package user

import (
	"context"
	"time"

	"bindbox-game/internal/repository/mysql/model"
)

func (s *service) ListCoupons(ctx context.Context, userID int64, page, pageSize int) (items []*model.UserCoupons, total int64, err error) {
	return s.ListCouponsByStatus(ctx, userID, 1, page, pageSize)
}

// ListCouponsByStatus 按状态获取用户优惠券列表
func (s *service) ListCouponsByStatus(ctx context.Context, userID int64, status int32, page, pageSize int) (items []*model.UserCoupons, total int64, err error) {
	q := s.readDB.UserCoupons.WithContext(ctx).ReadDB().Where(
		s.readDB.UserCoupons.UserID.Eq(userID),
		s.readDB.UserCoupons.Status.Eq(status),
	)
	total, err = q.Count()
	if err != nil {
		return nil, 0, err
	}
	if page <= 0 {
		page = 1
	}
	if pageSize <= 0 {
		pageSize = 20
	}
	if pageSize > 100 {
		pageSize = 100
	}
	items, err = q.Order(s.readDB.UserCoupons.ID.Desc()).Offset((page - 1) * pageSize).Limit(pageSize).Find()
	if err != nil {
		return nil, 0, err
	}
	return items, total, nil
}

// ListAppCoupons APP端查看优惠券
// status=1 有效（未使用+使用中）  status=2 已失效（用完+已使用+已过期）
func (s *service) ListAppCoupons(ctx context.Context, userID int64, status int32, page, pageSize int) (items []*model.UserCoupons, total int64, err error) {
	u := s.readDB.UserCoupons
	c := s.readDB.SystemCoupons
	now := time.Now()

	tableName := u.TableName()
	sysTableName := c.TableName()
	db := u.UnderlyingDB().WithContext(ctx).
		Table(tableName).
		Select("`"+tableName+"`.*").
		Joins("LEFT JOIN `"+sysTableName+"` ON `"+sysTableName+"`.id = `"+tableName+"`.coupon_id").
		Where("`"+tableName+"`.user_id = ?", userID)

	switch status {
	case 1: // 有效：余额 > 0 且 未过期
		db = db.Where(tableName+".balance_amount > ? AND "+tableName+".valid_end > ? AND "+tableName+".status IN (?, ?, ?)", 0, now, 1, 2, 4)
	case 2: // 已失效：余额用完 OR 已标记过期 OR 已过截止时间
		db = db.Where("("+tableName+".balance_amount = ?) OR "+tableName+".status = ? OR "+tableName+".valid_end <= ?", 0, 3, now)
	default:
		db = db.Where(tableName+".balance_amount > ? AND "+tableName+".valid_end > ? AND "+tableName+".status IN (?, ?, ?)", 0, now, 1, 2, 4)
	}

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

	if page <= 0 {
		page = 1
	}
	if pageSize <= 0 {
		pageSize = 20
	}

	err = db.Order("`" + tableName + "`.id DESC").Offset((page - 1) * pageSize).Limit(pageSize).Scan(&items).Error
	if err != nil {
		return nil, 0, err
	}

	return items, total, nil
}