from binascii import hexlify, unhexlify

from PyQt5.Qt import QDialog, QLineEdit, QTextEdit, QVBoxLayout, QLabel
import PyQt5.QtCore as QtCore
from PyQt5.QtWidgets import *

from electrum.i18n import _
from electrum_gui.qt.util import *
from electrum.util import print_msg

import os, hashlib, websocket, logging, json, copy
from electrum_gui.qt.qrcodewidget import QRCodeWidget
from btchip.btchip import *

DEBUG = False

helpTxt = [_("Your Ledger Wallet wants to tell you a one-time PIN code.<br><br>" \
            "For best security you should unplug your device, open a text editor on another computer, " \
            "put your cursor into it, and plug your device into that computer. " \
            "It will output a summary of the transaction being signed and a one-time PIN.<br><br>" \
            "Verify the transaction summary and type the PIN code here.<br><br>" \
            "Before pressing enter, plug the device back into this computer.<br>" ),
        _("Verify the address below.<br>Type the character from your security card corresponding to the <u><b>BOLD</b></u> character."),
        _("Waiting for authentication on your mobile phone"),
        _("Transaction accepted by mobile phone. Waiting for confirmation."),
        _("Click Pair button to begin pairing a mobile phone."),
        _("Scan this QR code with your LedgerWallet phone app to pair it with this Ledger device.<br>" 
            "To complete pairing you will need your security card to answer a challenge." )
        ]

class LedgerAuthDialog(QDialog):
    def __init__(self, handler, data):
        '''Ask user for 2nd factor authentication. Support text, security card and paired mobile methods.
        Use last method from settings, but support new pairing and downgrade.
        '''
        QDialog.__init__(self, handler.top_level_window())
        self.handler = handler
        self.txdata = data
        self.idxs = self.txdata['keycardData'] if self.txdata['confirmationType'] > 1 else ''
        self.setMinimumWidth(600)
        self.setWindowTitle(_("Ledger Wallet Authentication"))
        self.cfg = copy.deepcopy(self.handler.win.wallet.get_keystore().cfg)
        self.dongle = self.handler.win.wallet.get_keystore().get_client().dongle
        self.ws = None
        self.pin = ''
        
        self.devmode = self.getDevice2FAMode()
        if self.devmode == 0x11 or self.txdata['confirmationType'] == 1:
            self.cfg['mode'] = 0
        
        vbox = QVBoxLayout()
        self.setLayout(vbox)
        
        def on_change_mode(idx):
            if idx < 2 and self.ws:
                self.ws.stop()
                self.ws = None
            self.cfg['mode'] = 0 if self.devmode == 0x11 else idx if idx > 0 else 1
            if self.cfg['mode'] > 1 and self.cfg['pair'] and not self.ws:
                self.req_validation()
            if self.cfg['mode'] > 0:
                self.handler.win.wallet.get_keystore().cfg = self.cfg
                self.handler.win.wallet.save_keystore()
            self.update_dlg()
        def add_pairing():
            self.do_pairing()
        def return_pin():
            self.pin = self.pintxt.text() if self.txdata['confirmationType'] == 1 else self.cardtxt.text() 
            if self.cfg['mode'] == 1:
                self.pin = ''.join(chr(int(str(i),16)) for i in self.pin)
            self.accept()
        
        self.modebox = QWidget()
        modelayout = QHBoxLayout()
        self.modebox.setLayout(modelayout)
        modelayout.addWidget(QLabel(_("Method:")))
        self.modes = QComboBox()
        modelayout.addWidget(self.modes, 2)
        self.addPair = QPushButton(_("Pair"))
        self.addPair.setMaximumWidth(60)
        modelayout.addWidget(self.addPair)
        modelayout.addStretch(1)
        self.modebox.setMaximumHeight(50)
        vbox.addWidget(self.modebox)
        
        self.populate_modes()
        self.modes.currentIndexChanged.connect(on_change_mode)
        self.addPair.clicked.connect(add_pairing)
        
        self.helpmsg = QTextEdit()
        self.helpmsg.setStyleSheet("QTextEdit { background-color: lightgray; }")
        self.helpmsg.setReadOnly(True)
        vbox.addWidget(self.helpmsg)
        
        self.pinbox = QWidget()
        pinlayout = QHBoxLayout()
        self.pinbox.setLayout(pinlayout)
        self.pintxt = QLineEdit()
        self.pintxt.setEchoMode(2)
        self.pintxt.setMaxLength(4)
        self.pintxt.returnPressed.connect(return_pin)
        pinlayout.addWidget(QLabel(_("Enter PIN:")))
        pinlayout.addWidget(self.pintxt)
        pinlayout.addWidget(QLabel(_("NOT DEVICE PIN - see above")))
        pinlayout.addStretch(1)
        self.pinbox.setVisible(self.cfg['mode'] == 0)
        vbox.addWidget(self.pinbox)
                    
