gui/qt_console.py

   1 # source: http://stackoverflow.com/questions/2758159/how-to-embed-a-python-interpreter-in-a-pyqt-widget
   2
   3 import sys, os, re
   4 import traceback
   5 from PyQt4 import QtCore
   6 from PyQt4 import QtGui
   7 from electrum import util
   8
   9
  10
  11 class Console(QtGui.QPlainTextEdit):
  12     def __init__(self, prompt='>> ', startup_message='', parent=None):
  13         QtGui.QPlainTextEdit.__init__(self, parent)
  14
  15         self.prompt = prompt
  16         self.history = []
  17         self.namespace = {}
  18         self.construct = []
  19
  20         self.setGeometry(50, 75, 600, 400)
  21         self.setWordWrapMode(QtGui.QTextOption.WrapAnywhere)
  22         self.setUndoRedoEnabled(False)
  23         self.document().setDefaultFont(QtGui.QFont("monospace", 10, QtGui.QFont.Normal))
  24         self.showMessage(startup_message)
  25
  26         self.updateNamespace({'run':self.run_script})
  27         self.set_json(False)
  28
  29     def set_json(self, b):
  30         self.is_json = b
  31
  32     def run_script(self, filename):
  33         with open(filename) as f:
  34             script = f.read()
  35         result = eval(script, self.namespace, self.namespace)
  36
  37
  38
  39     def updateNamespace(self, namespace):
  40         self.namespace.update(namespace)
  41
  42     def showMessage(self, message):
  43         self.appendPlainText(message)
  44         self.newPrompt()
  45
  46     def clear(self):
  47         self.setPlainText('')
  48         self.newPrompt()
  49
  50     def newPrompt(self):
  51         if self.construct:
  52             prompt = '.' * len(self.prompt)
  53         else:
  54             prompt = self.prompt
  55
  56         self.completions_pos = self.textCursor().position()
  57         self.completions_visible = False
  58
  59         self.appendPlainText(prompt)
  60         self.moveCursor(QtGui.QTextCursor.End)
  61
  62     def getCommand(self):
  63         doc = self.document()
  64         curr_line = unicode(doc.findBlockByLineNumber(doc.lineCount() - 1).text())
  65         curr_line = curr_line.rstrip()
  66         curr_line = curr_line[len(self.prompt):]
  67         return curr_line
  68
  69     def setCommand(self, command):
  70         if self.getCommand() == command:
  71             return
  72         self.moveCursor(QtGui.QTextCursor.End)
  73         self.moveCursor(QtGui.QTextCursor.StartOfLine, QtGui.QTextCursor.KeepAnchor)
  74         for i in range(len(self.prompt)):
  75             self.moveCursor(QtGui.QTextCursor.Right, QtGui.QTextCursor.KeepAnchor)
  76         self.textCursor().removeSelectedText()
  77         self.textCursor().insertText(command)
  78         self.moveCursor(QtGui.QTextCursor.End)
  79
  80
  81     def show_completions(self, completions):
  82         if self.completions_visible:
  83             self.hide_completions()
  84
  85         c = self.textCursor()
  86         c.setPosition(self.completions_pos)
  87
  88         completions = map(lambda x: x.split('.')[-1], completions)
  89         t = '\n' + ' '.join(completions)
  90         if len(t) > 500:
  91             t = t[:500] + '...'
  92         c.insertText(t)
  93         self.completions_end = c.position()
  94
  95         self.moveCursor(QtGui.QTextCursor.End)
  96         self.completions_visible = True
  97
  98
  99     def hide_completions(self):
 100         if not self.completions_visible:
 101             return
 102         c = self.textCursor()
 103         c.setPosition(self.completions_pos)
 104         l = self.completions_end - self.completions_pos
 105         for x in range(l): c.deleteChar()
 106
 107         self.moveCursor(QtGui.QTextCursor.End)
 108         self.completions_visible = False
 109
 110
 111     def getConstruct(self, command):
 112         if self.construct:
 113             prev_command = self.construct[-1]
 114             self.construct.append(command)
 115             if not prev_command and not command:
 116                 ret_val = '\n'.join(self.construct)
 117                 self.construct = []
 118                 return ret_val
 119             else:
 120                 return ''
 121         else:
 122             if command and command[-1] == (':'):
 123                 self.construct.append(command)
 124                 return ''
 125             else:
 126                 return command
 127
 128     def getHistory(self):
 129         return self.history
 130
 131     def setHisory(self, history):
 132         self.history = history
 133
 134     def addToHistory(self, command):
 135         if command and (not self.history or self.history[-1] != command):
 136             self.history.append(command)
 137         self.history_index = len(self.history)
 138
 139     def getPrevHistoryEntry(self):
 140         if self.history:
 141             self.history_index = max(0, self.history_index - 1)
 142             return self.history[self.history_index]
 143         return ''
 144
 145     def getNextHistoryEntry(self):
 146         if self.history:
 147             hist_len = len(self.history)
 148             self.history_index = min(hist_len, self.history_index + 1)
 149             if self.history_index < hist_len:
 150                 return self.history[self.history_index]
 151         return ''
 152
 153     def getCursorPosition(self):
 154         return self.textCursor().columnNumber() - len(self.prompt)
 155
 156     def setCursorPosition(self, position):
 157         self.moveCursor(QtGui.QTextCursor.StartOfLine)
 158         for i in range(len(self.prompt) + position):
 159             self.moveCursor(QtGui.QTextCursor.Right)
 160
 161     def runCommand(self):
 162         command = self.getCommand()
 163         self.addToHistory(command)
 164
 165         command = self.getConstruct(command)
 166
 167         if command:
 168             tmp_stdout = sys.stdout
 169
 170             class stdoutProxy():
 171                 def __init__(self, write_func):
 172                     self.write_func = write_func
 173                     self.skip = False
 174
 175                 def flush(self):
 176                     pass
 177
 178                 def write(self, text):
 179                     if not self.skip:
 180                         stripped_text = text.rstrip('\n')
 181                         self.write_func(stripped_text)
 182                         QtCore.QCoreApplication.processEvents()
 183                     self.skip = not self.skip
 184
 185             if command == 'help()':
 186                 self.appendPlainText("no help here!")
