第 1 阶段：用户与认证, mock登陆ok

backend/internal/modules/auth/repository.go

@@ -0,0 +1,58 @@
+package auth
+
+import (
+	"errors"
+	"time"
+
+	"hfb_sys/backend/internal/model"
+
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+)
+
+type UserRepository struct {
+	db *gorm.DB
+}
+
+func NewUserRepository(db *gorm.DB) *UserRepository {
+	return &UserRepository{db: db}
+}
+
+func (r *UserRepository) FindByID(id uint64) (*model.User, error) {
+	var user model.User
+	if err := r.db.First(&user, id).Error; err != nil {
+		return nil, err
+	}
+	return &user, nil
+}
+
+func (r *UserRepository) FindOrCreateByPhone(phone string) (*model.User, error) {
+	now := time.Now()
+	user := model.User{
+		Phone:          phone,
+		Nickname:       "用户" + phone[len(phone)-4:],
+		RealnameStatus: "unverified",
+		RiskStatus:     "normal",
+		CreditScore:    100,
+		Status:         "active",
+		LastLoginAt:    &now,
+	}
+
+	err := r.db.Clauses(clause.OnConflict{
+		Columns:   []clause.Column{{Name: "phone"}},
+		DoUpdates: clause.AssignmentColumns([]string{"last_login_at", "updated_at"}),
+	}).Create(&user).Error
+	if err != nil {
+		return nil, err
+	}
+
+	var found model.User
+	if err := r.db.Where("phone = ?", phone).First(&found).Error; err != nil {
+		return nil, err
+	}
+	return &found, nil
+}
+
+func IsNotFound(err error) bool {
+	return errors.Is(err, gorm.ErrRecordNotFound)
+}