"""

    AUTHOR:

        Khushal P Soonderji

    DATE:

        Saturday, 7th Dec., 2024

    OBJECTIVE:

        To make payments requests from M-PESA Express.

    REFERENCES:

        1. Simulator & Docs: https://developer.safaricom.co.ke/APIs/MpesaExpressSimulate
        2. Postman Collection: https://api.postman.com/collections/4395533-1a8f1c81-0502-4f9d-8699-d45551834b7d?access_key=PMAT-01J8R72MBSHP5CJ4J9Q46TG6G9

    DOWNLOADS:

        N/A

"""


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

# System-level activities:
import io

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

# Data models:
from utils_v2.payments.safaricom.models.auth import MPesaExpressAuthorization
from utils_v2.payments.safaricom.models.api_call import MPesaExpressApiResponse

# To make REST-ful requests:
import httpx

# To work with datatypes:
from typing import Literal

# To work with date and time:
import datetime

# Misc:
import base64

# For debugging:
from icecream import IceCreamDebugger
import inspect


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# --- Nothing Yet


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# ***                                                   CLASSES                                                     ***
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class SafaricomMPesaExpress:

    def __init__(
            self,
            auth: MPesaExpressAuthorization,
            http_client: httpx.AsyncClient = None,
            debug = True,
            debug_prefix = "M-Pesa Exp | ",
            debug_only_errors = True
    ):

        # Prepare the debugging utility:
        self.__debug_prefix = debug_prefix
        self.__printer = IceCreamDebugger(prefix = debug_prefix, includeContext = True)
        if not debug: self.__printer.disable()
        self.__debug_only_errors = debug_only_errors

        # Accept the input configuration:
        self.__auth = auth

        # Accept/create an HTTP client to work with:
        if http_client: self.__http_client = http_client
        else: self.__http_client = httpx.AsyncClient(
            limits = httpx.Limits(
                max_connections = 100,  # ............ Maximum number of connections allowed in the pool.
                max_keepalive_connections = 50,  # ... Maximum number of connections that can be kept alive.
            ),
            timeout = httpx.Timeout(
                pool = 120.0,  # .... Time to wait for a free connection from the pool.
                connect = 5.0,  # ... Time to wait for establishing a connection to the server.
                write = 10.0,  # .... Time to wait for sending data.
                read = 120.0  # ..... Time to wait for receiving data.
            )
        )

    def enable_debug(self):
        self.__printer.enable()

    def disable_debug(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 __get(
            self,
            url: str,
            headers: dict = None,
            params: dict = None
    ) -> MPesaExpressApiResponse:

        """
        To call an API using the GET method.
        :param url: The URL to call.
        :param headers: The headers to pass.
        :param params: The params to send in the query string itself.
        :return: A structured response that includes the raw response, the exception (if any), and so on.
        """

        # Prepare the structure of the response:
        api_response = MPesaExpressApiResponse(
            action = inspect.stack()[1].function,
            url = url,
            method = "GET"
        )

        try:

            # Make the API call:
            response = await self.__http_client.get(
                url = url,
                headers = headers,
                params = params
            )

            # Note down the results:
            api_response.response = response
            api_response.httpCode = response.status_code
            api_response.message = response.reason_phrase

        # If something goes wrong:
        except Exception as exception:
            api_response.exception = exception
            api_response.message = str(exception)
            self.__printer(exception, api_response.url, api_response.method, headers, params)

        # Done here:
        return api_response

    async def __post(
            self,
            url: str,
            headers: dict = None,
            json: dict = None,
            data: dict = None,
            params: dict = None,
            content: str | bytes = None,
            files: dict = None
    ) -> MPesaExpressApiResponse:

        """
        To call an API using the POST method.
        :param url: The URL to call.
        :param headers: The headers to pass.
        :param json: The params to send in the JSON body.
        :param data: The params to send in the form-data in the body.
        :param params: The params to send in the query string itself.
        :param content: The raw content to be sent in the body (typically as an octet-stream).
        :param files: Any file that you may want to send.
        :return: A structured response that includes the raw response, the exception (if any), and so on.
        """

        # Prepare the structure of the response:
        api_response = MPesaExpressApiResponse(
            action = inspect.stack()[1].function,
            url = url,
            method = "POST"
        )

        try:

            # Make the API call:
            response = await self.__http_client.post(
                url = url,
                headers = headers,
                json = json,
                data = data,
                params = params,
                content = content,
                files = files
            )

            # Note down the results:
            api_response.response = response
            api_response.httpCode = response.status_code
            api_response.message = response.reason_phrase

        # If something goes wrong:
        except Exception as exception:
            api_response.exception = exception
            api_response.message = str(exception)
            self.__printer(exception, api_response.url, api_response.method, headers, json, data)

        # Done here:
        return api_response

    # ┓┏  ┓
    # ┣┫┏┓┃┏┓┏┓┏┓┏
    # ┛┗┗ ┗┣┛┗ ┛ ┛
    #      ┛

    def generate_password(
            self,
            timestamp: str
    ) -> str:

