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
  50     def is_available(self):
  51         return self._is_available
  52
  53     def is_enabled(self):
  54         return True
  55
  56     def scan_qr_hook(self):
  57         proc = zbar.Processor()
  58         try:
  59             proc.init(video_device=self.video_device())
  60         except zbar.SystemError, e:
  61             QMessageBox.warning(self.win, _('Error'), _(e), _('OK'))
  62             return
  63
  64         proc.visible = True
  65
  66         while True:
  67             try:
  68                 proc.process_one()
  69             except Exception:
  70                 # User closed the preview window
  71                 return {}
  72
  73             for r in proc.results:
  74                 if str(r.type) != 'QRCODE':
  75                     continue
  76                 return r.data
  77
  78
  79     def video_device(self):
  80         device = self.config.get("video_device", "default")
  81         if device == 'default':
  82             device = ''
  83         return device
  84
  85     def requires_settings(self):
  86         return True
  87
  88     def settings_widget(self, window):
  89         return EnterButton(_('Settings'), self.settings_dialog)
  90
  91     def _find_system_cameras(self):
  92         device_root = "/sys/class/video4linux"
  93         devices = {} # Name -> device
  94         if os.path.exists(device_root):
  95             for device in os.listdir(device_root):
  96                 name = open(os.path.join(device_root, device, 'name')).read()
  97                 devices[name] = os.path.join("/dev",device)
  98         return devices
  99
 100     def settings_dialog(self):
 101         system_cameras = self._find_system_cameras()
 102
 103         d = QDialog()
 104         layout = QGridLayout(d)
 105         layout.addWidget(QLabel("Choose a video device:"),0,0)
 106
 107         # Create a combo box with the available video devices:
 108         combo = QComboBox()
 109
 110         # on change trigger for video device selection, makes the
 111         # manual device selection only appear when needed:
 112         def on_change(x):
 113             combo_text = str(combo.itemText(x))
 114             combo_data = combo.itemData(x)
 115             if combo_text == "Manually specify a device":
 116                 custom_device_label.setVisible(True)
 117                 self.video_device_edit.setVisible(True)
 118                 if self.config.get("video_device") == "default":
 119                     self.video_device_edit.setText("")
 120                 else:
 121                     self.video_device_edit.setText(self.config.get("video_device",''))
 122             else:
 123                 custom_device_label.setVisible(False)
 124                 self.video_device_edit.setVisible(False)
 125                 self.video_device_edit.setText(combo_data.toString())
 126
 127         # on save trigger for the video device selection window,
 128         # stores the chosen video device on close.
 129         def on_save():
 130             device = str(self.video_device_edit.text())
 131             self.config.set_key("video_device", device)
 132             d.accept()
 133
 134         custom_device_label = QLabel("Video device: ")
 135         custom_device_label.setVisible(False)
 136         layout.addWidget(custom_device_label,1,0)
 137         self.video_device_edit = QLineEdit()
 138         self.video_device_edit.setVisible(False)
 139         layout.addWidget(self.video_device_edit, 1,1,2,2)
 140         combo.currentIndexChanged.connect(on_change)
 141
 142         combo.addItem("Default","default")
 143         for camera, device in system_cameras.items():
 144             combo.addItem(camera, device)
 145         combo.addItem("Manually specify a device",self.config.get("video_device"))
 146
 147         # Populate the previously chosen device:
 148         index = combo.findData(self.config.get("video_device"))
 149         combo.setCurrentIndex(index)
 150
 151         layout.addWidget(combo,0,1)
 152
 153         self.accept = QPushButton(_("Done"))
 154         self.accept.clicked.connect(on_save)
 155         layout.addWidget(self.accept,4,2)
 156
 157         if d.exec_():
 158           return True
 159         else:
 160           return False