electrum/plugins/exchange_rate.py

from PyQt4.QtGui import *
from PyQt4.QtCore import *

from datetime import datetime, date
import inspect
import requests
import sys
import threading
import time
import traceback
from decimal import Decimal

from electrum.bitcoin import COIN
from electrum.plugins import BasePlugin, hook
from electrum.i18n import _
from electrum.util import print_error, ThreadJob, timestamp_to_datetime
from electrum.util import format_satoshis
from electrum_gui.qt.util import *
from electrum_gui.qt.amountedit import AmountEdit

class ExchangeBase:
    history = {}
    quotes = {}

    def get_json(self, site, get_string):
        response = requests.request('GET', 'https://' + site + get_string,
                                    headers={'User-Agent' : 'Electrum'})
        return response.json()

    def print_error(self, *msg):
        print_error("[%s]" % self.name(), *msg)

    def name(self):
        return self.__class__.__name__

    def update(self, ccy):
        self.quotes = self.get_rates(ccy)
        return self.quotes

    def history_ccys(self):
        return []

    def set_history(self, ccy, history):
        '''History is a map of "%Y-%m-%d" strings to values'''
        self.history[ccy] = history

    def get_historical_rates(self, ccy):
        result = self.history.get(ccy)
        if not result:
            self.print_error("requesting historical rates for", ccy)
            t = threading.Thread(target=self.historical_rates, args=(ccy,))
            t.setDaemon(True)
            t.start()
        return result

    def historical_rate(self, ccy, d_t):
        if d_t.date() == datetime.today().date():
            rate = self.quotes.get(ccy)
        else:
            rate = self.history.get(ccy, {}).get(d_t.strftime('%Y-%m-%d'))
        return rate

    def historical_value_str(self, ccy, satoshis, d_t):
        rate = self.historical_rate(ccy, d_t)
        if rate:
             value = round(Decimal(satoshis) / COIN * Decimal(rate), 2)
             return " ".join(["{:,.2f}".format(value), ccy])
        return _("No data")

class BitcoinAverage(ExchangeBase):
    def update(self, ccy):
        json = self.get_json('api.bitcoinaverage.com', '/ticker/global/all')
        return dict([(r, Decimal(jsonresp[r]['last']))
                     for r in json if r != 'timestamp'])

class BitcoinVenezuela(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('api.bitcoinvenezuela.com', '/')
        return dict([(r, Decimal(json['BTC'][r]))
                     for r in json['BTC']])

    def history_ccys(self):
        return ['ARS', 'EUR', 'USD', 'VEF']

    def historical_rates(self, ccy):
        return self.get_json('api.bitcoinvenezuela.com',
                             "/historical/index.php?coin=BTC")[ccy +'_BTC']

class BTCParalelo(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('btcparalelo.com', '/api/price')
        return {'VEF': Decimal(json['price'])}

class Bitcurex(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('pln.bitcurex.com', '/data/ticker.json')
        pln_price = json['last']
        return {'PLN': Decimal(pln_price)}

class Bitmarket(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('www.bitmarket.pl', '/json/BTCPLN/ticker.json')
        return {'PLN': Decimal(json['last'])}

class BitPay(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('bitpay.com', '/api/rates')
        return dict([(r['code'], Decimal(r['rate'])) for r in json])

class Blockchain(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('blockchain.info', '/ticker')
        return dict([(r, Decimal(json[r]['15m'])) for r in json])

class BTCChina(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('data.btcchina.com', '/data/ticker')
        return {'CNY': Decimal(json['ticker']['last'])}

class CaVirtEx(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('www.cavirtex.com', '/api/CAD/ticker.json')
        return {'CAD': Decimal(json['last'])}

class Coinbase(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('coinbase.com',
                             '/api/v1/currencies/exchange_rates')
        return dict([(r[7:].upper(), Decimal(json[r]))
                     for r in json if r.startswith('btc_to_')])

class CoinDesk(ExchangeBase):
    def get_rates(self, ccy):
        dicts = self.get_json('api.coindesk.com',
                              '/v1/bpi/supported-currencies.json')
        json = self.get_json('api.coindesk.com',
                             '/v1/bpi/currentprice/%s.json' % ccy)
        ccys = [d['currency'] for d in dicts]
        result = dict.fromkeys(ccys)
        result[ccy] = Decimal(json['bpi'][ccy]['rate'])
        return result

    def history_starts(self):
        return { 'USD': '2012-11-30' }

    def history_ccys(self):
        return self.history_starts().keys()