        """
        The password is a combination of the short code, the app's passkey, and the timestamp in base64
        encoded string.
        DOCUMENTATION:
            1. https://developer.safaricom.co.ke/APIs/Authorization
        :param timestamp: The time (YYYYMMDDHHmmss) at which the request is being made.
        :return: The base-64 encoded string that has to be used as the password.
        """

        if not self.__debug_only_errors:
            self.__printer("Generating Password")

        if timestamp is None: timestamp = ""
        if self.__auth.appPasskey is None: self.__auth.appPasskey = ""
        if self.__auth.businessShortCode is None: self.__auth.businessShortCode = ""
        return base64.b64encode((self.__auth.businessShortCode + self.__auth.appPasskey + timestamp).encode()).decode()

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

    async def request_payment(
            self,
            amount: float | int,
            party_a: str,
            type: Literal["CustomerPayBillOnline", "CustomerBuyGoodsOnline"],
            reference: str,
            description: str,
            callback_url: str = None,
            payer_no: str = None,
            party_b: str = None,
    ) -> MPesaExpressApiResponse:

        """
        To request a payment from a user. When this method is called, the user's phone will immediately receive a flash
        message with the payment details and payment options. The user then gets to choose his action.
        DOCUMENTATION:
            1. https://developer.safaricom.co.ke/APIs/MpesaExpressSimulate
        :param amount: The amount in Kenyan Shillings that the user must pay.
        :param party_a: The phone no. that will make the payment. Needs to be a valid Safaricom no. of the format
            2547xxxxxxxx and must be registered with M-Pesa.
        :param type: "CustomerPayBillOnline" for PayBill nos. and "CustomerBuyGoodsOnline" for Till nos.
        :param reference: A reference id from your system (not Safaricom's system) for you to identify this transaction.
            This value will be displayed to the paying customer. Can be max. of 12 characters long.
        :param description: A description about the payment. Can be max. of 13 characters long.
        :param callback_url: The URL that will receive a webhook callback when the customer either pays or declines the
            payment request. If not provided, the callback URL from the auth details will be used.
        :param payer_no: The phone no. that shall receive the payment prompt. If not provided, the value of 'party_a'
            will be copied here.
        :param party_b: The organization that receives the funds. If not provided, the Business Short Code from the auth
            details will be used.
        :return:
        """

        # Prepare the inputs:
        request_ts = datetime.datetime.now().strftime("%Y%m%d%H%M%S")
        access_token = await self.__auth.get_access_token(http_client = self.__http_client, force_refresh = False)
        input_headers = {"Authorization": f"Bearer {access_token}"}
        input_json = {
            "BusinessShortCode": self.__auth.businessShortCode,
            "Password": self.generate_password(timestamp = request_ts),
            "Timestamp": request_ts,
            "TransactionType": type,
            "PartyA": party_a,
            "PhoneNumber": payer_no or party_a,
            "Amount": str(int(amount)),
            "PartyB": party_b or self.__auth.businessShortCode,
            "CallBackURL": callback_url or self.__auth.callbackUrl,
            "AccountReference": reference,
            "TransactionDesc": description[:13] if len(description) > 13 else description
        }

        # Make the API call:
        api_response = await self.__post(
            url = r"https://api.safaricom.co.ke/mpesa/stkpush/v1/processrequest",
            headers = input_headers,
            json = input_json
        )

        # If the call failed:
        if api_response.httpCode == 400:
            api_json = await api_response.get_json()
            api_response.message = f"{api_json['errorCode']} -> {api_json['errorMessage']}"

        # If the call failed:
        if api_response.httpCode in [200]:
            api_json = await api_response.get_json()
            success = True if str(api_json.get("ResponseCode")) == "0" else False
            api_response.message = api_json.get("ResponseDescription", "N/A")
            api_response.data = api_json
            api_response.success = success
            api_response.referenceId = str(api_json["CheckoutRequestID"])

        # Done here:
        return api_response


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if __name__ == "__main__":

    import asyncio

    m_pesa_auth = MPesaExpressAuthorization(
        consumerKey = "kFiHZ3G1vCqxkQfHgMZzPvkPd5ilsJD3",
        consumerSecret = "NIp2mp1V0cSEQ63G",
        businessShortCode = "4092041",
        appPasskey = "cf5c0f05298e63b4039c60e3fd12c2f72e1adac840d3dbd68c88a33b43dbef82",
        callbackUrl = None
    )

    my_m_pesa = SafaricomMPesaExpress(
        auth = m_pesa_auth
    )

    async def main():

        # Make the request:
        response = await my_m_pesa.request_payment(
            amount = 1.00,
            party_a = "254748877373",
            type = "CustomerPayBillOnline",
            reference = "TestTransactionTXN12345678",
            description = "Some description about the payment reason...",
            callback_url = r"https://api.thecaoffice.com/converse/test/callback",
        )

        # Show the response:
        print("SUMMARY:", response.to_markdown(), "\n\n---\n\n")
        if response.success: print("DATA:", json.to_string(response.data, default = str))
        else: print("JSON:", json.to_string(await response.get_json(), default = str))

    asyncio.run(main())
