新增订单群聊

backend/internal/modules/chat/service.go

@@ -0,0 +1,70 @@
+package chat
+
+import (
+	"errors"
+	"strings"
+)
+
+var (
+	ErrDependencyUnavailable = errors.New("dependency unavailable")
+	ErrConversationNotFound  = errors.New("conversation not found")
+	ErrPermissionDenied      = errors.New("permission denied")
+	ErrInvalidMessage        = errors.New("invalid message")
+)
+
+type Service struct {
+	repo *Repository
+}
+
+func NewService(repo *Repository) *Service {
+	return &Service{repo: repo}
+}
+
+func (s *Service) ListConversations(principal Principal, page, pageSize int) (*PaginatedResult, error) {
+	if s.repo == nil {
+		return nil, ErrDependencyUnavailable
+	}
+	return s.repo.ListConversations(principal, page, pageSize)
+}
+
+func (s *Service) FindConversation(principal Principal, id uint64) (*ConversationDTO, error) {
+	if s.repo == nil {
+		return nil, ErrDependencyUnavailable
+	}
+	return s.repo.FindConversation(principal, id)
+}
+
+func (s *Service) FindOrderConversation(userID uint64, orderID uint64) (*ConversationDTO, error) {
+	if s.repo == nil {
+		return nil, ErrDependencyUnavailable
+	}
+	return s.repo.FindOrderConversation(userID, orderID)
+}
+
+func (s *Service) Messages(principal Principal, conversationID uint64, page, pageSize int) (*PaginatedResult, error) {
+	if s.repo == nil {
+		return nil, ErrDependencyUnavailable
+	}
+	return s.repo.Messages(principal, conversationID, page, pageSize)
+}
+
+func (s *Service) SendMessage(principal Principal, conversationID uint64, req SendMessageRequest) (*MessageDTO, error) {
+	if s.repo == nil {
+		return nil, ErrDependencyUnavailable
+	}
+	req.Content = strings.TrimSpace(req.Content)
+	if conversationID == 0 || req.Content == "" {
+		return nil, ErrInvalidMessage
+	}
+	if len([]rune(req.Content)) > 1000 {
+		return nil, ErrInvalidMessage
+	}
+	return s.repo.SendMessage(principal, conversationID, req)
+}
+
+func (s *Service) MarkRead(principal Principal, conversationID uint64) error {
+	if s.repo == nil {
+		return ErrDependencyUnavailable
+	}
+	return s.repo.MarkRead(principal, conversationID)
+}