MiniAEFrame.py

"""MiniAEFrame - A minimal AppleEvent Application framework.

There are two classes:
    AEServer -- a mixin class offering nice AE handling.
    MiniApplication -- a very minimal alternative to FrameWork.py,
        only suitable for the simplest of AppleEvent servers.
"""

import sys
import traceback
import MacOS
from Carbon import AE
from Carbon.AppleEvents import *
from Carbon import Evt
from Carbon.Events import *
from Carbon import Menu
from Carbon import Win
from Carbon.Windows import *
from Carbon import Qd

import aetools
import EasyDialogs

kHighLevelEvent = 23                # Not defined anywhere for Python yet?


class MiniApplication:

    """A minimal FrameWork.Application-like class"""

    def __init__(self):
        self.quitting = 0
        # Initialize menu
        self.appleid = 1
        self.quitid = 2
        Menu.ClearMenuBar()
        self.applemenu = applemenu = Menu.NewMenu(self.appleid, "\024")
        applemenu.AppendMenu("%s;(-" % self.getaboutmenutext())
        if MacOS.runtimemodel == 'ppc':
            applemenu.AppendResMenu('DRVR')
        applemenu.InsertMenu(0)
        self.quitmenu = Menu.NewMenu(self.quitid, "File")
        self.quitmenu.AppendMenu("Quit")
        self.quitmenu.SetItemCmd(1, ord("Q"))
        self.quitmenu.InsertMenu(0)
        Menu.DrawMenuBar()

    def __del__(self):
        self.close()

    def close(self):
        pass

    def mainloop(self, mask = everyEvent, timeout = 60*60):
        while not self.quitting:
            self.dooneevent(mask, timeout)

    def _quit(self):
        self.quitting = 1

    def dooneevent(self, mask = everyEvent, timeout = 60*60):
        got, event = Evt.WaitNextEvent(mask, timeout)
        if got:
            self.lowlevelhandler(event)

    def lowlevelhandler(self, event):
        what, message, when, where, modifiers = event
        h, v = where
        if what == kHighLevelEvent:
            msg = "High Level Event: %r %r" % (code(message), code(h | (v<<16)))
            try:
                AE.AEProcessAppleEvent(event)
            except AE.Error, err:
                print 'AE error: ', err
                print 'in', msg
                traceback.print_exc()
            return
        elif what == keyDown:
            c = chr(message & charCodeMask)
            if modifiers & cmdKey:
                if c == '.':
                    raise KeyboardInterrupt, "Command-period"
                if c == 'q':
                    if hasattr(MacOS, 'OutputSeen'):
                        MacOS.OutputSeen()
                    self.quitting = 1
                    return
        elif what == mouseDown:
            partcode, window = Win.FindWindow(where)
            if partcode == inMenuBar:
                result = Menu.MenuSelect(where)
                id = (result>>16) & 0xffff      # Hi word
                item = result & 0xffff      # Lo word
                if id == self.appleid:
                    if item == 1:
                        EasyDialogs.Message(self.getabouttext())
                    elif item > 1 and hasattr(Menu, 'OpenDeskAcc'):
                        name = self.applemenu.GetMenuItemText(item)
                        Menu.OpenDeskAcc(name)
                elif id == self.quitid and item == 1:
                    if hasattr(MacOS, 'OutputSeen'):
                        MacOS.OutputSeen()
                    self.quitting = 1
                Menu.HiliteMenu(0)
                return
        # Anything not handled is passed to Python/SIOUX
        if hasattr(MacOS, 'HandleEvent'):
            MacOS.HandleEvent(event)
        else:
            print "Unhandled event:", event

    def getabouttext(self):
        return self.__class__.__name__

    def getaboutmenutext(self):
        return "About %s\311" % self.__class__.__name__


class AEServer:

    def __init__(self):
        self.ae_handlers = {}

    def installaehandler(self, classe, type, callback):
        AE.AEInstallEventHandler(classe, type, self.callback_wrapper)
        self.ae_handlers[(classe, type)] = callback

    def close(self):
        for classe, type in self.ae_handlers.keys():
            AE.AERemoveEventHandler(classe, type)

    def callback_wrapper(self, _request, _reply):
        _parameters, _attributes = aetools.unpackevent(_request)
        _class = _attributes['evcl'].type
        _type = _attributes['evid'].type

        if self.ae_handlers.has_key((_class, _type)):
            _function = self.ae_handlers[(_class, _type)]
        elif self.ae_handlers.has_key((_class, '****')):
            _function = self.ae_handlers[(_class, '****')]
        elif self.ae_handlers.has_key(('****', '****')):
            _function = self.ae_handlers[('****', '****')]
        else:
            raise 'Cannot happen: AE callback without handler', (_class, _type)

        # XXXX Do key-to-name mapping here

        _parameters['_attributes'] = _attributes
        _parameters['_class'] = _class
        _parameters['_type'] = _type
        if _parameters.has_key('----'):
            _object = _parameters['----']
            del _parameters['----']
            # The try/except that used to be here can mask programmer errors.
            # Let the program crash, the programmer can always add a **args
            # to the formal parameter list.
            rv = _function(_object, **_parameters)
        else:
            #Same try/except comment as above
            rv = _function(**_parameters)

        if rv == None:
            aetools.packevent(_reply, {})
        else:
            aetools.packevent(_reply, {'----':rv})


def code(x):
    "Convert a long int to the 4-character code it really is"
    s = ''
    for i in range(4):
        x, c = divmod(x, 256)
        s = chr(c) + s
    return s

class _Test(AEServer, MiniApplication):
    """Mini test application, handles required events"""

    def __init__(self):
        MiniApplication.__init__(self)
        AEServer.__init__(self)
        self.installaehandler('aevt', 'oapp', self.open_app)
        self.installaehandler('aevt', 'quit', self.quit)
        self.installaehandler('****', '****', self.other)
        self.mainloop()

    def quit(self, **args):
        self._quit()

    def open_app(self, **args):
        pass

    def other(self, _object=None, _class=None, _type=None, **args):
        print 'AppleEvent', (_class, _type), 'for', _object, 'Other args:', args


if __name__ == '__main__':
    _Test()