ch17

internal/models/users.go

@@ -22,6 +22,8 @@ type UserModelInterface interface {
 	Insert(name, email, password string) error
 	Authenticate(email, password string) (int, error)
 	Exists(id int) (bool, error)
+	GetById(id int) (*User, error)
+	ChangePassword(id int, curr_pass, new_pass string) error
 }
 
 type UserModel struct {
@@ -82,3 +84,46 @@ func (m *UserModel) Exists(id int) (bool, error) {
 	err := m.DB.QueryRow(stmt, id).Scan(&exists)
 	return exists, err
 }
+
+func (a *UserModel) GetById(id int) (*User, error) {
+	acc := User{}
+
+	stmt := `SELECT name, email, created FROM users WHERE id = ?`
+	err := a.DB.QueryRow(stmt, id).Scan(&acc.Name, &acc.Email, &acc.Created)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return nil, ErrInvalidCredentials
+		}
+		return nil, err
+	}
+
+	return &acc, nil
+}
+
+func (a *UserModel) ChangePassword(id int, curr_pass, new_pass string) error {
+	hashedNewPassword, err := bcrypt.GenerateFromPassword([]byte(new_pass), 12)
+	if err != nil {
+		return err
+	}
+
+	var hashedDBPassword []byte
+	stmt := `SELECT hashed_password FROM users WHERE id = ?`
+	err = a.DB.QueryRow(stmt, id).Scan(&hashedDBPassword)
+	if err != nil {
+		return err
+	}
+	err = bcrypt.CompareHashAndPassword(hashedDBPassword, []byte(curr_pass))
+	if err != nil {
+		if errors.Is(err, bcrypt.ErrMismatchedHashAndPassword) {
+			return ErrInvalidCredentials
+		}
+		return err
+	}
+
+	stmt = `UPDATE users SET hashed_password = ? WHERE id = ?`
+	_, err = a.DB.Exec(stmt, hashedNewPassword, id)
+	if err != nil {
+		return err
+	}
+	return nil
+}