		page.List = append(page.List, &proto.PlayletTopicPageItem{
			Id: theme.Id, Name: theme.Name, Slug: theme.Slug,
			Desc: strings.TrimSpace(theme.SeoInfo.Description),
			Icon: withImageDomain(ctx, theme.Icon), Rank: theme.Rank,
			PlayletCount: counts[theme.Id], Covers: covers, List: preview,
			SeoInfo: buildPageSeoInfoFromValue(theme.SeoInfo, theme.Name, "", buildPlayletThemeListCanonicalURL(theme.Slug, theme.Id)),
		})
	}
	return page, nil
}