"""

    AUTHOR:

        Khushal P Soonderji

    DATE:

        Wednesday, 30th Oct., 2024.

    OBJECTIVE:

        To provide a data model for describing the tokens to be used for Google's APIs.

    REFERENCES:

        N/A

    DOWNLOADS:

        N/A

"""


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# To make sibling directories accessible for imports:
import sys
sys.path.append(".")
sys.path.append("..")

# For making data behaviour_models:
from pydantic import BaseModel, Field, field_validator, model_validator, AwareDatetime
from typing import Optional, Literal, Union, Dict, List, Any

# Related to Google:
from google.auth.transport.requests import Request
from google.oauth2.credentials import Credentials

# My utils:
from utils_v2.string import json
from utils_v2.string import regex
from utils_v2.date_time import date_time

# To work with date and time:
import datetime
import dateparser

# To make API calls:
import httpx


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# --- Nothing Yet


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class GoogleAuthTokens(BaseModel):

    accessToken: str = Field(description = "the main 'bearer' token")
    refreshToken: str = Field(description = "token to be used to refresh the access token")
    expiresAt: AwareDatetime = Field(description = "the time (utc) at which the token will expire")
    scopes: List[str] = Field(description = "the list of permissions", default = [])
    email: str | None = Field(description = "the email id of the user", default = None)

    # ┏┓    ┏•
    # ┃ ┏┓┏┓╋┓┏┓
    # ┗┛┗┛┛┗┛┗┗┫
    #          ┛

    class Config:
        extra = "allow"

    # ┓┏  ┓• ┓   •
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    # ┗┛┗┻┗┗┗┻┗┻┗┗┗┛┛┗

    @field_validator("expiresAt", mode = "before")
    def parse_dates(cls, value):
        if not isinstance(value, datetime.datetime):
            parsed = date_time.parse_date_time(value, date_formats = ["%Y%m%d", "%Y-%m-%d"])
            value = parsed if isinstance(parsed, datetime.datetime) else dateparser.parse(value)
        if isinstance(value, datetime.datetime): value = date_time.to_timezone(value, date_time.TIMEZONE_UTC)
        return value

    # ┏┓           •
    # ┃┃┏┓┏┓┏┓┏┓┏┓╋┓┏┓┏
    # ┣┛┛ ┗┛┣┛┗ ┛ ┗┗┗ ┛
    #       ┛

    @property
    def expired(self):
        return True if date_time.get_current_utc_date_time() >= self.expiresAt else False

    @property
    def ttl(self):
        return (self.expiresAt - date_time.get_current_utc_date_time()).total_seconds()

    # ┏┓           ┏┓
    # ┃ ┓┏┏╋┏┓┏┳┓  ┣ ┓┏┏┓┏┏
    # ┗┛┗┻┛┗┗┛┛┗┗  ┻ ┗┻┛┗┗┛

    def refresh(
            self,
            client_id: str,
            client_secret: str,
            force_refresh: bool = False
    ) -> bool:

        """
        Synchronously (blocking) refreshes the existing access tokens in place.
        :param client_id: The id of the client (OAuth JSON) for which these tokens were granted.
        :param client_secret: The secret of the client (OAuth JSON) for which these tokens were granted.
        :param force_refresh: Whether you want to refresh the token even if it hasn't expired.
        :return: True if refreshed, else False.
        """

        # Start by assuming failure:
        success = False

        try:

            # Go ahead only if either the token has expired,
            # or the user has asked to forcefully refresh the tokens:
            if self.expired or force_refresh:

                # Create the credentials:
                credentials = Credentials.from_authorized_user_info(
                    info = {
                        "client_id": client_id,
                        "client_secret": client_secret,
                        "refresh_token": self.refreshToken,
                        "expires_at": self.expiresAt
                    }
                )

                # Request a refresh:
                credentials.refresh(Request())

                # Note down the new credentials:
                if credentials.token != self.accessToken:
                    success = True
                    self.accessToken = credentials.token
                    self.refreshToken = credentials.refresh_token
                    self.expiresAt = date_time.as_if_timezone(credentials.expiry, timezone = date_time.TIMEZONE_UTC)

        # In case something goes wrong:
        except Exception as exception:
            success = False

        # Done here:
        return success

    async def arefresh(
            self,
            http_client: httpx.AsyncClient,
            client_id: str,
            client_secret: str,
            force_refresh: bool = False
    ) -> bool:

        """
        Asynchronously refreshes the existing access tokens in place.
        :param http_client: The HTTP client to use to make the refresh request.
        :param client_id: The id of the client (OAuth JSON) for which these tokens were granted.
        :param client_secret: The secret of the client (OAuth JSON) for which these tokens were granted.
        :param force_refresh: Whether you want to refresh the token even if it hasn't expired.
        :return: True if refreshed, else False.
        """

        # Currently we don't really know how to refresh tokens through low-level API calls,
        # so we will pass on the intent to the regular, synchronous function.
        return self.refresh(
            client_id = client_id,
            client_secret = client_secret,
            force_refresh = force_refresh
        )

    def has_scopes(self, scopes: List[str]) -> bool:

        """
        Checks if all the specified scopes were granted.
        :param scopes: The list of scopes to check. These are the permissions you need.
        :return: True if all specified scoped are present, else False.
        """

        # Start by assuming success:
        has_scopes = True

        # Now loop through the needed scopes and check:
        for scope in scopes:
            if scope not in self.scopes:
                has_scopes = False
                break

        # Done here:
        return has_scopes


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if __name__ == "__main__":

    pass