refac: password and code hashing & checking go through a domain hasher interface used by the use cases instead of bcrypt in the user repository and the auth handler

internal/infrastructure/useCases/AuthenticateUser.go

@@ -0,0 +1,28 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/hash"
+	"RenewCMS/internal/domain/user"
+)
+
+type AuthenticateUserUseCase struct {
+	userRepository user.Repository
+	hasher         hash.Hasher
+}
+
+func NewAuthenticateUserUseCase(userRepository user.Repository, hasher hash.Hasher) *AuthenticateUserUseCase {
+	return &AuthenticateUserUseCase{userRepository, hasher}
+}
+
+func (a *AuthenticateUserUseCase) Authenticate(username string, password string) (user.User, error) {
+	dbUser, err := a.userRepository.GetByUsername(username)
+	if err != nil {
+		return user.User{}, err
+	}
+
+	if err := a.hasher.Compare(dbUser.Password, password); err != nil {
+		return user.User{}, user.ErrInvalidCredentials
+	}
+
+	return dbUser, nil
+}