package service

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

	"cmautobuy/admin/model"
	"cmautobuy/admin/repository"
)

const maxSybShopNameLength = 500

func ListSybAllowedShops(db *sql.DB, actor *model.User) ([]model.SybAllowedShop, error) {
	if actor == nil || !actor.IsAdmin() {
		return nil, ErrAdminRequired
	}
	return repository.ListSybAllowedShops(db)
}

func CountEnabledSybAllowedShops(db *sql.DB) (int, error) {
	names, err := repository.ListEnabledSybShopNames(db)
	return len(names), err
}

func EnsureEnabledSybAllowedShops(db *sql.DB) error {
	count, err := CountEnabledSybAllowedShops(db)
	if err != nil {
		return err
	}
	if count == 0 {
		return &validationError{field: "shop_name", message: "没有启用的顺运宝同步店铺，请先由管理员配置并启用至少一个店铺"}
	}
	return nil
}

func CreateSybAllowedShop(db *sql.DB, actor *model.User, rawName string, now time.Time) error {
	if actor == nil || !actor.IsAdmin() {
		return ErrAdminRequired
	}
	name := strings.TrimSpace(rawName)
	if name == "" {
		return &validationError{field: "shop_name", message: "店铺名称不能为空"}
	}
	if len([]rune(name)) > maxSybShopNameLength {
		return &validationError{field: "shop_name", message: "店铺名称最多 500 个字符"}
	}
	id, err := randomID("SHOP-", 16)
	if err != nil {
		return fmt.Errorf("生成店铺编号失败: %w", err)
	}
	at := now.UTC().Format(model.TimeLayout)
	err = repository.InsertSybAllowedShop(db, model.SybAllowedShop{
		ShopID: id, ShopName: name, NormalizedName: name, Enabled: true,
		CreatedByUserID: actor.UserID, CreatedAt: at, UpdatedAt: at,
	})
	if errors.Is(err, repository.ErrSybAllowedShopExists) {
		return &validationError{field: "shop_name", message: "该店铺已经在允许列表中，可直接重新启用"}
	}
	return err
}

func SetSybAllowedShopEnabled(db *sql.DB, actor *model.User, shopID string, enabled bool, now time.Time) error {
	if actor == nil || !actor.IsAdmin() {
		return ErrAdminRequired
	}
	if strings.TrimSpace(shopID) == "" {
		return &validationError{field: "shop_id", message: "店铺编号不能为空"}
	}
	found, err := repository.SetSybAllowedShopEnabled(db, shopID, enabled, now.UTC().Format(model.TimeLayout))
	if err != nil {
		return err
	}
	if !found {
		return &validationError{field: "shop_id", message: "店铺不存在，请刷新页面后重试"}
	}
	return nil
}