Something

#!/usr/bin/python

"""Qt shared textpad.

synchronizes the text  betweens server and clients.
"""

import sys, urlparse
from qt import *

from twisted.protocols.basic import LineReceiver

from twisted.internet import protocol
import qtreactor

from sharedtextCommon import * 

app = QApplication([])
qtreactor.install(app)

class QobbyClientFactory(protocol.ClientFactory):
    def __init__(self, qwin):
        self.qwin = qwin
        print "Client factory created"

    def buildProtocol(self, addr):
        print "Client Protocol built"
        p = QobbyClient(self.qwin)
        p.factory = self
        return p


class QobbyClient(LineReceiver):
    def __init__(self, qwin):
        print "Protocol __init__ed"
        self.qwin = qwin
        app.connect(self.qwin.edit, PYSIGNAL("Changed"), self.keyPress)
        self.op_number = 0

    def connectionMade(self):
        print 'Connected to server'
        
    def lineReceived(self, line):
        if len(line)!=0:
            if self.connected:
                if line.count('~') == 3:
                    op_number, cursor_line, cursor_char, new_char = line.split("~")
                    op_number = int(op_number)
                    cursor_line = int(cursor_line)
                    cursor_char = int(cursor_char)
                    new_char = chr(int(new_char))
                    
                    print "Received:", op_number, cursor_line, cursor_char, new_char
                    cursor_line_old, cursor_char_old = self.qwin.edit. getCursorPosition()
                    
                    if new_char == '\x08': # backspace
                        self.qwin.edit.setCursorPosition(cursor_line, cursor_char)
                        self.qwin.edit.delChar()
                    elif new_char == '\x7f': # del
                        self.qwin.edit.setCursorPosition(cursor_line, cursor_char)
                        self.qwin.edit.delChar()
                    elif new_char == '\r': # CRl
                        self.qwin.edit.setCursorPosition(cursor_line, cursor_char)
                        self.qwin.edit.insertParagraph("",cursor_line)
                    else:
                        self.qwin.edit.setCursorPosition(cursor_line, cursor_char-1)
                        self.qwin.edit.insert(new_char)
                    self.qwin.edit.setCursorPosition(cursor_line_old, cursor_char_old)
            elif line == "WELCOME-QOBBY":
                self.connected = True

    def keyPress(self, (cursor_line, cursor_char), new_char):
        #Command format:
        #OperationNumber~CursorLine~CursorChar~Chars
        self.sendLine(str(self.op_number) + '~' + str(cursor_line) + '~' +\
        str(cursor_char) + '~' + str(new_char))

class TwistzillaWindow(QMainWindow):
    def __init__(self, *args):
        QMainWindow.__init__(self, *args)

        self.setCaption("Qobby :-)")

        vbox = QVBox(self)
        vbox.setMargin(2)
        vbox.setSpacing(3)

        hbox = QHBox(vbox)
        label = QLabel("Client. Write here: ", hbox)

        self.edit = MyQTextEdit(vbox)
        #self.edit.setEdited(0)
        #self.connect(self.edit, SIGNAL('textChanged()'), self.updateText)
        self.connect(self.edit, PYSIGNAL('Changed'), self.updateText)

        self.setCentralWidget(vbox)

        self.connectToServer("127.0.0.1",6666)

    def updateText(self, a, b):
        print a
        print b
        print "text is:", self.edit.text()

    def connectToServer(self, host, port):
        print 'Connecting to:', host, port
        from twisted.internet import reactor
        factory = QobbyClientFactory(self)
        reactor.connectTCP(host, port, factory)

def main():
    """Run application."""
    # hook up Qt application to Twisted
    from twisted.internet import reactor
    
    win = TwistzillaWindow()
    win.show()

    # make sure stopping twisted event also shuts down QT
    reactor.addSystemEventTrigger('after', 'shutdown', app.quit )

    # shutdown twisted when window is closed
    app.connect(app, SIGNAL("lastWindowClosed()"), reactor.stop)

    reactor.run()


if __name__ == '__main__':
    main()