package mysqldao

import (
	"context"

	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/global"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/internal/mysqlmodel"
	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

// LikeDao 点赞数据访问
type LikeDao struct {
	db *gorm.DB
}

// NewLikeDao 创建点赞 DAO
func NewLikeDao() *LikeDao {
	return &LikeDao{db: global.MysqlEngine}
}

// LikeCreate 创建点赞记录
func (d *LikeDao) LikeCreate(ctx context.Context, like *mysqlmodel.Like) error {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.LikeCreate")
	defer span.End()

	if err := d.db.WithContext(ctx).Create(like).Error; err != nil {
		span.RecordError(err)
		return err
	}
	return nil
}

// LikeUpsertOn 点赞幂等写入：唯一索引冲突时仅置 status=1，防并发重复插入。
func (d *LikeDao) LikeUpsertOn(ctx context.Context, like *mysqlmodel.Like) error {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.LikeUpsertOn")
	defer span.End()

	if err := d.db.WithContext(ctx).Clauses(clause.OnConflict{
		Columns:   []clause.Column{{Name: "like_type"}, {Name: "target_id"}, {Name: "user_id"}},
		DoUpdates: clause.AssignmentColumns([]string{"status"}),
	}).Create(like).Error; err != nil {
		span.RecordError(err)
		return err
	}
	return nil
}

// LikeUpdateStatus 更新点赞状态（1=已点赞 0=已取消）
func (d *LikeDao) LikeUpdateStatus(ctx context.Context, id int64, status int8) error {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.LikeUpdateStatus")
	defer span.End()

	if err := d.db.WithContext(ctx).Model(&mysqlmodel.Like{}).Where("id = ?", id).UpdateColumn("status", status).Error; err != nil {
		span.RecordError(err)
		return err
	}
	return nil
}

// LikeGetByTargetAndUser 查询用户在目标上的点赞记录
func (d *LikeDao) LikeGetByTargetAndUser(ctx context.Context, likeType int8, targetID, userID int64) (*mysqlmodel.Like, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.LikeGetByTargetAndUser")
	defer span.End()

	var like mysqlmodel.Like
	if err := d.db.WithContext(ctx).Where("like_type = ? AND target_id = ? AND user_id = ?", likeType, targetID, userID).First(&like).Error; err != nil {
		span.RecordError(err)
		return nil, err
	}
	return &like, nil
}

// LikeCountByTarget 统计目标点赞数（仅 status=1）
func (d *LikeDao) LikeCountByTarget(ctx context.Context, likeType int8, targetID int64) (int64, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.LikeCountByTarget")
	defer span.End()

	var count int64
	if err := d.db.WithContext(ctx).Model(&mysqlmodel.Like{}).
		Where("like_type = ? AND target_id = ? AND status = ?", likeType, targetID, int8(1)).
		Count(&count).Error; err != nil {
		span.RecordError(err)
		return 0, err
	}
	return count, nil
}

// LikeCountByTargets 批量统计多个目标的点赞数（仅 status=1），返回 targetID -> count；空入参短路。
func (d *LikeDao) LikeCountByTargets(ctx context.Context, likeType int8, targetIDs []int64) (map[int64]int64, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.LikeCountByTargets")
	defer span.End()

	counts := make(map[int64]int64, len(targetIDs))
	if len(targetIDs) == 0 {
		return counts, nil
	}

	var rows []struct {
		TargetID int64 `gorm:"column:target_id"`
		Cnt      int64 `gorm:"column:cnt"`
	}
	if err := d.db.WithContext(ctx).Model(&mysqlmodel.Like{}).
		Select("target_id, COUNT(*) AS cnt").
		Where("like_type = ? AND target_id IN ? AND status = ?", likeType, targetIDs, int8(1)).
		Group("target_id").
		Scan(&rows).Error; err != nil {
		span.RecordError(err)
		return nil, err
	}
	for _, r := range rows {
		counts[r.TargetID] = r.Cnt
	}
	return counts, nil
}

// LikeListUserIDsByTarget 查询点赞用户ID列表（仅 status=1）
func (d *LikeDao) LikeListUserIDsByTarget(ctx context.Context, likeType int8, targetID int64) ([]int64, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.LikeListUserIDsByTarget")
	defer span.End()

	var ids []int64
	if err := d.db.WithContext(ctx).Model(&mysqlmodel.Like{}).
		Where("like_type = ? AND target_id = ? AND status = ?", likeType, targetID, int8(1)).
		Pluck("user_id", &ids).Error; err != nil {
		span.RecordError(err)
		return nil, err
	}
	return ids, nil
}