plugins/qrscanner.py

   1 from electrum_nvc.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_nvc.i18n import _
   7 import re
   8 import os
   9 from electrum_nvc import Transaction
  10 from electrum_nvc.bitcoin import MIN_RELAY_TX_FEE, is_valid
  11 from electrum_nvc_gui.qt.qrcodewidget import QRCodeWidget
  12 from electrum_nvc import bmp
  13 from electrum_nvc_gui.qt import HelpButton, EnterButton
  14 import json
  15
  16 try:
  17     import zbar
  18 except ImportError:
  19     zbar = None
  20
  21 from electrum_nvc 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
  44         return True
  45
  46     def init(self):
  47         self.win = self.gui.main_window
  48
  49     def is_available(self):
  50         return self._is_available
  51
  52     def is_enabled(self):
  53         return True
  54
  55     def scan_qr_hook(self):
  56         proc = zbar.Processor()
  57         try:
  58             proc.init(video_device=self.video_device())
  59         except zbar.SystemError, e:
  60             QMessageBox.warning(self.win, _('Error'), _(e), _('OK'))
  61             return
  62
  63         proc.visible = True
  64
  65         while True:
  66             try:
  67                 proc.process_one()
  68             except Exception:
  69                 # User closed the preview window
  70                 return {}
  71
  72             for r in proc.results:
  73                 if str(r.type) != 'QRCODE':
  74                     continue
  75                 return r.data
  76
  77
  78     def video_device(self):
  79         device = self.config.get("video_device", "default")
  80         if device == 'default':
  81             device = ''
  82         return device
  83
  84     def requires_settings(self):
  85         return True
  86
  87     def settings_widget(self, window):
  88         return EnterButton(_('Settings'), self.settings_dialog)
  89
  90     def _find_system_cameras(self):
  91         device_root = "/sys/class/video4linux"
  92         devices = {} # Name -> device
  93         if os.path.exists(device_root):
  94             for device in os.listdir(device_root):
  95                 name = open(os.path.join(device_root, device, 'name')).read()
  96                 devices[name] = os.path.join("/dev",device)
  97         return devices
  98
  99     def settings_dialog(self):
 100         system_cameras = self._find_system_cameras()
 101
 102         d = QDialog()
 103         layout = QGridLayout(d)
 104         layout.addWidget(QLabel("Choose a video device:"),0,0)
 105
 106         # Create a combo box with the available video devices:
 107         combo = QComboBox()
 108
 109         # on change trigger for video device selection, makes the
 110         # manual device selection only appear when needed:
 111         def on_change(x):
 112             combo_text = str(combo.itemText(x))
 113             combo_data = combo.itemData(x)
 114             if combo_text == "Manually specify a device":
 115                 custom_device_label.setVisible(True)
 116                 self.video_device_edit.setVisible(True)
 117                 if self.config.get("video_device") == "default":
 118                     self.video_device_edit.setText("")
 119                 else:
 120                     self.video_device_edit.setText(self.config.get("video_device",''))
 121             else:
 122                 custom_device_label.setVisible(False)
 123                 self.video_device_edit.setVisible(False)
 124                 self.video_device_edit.setText(combo_data.toString())
 125
 126         # on save trigger for the video device selection window,
 127         # stores the chosen video device on close.
 128         def on_save():
 129             device = str(self.video_device_edit.text())
 130             self.config.set_key("video_device", device)
 131             d.accept()
 132
 133         custom_device_label = QLabel("Video device: ")
 134         custom_device_label.setVisible(False)
 135         layout.addWidget(custom_device_label,1,0)
 136         self.video_device_edit = QLineEdit()
 137         self.video_device_edit.setVisible(False)
 138         layout.addWidget(self.video_device_edit, 1,1,2,2)
 139         combo.currentIndexChanged.connect(on_change)
 140
 141         combo.addItem("Default","default")
 142         for camera, device in system_cameras.items():
 143             combo.addItem(camera, device)
 144         combo.addItem("Manually specify a device",self.config.get("video_device"))
 145
 146         # Populate the previously chosen device:
 147         index = combo.findData(self.config.get("video_device"))
 148         combo.setCurrentIndex(index)
 149
 150         layout.addWidget(combo,0,1)
 151
 152         self.accept = QPushButton(_("Done"))
 153         self.accept.clicked.connect(on_save)
 154         layout.addWidget(self.accept,4,2)
 155
 156         if d.exec_():
 157           return True
 158         else:
 159           return False