        self.cardbox = QWidget()
        card = QVBoxLayout()
        self.cardbox.setLayout(card)
        self.addrtext = QTextEdit()
        self.addrtext.setStyleSheet("QTextEdit { color:blue; background-color:lightgray; padding:15px 10px; border:none; font-size:20pt; }")
        self.addrtext.setReadOnly(True)
        self.addrtext.setMaximumHeight(120)
        card.addWidget(self.addrtext)
        
        def pin_changed(s):
            if len(s) < len(self.idxs):
                i = self.idxs[len(s)]
                addr = self.txdata['address']
                addr = addr[:i] + '<u><b>' + addr[i:i+1] + '</u></b>' + addr[i+1:]
                self.addrtext.setHtml(str(addr))
            else:
                self.addrtext.setHtml(_("Press Enter"))
                
        pin_changed('')    
        cardpin = QHBoxLayout()
        cardpin.addWidget(QLabel(_("Enter PIN:")))
        self.cardtxt = QLineEdit()
        self.cardtxt.setEchoMode(2)
        self.cardtxt.setMaxLength(len(self.idxs))
        self.cardtxt.textChanged.connect(pin_changed)
        self.cardtxt.returnPressed.connect(return_pin)
        cardpin.addWidget(self.cardtxt)
        cardpin.addWidget(QLabel(_("NOT DEVICE PIN - see above")))
        cardpin.addStretch(1)
        card.addLayout(cardpin)
        self.cardbox.setVisible(self.cfg['mode'] == 1)
        vbox.addWidget(self.cardbox)
        
        self.pairbox = QWidget()
        pairlayout = QVBoxLayout()
        self.pairbox.setLayout(pairlayout)
        pairhelp = QTextEdit(helpTxt[5])
        pairhelp.setStyleSheet("QTextEdit { background-color: lightgray; }")
        pairhelp.setReadOnly(True)
        pairlayout.addWidget(pairhelp, 1)
        self.pairqr = QRCodeWidget()
        pairlayout.addWidget(self.pairqr, 4)
        self.pairbox.setVisible(False)
        vbox.addWidget(self.pairbox)
        self.update_dlg()
        
        if self.cfg['mode'] > 1 and not self.ws:
            self.req_validation()
        
    def populate_modes(self):
        self.modes.blockSignals(True)
        self.modes.clear()
        self.modes.addItem(_("Summary Text PIN (requires dongle replugging)") if self.txdata['confirmationType'] == 1 else _("Summary Text PIN is Disabled"))
        if self.txdata['confirmationType'] > 1:
            self.modes.addItem(_("Security Card Challenge"))
            if not self.cfg['pair']:
                self.modes.addItem(_("Mobile - Not paired")) 
            else:
                self.modes.addItem(_("Mobile - {}").format(self.cfg['pair'][1]))
        self.modes.blockSignals(False)
        
    def update_dlg(self):
        self.modes.setCurrentIndex(self.cfg['mode'])
        self.modebox.setVisible(True)
        self.addPair.setText(_("Pair") if not self.cfg['pair'] else _("Re-Pair"))
        self.addPair.setVisible(self.txdata['confirmationType'] > 2)
        self.helpmsg.setText(helpTxt[self.cfg['mode'] if self.cfg['mode'] < 2 else 2 if self.cfg['pair'] else 4])
        self.helpmsg.setMinimumHeight(180 if self.txdata['confirmationType'] == 1 else 100)
        self.pairbox.setVisible(False)
        self.helpmsg.setVisible(True)
        self.pinbox.setVisible(self.cfg['mode'] == 0)
        self.cardbox.setVisible(self.cfg['mode'] == 1)
        self.pintxt.setFocus(True) if self.cfg['mode'] == 0 else self.cardtxt.setFocus(True)
        self.setMaximumHeight(200)
        
    def do_pairing(self):
        rng = os.urandom(16)
        pairID = (hexlify(rng) + hexlify(hashlib.sha256(rng).digest()[0:1])).decode('utf-8')
        self.pairqr.setData(pairID)
        self.modebox.setVisible(False)
        self.helpmsg.setVisible(False)
        self.pinbox.setVisible(False)
        self.cardbox.setVisible(False)
        self.pairbox.setVisible(True)
        self.pairqr.setMinimumSize(300,300)
        if self.ws:
            self.ws.stop()
        self.ws = LedgerWebSocket(self, pairID)
        self.ws.pairing_done.connect(self.pairing_done)
        self.ws.start() 
               
    def pairing_done(self, data):
        if data is not None:
            self.cfg['pair'] = [ data['pairid'], data['name'], data['platform'] ]
            self.cfg['mode'] = 2
            self.handler.win.wallet.get_keystore().cfg = self.cfg
            self.handler.win.wallet.save_keystore()
        self.pin = 'paired'
        self.accept()
    
