package repository

import (
	"database/sql"

	"gpt-manager-go/internal/models"

	"github.com/lib/pq"
)

// CardKeyRepository 卡密仓储
type CardKeyRepository struct {
	db *sql.DB
}

// NewCardKeyRepository 创建仓储
func NewCardKeyRepository(db *sql.DB) *CardKeyRepository {
	return &CardKeyRepository{db: db}
}

// FindByKey 根据卡密查找
func (r *CardKeyRepository) FindByKey(key string) (*models.CardKey, error) {
	cardKey := &models.CardKey{}
	err := r.db.QueryRow(`
		SELECT id, key, max_uses, used_count, validity_type, expires_at, is_active, created_by_id, created_at
		FROM card_keys WHERE key = $1
	`, key).Scan(
		&cardKey.ID, &cardKey.Key, &cardKey.MaxUses, &cardKey.UsedCount,
		&cardKey.ValidityType, &cardKey.ExpiresAt, &cardKey.IsActive,
		&cardKey.CreatedByID, &cardKey.CreatedAt,
	)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	return cardKey, err
}

// IncrementUsedCount 增加使用次数，如果达到最大次数则设为不活跃
func (r *CardKeyRepository) IncrementUsedCount(id int) error {
	_, err := r.db.Exec(`
		UPDATE card_keys 
		SET used_count = used_count + 1,
		    is_active = CASE WHEN used_count + 1 >= max_uses THEN false ELSE is_active END
		WHERE id = $1
	`, id)
	return err
}

// Create 创建卡密
func (r *CardKeyRepository) Create(cardKey *models.CardKey) error {
	return r.db.QueryRow(`
		INSERT INTO card_keys (key, max_uses, used_count, validity_type, expires_at, is_active, created_by_id, created_at)
		VALUES ($1, $2, $3, $4, $5, $6, $7, $8)
		RETURNING id
	`,
		cardKey.Key,
		cardKey.MaxUses,
		cardKey.UsedCount,
		cardKey.ValidityType,
		cardKey.ExpiresAt,
		cardKey.IsActive,
		cardKey.CreatedByID,
		cardKey.CreatedAt,
	).Scan(&cardKey.ID)
}

// FindAll 获取所有卡密
func (r *CardKeyRepository) FindAll() ([]*models.CardKey, error) {
	rows, err := r.db.Query(`
		SELECT id, key, max_uses, used_count, validity_type, expires_at, is_active, created_by_id, created_at
		FROM card_keys ORDER BY created_at DESC
	`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var cardKeys []*models.CardKey
	for rows.Next() {
		ck := &models.CardKey{}
		if err := rows.Scan(
			&ck.ID, &ck.Key, &ck.MaxUses, &ck.UsedCount,
			&ck.ValidityType, &ck.ExpiresAt, &ck.IsActive,
			&ck.CreatedByID, &ck.CreatedAt,
		); err != nil {
			return nil, err
		}
		cardKeys = append(cardKeys, ck)
	}
	return cardKeys, nil
}

// FindAllPaginated 分页获取卡密
func (r *CardKeyRepository) FindAllPaginated(page, pageSize int) ([]*models.CardKey, error) {
	offset := (page - 1) * pageSize
	rows, err := r.db.Query(`
		SELECT id, key, max_uses, used_count, validity_type, expires_at, is_active, created_by_id, created_at
		FROM card_keys ORDER BY created_at DESC
		LIMIT $1 OFFSET $2
	`, pageSize, offset)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var cardKeys []*models.CardKey
	for rows.Next() {
		ck := &models.CardKey{}
		if err := rows.Scan(
			&ck.ID, &ck.Key, &ck.MaxUses, &ck.UsedCount,
			&ck.ValidityType, &ck.ExpiresAt, &ck.IsActive,
			&ck.CreatedByID, &ck.CreatedAt,
		); err != nil {
			return nil, err
		}
		cardKeys = append(cardKeys, ck)
	}
	return cardKeys, nil
}

// Count 获取卡密总数
func (r *CardKeyRepository) Count() (int, error) {
	var count int
	err := r.db.QueryRow(`SELECT COUNT(*) FROM card_keys`).Scan(&count)
	return count, err
}

// Delete 删除单个卡密
func (r *CardKeyRepository) Delete(id int) error {
	_, err := r.db.Exec(`DELETE FROM card_keys WHERE id = $1`, id)
	return err
}

// BatchDelete 批量删除卡密
func (r *CardKeyRepository) BatchDelete(ids []int) error {
	if len(ids) == 0 {
		return nil
	}
	// 构建 IN 子句
	query := `DELETE FROM card_keys WHERE id = ANY($1)`
	_, err := r.db.Exec(query, pq.Array(ids))
	return err
}

// ToggleActive 切换卡密激活状态
func (r *CardKeyRepository) ToggleActive(id int, isActive bool) error {
	_, err := r.db.Exec(`UPDATE card_keys SET is_active = $1 WHERE id = $2`, isActive, id)
	return err
}