import re
import platform
from decimal import Decimal
from urllib import quote

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

from electrum_ltc_gui.qt.qrcodewidget import QRCodeWidget

from electrum_ltc import bmp, pyqrnative, BasePlugin
from electrum_ltc.i18n import _


if platform.system() == 'Windows':
    MONOSPACE_FONT = 'Lucida Console'
elif platform.system() == 'Darwin':
    MONOSPACE_FONT = 'Monaco'
else:
    MONOSPACE_FONT = 'monospace'

column_index = 4

class QR_Window(QWidget):

    def __init__(self, exchanger):
        QWidget.__init__(self)
        self.exchanger = exchanger
        self.setWindowTitle('Electrum - '+_('Invoice'))
        self.setMinimumSize(800, 250)
        self.address = ''
        self.label = ''
        self.amount = 0
        self.setFocusPolicy(QtCore.Qt.NoFocus)

        main_box = QHBoxLayout()
        
        self.qrw = QRCodeWidget()
        main_box.addWidget(self.qrw, 1)

        vbox = QVBoxLayout()
        main_box.addLayout(vbox)

        self.address_label = QLabel("")
        #self.address_label.setFont(QFont(MONOSPACE_FONT))
        vbox.addWidget(self.address_label)

        self.label_label = QLabel("")
        vbox.addWidget(self.label_label)

        self.amount_label = QLabel("")
        vbox.addWidget(self.amount_label)

        vbox.addStretch(1)
        self.setLayout(main_box)


    def set_content(self, addr, label, amount, currency):
        self.address = addr
        address_text = "<span style='font-size: 18pt'>%s</span>" % addr if addr else ""
        self.address_label.setText(address_text)

        if currency == 'LTC': currency = None
        amount_text = ''
        if amount:
            if currency:
                try:
                    self.amount = Decimal(amount) / self.exchanger.exchange(1, currency) if currency else amount
                except Exception:
                    self.amount = None
            else:
                self.amount = Decimal(amount)
            self.amount = self.amount.quantize(Decimal('1.0000'))

            if currency:
                amount_text += "<span style='font-size: 18pt'>%s %s</span><br/>" % (amount, currency)
            amount_text += "<span style='font-size: 21pt'>%s</span> <span style='font-size: 16pt'>LTC</span> " % str(self.amount) 
        else:
            self.amount = None
            
        self.amount_label.setText(amount_text)

        self.label = label
        label_text = "<span style='font-size: 21pt'>%s</span>" % label if label else ""
        self.label_label.setText(label_text)

        msg = 'litecoin:'+self.address
        if self.amount is not None:
            msg += '?amount=%s'%(str( self.amount))
            if self.label is not None:
                encoded_label = quote(self.label)
                msg += '&label=%s'%(encoded_label)
        elif self.label is not None:
            encoded_label = quote(self.label)
            msg += '?label=%s'%(encoded_label)
            
        self.qrw.set_addr( msg )




class Plugin(BasePlugin):

    def fullname(self):
        return 'Point of Sale'

    def description(self):
        return _('Show QR code window and amounts requested for each address. Add menu item to request amount.')+_(' Note: This requires the exchange rate plugin to be installed.')

    def init(self):
        self.window = self.gui.main_window
        self.wallet = self.window.wallet

        self.qr_window = None
        self.merchant_name = self.config.get('merchant_name', 'Invoice')

        self.window.expert_mode = True
        self.window.receive_list.setColumnCount(5)
        self.window.receive_list.setHeaderLabels([ _('Address'), _('Label'), _('Balance'), _('Tx'), _('Request')])
        self.requested_amounts = {}
        self.toggle_QR_window(True)

    def enable(self):
        if not self.config.get('use_exchange_rate'):
            self.gui.main_window.show_message("Please enable exchange rates first!")
            return False

        return BasePlugin.enable(self)


    def load_wallet(self, wallet):
        self.wallet = wallet
        self.requested_amounts = self.wallet.storage.get('requested_amounts',{}) 

