chore: import clean Agent Desk snapshot (3/7)

internal/services/ticket_no_service.go

@@ -0,0 +1,123 @@
+package services
+
+import (
+	"agent-desk/internal/models"
+	"agent-desk/internal/repositories"
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/mlogclub/simple/sqls"
+	"gorm.io/gorm"
+)
+
+var TicketNoSequenceService = newTicketNoSequenceService()
+
+func newTicketNoSequenceService() *ticketNoSequenceService {
+	return &ticketNoSequenceService{}
+}
+
+type ticketNoSequenceService struct {
+	ticketNoSQLiteMu sync.Mutex
+}
+
+func (s *ticketNoSequenceService) Next(now time.Time) (string, error) {
+	s.ticketNoSQLiteMu.Lock()
+	defer s.ticketNoSQLiteMu.Unlock()
+
+	return s.nextWithRetry(sqls.DB(), now)
+}
+
+func (s *ticketNoSequenceService) nextWithRetry(tx *gorm.DB, now time.Time) (string, error) {
+	dateKey := now.Format("20060102")
+	for attempt := 0; attempt < 100; attempt++ {
+		current, err := repositories.TicketNoSequenceRepository.GetByDateKeyForUpdate(tx, dateKey)
+		if err != nil {
+			if isRetriableTicketNoError(tx, err) {
+				sleepTicketNoRetry(attempt)
+				continue
+			}
+			return "", err
+		}
+		if current == nil {
+			item := &models.TicketNoSequence{
+				DateKey:   dateKey,
+				NextSeq:   2,
+				CreatedAt: now,
+				UpdatedAt: now,
+			}
+			err := repositories.TicketNoSequenceRepository.Create(tx, item)
+			if err == nil {
+				return formatTicketNo(dateKey, 1), nil
+			}
+			if !isRetriableTicketNoError(tx, err) {
+				return "", err
+			}
+
+			current, err = repositories.TicketNoSequenceRepository.GetByDateKeyForUpdate(tx, dateKey)
+			if err != nil {
+				if isRetriableTicketNoError(tx, err) {
+					sleepTicketNoRetry(attempt)
+					continue
+				}
+				return "", err
+			}
+			if current == nil {
+				sleepTicketNoRetry(attempt)
+				continue
+			}
+		}
+		allocated := current.NextSeq
+		ok, err := repositories.TicketNoSequenceRepository.UpdateNextSeq(tx, current.ID, allocated, allocated+1, now)
+		if err != nil {
+			if isRetriableTicketNoError(tx, err) {
+				sleepTicketNoRetry(attempt)
+				continue
+			}
+			return "", err
+		}
+		if ok {
+			return formatTicketNo(dateKey, allocated), nil
+		}
+		sleepTicketNoRetry(attempt)
+	}
+	return "", fmt.Errorf("failed to allocate ticket number")
+}
+
+func sleepTicketNoRetry(attempt int) {
+	delay := time.Duration(attempt+1) * 10 * time.Millisecond
+	if delay > 200*time.Millisecond {
+		delay = 200 * time.Millisecond
+	}
+	time.Sleep(delay)
+}
+
+func formatTicketNo(dateKey string, seq int64) string {
+	return fmt.Sprintf("TK%s%05d", dateKey, seq)
+}
+
+func isDuplicateKeyError(err error) bool {
+	if err == nil {
+		return false
+	}
+	message := strings.ToLower(err.Error())
+	return strings.Contains(message, "duplicate") || strings.Contains(message, "unique") || strings.Contains(message, "constraint failed")
+}
+
+func isRetriableTicketNoError(tx *gorm.DB, err error) bool {
+	if isDuplicateKeyError(err) {
+		return true
+	}
+	return tx != nil && tx.Dialector.Name() == "sqlite" && isSQLiteDatabaseLockedError(err)
+}
+
+func isSQLiteDatabaseLockedError(err error) bool {
+	if err == nil {
+		return false
+	}
+	message := strings.ToLower(err.Error())
+	return strings.Contains(message, "database is locked") ||
+		strings.Contains(message, "database table is locked") ||
+		strings.Contains(message, "database is busy")
+}