cpython/Lib/plat-mac/argvemulator.py

"""argvemulator - create sys.argv from OSA events. Used by applets that
want unix-style arguments.
"""

import sys
import traceback
from Carbon import AE
from Carbon.AppleEvents import *
from Carbon import Evt
from Carbon.Events import *
import aetools

class ArgvCollector:
	
	"""A minimal FrameWork.Application-like class"""
	
	def __init__(self):
		self.quitting = 0
		self.ae_handlers = {}
		# Remove the funny -psn_xxx_xxx argument
		if len(sys.argv) > 1 and sys.argv[1][:4] == '-psn':
			del sys.argv[1]
		self.installaehandler('aevt', 'oapp', self.open_app)
		self.installaehandler('aevt', 'odoc', self.open_file)
	
	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 mainloop(self, mask = highLevelEventMask, timeout = 1*60):
		stoptime = Evt.TickCount() + timeout
		while not self.quitting and Evt.TickCount() < stoptime:
			self.dooneevent(mask, timeout)
		self.close()
	
	def _quit(self):
		self.quitting = 1
	
	def dooneevent(self, mask = highLevelEventMask, timeout = 1*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:
			try:
				AE.AEProcessAppleEvent(event)
			except AE.Error, err:
				msg = "High Level Event: %s %s" % \
					(`hex(message)`, `hex(h | (v<<16))`)
				print 'AE error: ', err
				print 'in', msg
				traceback.print_exc()
			return
		else:
			print "Unhandled event:", event

	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 = apply(_function, (_object,), _parameters)
		else:
			#Same try/except comment as above
			rv = apply(_function, (), _parameters)
		
		if rv == None:
			aetools.packevent(_reply, {})
		else:
			aetools.packevent(_reply, {'----':rv})

	def open_app(self, **args):
		self._quit()
		
	def open_file(self, _object=None, **args):
		for alias in _object:
			fsr = alias.FSResolveAlias(None)[0]
			pathname = fsr.as_pathname()
			sys.argv.append(pathname)
		self._quit()
		
	def other(self, _object=None, _class=None, _type=None, **args):
		print 'Ignore AppleEvent', (_class, _type), 'for', _object, 'Other args:', args

if __name__ == '__main__':
	ArgvCollector().mainloop()
	print "sys.argv=", sys.argv