move: 后端

backend/internal/feed/repo.go

@@ -0,0 +1,70 @@
+package feed
+
+import (
+	"context"
+	"feedsystem_video_go/internal/social"
+	"feedsystem_video_go/internal/video"
+	"time"
+
+	"gorm.io/gorm"
+)
+
+type FeedRepository struct {
+	db *gorm.DB
+}
+
+func NewFeedRepository(db *gorm.DB) *FeedRepository {
+	return &FeedRepository{db: db}
+}
+
+func (repo *FeedRepository) ListLatest(ctx context.Context, limit int, latestBefore time.Time) ([]*video.Video, error) {
+	var videos []*video.Video
+	query := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Order("create_time DESC")
+	if !latestBefore.IsZero() {
+		query = query.Where("create_time < ?", latestBefore)
+	}
+	if err := query.Limit(limit).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}
+
+func (repo *FeedRepository) ListLikesCountWithCursor(ctx context.Context, limit int, cursor *LikesCountCursor) ([]*video.Video, error) {
+	var videos []*video.Video
+	query := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Order("likes_count DESC, id DESC")
+
+	if cursor != nil {
+		query = query.Where(
+			"(likes_count < ?) OR (likes_count = ? AND id < ?)",
+			cursor.LikesCount,
+			cursor.LikesCount, cursor.ID,
+		)
+	}
+
+	if err := query.Limit(limit).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}
+
+func (repo *FeedRepository) ListByFollowing(ctx context.Context, limit int, viewerAccountID uint, latestBefore time.Time) ([]*video.Video, error) {
+	var videos []*video.Video
+	query := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Order("create_time DESC")
+	if viewerAccountID > 0 {
+		followingSubQuery := repo.db.WithContext(ctx).
+			Model(&social.Social{}).
+			Select("vlogger_id").
+			Where("follower_id = ?", viewerAccountID)
+		query = query.Where("author_id IN (?)", followingSubQuery)
+	}
+	if !latestBefore.IsZero() {
+		query = query.Where("create_time < ?", latestBefore)
+	}
+	if err := query.Limit(limit).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}