    def historical_rates(self, ccy):
        start = self.history_starts()[ccy]
        end = datetime.today().strftime('%Y-%m-%d')
        # Note ?currency and ?index don't work as documented.  Sigh.
        query = ('/v1/bpi/historical/close.json?start=%s&end=%s'
                 % (start, end))
        json = self.get_json('api.coindesk.com', query)
        self.set_history(ccy, json['bpi'])

class itBit(ExchangeBase):
    def get_rates(self, ccy):
        ccys = ['USD', 'EUR', 'SGD']
        json = self.get_json('api.itbit.com', '/v1/markets/XBT%s/ticker' % ccy)
        result = dict.fromkeys(ccys)
        result[ccy] = Decimal(json['lastPrice'])
        return result

class LocalBitcoins(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('localbitcoins.com',
                             '/bitcoinaverage/ticker-all-currencies/')
        return dict([(r, Decimal(json[r]['rates']['last'])) for r in json])

class Winkdex(ExchangeBase):
    def get_rates(self, ccy):
        json = self.get_json('winkdex.com', '/api/v0/price')
        return {'USD': Decimal(json['price'] / 100.0)}

    def history_ccys(self):
        return ['USD']

    def historical_rates(self, ccy):
        json = self.get_json('winkdex.com',
                             "/api/v0/series?start_time=1342915200")
        history = json['series'][0]['results']
        self.set_history(ccy, dict([(h['timestamp'][:10], h['price'] / 100.0)
                                    for h in history]))


class Exchanger(ThreadJob):

    def __init__(self, parent):
        self.parent = parent
        self.timeout = 0

    def get_json(self, site, get_string):
        resp = requests.request('GET', 'https://' + site + get_string,
                                headers={"User-Agent":"Electrum"})
        return resp.json()

    def update_rate(self):
        try:
            rates = self.parent.exchange.update(self.parent.fiat_unit())
        except Exception as e:
            traceback.print_exc(file=sys.stderr)
            return
        self.parent.set_currencies(rates)
        self.parent.refresh_fields()

    def run(self):
        if self.parent.parent.windows and self.timeout <= time.time():
            self.update_rate()
            self.timeout = time.time() + 150

class Plugin(BasePlugin):

    def __init__(self, parent, config, name):
        BasePlugin.__init__(self, parent, config, name)
        is_exchange = lambda obj: (inspect.isclass(obj)
                                   and issubclass(obj, ExchangeBase))
        self.exchanges = dict(inspect.getmembers(sys.modules[__name__],
                                                 is_exchange))
        self.network = None
        self.set_exchange(self.config_exchange())
        self.currencies = [self.fiat_unit()]
        self.exchanger = Exchanger(self)
        self.history = {}
        self.btc_rate = Decimal("0.0")
        self.get_historical_rates()

    def config_exchange(self):
        return self.config.get('use_exchange', 'Blockchain')

    def config_history(self):
        return self.config.get('history_rates', 'unchecked') != 'unchecked'

    def set_exchange(self, name):
        class_ = self.exchanges.get(name) or self.exchanges.values()[0]
        name = class_.__name__
        self.print_error("using exchange", name)
        if self.config_exchange() != name:
            self.config.set_key('use_exchange', name, True)
        self.exchange = class_()

    @hook
    def set_network(self, network):
        if network != self.network:
            if self.network:
                self.network.remove_job(self.exchanger)
            self.network = network
            if network:
                network.add_job(self.exchanger)

    def on_new_window(self, window):
        window.connect(window, SIGNAL("refresh_currencies()"),
                       window.update_status)
        window.fx_fields = {}
        self.add_send_edit(window)
        self.add_receive_edit(window)
        history_list = window.history_list
        cols = history_list.columnCount()
        header = history_list.headerItem()
        labels = [header.text(c) for c in range(history_list.columnCount())]
        labels.extend([_('Fiat Amount'), _('Fiat Balance')])
        history_list.setColumnCount(cols + 2)
        # For unclear reasons setting this column to ResizeToContents
        # makes e.g. label editing very slow
        history_list.setColumnWidth(cols, 120)
        history_list.setColumnWidth(cols + 1, 120)
        history_list.setHeaderLabels(labels)
        window.update_status()

    def close(self):
        BasePlugin.close(self)
        self.set_network(None)
        self.exchanger = None
        for window in self.parent.windows:
            window.send_fiat_e.hide()
            window.receive_fiat_e.hide()
            if self.config_history():
                window.history_list.setColumnCount(window.history_list.columnCount() - 2)
            window.update_status()

    def set_currencies(self, currency_options):
        self.currencies = sorted(currency_options)
        for window in self.parent.windows:
            window.emit(SIGNAL("refresh_currencies()"))
            window.emit(SIGNAL("refresh_currencies_combo()"))

    def exchange_rate(self):
        '''Returns None, or the exchange rate as a Decimal'''
        rate = self.exchange.quotes.get(self.fiat_unit())
        if rate:
            return Decimal(rate)

