package repository

import (
	"carrotskin/internal/model"
	"context"

	"gorm.io/gorm"
)

// textureRepository TextureRepository的实现
type textureRepository struct {
	db *gorm.DB
}

// NewTextureRepository 创建TextureRepository实例
func NewTextureRepository(db *gorm.DB) TextureRepository {
	return &textureRepository{db: db}
}

func (r *textureRepository) Create(ctx context.Context, texture *model.Texture) error {
	return r.db.WithContext(ctx).Create(texture).Error
}

func (r *textureRepository) FindByID(ctx context.Context, id int64) (*model.Texture, error) {
	var texture model.Texture
	err := r.db.WithContext(ctx).Preload("Uploader").First(&texture, id).Error
	return handleNotFoundResult(&texture, err)
}

func (r *textureRepository) FindByHash(ctx context.Context, hash string) (*model.Texture, error) {
	var texture model.Texture
	err := r.db.WithContext(ctx).Where("hash = ?", hash).First(&texture).Error
	return handleNotFoundResult(&texture, err)
}

func (r *textureRepository) FindByIDs(ctx context.Context, ids []int64) ([]*model.Texture, error) {
	if len(ids) == 0 {
		return []*model.Texture{}, nil
	}
	var textures []*model.Texture
	// 使用 IN 查询优化批量查询，并预加载关联
	err := r.db.WithContext(ctx).Where("id IN ?", ids).
		Preload("Uploader").
		Find(&textures).Error
	return textures, err
}

func (r *textureRepository) FindByUploaderID(ctx context.Context, uploaderID int64, page, pageSize int) ([]*model.Texture, int64, error) {
	var textures []*model.Texture
	var total int64

	query := r.db.WithContext(ctx).Model(&model.Texture{}).Where("uploader_id = ? AND status != -1", uploaderID)

	if err := query.Count(&total).Error; err != nil {
		return nil, 0, err
	}

	err := query.Scopes(Paginate(page, pageSize)).
		Preload("Uploader").
		Order("created_at DESC").
		Find(&textures).Error

	if err != nil {
		return nil, 0, err
	}

	return textures, total, nil
}

func (r *textureRepository) Search(ctx context.Context, keyword string, textureType model.TextureType, publicOnly bool, page, pageSize int) ([]*model.Texture, int64, error) {
	var textures []*model.Texture
	var total int64

	query := r.db.WithContext(ctx).Model(&model.Texture{}).Where("status = 1")

	if publicOnly {
		query = query.Where("is_public = ?", true)
	}
	if textureType != "" {
		query = query.Where("type = ?", textureType)
	}
	if keyword != "" {
		query = query.Where("name LIKE ? OR description LIKE ?", "%"+keyword+"%", "%"+keyword+"%")
	}

	if err := query.Count(&total).Error; err != nil {
		return nil, 0, err
	}

	err := query.Scopes(Paginate(page, pageSize)).
		Preload("Uploader").
		Order("created_at DESC").
		Find(&textures).Error

	if err != nil {
		return nil, 0, err
	}

	return textures, total, nil
}

func (r *textureRepository) Update(ctx context.Context, texture *model.Texture) error {
	return r.db.WithContext(ctx).Save(texture).Error
}

func (r *textureRepository) UpdateFields(ctx context.Context, id int64, fields map[string]interface{}) error {
	return r.db.WithContext(ctx).Model(&model.Texture{}).Where("id = ?", id).Updates(fields).Error
}

func (r *textureRepository) Delete(ctx context.Context, id int64) error {
	return r.db.WithContext(ctx).Model(&model.Texture{}).Where("id = ?", id).Update("status", -1).Error
}

func (r *textureRepository) BatchUpdate(ctx context.Context, ids []int64, fields map[string]interface{}) (int64, error) {
	if len(ids) == 0 {
		return 0, nil
	}
	result := r.db.WithContext(ctx).Model(&model.Texture{}).Where("id IN ?", ids).Updates(fields)
	return result.RowsAffected, result.Error
}

func (r *textureRepository) BatchDelete(ctx context.Context, ids []int64) (int64, error) {
	if len(ids) == 0 {
		return 0, nil
	}
	result := r.db.WithContext(ctx).Model(&model.Texture{}).Where("id IN ?", ids).Update("status", -1)
	return result.RowsAffected, result.Error
}

func (r *textureRepository) IncrementDownloadCount(ctx context.Context, id int64) error {
	return r.db.WithContext(ctx).Model(&model.Texture{}).Where("id = ?", id).
		UpdateColumn("download_count", gorm.Expr("download_count + ?", 1)).Error
}

func (r *textureRepository) IncrementFavoriteCount(ctx context.Context, id int64) error {
	return r.db.WithContext(ctx).Model(&model.Texture{}).Where("id = ?", id).
		UpdateColumn("favorite_count", gorm.Expr("favorite_count + ?", 1)).Error
}

func (r *textureRepository) DecrementFavoriteCount(ctx context.Context, id int64) error {
	return r.db.WithContext(ctx).Model(&model.Texture{}).Where("id = ?", id).
		UpdateColumn("favorite_count", gorm.Expr("favorite_count - ?", 1)).Error
}

func (r *textureRepository) CreateDownloadLog(ctx context.Context, log *model.TextureDownloadLog) error {
	return r.db.WithContext(ctx).Create(log).Error
}

func (r *textureRepository) IsFavorited(ctx context.Context, userID, textureID int64) (bool, error) {
	var count int64
	// 使用 Select("1") 优化，只查询是否存在，不需要查询所有字段
	err := r.db.WithContext(ctx).Model(&model.UserTextureFavorite{}).
		Select("1").
		Where("user_id = ? AND texture_id = ?", userID, textureID).
		Limit(1).
		Count(&count).Error
	return count > 0, err
}

func (r *textureRepository) AddFavorite(ctx context.Context, userID, textureID int64) error {
	favorite := &model.UserTextureFavorite{
		UserID:    userID,
		TextureID: textureID,
	}
	return r.db.WithContext(ctx).Create(favorite).Error
}

func (r *textureRepository) RemoveFavorite(ctx context.Context, userID, textureID int64) error {
	return r.db.WithContext(ctx).Where("user_id = ? AND texture_id = ?", userID, textureID).
		Delete(&model.UserTextureFavorite{}).Error
}

func (r *textureRepository) GetUserFavorites(ctx context.Context, userID int64, page, pageSize int) ([]*model.Texture, int64, error) {
	var textures []*model.Texture
	var total int64

	subQuery := r.db.WithContext(ctx).Model(&model.UserTextureFavorite{}).
		Select("texture_id").
		Where("user_id = ?", userID)

	query := r.db.WithContext(ctx).Model(&model.Texture{}).
		Where("id IN (?) AND status = 1", subQuery)

	if err := query.Count(&total).Error; err != nil {
		return nil, 0, err
	}

	err := query.Scopes(Paginate(page, pageSize)).
		Preload("Uploader").
		Order("created_at DESC").
		Find(&textures).Error

	if err != nil {
		return nil, 0, err
	}

	return textures, total, nil
}

func (r *textureRepository) CountByUploaderID(ctx context.Context, uploaderID int64) (int64, error) {
	var count int64
	err := r.db.WithContext(ctx).Model(&model.Texture{}).
		Where("uploader_id = ? AND status != -1", uploaderID).
		Count(&count).Error
	return count, err
}