# Model #

class User(db.Model):
    __tablename__ = 'users'
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(32), index=True)
    password_hash = db.Column(db.String(64))

    # User email information
    email = db.Column(db.String(255), nullable=False, unique=True)

    # User information
    first_name = db.Column(db.String(50), nullable=False, default='')
    last_name = db.Column(db.String(50), nullable=False, default='')

    # User Profile
    user_type = db.Column(db.String(50), nullable=False, default='')

    # verify if account enabled
    is_enabled = db.Column(db.Boolean(), nullable=False, default=False)

    def is_active(self):
        return self.is_enabled

    def hash_password(self, password):
        self.password_hash = pwd_context.encrypt(password)

    def verify_password(self, password):
        return pwd_context.verify(password, self.password_hash)

    def generate_auth_token(self, expiration=600):
        s = Serializer(app.config['SECRET_KEY'], expires_in=expiration)
        return s.dumps({'id': self.id})

    @staticmethod
    def verify_auth_token(token):
        s = Serializer(app.config['SECRET_KEY'])
        try:
            data = s.loads(token)
        except SignatureExpired:
            return None    # valid token, but expired
        except BadSignature:
            return None    # invalid token
        user = User.query.get(data['id'])
        return user


# Schemas #


class RegistrationSchema(Schema):
    not_blank = validate.Length(min=1, error='Field cannot be blank')
    id = fields.Integer(dump_only=True)
    email = fields.Email(required=True, validate=not_blank)
    username = fields.String(required=True, validate=not_blank)
    password = fields.String(load_only=True, required=True, validate=not_blank)
    first_name = fields.String(required=True, validate=not_blank)
    last_name = fields.String(required=True, validate=not_blank)
    user_type = fields.String(required=True, validate=not_blank)
    is_enabled = fields.Boolean()

    class Meta:
        type_ = 'user'
        self_url = '/api/users/{id}'
        self_url_kwargs = {'id': '<id>'}
        strict = True

def J(*args, **kwargs):
    """Wrapper around jsonify that sets the Content-Type of the response to
    application/vnd.api+json.
    """
    response = jsonify(*args, **kwargs)
    response.mimetype = 'application/vnd.api+json'
    return response

@app.route('/api/users', methods=['POST'])
def new_user():
    schema = RegistrationSchema()
    input_data = request.get_json() or {}
    data, errs = schema.load(input_data)
    if errs:
        return J(errs), 422
    db.session.add(data)
    db.session.commit()
    return J(data)