package repository

import (
	"errors"

	appErrors "github.com/topfans/backend/pkg/errors"
	"github.com/topfans/backend/pkg/models"
	"gorm.io/gorm"
)

// CollectionRepository 典藏藏品Repository接口
type CollectionRepository interface {
	// Create 创建典藏藏品
	Create(asset *models.CollectionAsset) error

	// GetByID 根据ID查询
	GetByID(id int64) (*models.CollectionAsset, error)

	// GetByAssetID 根据asset_id查询
	GetByAssetID(assetID int64) (*models.CollectionAsset, error)

	// GetByAssetIDs 批量查询
	GetByAssetIDs(assetIDs []int64) ([]*models.CollectionAsset, error)

	// GetByOwner 查询用户的典藏藏品列表
	GetByOwner(ownerUID, starID int64, limit, offset int) ([]*models.CollectionAsset, error)

	// GetByOwnerAndCategory 查询用户指定分类的典藏藏品
	GetByOwnerAndCategory(ownerUID, starID int64, category string, limit, offset int) ([]*models.CollectionAsset, error)

	// CountByOwner 统计用户的典藏藏品数量
	CountByOwner(ownerUID, starID int64) (int64, error)

	// CountByOwnerAndCategory 统计用户指定分类的典藏藏品数量
	CountByOwnerAndCategory(ownerUID, starID int64, category string) (int64, error)

	// UpdateLikeCount 更新点赞数
	UpdateLikeCount(id int64, likeCount int32) error

	// IncrementLikeCount 增加点赞数
	IncrementLikeCount(id int64) error

	// DecrementLikeCount 减少点赞数
	DecrementLikeCount(id int64) error
}

// collectionRepository 典藏藏品Repository实现
type collectionRepository struct {
	db *gorm.DB
}

// NewCollectionRepository 创建典藏藏品Repository实例
func NewCollectionRepository(db *gorm.DB) CollectionRepository {
	return &collectionRepository{db: db}
}

// Create 创建典藏藏品
func (r *collectionRepository) Create(asset *models.CollectionAsset) error {
	if asset == nil {
		return errors.New("collection asset cannot be nil")
	}
	if asset.OwnerUID <= 0 {
		return errors.New("owner_uid must be greater than 0")
	}
	if asset.StarID <= 0 {
		return errors.New("star_id must be greater than 0")
	}
	return r.db.Create(asset).Error
}

// GetByID 根据ID查询
func (r *collectionRepository) GetByID(id int64) (*models.CollectionAsset, error) {
	if id <= 0 {
		return nil, errors.New("id must be greater than 0")
	}
	var asset models.CollectionAsset
	if err := r.db.Where("id = ?", id).First(&asset).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, appErrors.ErrCollectionAssetNotFound
		}
		return nil, err
	}
	return &asset, nil
}

// GetByAssetID 根据asset_id查询
func (r *collectionRepository) GetByAssetID(assetID int64) (*models.CollectionAsset, error) {
	if assetID <= 0 {
		return nil, errors.New("asset_id must be greater than 0")
	}
	var asset models.CollectionAsset
	if err := r.db.Where("asset_id = ?", assetID).First(&asset).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, appErrors.ErrCollectionAssetNotFound
		}
		return nil, err
	}
return &asset, nil
}

// GetByAssetIDs 批量查询
func (r *collectionRepository) GetByAssetIDs(assetIDs []int64) ([]*models.CollectionAsset, error) {
	if len(assetIDs) == 0 {
		return []*models.CollectionAsset{}, nil
	}
	var assets []*models.CollectionAsset
	if err := r.db.Where("asset_id IN ?", assetIDs).Find(&assets).Error; err != nil {
		return nil, err
	}
	return assets, nil
}

// GetByOwner 查询用户的典藏藏品列表
func (r *collectionRepository) GetByOwner(ownerUID, starID int64, limit, offset int) ([]*models.CollectionAsset, error) {
	if ownerUID <= 0 {
		return nil, errors.New("owner_uid must be greater than 0")
	}
	if starID <= 0 {
		return nil, errors.New("star_id must be greater than 0")
	}
	var assets []*models.CollectionAsset
	query := r.db.Where("owner_uid = ? AND star_id = ?", ownerUID, starID).
		Order("created_at DESC")
	if limit > 0 {
		query = query.Limit(limit)
	}
	if offset > 0 {
		query = query.Offset(offset)
	}
	if err := query.Find(&assets).Error; err != nil {
		return nil, err
	}
	return assets, nil
}

// GetByOwnerAndCategory 查询用户指定分类的典藏藏品
func (r *collectionRepository) GetByOwnerAndCategory(ownerUID, starID int64, category string, limit, offset int) ([]*models.CollectionAsset, error) {
	if ownerUID <= 0 {
		return nil, errors.New("owner_uid must be greater than 0")
	}
	if starID <= 0 {
		return nil, errors.New("star_id must be greater than 0")
	}
	var assets []*models.CollectionAsset
	query := r.db.Where("owner_uid = ? AND star_id = ? AND category = ?", ownerUID, starID, category).
		Order("created_at DESC")
	if limit > 0 {
		query = query.Limit(limit)
	}
	if offset > 0 {
		query = query.Offset(offset)
	}
	if err := query.Find(&assets).Error; err != nil {
		return nil, err
	}
	return assets, nil
}

// CountByOwner 统计用户的典藏藏品数量
func (r *collectionRepository) CountByOwner(ownerUID, starID int64) (int64, error) {
	if ownerUID <= 0 {
		return 0, errors.New("owner_uid must be greater than 0")
	}
	if starID <= 0 {
		return 0, errors.New("star_id must be greater than 0")
	}
	var count int64
	if err := r.db.Model(&models.CollectionAsset{}).
		Where("owner_uid = ? AND star_id = ?", ownerUID, starID).
		Count(&count).Error; err != nil {
		return 0, err
	}
	return count, nil
}

// CountByOwnerAndCategory 统计用户指定分类的典藏藏品数量
func (r *collectionRepository) CountByOwnerAndCategory(ownerUID, starID int64, category string) (int64, error) {
	if ownerUID <= 0 {
		return 0, errors.New("owner_uid must be greater than 0")
	}
	if starID <= 0 {
		return 0, errors.New("star_id must be greater than 0")
	}
	var count int64
	if err := r.db.Model(&models.CollectionAsset{}).
		Where("owner_uid = ? AND star_id = ? AND category = ?", ownerUID, starID, category).
		Count(&count).Error; err != nil {
		return 0, err
	}
	return count, nil
}

// UpdateLikeCount 更新点赞数
func (r *collectionRepository) UpdateLikeCount(id int64, likeCount int32) error {
	if id <= 0 {
		return errors.New("id must be greater than 0")
	}
	return r.db.Model(&models.CollectionAsset{}).
		Where("id = ?", id).
		Update("like_count", likeCount).Error
}

// IncrementLikeCount 增加点赞数
func (r *collectionRepository) IncrementLikeCount(id int64) error {
	if id <= 0 {
		return errors.New("id must be greater than 0")
	}
	return r.db.Model(&models.CollectionAsset{}).
		Where("id = ?", id).
		UpdateColumn("like_count", gorm.Expr("like_count + ?", 1)).Error
}

// DecrementLikeCount 减少点赞数
func (r *collectionRepository) DecrementLikeCount(id int64) error {
	if id <= 0 {
		return errors.New("id must be greater than 0")
	}
	return r.db.Model(&models.CollectionAsset{}).
		Where("id = ? AND like_count > ?", id, 0).
		UpdateColumn("like_count", gorm.Expr("like_count - ?", 1)).Error
}