pluto/handler/transactions.py

# Twisted/Klein imports
from twisted.logger import Logger

# Other library imports
from json import dumps
from random import choices
from string import ascii_uppercase

# Project imports
from settings import settings
from db import r
from util import convert


class Transactions(object):
    """
    Handler class for incoming Revolut transactions.
    """

    def __init__(self):
        """
        Initialise the Transaction object.
        Set the logger.
        """
        self.log = Logger("transactions")

    def set_agora(self, agora):
        self.agora = agora

    def set_irc(self, irc):
        self.irc = irc

    def transaction(self, data):
        """
        Store details of transaction and post notifications to IRC.
        Matches it up with data stored in Redis to attempt to reconcile with an Agora trade.
        :param data: details of transaction
        :type data: dict
        """
        event = data["event"]
        ts = data["timestamp"]

        inside = data["data"]
        txid = inside["id"]
        txtype = inside["type"]
        state = inside["state"]
        if "reference" in inside:
            reference = inside["reference"]
        else:
            reference = "not_given"

        leg = inside["legs"][0]

        if "counterparty" in leg:
            account_type = leg["counterparty"]["account_type"]
        else:
            account_type = "not_given"

        amount = leg["amount"]
        currency = leg["currency"]
        description = leg["description"]

        to_store = {
            "event": event,
            "ts": ts,
            "txid": txid,
            "txtype": txtype,
            "state": state,
            "reference": reference,
            "account_type": account_type,
            "amount": amount,
            "currency": currency,
            "description": description,
        }

        self.log.info("Transaction processed: {formatted}", formatted=dumps(to_store, indent=2))
        r.hmset(f"tx.{txid}", to_store)
        self.irc.client.msg(
            self.irc.client.channel, f"AUTO Incoming transaction: {amount}{currency} ({reference}) - {state} - {description}"
        )
        stored_trade = r.hgetall(f"trade.{reference}")
        if not stored_trade:
            self.log.info(f"No reference in DB for {reference}")
            return
        stored_trade = convert(stored_trade)
        amount = float(amount)
        stored_trade["amount"] = float(stored_trade["amount"])
        if not stored_trade["currency"] == currency:
            self.irc.client.msg(self.irc.client.channel, f"Currency mismatch, Agora: {stored_trade['currency']} / Revolut: {currency}")
            return
        if not stored_trade["amount"] == amount:
            # If the amount does not match exactly, get the min and max values for our given acceptable margins for trades
            min_amount, max_amount = self.agora.get_acceptable_margins(currency, amount)
            self.irc.client.msg(
                self.irc.client.channel, f"Amount does not match exactly, trying with margins: min: {min_amount} / max: {max_amount}"
            )
            if not min_amount < stored_trade["amount"] < max_amount:
                self.irc.client.msg(
                    self.irc.client.channel,
                    f"Amount mismatch - not in margins: {stored_trade['amount']} (min: {min_amount} / max: {max_amount}",
                )
                return
        if not account_type == "revolut":
            self.irc.client.msg(self.irc.client.channel, f"Account type is not Revolut: {account_type}")
            return
        self.irc.client.msg(self.irc.client.channel, f"All checks passed, would release funds for {stored_trade['id']}")

    def new_trade(self, trade_id, buyer, currency, amount, amount_xmr):
        """
        Called when we have a new trade in Agora.
        Store details in Redis, generate a reference and optionally let the customer know the reference.
        """
        reference = "".join(choices(ascii_uppercase, k=5))
        reference = f"XMR-{reference}"
        existing_ref = r.get(f"trade.{trade_id}.reference")
        if existing_ref:
            self.irc.client.msg(self.irc.client.channel, f"Existing reference for {trade_id}: {existing_ref.decode('utf-8')}")
        else:
            r.set(f"trade.{trade_id}.reference", reference)
            to_store = {
                "id": trade_id,
                "buyer": buyer,
                "currency": currency,
                "amount": amount,
                "amount_xmr": amount_xmr,
                "reference": reference,
            }
            self.log.info(f"Storing trade information: {str(to_store)}")
            r.hmset(f"trade.{reference}", to_store)
            self.irc.client.msg(self.irc.client.channel, f"Generated reference for {trade_id}: {reference}")
            if settings.Agora.Send == "1":
                self.agora.agora.contact_message_post(trade_id, f"Hi! When sending the payment please use reference code: {reference}")

    def find_tx(self, reference, amount):
        """
        Find transactions that match the given reference and amount.
        :param reference: transaction reference in Revolut
        :param amount: transaction amount
        :type reference: string
        :type amount: int
        :return: transaction details or AMOUNT_INVALID, or False
        :rtype: dict or string or bool
        """
        all_transactions = r.scan(0, match="tx.*")
        for tx_iter in all_transactions[1]:
            tx_obj = r.hgetall(tx_iter)
            if tx_obj[b"reference"] == str.encode(reference):
                if tx_obj[b"amount"] == str.encode(amount):
                    return convert(tx_obj)
                else:
                    return "AMOUNT_INVALID"
        return False

    def get_refs(self):
        """
        Get all reference IDs for trades.
        :return: list of trade IDs
        :rtype: list
        """
        references = []
        ref_keys = r.keys("trade.*.reference")
        for key in ref_keys:
            references.append(r.get(key))
        return convert(references)

    def get_ref(self, reference):
        """
        Get a reference ID for a single trade.
        :return: trade ID
        :rtype: string
        """
        ref_data = convert(r.hgetall(f"trade.{reference}"))
        if not ref_data:
            return False
        return ref_data

    def del_ref(self, reference):
        """
        Delete a given reference from the Redis database.
        """
        r.delete(f"trade.{reference}")
        r.delete(f"trade.{reference}.reference")

    def del_tx(self, txid):
        pass

    def tx_to_ref(self, tx):
        pass

    def ref_to_tx(self, reference):
        pass