# author:duoduo3369@gmail.com  https://github.com/duoduo369
"""
Weixin OAuth2 backend
"""
from urllib.parse import urlencode

from requests import HTTPError

from ..exceptions import AuthCanceled, AuthUnknownError
from .oauth import BaseOAuth2


class WeixinOAuth2(BaseOAuth2):
    """Weixin OAuth authentication backend"""

    name = "weixin"
    ID_KEY = "openid"
    AUTHORIZATION_URL = "https://open.weixin.qq.com/connect/qrconnect"
    ACCESS_TOKEN_URL = "https://api.weixin.qq.com/sns/oauth2/access_token"
    ACCESS_TOKEN_METHOD = "POST"
    DEFAULT_SCOPE = ["snsapi_login"]
    REDIRECT_STATE = False
    EXTRA_DATA = [
        ("nickname", "username"),
        ("headimgurl", "profile_image_url"),
    ]

    def get_user_details(self, response):
        """Return user details from Weixin. API URL is:
        https://api.weixin.qq.com/sns/userinfo
        """
        if self.setting("DOMAIN_AS_USERNAME"):
            username = response.get("domain", "")
        else:
            username = response.get("nickname", "")
        return {
            "username": username,
            "profile_image_url": response.get("headimgurl", ""),
        }

    def user_data(self, access_token, *args, **kwargs):
        data = self.get_json(
            "https://api.weixin.qq.com/sns/userinfo",
            params={
                "access_token": access_token,
                "openid": kwargs["response"]["openid"],
            },
        )
        nickname = data.get("nickname")
        if nickname:
            # weixin api has some encode bug, here need handle
            data["nickname"] = nickname.encode("raw_unicode_escape").decode("utf-8")
        return data

    def auth_params(self, state=None):
        appid, secret = self.get_key_and_secret()
        params = {"appid": appid, "redirect_uri": self.get_redirect_uri(state)}
        if self.STATE_PARAMETER and state:
            params["state"] = state
        if self.RESPONSE_TYPE:
            params["response_type"] = self.RESPONSE_TYPE
        return params

    def auth_complete_params(self, state=None):
        appid, secret = self.get_key_and_secret()
        return {
            "grant_type": "authorization_code",  # request auth code
            "code": self.data.get("code", ""),  # server response code
            "appid": appid,
            "secret": secret,
            "redirect_uri": self.get_redirect_uri(state),
        }

    def refresh_token_params(self, token, *args, **kwargs):
        appid, secret = self.get_key_and_secret()
        return {
            "refresh_token": token,
            "grant_type": "refresh_token",
            "appid": appid,
            "secret": secret,
        }

    def auth_complete(self, *args, **kwargs):
        """Completes login process, must return user instance"""
        self.process_error(self.data)
        try:
            response = self.request_access_token(
                self.ACCESS_TOKEN_URL,
                data=self.auth_complete_params(self.validate_state()),
                headers=self.auth_headers(),
                method=self.ACCESS_TOKEN_METHOD,
            )
        except HTTPError as err:
            if err.response.status_code == 400:
                raise AuthCanceled(self, response=err.response)
            else:
                raise
        except KeyError:
            raise AuthUnknownError(self)
        if "errcode" in response:
            raise AuthCanceled(self)
        self.process_error(response)
        return self.do_auth(
            response["access_token"], response=response, *args, **kwargs
        )


class WeixinOAuth2APP(WeixinOAuth2):
    """
    Weixin OAuth authentication backend

    Can't use in web, only in weixin app
    """

    name = "weixinapp"
    ID_KEY = "openid"
    AUTHORIZATION_URL = "https://open.weixin.qq.com/connect/oauth2/authorize"
    ACCESS_TOKEN_URL = "https://api.weixin.qq.com/sns/oauth2/access_token"
    ACCESS_TOKEN_METHOD = "POST"
    REDIRECT_STATE = False

    def auth_url(self):
        if self.STATE_PARAMETER or self.REDIRECT_STATE:
            # Store state in session for further request validation. The state
            # value is passed as state parameter (as specified in OAuth2 spec),
            # but also added to redirect, that way we can still verify the
            # request if the provider doesn't implement the state parameter.
            # Reuse token if any.
            name = self.name + "_state"
            state = self.strategy.session_get(name)
            if state is None:
                state = self.state_token()
                self.strategy.session_set(name, state)
        else:
            state = None

        params = self.auth_params(state)
        params.update(self.get_scope_argument())
        params.update(self.auth_extra_arguments())
        params = urlencode(sorted(params.items()))
        return "{}#wechat_redirect".format(self.AUTHORIZATION_URL + "?" + params)

    def auth_complete_params(self, state=None):
        appid, secret = self.get_key_and_secret()
        return {
            "grant_type": "authorization_code",  # request auth code
            "code": self.data.get("code", ""),  # server response code
            "appid": appid,
            "secret": secret,
        }

    def validate_state(self):
        return None

    def auth_complete(self, *args, **kwargs):
        """Completes login process, must return user instance"""
        self.process_error(self.data)
        try:
            response = self.request_access_token(
                self.ACCESS_TOKEN_URL,
                data=self.auth_complete_params(self.validate_state()),
                headers=self.auth_headers(),
                method=self.ACCESS_TOKEN_METHOD,
            )
        except HTTPError as err:
            if err.response.status_code == 400:
                raise AuthCanceled(self)
            else:
                raise
        except KeyError:
            raise AuthUnknownError(self)

        if "errcode" in response:
            raise AuthCanceled(self)
        self.process_error(response)
        return self.do_auth(
            response["access_token"], response=response, *args, **kwargs
        )