package repository

import (
	"database/sql"
	"errors"
	"fmt"

	"cmautobuy/admin/model"
)

// GetSKUMapping 读取某个蝦皮 SKU 在指定 PDD 商品下的映射。
func GetSKUMapping(q Execer, shopeeSKUID, pddGoodsID string) (*model.SKUMapping, error) {
	var m model.SKUMapping
	var mappedBy sql.NullString
	err := q.QueryRow(`
		SELECT shopee_sku_id, pdd_goods_id, pdd_option_key, pdd_options,
		       goods_id, mapped_at, mapped_by
		  FROM sku_mappings
		 WHERE shopee_sku_id = ? AND pdd_goods_id = ?`,
		shopeeSKUID, pddGoodsID).Scan(
		&m.ShopeeSKUID, &m.PddGoodsID, &m.PddOptionKey, &m.PddOptions,
		&m.GoodsID, &m.MappedAt, &mappedBy)
	if errors.Is(err, sql.ErrNoRows) {
		return nil, nil
	}
	if err != nil {
		return nil, fmt.Errorf("查询规格映射失败: %w", err)
	}
	m.MappedBy = mappedBy.String
	return &m, nil
}

// UpsertSKUMapping 保存可复用规格映射，唯一键包含当前 PDD 商品。
func UpsertSKUMapping(q Execer, m model.SKUMapping) error {
	_, err := q.Exec(`
		INSERT INTO sku_mappings
		       (shopee_sku_id, pdd_goods_id, pdd_option_key, pdd_options,
		        goods_id, mapped_at, mapped_by)
		VALUES (?, ?, ?, ?, ?, ?, ?)
		ON DUPLICATE KEY UPDATE
		       pdd_option_key = VALUES(pdd_option_key),
		       pdd_options = VALUES(pdd_options),
		       goods_id = VALUES(goods_id),
		       mapped_at = VALUES(mapped_at),
		       mapped_by = VALUES(mapped_by)`,
		m.ShopeeSKUID, m.PddGoodsID, m.PddOptionKey, m.PddOptions,
		m.GoodsID, m.MappedAt, nullableText(m.MappedBy))
	if err != nil {
		return fmt.Errorf("保存规格映射失败: %w", err)
	}
	return nil
}