    def req_validation(self):
        if self.cfg['pair'] and 'secureScreenData' in self.txdata:
            if self.ws:
                self.ws.stop()
            self.ws = LedgerWebSocket(self, self.cfg['pair'][0], self.txdata)
            self.ws.req_updated.connect(self.req_updated)
            self.ws.start()
              
    def req_updated(self, pin):
        if pin == 'accepted':
            self.helpmsg.setText(helpTxt[3])
        else:
            self.pin = str(pin)
            self.accept()
        
    def getDevice2FAMode(self):
        apdu = [0xe0, 0x24, 0x01, 0x00, 0x00, 0x01] # get 2fa mode
        try:
            mode = self.dongle.exchange( bytearray(apdu) )
            return mode
        except BTChipException as e:
            debug_msg('Device getMode Failed')
        return 0x11
    
    def closeEvent(self, evnt):
        debug_msg("CLOSE - Stop WS")
        if self.ws:
            self.ws.stop()
        if self.pairbox.isVisible():
            evnt.ignore()
            self.update_dlg()

class LedgerWebSocket(QThread):
    pairing_done = pyqtSignal(object)
    req_updated = pyqtSignal(str)
    
    def __init__(self, dlg, pairID, txdata=None):
        QThread.__init__(self)
        self.stopping = False
        self.pairID = pairID
        self.txreq = '{"type":"request","second_factor_data":"' + hexlify(txdata['secureScreenData']).decode('utf-8') + '"}' if txdata else None
        self.dlg = dlg
        self.dongle = self.dlg.dongle
        self.data = None
             
        #websocket.enableTrace(True)
        logging.basicConfig(level=logging.INFO)
        self.ws = websocket.WebSocketApp('wss://ws.ledgerwallet.com/2fa/channels', 
                                on_message = self.on_message, on_error = self.on_error,
                                on_close = self.on_close, on_open = self.on_open)
                                
    def run(self):
        while not self.stopping:
            self.ws.run_forever()
    def stop(self):
        debug_msg("WS: Stopping")
        self.stopping = True
        self.ws.close()

    def on_message(self, ws, msg):
        data = json.loads(msg)
        if data['type'] == 'identify':
            debug_msg('Identify')
            apdu = [0xe0, 0x12, 0x01, 0x00, 0x41] # init pairing
            apdu.extend(unhexlify(data['public_key']))
            try:
                challenge = self.dongle.exchange( bytearray(apdu) )
                ws.send( '{"type":"challenge","data":"%s" }' % hexlify(challenge).decode('utf-8') )
                self.data = data
            except BTChipException as e:
                debug_msg('Identify Failed')
                
        if data['type'] == 'challenge':
            debug_msg('Challenge')
            apdu = [0xe0, 0x12, 0x02, 0x00, 0x10] # confirm pairing
            apdu.extend(unhexlify(data['data']))
            try:
                self.dongle.exchange( bytearray(apdu) )
                debug_msg('Pairing Successful')
                ws.send( '{"type":"pairing","is_successful":"true"}' )
                self.data['pairid'] = self.pairID
                self.pairing_done.emit(self.data)
            except BTChipException as e:
                debug_msg('Pairing Failed')
                ws.send( '{"type":"pairing","is_successful":"false"}' ) 
                self.pairing_done.emit(None)
            ws.send( '{"type":"disconnect"}' )
            self.stopping = True
            ws.close()
        
        if data['type'] == 'accept':
            debug_msg('Accepted')
            self.req_updated.emit('accepted')
        if data['type'] == 'response':
            debug_msg('Responded', data)
            self.req_updated.emit(str(data['pin']) if data['is_accepted'] else '')
            self.txreq = None
            self.stopping = True
            ws.close()
            
        if data['type'] == 'repeat':
            debug_msg('Repeat')
            if self.txreq:
                ws.send( self.txreq )
                debug_msg("Req Sent", self.txreq)
        if data['type'] == 'connect':
            debug_msg('Connected')
            if self.txreq:
                ws.send( self.txreq )
                debug_msg("Req Sent", self.txreq)
        if data['type'] == 'disconnect':
            debug_msg('Disconnected')
            ws.close()
            
    def on_error(self, ws, error):
        message = getattr(error, 'strerror', '')
        if not message:
            message = getattr(error, 'message', '')
        debug_msg("WS: %s" % message)
    
    def on_close(self, ws):
        debug_msg("WS: ### socket closed ###")
    
    def on_open(self, ws):
        debug_msg("WS: ### socket open ###")
        debug_msg("Joining with pairing ID", self.pairID)
        ws.send( '{"type":"join","room":"%s"}' % self.pairID )
        ws.send( '{"type":"repeat"}' )
        if self.txreq:
            ws.send( self.txreq )
            debug_msg("Req Sent", self.txreq)

def debug_msg(*args):
    if DEBUG:
        print_msg(*args)        

    
        
        
        