    @hook
    def get_fiat_balance_text(self, btc_balance, r):
        # return balance as: 1.23 USD
        r[0] = self.create_fiat_balance_text(Decimal(btc_balance) / COIN)

    def get_fiat_price_text(self, r):
        # return BTC price as: 123.45 USD
        r[0] = self.create_fiat_balance_text(1)
        quote = r[0]
        if quote:
            r[0] = "%s"%quote

    @hook
    def get_fiat_status_text(self, btc_balance, r2):
        # return status as:   (1.23 USD)    1 BTC~123.45 USD
        text = ""
        r = {}
        self.get_fiat_price_text(r)
        quote = r.get(0)
        if quote:
            price_text = "1 BTC~%s"%quote
            fiat_currency = quote[-3:]
            btc_price = self.btc_rate
            fiat_balance = Decimal(btc_price) * Decimal(btc_balance) / COIN
            balance_text = "(%.2f %s)" % (fiat_balance,fiat_currency)
            text = "  " + balance_text + "     " + price_text + " "
        r2[0] = text

    def create_fiat_balance_text(self, btc_balance):
        cur_rate = self.exchange_rate()
        if cur_rate is None:
            quote_text = ""
        else:
            quote_balance = btc_balance * Decimal(cur_rate)
            self.btc_rate = cur_rate
            quote_text = "%.2f %s" % (quote_balance, self.fiat_unit())
        return quote_text

    @hook
    def load_wallet(self, wallet, window):
        self.get_historical_rates()

    def get_historical_rates(self):
        if self.config_history():
            self.exchange.get_historical_rates(self.fiat_unit())

    def request_historical_rates(self):
        try:
            self.history = self.exchange.historical_rates(self.fiat_unit())
        except Exception:
            traceback.print_exc(file=sys.stderr)
            return
        for window in self.parent.windows:
            window.need_update.set()

    def requires_settings(self):
        return True

    @hook
    def history_tab_update(self, window, entries):
        if not self.config_history():
            return
        ccy = self.fiat_unit()
        first = window.history_list.columnCount() - 2
        for item, tx in entries:
            tx_hash, conf, value, timestamp, balance = tx
            date = timestamp_to_datetime(timestamp)
            if not date:
                date = timestmap_to_datetime(0)
            for column, amount in [(first, value), (first + 1, balance)]:
                text = self.exchange.historical_value_str(ccy, amount, date)
                item.setText(column, "%16s" % text)
                item.setFont(column, QFont(MONOSPACE_FONT))
                if amount < 0:
                    item.setForeground(column, QBrush(QColor("#BC1E1E")))

    def settings_widget(self, window):
        return EnterButton(_('Settings'), self.settings_dialog)

    def settings_dialog(self):
        d = QDialog()
        d.setWindowTitle("Settings")
        layout = QGridLayout(d)
        layout.addWidget(QLabel(_('Exchange rate API: ')), 0, 0)
        layout.addWidget(QLabel(_('Currency: ')), 1, 0)
        layout.addWidget(QLabel(_('History Rates: ')), 2, 0)
        combo = QComboBox()
        combo_ex = QComboBox()
        combo_ex.addItems(sorted(self.exchanges.keys()))
        combo_ex.setCurrentIndex(combo_ex.findText(self.config_exchange()))

        hist_checkbox = QCheckBox()
        ok_button = QPushButton(_("OK"))

        def hist_checkbox_update():
            hist_checkbox.setEnabled(self.fiat_unit() in
                                     self.exchange.history_ccys())
            hist_checkbox.setChecked(self.config_history())

        def on_change(x):
            try:
                ccy = str(self.currencies[x])
            except Exception:
                return
            if ccy != self.fiat_unit():
                self.config.set_key('currency', ccy, True)
                hist_checkbox_update()
                for window in self.parent.windows:
                    window.update_status()

