vtkmethodparser.py

a very goog book

"""
This python module provides functionality to parse the methods of a
VTK object.

Created by Prabhu Ramachandran.  Committed in Apr, 2002.

"""

import string, re, sys
import types

# set this to 1 if you want to see debugging messages - very useful if
# you have problems
DEBUG=0

def debug (msg):
    if DEBUG:
	print msg

class VtkDirMethodParser:
    """ Parses the methods from dir(vtk_obj). """
    def initialize_methods (self, vtk_obj):
        debug ("VtkDirMethodParser:: initialize_methods ()")

	self.methods = dir (vtk_obj)[:]
	# stores the <blah>On methods
	self.toggle_meths = []
	# stores the Set<blah>To<blah> methods
	self.state_meths = []
	# stores the methods that have a Get<blah> and Set<blah>
	# only the <blah> is stored
	self.get_set_meths = []
	# pure get methods
	self.get_meths = []
	self.state_patn = re.compile ("To[A-Z0-9]")

    def parse_methods (self, vtk_obj):
	debug ("VtkDirMethodParser:: parse_methods()")
        self.initialize_methods (vtk_obj)	
	debug ("VtkDirMethodParser:: parse_methods() - initialized methods")
	
	for method in self.methods[:]:
	    # finding all the methods that set the state.
	    if string.find (method[:3], "Set") >= 0 and \
		 self.state_patn.search (method) is not None :
                try:
                    eval ("vtk_obj.Get%s"%method[3:])
                except AttributeError:
                    self.state_meths.append (method)
                    self.methods.remove (method)
            # finding all the On/Off toggle methods
	    elif string.find (method[-2:], "On") >= 0:
                try:
                    self.methods.index ("%sOff"%method[:-2])
                except ValueError:
                    pass
                else:
                    self.toggle_meths.append (method)
                    self.methods.remove (method)
                    self.methods.remove ("%sOff"%method[:-2])            
	    # finding the Get/Set methods.
	    elif string.find (method[:3], "Get") == 0:
		set_m = "Set"+method[3:]
		try: 
		    self.methods.index (set_m) 
		except ValueError:
		    pass
		else:
		    self.get_set_meths.append (method[3:])
		    self.methods.remove (method)
		    self.methods.remove (set_m)

	self.clean_up_methods (vtk_obj)

    def clean_up_methods (self, vtk_obj):
	self.clean_get_set (vtk_obj)
	self.clean_state_methods (vtk_obj)
	self.clean_get_methods (vtk_obj)

    def clean_get_set (self, vtk_obj):
	debug ("VtkDirMethodParser:: clean_get_set()")
	# cleaning up the Get/Set methods by removing the toggle funcs.
	for method in self.toggle_meths:
	    try:
		self.get_set_meths.remove (method[:-2])
	    except ValueError:
		pass

	# cleaning them up by removing any methods that are responsible for
	# other vtkObjects
	for method in self.get_set_meths[:]:
	    try:
		eval ("vtk_obj.Get%s ().GetClassName ()"%method)
	    except (TypeError, AttributeError):
		pass
	    else:
		self.get_set_meths.remove (method)
                continue
	    try:
		val = eval ("vtk_obj.Get%s ()"%method)
	    except (TypeError, AttributeError):
		self.get_set_meths.remove (method)
	    else:
		if val is None:
		    self.get_set_meths.remove (method)
	
    def clean_state_methods (self, vtk_obj):
	debug ("VtkDirMethodParser:: clean_state_methods()")
	# Getting the remaining pure GetMethods 
	for method in self.methods[:]:
	    if string.find (method[:3], "Get") == 0:
		self.get_meths.append (method)
		self.methods.remove (method)

	# Grouping similar state methods
	if len (self.state_meths) != 0:
	    tmp = self.state_meths[:]
	    self.state_meths = []
	    state_group = [tmp[0]]
	    end = self.state_patn.search (tmp[0]).start ()
	    # stores the method type common to all similar methods
	    m = tmp[0][3:end] 
	    for i in range (1, len (tmp)):
		if string.find (tmp[i], m) >= 0:
		    state_group.append (tmp[i])
		else:
		    self.state_meths.append (state_group)
		    state_group = [tmp[i]]	
		    end = self.state_patn.search (tmp[i]).start ()
		    m = tmp[i][3:end]
		try: # remove the corresponding set method in get_set
		    val = self.get_set_meths.index (m)
		except ValueError: 
		    pass
		else:
		    del self.get_set_meths[val]
		    #self.get_meths.append ("Get"+m)
                clamp_m = "Get" + m + "MinValue"
                try: # remove the GetNameMax/MinValue in get_meths
                    val = self.get_meths.index (clamp_m)
                except ValueError:
                    pass
                else:
                    del self.get_meths[val]
                    val = self.get_meths.index ("Get" + m + "MaxValue")
                    del self.get_meths[val]

	    if len (state_group) > 0:
		self.state_meths.append (state_group)

    def clean_get_methods (self, vtk_obj):
	debug ("VtkDirMethodParser:: clean_get_methods()")
	for method in self.get_meths[:]:
            debug (method)
            try:
		res = eval ("vtk_obj.%s ()"%method)
	    except (TypeError, AttributeError):
		self.get_meths.remove (method)
                continue
	    else:
		try:
		    eval ("vtk_obj.%s ().GetClassName ()"%method)
		except AttributeError:
		    pass
		else:
		    self.get_meths.remove (method)
                    continue
            if string.find (method[-8:], "MaxValue") > -1:
                self.get_meths.remove( method)
            elif string.find (method[-8:], "MinValue") > -1:
                self.get_meths.remove( method)
                
	self.get_meths.sort ()

    def toggle_methods (self):
	return self.toggle_meths

    def state_methods (self):
	return self.state_meths

    def get_set_methods (self):
	return self.get_set_meths

    def get_methods (self):
	return self.get_meths


class VtkPrintMethodParser:

    """ This class finds the methods for a given vtkObject.  It uses
    the output from vtkObject->Print() (or in Python str(vtkObject))
    and output from the VtkDirMethodParser to obtain the methods. """
    
    def parse_methods (self, vtk_obj):
	"Parse for the methods."
	debug ("VtkPrintMethodParser:: parse_methods()")

        if self._initialize_methods (vtk_obj):
            # if David Gobbi's improvements are in this version of VTK
            # then I need to go no further.
            return

	for method in self.methods[:]:
	    # removing methods that have nothing to the right of the ':'
	    if (method[1] == '') or \
	       (string.find (method[1], "none") > -1) :
		self.methods.remove (method)

	for method in self.methods:
	    # toggle methods are first identified
	    if (method[1] == "On") or (method[1] == "Off"):
		try:
		    val = eval ("vtk_obj.Get%s ()"%method[0])
		    if val == 1:
			eval ("vtk_obj.%sOn ()"%method[0])
		    elif val == 0:
			eval ("vtk_obj.%sOff ()"%method[0])
		except AttributeError:
		    pass
		else:
		    self.toggle_meths.append (method[0]+"On")		
	    else: # see it it is get_set or get or a state method
		found = 0
		# checking if it is a state func.
		# figure out the long names from the dir_state_meths
		for sms in self.dir_state_meths[:]:
		    if string.find (sms[0], method[0]) >= 0:
			self.state_meths.append (sms)
			self.dir_state_meths.remove (sms)
			found = 1
		if found:
		    self.get_meths.append ("Get"+method[0])
		    try:
			t = eval ("vtk_obj.Get%sAsString ()"%method[0])
		    except AttributeError:
			pass
		    else:
			self.get_meths.append ("Get"+method[0]+"AsString")
		else: 
		    # the long name is inherited or it is not a state method
		    try:
			t = eval ("vtk_obj.Get%s ().GetClassName ()"%
				  method[0])
		    except AttributeError:
			pass
		    else:
			continue	
		    val = 0
		    try:
			val = eval ("vtk_obj.Get%s ()"%method[0])
		    except (TypeError, AttributeError):
			pass
		    else:
                        try:
                            f = eval ("vtk_obj.Set%s"%method[0])
                        except AttributeError:
                            self.get_meths.append ("Get"+method[0])
                        else:
                            try:
                                apply (f, val)
                            except TypeError:
                                try:
                                    apply (f, (val, ))
                                except TypeError:
                                    self.get_meths.append ("Get"+method[0])
                                else:
                                    self.get_set_meths.append (method[0])
                            else:
                                self.get_set_meths.append (method[0])
                        
        self._clean_up_methods (vtk_obj)

    def _get_str_obj (self, vtk_obj):
	debug ("VtkPrintMethodParser:: _get_str_obj()")
	self.methods = str (vtk_obj)
	self.methods = string.split (self.methods, "\n")
	del self.methods[0]

    def _initialize_methods (self, vtk_obj):
	"Do the basic parsing and setting up"
	debug ("VtkPrintMethodParser:: _initialize_methods()")
	dir_p = VtkDirMethodParser ()
	dir_p.parse_methods (vtk_obj)

        # testing if this version of vtk has David Gobbi's cool
        # stuff. If it does then no need to do other things.
        try:
            junk = vtk_obj.__class__
        except AttributeError:
            pass
        else:
            self.toggle_meths = dir_p.toggle_methods ()
            self.state_meths = dir_p.state_methods ()
            self.get_set_meths = dir_p.get_set_methods ()
            self.get_meths = dir_p.get_methods ()
            return 1

	self.dir_toggle_meths = dir_p.toggle_methods ()
	self.dir_state_meths = dir_p.state_methods ()
	self.dir_get_set_meths = dir_p.get_set_methods ()
	self.dir_get_meths = dir_p.get_methods ()

	self._get_str_obj (vtk_obj)
	patn = re.compile ("  \S")
    
	for method in self.methods[:]:
	    if not patn.match (method):
		self.methods.remove (method)
    
	for method in self.methods[:]:
	    if string.find (method, ":") == -1:
		self.methods.remove (method)

	for i in range (0, len (self.methods)):
	    strng = self.methods[i]
	    strng = string.replace (strng, " ", "")
	    self.methods[i] = string.split (strng, ":")


	self.toggle_meths = []
	self.state_meths = []
	self.get_set_meths = []
	self.get_meths = []    

        return 0

    def _clean_up_methods (self, vtk_obj):
	"Merge dir and str methods.  Finish up."
	debug ("VtkPrintMethodParser:: _clean_up_methods()")
	for meth_list in ((self.dir_toggle_meths, self.toggle_meths),\
			  (self.dir_get_set_meths, self.get_set_meths),\
			  (self.dir_get_meths, self.get_meths)):
	    for method in meth_list[0]:
		try:
		    meth_list[1].index (method)
		except ValueError:
		    meth_list[1].append (method)	    

	# Remove all get_set methods that are already in toggle_meths
	# This case can happen if the str produces no "On/Off" but
	# dir does and str produces a get_set instead.
	for method in self.toggle_meths:
	    try:
		self.get_set_meths.remove (method[:-2])
	    except ValueError:
		pass

	self.toggle_meths.sort ()
	self.state_meths.sort ()
	self.get_set_meths.sort ()
	self.get_meths.sort ()
    
    def toggle_methods (self):
	return self.toggle_meths

    def state_methods (self):
	return self.state_meths

    def get_set_methods (self):
	return self.get_set_meths

    def get_methods (self):
	return self.get_meths