    def close(self):
        self.window.receive_list.setHeaderLabels([ _('Address'), _('Label'), _('Balance'), _('Tx')])
        self.window.receive_list.setColumnCount(4)
        for i,width in enumerate(self.window.column_widths['receive']):
            self.window.receive_list.setColumnWidth(i, width)
        self.toggle_QR_window(False)
    

    def close_main_window(self):
        if self.qr_window: 
            self.qr_window.close()
            self.qr_window = None

    
    def timer_actions(self):
        if self.qr_window:
            self.qr_window.qrw.update_qr()


    def toggle_QR_window(self, show):
        if show and not self.qr_window:
            self.qr_window = QR_Window(self.gui.exchanger)
            self.qr_window.setVisible(True)
            self.qr_window_geometry = self.qr_window.geometry()
            item = self.window.receive_list.currentItem()
            if item:
                address = str(item.text(1))
                label = self.wallet.labels.get(address)
                amount, currency = self.requested_amounts.get(address, (None, None))
                self.qr_window.set_content( address, label, amount, currency )

        elif show and self.qr_window and not self.qr_window.isVisible():
            self.qr_window.setVisible(True)
            self.qr_window.setGeometry(self.qr_window_geometry)

        elif not show and self.qr_window and self.qr_window.isVisible():
            self.qr_window_geometry = self.qr_window.geometry()
            self.qr_window.setVisible(False)


    
    def update_receive_item(self, address, item):
        try:
            amount, currency = self.requested_amounts.get(address, (None, None))
        except Exception:
            print "cannot get requested amount", address, self.requested_amounts.get(address)
            amount, currency = None, None
            self.requested_amounts.pop(address)

        amount_str = amount + (' ' + currency if currency else '') if amount is not None  else ''
        item.setData(column_index,0,amount_str)


    
    def current_item_changed(self, a):
        if not self.wallet: 
            return
        if a is not None and self.qr_window and self.qr_window.isVisible():
            address = str(a.text(0))
            label = self.wallet.labels.get(address)
            try:
                amount, currency = self.requested_amounts.get(address, (None, None))
            except Exception:
                amount, currency = None, None
            self.qr_window.set_content( address, label, amount, currency )


    
    def item_changed(self, item, column):
        if column != column_index:
            return
        address = str( item.text(0) )
        text = str( item.text(column) )
        try:
            seq = self.wallet.get_address_index(address)
            index = seq[1][1]
        except Exception:
            print "cannot get index"
            return

        text = text.strip().upper()
        #print text
        m = re.match('^(\d*(|\.\d*))\s*(|LTC|EUR|USD|GBP|CNY|JPY|RUB|BRL)$', text)
        if m and m.group(1) and m.group(1)!='.':
            amount = m.group(1)
            currency = m.group(3)
            if not currency:
                currency = 'LTC'
            else:
                currency = currency.upper()
                    
            self.requested_amounts[address] = (amount, currency)
            self.wallet.storage.put('requested_amounts', self.requested_amounts, True)

            label = self.wallet.labels.get(address)
            if label is None:
                label = self.merchant_name + ' - %04d'%(index+1)
                self.wallet.labels[address] = label

            if self.qr_window:
                self.qr_window.set_content( address, label, amount, currency )

        else:
            item.setText(column,'')
            if address in self.requested_amounts:
                self.requested_amounts.pop(address)
            
        self.window.update_receive_item(self.window.receive_list.currentItem())




    def edit_amount(self):
        l = self.window.receive_list
        item = l.currentItem()
        item.setFlags(Qt.ItemIsEditable|Qt.ItemIsSelectable | Qt.ItemIsUserCheckable | Qt.ItemIsEnabled | Qt.ItemIsDragEnabled)
        l.editItem( item, column_index )
        item.setFlags(Qt.ItemIsSelectable | Qt.ItemIsUserCheckable | Qt.ItemIsEnabled | Qt.ItemIsDragEnabled)

    
    def receive_menu(self, menu, addr):
        menu.addAction(_("Request amount"), self.edit_amount)
        menu.addAction(_("Show Invoice"), lambda: self.toggle_QR_window(True))