        def on_change_ex(idx):
            exchange = str(combo_ex.currentText())
            if exchange != self.exchange.name():
                self.set_exchange(exchange)
                self.currencies = []
                combo.clear()
                self.exchanger.timeout = 0
                hist_checkbox_update()
                set_currencies(combo)
                for window in self.parent.windows:
                    window.update_status()

        def on_change_hist(checked):
            if checked:
                self.config.set_key('history_rates', 'checked')
                self.get_historical_rates()
            else:
                self.config.set_key('history_rates', 'unchecked')

        def set_currencies(combo):
            try:
                combo.blockSignals(True)
                current_currency = self.fiat_unit()
                combo.clear()
            except Exception:
                return
            combo.addItems(self.currencies)
            try:
                index = self.currencies.index(current_currency)
            except Exception:
                index = 0
            combo.blockSignals(False)
            combo.setCurrentIndex(index)

        def ok_clicked():
            if self.exchange in ["CoinDesk", "itBit"]:
                self.timeout = 0
            d.accept();

        hist_checkbox_update()
        set_currencies(combo)
        combo.currentIndexChanged.connect(on_change)
        combo_ex.currentIndexChanged.connect(on_change_ex)
        hist_checkbox.stateChanged.connect(on_change_hist)
        for window in self.parent.windows:
            combo.connect(window, SIGNAL('refresh_currencies_combo()'), lambda: set_currencies(combo))
        combo_ex.connect(d, SIGNAL('refresh_exchanges_combo()'), lambda: set_exchanges(combo_ex))
        ok_button.clicked.connect(lambda: ok_clicked())
        layout.addWidget(combo,1,1)
        layout.addWidget(combo_ex,0,1)
        layout.addWidget(hist_checkbox,2,1)
        layout.addWidget(ok_button,3,1)

        if d.exec_():
            return True
        else:
            return False

    def fiat_unit(self):
        return self.config.get("currency", "EUR")

    def refresh_fields(self):
        '''Update the display at the new rate'''
        for window in self.parent.windows:
            for field in window.fx_fields.values():
                field.textEdited.emit(field.text())

    def add_send_edit(self, window):
        window.send_fiat_e = AmountEdit(self.fiat_unit)
        self.connect_fields(window, True)
        window.send_grid.addWidget(window.send_fiat_e, 4, 3, Qt.AlignHCenter)
        window.amount_e.frozen.connect(lambda: window.send_fiat_e.setFrozen(window.amount_e.isReadOnly()))

    def add_receive_edit(self, window):
        window.receive_fiat_e = AmountEdit(self.fiat_unit)
        self.connect_fields(window, False)
        window.receive_grid.addWidget(window.receive_fiat_e, 2, 3, Qt.AlignHCenter)

    def connect_fields(self, window, send):
        if send:
            btc_e, fiat_e, fee_e = (window.amount_e, window.send_fiat_e,
                                    window.fee_e)
        else:
            btc_e, fiat_e, fee_e = (window.receive_amount_e,
                                    window.receive_fiat_e, None)
        def fiat_changed():
            fiat_e.setStyleSheet(BLACK_FG)
            window.fx_fields[(fiat_e, btc_e)] = fiat_e
            try:
                fiat_amount = Decimal(str(fiat_e.text()))
            except:
                btc_e.setText("")
                if fee_e: fee_e.setText("")
                return
            exchange_rate = self.exchange_rate()
            if exchange_rate is not None:
                btc_amount = fiat_amount/exchange_rate
                btc_e.setAmount(int(btc_amount*Decimal(COIN)))
                btc_e.setStyleSheet(BLUE_FG)
                if fee_e: window.update_fee()
        fiat_e.textEdited.connect(fiat_changed)
        def btc_changed():
            btc_e.setStyleSheet(BLACK_FG)
            window.fx_fields[(fiat_e, btc_e)] = btc_e
            btc_amount = btc_e.get_amount()
            rate = self.exchange_rate()
            if rate is None or btc_amount is None:
                fiat_e.setText("")
            else:
                fiat_amount = rate * Decimal(btc_amount) / Decimal(COIN)
                pos = fiat_e.cursorPosition()
                fiat_e.setText("%.2f"%fiat_amount)
                fiat_e.setCursorPosition(pos)
                fiat_e.setStyleSheet(BLUE_FG)
        btc_e.textEdited.connect(btc_changed)
        window.fx_fields[(fiat_e, btc_e)] = btc_e

    @hook
    def do_clear(self, window):
        window.send_fiat_e.setText('')