feat(verification): add user identity verification system

Implement a complete user identity verification system with support for multiple identity types (student, teacher, staff, alumni). The system includes user-facing verification submission and status checking endpoints, admin endpoints for reviewing verification requests, middleware for protecting verification-required routes, and integration with the user model to track verification status.

internal/service/verification_service.go

@@ -0,0 +1,176 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	apperrors "carrot_bbs/internal/errors"
+	"carrot_bbs/internal/model"
+	"carrot_bbs/internal/repository"
+)
+
+type VerificationService interface {
+	SubmitVerification(ctx context.Context, userID string, identity model.UserIdentity, realName, studentID, employeeID, department, proofMaterials string) (*model.VerificationRecord, error)
+	GetVerificationStatus(ctx context.Context, userID string) (*VerificationStatusResponse, error)
+	GetVerificationRecords(ctx context.Context, userID string, page, pageSize int) ([]*model.VerificationRecord, int64, error)
+}
+
+type VerificationStatusResponse struct {
+	UserID             string                    `json:"user_id"`
+	Identity           string                    `json:"identity"`
+	VerificationStatus string                    `json:"verification_status"`
+	HasPendingRequest  bool                      `json:"has_pending_request"`
+	LatestRecord       *model.VerificationRecord `json:"latest_record,omitempty"`
+}
+
+type verificationServiceImpl struct {
+	verificationRepo repository.VerificationRepository
+	userRepo         repository.UserRepository
+}
+
+func NewVerificationService(
+	verificationRepo repository.VerificationRepository,
+	userRepo repository.UserRepository,
+) VerificationService {
+	return &verificationServiceImpl{
+		verificationRepo: verificationRepo,
+		userRepo:         userRepo,
+	}
+}
+
+func (s *verificationServiceImpl) SubmitVerification(ctx context.Context, userID string, identity model.UserIdentity, realName, studentID, employeeID, department, proofMaterials string) (*model.VerificationRecord, error) {
+	user, err := s.userRepo.GetByID(userID)
+	if err != nil {
+		return nil, apperrors.ErrUserNotFound
+	}
+
+	if user.VerificationStatus == model.VerificationStatusApproved {
+		return nil, apperrors.ErrAlreadyVerified
+	}
+
+	existing, err := s.verificationRepo.GetPendingByUserID(userID)
+	if err == nil && existing != nil {
+		return nil, apperrors.ErrVerificationPending
+	}
+
+	record := &model.VerificationRecord{
+		UserID:         userID,
+		Identity:       identity,
+		Status:         model.VerificationStatusPending,
+		RealName:       realName,
+		StudentID:      studentID,
+		EmployeeID:     employeeID,
+		Department:     department,
+		ProofMaterials: proofMaterials,
+	}
+
+	if err := s.verificationRepo.Create(record); err != nil {
+		return nil, fmt.Errorf("创建认证记录失败: %w", err)
+	}
+
+	user.VerificationStatus = model.VerificationStatusPending
+	user.Identity = identity
+	if err := s.userRepo.Update(user); err != nil {
+		return nil, fmt.Errorf("更新用户状态失败: %w", err)
+	}
+
+	return record, nil
+}
+
+func (s *verificationServiceImpl) GetVerificationStatus(ctx context.Context, userID string) (*VerificationStatusResponse, error) {
+	user, err := s.userRepo.GetByID(userID)
+	if err != nil {
+		return nil, apperrors.ErrUserNotFound
+	}
+
+	response := &VerificationStatusResponse{
+		UserID:             userID,
+		Identity:           string(user.Identity),
+		VerificationStatus: string(user.VerificationStatus),
+		HasPendingRequest:  false,
+	}
+
+	latestRecord, err := s.verificationRepo.GetLatestByUserID(userID)
+	if err == nil && latestRecord != nil {
+		response.LatestRecord = latestRecord
+		response.HasPendingRequest = latestRecord.Status == model.VerificationStatusPending
+	}
+
+	return response, nil
+}
+
+func (s *verificationServiceImpl) GetVerificationRecords(ctx context.Context, userID string, page, pageSize int) ([]*model.VerificationRecord, int64, error) {
+	return s.verificationRepo.GetRecordsByUserID(userID, page, pageSize)
+}
+
+type AdminVerificationService interface {
+	ListVerifications(ctx context.Context, page, pageSize int, status, keyword string) ([]*model.VerificationRecord, int64, error)
+	GetVerificationDetail(ctx context.Context, id string) (*model.VerificationRecord, error)
+	ReviewVerification(ctx context.Context, reviewerID string, recordID string, approve bool, rejectReason string) (*model.VerificationRecord, error)
+}
+
+type adminVerificationServiceImpl struct {
+	verificationRepo repository.VerificationRepository
+	userRepo         repository.UserRepository
+}
+
+func NewAdminVerificationService(
+	verificationRepo repository.VerificationRepository,
+	userRepo repository.UserRepository,
+) AdminVerificationService {
+	return &adminVerificationServiceImpl{
+		verificationRepo: verificationRepo,
+		userRepo:         userRepo,
+	}
+}
+
+func (s *adminVerificationServiceImpl) ListVerifications(ctx context.Context, page, pageSize int, status, keyword string) ([]*model.VerificationRecord, int64, error) {
+	return s.verificationRepo.List(page, pageSize, status, keyword)
+}
+
+func (s *adminVerificationServiceImpl) GetVerificationDetail(ctx context.Context, id string) (*model.VerificationRecord, error) {
+	return s.verificationRepo.GetByID(id)
+}
+
+func (s *adminVerificationServiceImpl) ReviewVerification(ctx context.Context, reviewerID string, recordID string, approve bool, rejectReason string) (*model.VerificationRecord, error) {
+	record, err := s.verificationRepo.GetByID(recordID)
+	if err != nil {
+		return nil, apperrors.ErrVerificationNotFound
+	}
+
+	if record.Status != model.VerificationStatusPending {
+		return nil, apperrors.ErrVerificationAlreadyHandled
+	}
+
+	if approve {
+		record.Status = model.VerificationStatusApproved
+	} else {
+		record.Status = model.VerificationStatusRejected
+		record.RejectReason = rejectReason
+	}
+
+	now := time.Now()
+	record.ReviewedBy = &reviewerID
+	record.ReviewedAt = &now
+
+	if err := s.verificationRepo.Update(record); err != nil {
+		return nil, fmt.Errorf("更新认证记录失败: %w", err)
+	}
+
+	user, err := s.userRepo.GetByID(record.UserID)
+	if err != nil {
+		return record, nil
+	}
+
+	if approve {
+		user.VerificationStatus = model.VerificationStatusApproved
+		user.Identity = record.Identity
+	} else {
+		user.VerificationStatus = model.VerificationStatusRejected
+	}
+
+	_ = s.userRepo.Update(user)
+
+	return record, nil
+}