"""

    AUTHOR:

        Khushal P Soonderji

    DATE:

        Thursday, 19th Dec., 2024

    OBJECTIVE:

        To handle all SMS related behaviour from one place.

    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("..")

# My async utils:
from utils_v2.date_time import date_time
from utils_v2.security.otp import HashedOTP
from utils_v2.database.async_mongo_v2 import AsyncMongo
from utils_v2.cache.async_redis_cache_v2 import AsyncRedisCache

# Controllers:
from controllers_v2.message.sms.base import SMSController

# Models:
from models.core.auth_token import CoreAuthTokenModel
from models.common.function_response import FunctionCallResponse
from models.common.otp.timed_otp import GenerateTimedOTP, VerifyTimedOTP
from models.message.sms.send import NimbusSMSIndiaMessage, SavvyBulkSMSKenyaMessage

# To work with datatypes:
from typing import List, Any

# For debugging:
from icecream import IceCreamDebugger


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# --- Nothing Yet


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class TimedOTPController:

    # ┏┓┓      ┓┏
    # ┃ ┃┏┓┏┏  ┃┃┏┓┏┓┏
    # ┗┛┗┗┻┛┛  ┗┛┗┻┛ ┛

    KEY_PREFIX = "otp_"

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

    def __init__(
            self,
            debug: bool = True,
            debug_prefix: str = "TOTP (C) | ",
            debug_only_errors: bool = True
    ):

        """
        This is a simple controller that will allow us to generate and verify timed OTPs.
        :param debug: Whether, or not, you would like to print debugging messages:
        :param debug_prefix: The prefix to print with the debugging messages.
        :param debug_only_errors: Whether you would like to print only error messages or all messages.
        :return: None.
        """

        # For debugging:
        self._printer = IceCreamDebugger(prefix = debug_prefix, includeContext = True)
        if not debug: self._printer.disable()
        self._debug_only_errors = debug_only_errors

    def enable_terminal_print(self):
        self._printer.enable()

    def disable_terminal_print(self):
        self._printer.disable()

    def debug_only_errors(self):
        self._debug_only_errors = True

    def debug_everything(self):
        self._debug_only_errors = False

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

    async def generate(
            self,
            redis_cache: AsyncRedisCache,
            inbound_data: GenerateTimedOTP
    ) -> FunctionCallResponse:

        """
        To generate one OTP and store it in cache.
        :param redis_cache: The instance of the cache client to use to hold the OTP.
        :param inbound_data: The data from which the OTP will be generated.
        :return: A structured response to describe what happened in the process.
        """

        # Start by assuming failure:
        response = FunctionCallResponse()

        # Generate the OTP:
        otp_key = self.KEY_PREFIX + redis_cache.make_key(str(inbound_data.id))
        print("GENERATE KEY:", otp_key)
        otp_client = HashedOTP(secret = HashedOTP.generate_secret())
        otp = otp_client.generate_otp(count = 0)

        # Store the OTP in Redis:
        otp_stored = await redis_cache.set(
            key = otp_key,
            value = {
                "otp": otp,
                "att": inbound_data.attempts,
                "iat": date_time.get_current_utc_date_time().timestamp(),
                "sec": inbound_data.seconds
            },
            expiry = inbound_data.seconds
        )

        # Analyze the response:
        if otp_stored:
            response.success = True
            response.message = "OTP generated successfully."
            response.data = otp
        else: response.message = "Failed to generate an OTP."

        # Done here:
        return response

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

    async def verify(
            self,
            redis_cache: AsyncRedisCache,
            inbound_data: VerifyTimedOTP
    ) -> FunctionCallResponse:

        """
        To verify if an OTP is valid, or not.
        :param redis_cache: The instance of the cache client to use to hold the OTP.
        :param inbound_data: The data from which the OTP will be verified.
        :return: A structured response to describe what happened in the process.
        """

        # Start by assuming failure:
        response = FunctionCallResponse()

        # Fetch the OTP from Redis:
        otp_key = self.KEY_PREFIX + redis_cache.make_key(str(inbound_data.id))
        print("VERIFY KEY:", otp_key)
        stored_otp = await redis_cache.get(key = otp_key)
        if not stored_otp:
            response.message = "No OTP found for this request. It may have expired."
            return response

        # Delete the record from the cache.:
        await redis_cache.delete(key = otp_key)

        # Make note of the attempts left.
        # We reduce the count by one straightaway:
        attempts_left = stored_otp["att"] - 1

        # If the stored OTP matches the claimed OTP,
        # we note down the acceptance and delete the record from the cache:
        if inbound_data.otp == stored_otp["otp"]:
            response.success = True
            response.message = "OTP verified successfully."
            return response

        # If the stored OTP and the claimed OTP don't match,
        # we reduce the attempt count and store the updated payload in cache:
        elif attempts_left > 0:
            otp_updated = await redis_cache.set(
                key = otp_key,
                value = {
                    "otp": stored_otp["otp"],
                    "att": attempts_left,
                    "iat": stored_otp["iat"],
                    "sec": stored_otp["sec"]
                },
                expiry = (stored_otp["iat"] + stored_otp["sec"]) - date_time.get_current_utc_date_time().timestamp()
            )
            if not otp_updated: attempts_left = 0

        # Done here:
        response.message = f"Invalid OTP. {attempts_left} attempts left."
        return response


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if __name__ == "__main__":

    pass