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.UnsupportedError:
  39             return False
  40         except zbar.SystemError:
  41             # Cannot open video device
  42             pass
  43             #return False
  44
  45         return True
  46
  47     def init(self):
  48         self.win = self.gui.main_window
  49         self.win.raw_transaction_menu.addAction(_("&From QR code"), self.read_raw_qr)
  50
  51     def is_available(self):
  52         return self._is_available
  53
  54     def scan_qr_hook(self, func):
  55         data = self.scan_qr()
  56         if type(data) != str:
  57             return
  58         func(data)
  59
  60     def scan_qr(self):
  61         proc = zbar.Processor()
  62         try:
  63             proc.init(video_device=self.video_device())
  64         except zbar.SystemError, e:
  65             QMessageBox.warning(self.win, _('Error'), _(e), _('OK'))
  66             return
  67
  68         proc.visible = True
  69
  70         while True:
  71             try:
  72                 proc.process_one()
  73             except Exception:
  74                 # User closed the preview window
  75                 return {}
  76
  77             for r in proc.results:
  78                 if str(r.type) != 'QRCODE':
  79                     continue
  80                 return r.data
  81
  82
  83     def read_raw_qr(self):
  84         qrcode = self.scan_qr()
  85         if not qrcode:
  86             return
  87         data = qrcode
  88
  89         # transactions are binary, but qrcode seems to return utf8...
  90         z = data.decode('utf8')
  91         s = ''
  92         for b in z:
  93             s += chr(ord(b))
  94         data = s.encode('hex')
  95         tx = self.win.tx_from_text(data)
  96         if not tx:
  97             return
  98         self.win.show_transaction(tx)
  99
 100     def video_device(self):
 101         device = self.config.get("video_device", "default")
 102         if device == 'default':
 103             device = ''
 104         return device
 105
 106     def requires_settings(self):
 107         return True
 108
 109     def settings_widget(self, window):
 110         return EnterButton(_('Settings'), self.settings_dialog)
 111
 112     def _find_system_cameras(self):
 113         device_root = "/sys/class/video4linux"
 114         devices = {} # Name -> device
 115         if os.path.exists(device_root):
 116             for device in os.listdir(device_root):
 117                 name = open(os.path.join(device_root, device, 'name')).read()
 118                 devices[name] = os.path.join("/dev",device)
 119         return devices
 120
 121     def settings_dialog(self):
 122         system_cameras = self._find_system_cameras()
 123
 124         d = QDialog()
 125         layout = QGridLayout(d)
 126         layout.addWidget(QLabel("Choose a video device:"),0,0)
 127
 128         # Create a combo box with the available video devices:
 129         combo = QComboBox()
 130
 131         # on change trigger for video device selection, makes the
 132         # manual device selection only appear when needed:
 133         def on_change(x):
 134             combo_text = str(combo.itemText(x))
 135             combo_data = combo.itemData(x)
 136             if combo_text == "Manually specify a device":
 137                 custom_device_label.setVisible(True)
 138                 self.video_device_edit.setVisible(True)
 139                 if self.config.get("video_device") == "default":
 140                     self.video_device_edit.setText("")
 141                 else:
 142                     self.video_device_edit.setText(self.config.get("video_device",''))
 143             else:
 144                 custom_device_label.setVisible(False)
 145                 self.video_device_edit.setVisible(False)
 146                 self.video_device_edit.setText(combo_data.toString())
 147
 148         # on save trigger for the video device selection window,
 149         # stores the chosen video device on close.
 150         def on_save():
 151             device = str(self.video_device_edit.text())
 152             self.config.set_key("video_device", device)
 153             d.accept()
 154
 155         custom_device_label = QLabel("Video device: ")
 156         custom_device_label.setVisible(False)
 157         layout.addWidget(custom_device_label,1,0)
 158         self.video_device_edit = QLineEdit()
 159         self.video_device_edit.setVisible(False)
 160         layout.addWidget(self.video_device_edit, 1,1,2,2)
 161         combo.currentIndexChanged.connect(on_change)
 162
 163         combo.addItem("Default","default")
 164         for camera, device in system_cameras.items():
 165             combo.addItem(camera, device)
 166         combo.addItem("Manually specify a device",self.config.get("video_device"))
 167
 168         # Populate the previously chosen device:
 169         index = combo.findData(self.config.get("video_device"))
 170         combo.setCurrentIndex(index)
 171
 172         layout.addWidget(combo,0,1)
 173
 174         self.accept = QPushButton(_("Done"))
 175         self.accept.clicked.connect(on_save)
 176         layout.addWidget(self.accept,4,2)
 177
 178         if d.exec_():
 179           return True
 180         else:
 181           return False