package sequence

import (
	"context"
	"fmt"
	"time"

	"pay-bridge/internal/model"
	"pay-bridge/internal/repository"
)

// Service 订单编码服务
type Service struct {
	repo *repository.SequenceRepository
}

func NewService(repo *repository.SequenceRepository) *Service {
	return &Service{repo: repo}
}

// NextTradeNo 生成下一个交易号，格式：PAY{yyMMdd}{8位序号}
func (s *Service) NextTradeNo(ctx context.Context, appID string) (string, error) {
	return s.next(ctx, appID, model.SeqTypeTrade)
}

// NextRefundNo 生成下一个退款单号，格式：REF{yyMMdd}{8位序号}
func (s *Service) NextRefundNo(ctx context.Context, appID string) (string, error) {
	return s.next(ctx, appID, model.SeqTypeRefund)
}

// NextSharingNo 生成下一个分润单号，格式：SHA{yyMMdd}{8位序号}
func (s *Service) NextSharingNo(ctx context.Context, appID string) (string, error) {
	return s.next(ctx, appID, model.SeqTypeSharing)
}

func (s *Service) next(ctx context.Context, appID string, seqType model.SeqType) (string, error) {
	val, err := s.repo.IncrAndGet(ctx, appID, seqType)
	if err != nil {
		return "", err
	}

	prefix, err := s.repo.GetPrefix(ctx, appID, seqType)
	if err != nil {
		return "", err
	}

	date := time.Now().Format("060102") // yyMMdd
	seq := fmt.Sprintf("%08d", val%100_000_000) // 8 位，溢出归零（每日最多1亿笔）
	return prefix + date + seq, nil
}