 187                 self.newPrompt()
 188                 return
 189
 190             sys.stdout = stdoutProxy(self.appendPlainText)
 191             try:
 192                 try:
 193                     result = eval(command, self.namespace, self.namespace)
 194                     if result != None:
 195                         if self.is_json:
 196                             util.print_json(result)
 197                         else:
 198                             self.appendPlainText(repr(result))
 199                 except SyntaxError:
 200                     exec command in self.namespace
 201             except SystemExit:
 202                 self.close()
 203             except:
 204                 traceback_lines = traceback.format_exc().split('\n')
 205                 # Remove traceback mentioning this file, and a linebreak
 206                 for i in (3,2,1,-1):
 207                     traceback_lines.pop(i)
 208                 self.appendPlainText('\n'.join(traceback_lines))
 209             sys.stdout = tmp_stdout
 210         self.newPrompt()
 211         self.set_json(False)
 212
 213
 214     def keyPressEvent(self, event):
 215         if event.key() == QtCore.Qt.Key_Tab:
 216             self.completions()
 217             return
 218
 219         self.hide_completions()
 220
 221         if event.key() in (QtCore.Qt.Key_Enter, QtCore.Qt.Key_Return):
 222             self.runCommand()
 223             return
 224         if event.key() == QtCore.Qt.Key_Home:
 225             self.setCursorPosition(0)
 226             return
 227         if event.key() == QtCore.Qt.Key_PageUp:
 228             return
 229         elif event.key() in (QtCore.Qt.Key_Left, QtCore.Qt.Key_Backspace):
 230             if self.getCursorPosition() == 0:
 231                 return
 232         elif event.key() == QtCore.Qt.Key_Up:
 233             self.setCommand(self.getPrevHistoryEntry())
 234             return
 235         elif event.key() == QtCore.Qt.Key_Down:
 236             self.setCommand(self.getNextHistoryEntry())
 237             return
 238         elif event.key() == QtCore.Qt.Key_L and event.modifiers() == QtCore.Qt.ControlModifier:
 239             self.clear()
 240
 241         super(Console, self).keyPressEvent(event)
 242
 243
 244
 245     def completions(self):
 246         cmd = self.getCommand()
 247         lastword = re.split(' |\(|\)',cmd)[-1]
 248         beginning = cmd[0:-len(lastword)]
 249
 250         path = lastword.split('.')
 251         ns = self.namespace.keys()
 252
 253         if len(path) == 1:
 254             ns = ns
 255             prefix = ''
 256         else:
 257             obj = self.namespace.get(path[0])
 258             prefix = path[0] + '.'
 259             ns = dir(obj)
 260
 261
 262         completions = []
 263         for x in ns:
 264             if x[0] == '_':continue
 265             xx = prefix + x
 266             if xx.startswith(lastword):
 267                 completions.append(xx)
 268         completions.sort()
 269
 270         if not completions:
 271             self.hide_completions()
 272         elif len(completions) == 1:
 273             self.hide_completions()
 274             self.setCommand(beginning + completions[0])
 275         else:
 276             # find common prefix
 277             p = os.path.commonprefix(completions)
 278             if len(p)>len(lastword):
 279                 self.hide_completions()
 280                 self.setCommand(beginning + p)
 281             else:
 282                 self.show_completions(completions)
 283
 284
 285 welcome_message = '''
 286    ---------------------------------------------------------------
 287      Welcome to a primitive Python interpreter.
 288    ---------------------------------------------------------------
 289 '''
 290
 291 if __name__ == '__main__':
 292     app = QtGui.QApplication(sys.argv)
 293     console = Console(startup_message=welcome_message)
 294     console.updateNamespace({'myVar1' : app, 'myVar2' : 1234})
 295     console.show();
 296     sys.exit(app.exec_())