plugins/qrscanner.py

   1 from electrum.util import print_error
   2 from urlparse import urlparse, parse_qs
   3 from PyQt4.QtGui import QPushButton, QMessageBox, QDialog, QVBoxLayout, QHBoxLayout, QGridLayout, QLabel, QLineEdit, QComboBox
   4 from PyQt4.QtCore import Qt
   5
   6 from electrum.i18n import _
   7 import re
   8 import os
   9 from electrum import Transaction
  10 from electrum.bitcoin import MIN_RELAY_TX_FEE, is_valid
  11 from electrum_gui.qt.qrcodewidget import QRCodeWidget
  12 from electrum import bmp
  13 from electrum_gui.qt import HelpButton, EnterButton
  14 import json
  15
  16 try:
  17     import zbar
  18 except ImportError:
  19     zbar = None
  20
  21 from electrum import BasePlugin
  22 class Plugin(BasePlugin):
  23
  24     def fullname(self): return 'QR scans'
  25
  26     def description(self): return "QR Scans.\nInstall the zbar package to enable this plugin.\nOn linux, type: 'apt-get install python-zbar'"
  27
  28     def __init__(self, gui, name):
  29         BasePlugin.__init__(self, gui, name)
  30         self._is_available = self._init()
  31
  32     def _init(self):
  33         if not zbar:
  34             return False
  35         try:
  36             proc = zbar.Processor()
  37             proc.init(video_device=self.video_device())
  38         except zbar.SystemError:
  39             # Cannot open video device
  40             pass
  41             #return False
  42
  43         return True
  44
  45     def init(self):
  46         self.win = self.gui.main_window
  47         self.win.raw_transaction_menu.addAction(_("&From QR code"), self.read_raw_qr)
  48
  49     def is_available(self):
  50         return self._is_available
  51
  52     def scan_qr_hook(self, func):
  53         data = self.scan_qr()
  54         if type(data) != str:
  55             return
  56         func(data)
  57
  58     def scan_qr(self):
  59         proc = zbar.Processor()
  60         try:
  61             proc.init(video_device=self.video_device())
  62         except zbar.SystemError, e:
  63             QMessageBox.warning(self.win, _('Error'), _(e), _('OK'))
  64             return
  65
  66         proc.visible = True
  67
  68         while True:
  69             try:
  70                 proc.process_one()
  71             except Exception:
  72                 # User closed the preview window
  73                 return {}
  74
  75             for r in proc.results:
  76                 if str(r.type) != 'QRCODE':
  77                     continue
  78                 return r.data
  79
  80
  81     def read_raw_qr(self):
  82         qrcode = self.scan_qr()
  83         if not qrcode:
  84             return
  85         data = qrcode
  86
  87         # transactions are binary, but qrcode seems to return utf8...
  88         z = data.decode('utf8')
  89         s = ''
  90         for b in z:
  91             s += chr(ord(b))
  92         data = s.encode('hex')
  93         tx = self.win.tx_from_text(data)
  94         if not tx:
  95             return
  96         self.win.show_transaction(tx)
  97
  98     def video_device(self):
  99         device = self.config.get("video_device", "default")
 100         if device == 'default':
 101             device = ''
 102         return device
 103
 104     def requires_settings(self):
 105         return True
 106
 107     def settings_widget(self, window):
 108         return EnterButton(_('Settings'), self.settings_dialog)
 109
 110     def _find_system_cameras(self):
 111         device_root = "/sys/class/video4linux"
 112         devices = {} # Name -> device
 113         if os.path.exists(device_root):
 114             for device in os.listdir(device_root):
 115                 name = open(os.path.join(device_root, device, 'name')).read()
 116                 devices[name] = os.path.join("/dev",device)
 117         return devices
 118
 119     def settings_dialog(self):
 120         system_cameras = self._find_system_cameras()
 121
 122         d = QDialog()
 123         layout = QGridLayout(d)
 124         layout.addWidget(QLabel("Choose a video device:"),0,0)
 125
 126         # Create a combo box with the available video devices:
 127         combo = QComboBox()
 128
 129         # on change trigger for video device selection, makes the
 130         # manual device selection only appear when needed:
 131         def on_change(x):
 132             combo_text = str(combo.itemText(x))
 133             combo_data = combo.itemData(x)
 134             if combo_text == "Manually specify a device":
 135                 custom_device_label.setVisible(True)
 136                 self.video_device_edit.setVisible(True)
 137                 if self.config.get("video_device") == "default":
 138                     self.video_device_edit.setText("")
 139                 else:
 140                     self.video_device_edit.setText(self.config.get("video_device",''))
 141             else:
 142                 custom_device_label.setVisible(False)
 143                 self.video_device_edit.setVisible(False)
 144                 self.video_device_edit.setText(combo_data.toString())
 145
 146         # on save trigger for the video device selection window,
 147         # stores the chosen video device on close.
 148         def on_save():
 149             device = str(self.video_device_edit.text())
 150             self.config.set_key("video_device", device)
 151             d.accept()
 152
 153         custom_device_label = QLabel("Video device: ")
 154         custom_device_label.setVisible(False)
 155         layout.addWidget(custom_device_label,1,0)
 156         self.video_device_edit = QLineEdit()
 157         self.video_device_edit.setVisible(False)
 158         layout.addWidget(self.video_device_edit, 1,1,2,2)
 159         combo.currentIndexChanged.connect(on_change)
 160
 161         combo.addItem("Default","default")
 162         for camera, device in system_cameras.items():
 163             combo.addItem(camera, device)
 164         combo.addItem("Manually specify a device",self.config.get("video_device"))
 165
 166         # Populate the previously chosen device:
 167         index = combo.findData(self.config.get("video_device"))
 168         combo.setCurrentIndex(index)
 169
 170         layout.addWidget(combo,0,1)
 171
 172         self.accept = QPushButton(_("Done"))
 173         self.accept.clicked.connect(on_save)
 174         layout.addWidget(self.accept,4,2)
 175
 176         if d.exec_():
 177           return True
 178         else:
 179           return False