"""User API blueprint and endpoint definitions."""
from flask import Blueprint, abort, request, g

from atheneum.api.decorators import return_json
from atheneum.api.model import APIResponse
from atheneum.middleware import authentication_middleware
from atheneum.model import User
from atheneum.service import (
    patch_service,
    transformation_service,
    user_service
)
from atheneum.service.patch_service import get_patch_fields
from atheneum.service.role_service import Role

USER_BLUEPRINT = Blueprint(
    name='user', import_name=__name__, url_prefix='/user')


@USER_BLUEPRINT.route('/<name>', methods=['GET'])
@return_json
@authentication_middleware.require_token_auth
@authentication_middleware.require_role(required_role=Role.USER)
def get_user(name: str) -> APIResponse:
    """
    Get a user.

    :return: user if exists, else 404
    """
    user = user_service.find_by_name(name)
    if user is not None:
        return APIResponse(user, 200)
    return abort(404)


@USER_BLUEPRINT.route('/<name>', methods=['PATCH'])
@return_json
@authentication_middleware.require_token_auth
@authentication_middleware.require_role(required_role=Role.USER)
def patch_user(name: str) -> APIResponse:
    """
    Patch a user.

    :return: user if patched, 4xx error on patching issue, 404 on nonexistent
    """
    user = user_service.find_by_name(name)
    if user is not None:
        user_patch: User = transformation_service.deserialize_model(
            User, request.json)
        try:
            patched_user = patch_service.patch(
                g.user, user, user_patch, get_patch_fields(request.json))
            return APIResponse(patched_user, 200)
        except ValueError:
            return abort(400)
    return abort(404)


@USER_BLUEPRINT.route('/', methods=['POST'])
@return_json
@authentication_middleware.require_token_auth
@authentication_middleware.require_role(required_role=Role.ADMIN)
def register_user() -> APIResponse:
    """
    Register a user with the service.

    :return: The newly registered User
    """
    new_user: User = transformation_service.deserialize_model(
        User, request.json)
    registered_user = user_service.register(
        name=new_user.name,
        password=None,
        role=new_user.role
    )
    return APIResponse(payload=registered_user, status=200)