#!/usr/bin/python
# LocalVarToAuto.py
# Change the class name in local variable assignment to auto
# Copyright (c) 2013 cocos2d-x.org
# Author: YuBo

# This script is used for change the class name in local variable assignment to auto.
# Right now there is some poblems you might want notice:
# To start we will assume we has a class A.
# 
# 1. If you have classes like this:
# class B : public A{}; 
# class C : public A{};
# And you write code like this:
# A* b = a_bclass_ptr;
# C* c = new C();
# ...
# b = c;
# We will change it to:
# auto b = a_bclass_ptr;
# auto c = new C();
# It will cause a compile error because you assign pointer with type C to different pointer
# with type B. You must edit it manually.
#
# 2. If your function has default params with class A, we will change it to auto you might
# unexpected. For example:
# void f(A* a = new A()){} or void f(A a = A()){}
#
# 3. If you have define macro like this:
# #define ANOTHER_A_NAME A
# and use it like this:
# ANOTHER_A_NAME* a = new A();
# We will not convert it to auto for you.

import os.path
import re
import types
import fileinput
import cStringIO

# The cocos root entry. We will aspect it as parent dictionary, all other file or dictionary
# relative path are base on this.
COCOS_ROOT = "../../"
# The class declaration dictionaries, we will search the class declaration with .h files in it.
H_DIR = ("cocos2dx", "CocosDenshion", "extensions")
# The src files you want to edit, we will search the .cpp and .mm files in it.
CXX_DIR = ("Samples",)
# The dictionaries and files with class declaration you don't want to search, you can exclude some third party
# dictionaries in here
EXCLUDE = ("cocos2dx/platform/third_party/",)
# The extra dictionaries and files with class declaration. You can add some extra .h files in it
INCLUDE = ()
# The macroes use with declare class, like "class CC_DLL A{}"
MACROES_WITH_CLASS = ("CC_DLL",)
# The strings represent the null pointer, because you set a point to null, we will not change that
# variable to auto.
NULL_PTR = ("0", "NULL", "nullptr")

# normalize the path
COCOS_ROOT = os.path.abspath(COCOS_ROOT)

def check_file_match_rep(repString, filePath):
	'''Check the file with filepath is match the repstring or not.
	Return True if match, return False if not.
	NOTE: it will check the EXCLUDE files and directories, if the file is in the EXCLUDE directories
	or is a EXCLUDE file, it will return False.'''

	#normalize the path
	realFilePath = os.path.abspath(filePath)

	if not os.path.isfile(realFilePath):
		return False

	rep = re.compile(repString)
	curDir, fileName = os.path.split(realFilePath)

	# check dir is exclude or not
	for dir in EXCLUDE:
		dir = os.path.abspath(os.path.join(COCOS_ROOT, dir))
		if os.path.isdir(dir) and os.path.isdir(curDir[:len(dir)]):
			if os.path.samefile(dir, curDir[:len(dir)]):
				return False
	
	if rep.match(fileName):
		# check file is exclude or not
		for file in EXCLUDE:
			if os.path.isfile(os.path.join(COCOS_ROOT, file)):
				if os.path.samefile(realFilePath, os.path.join(COCOS_ROOT, file)):
					return False

		return True

	return False

def walk_collect_h_files(lst, dirname, names):
	"collect *.h files and insert into lst"

	for name in names:
		if check_file_match_rep(".*\.h$", os.path.join(dirname, name)):
			if type(lst) is types.ListType:
				lst += [os.path.relpath(os.path.abspath(os.path.join(dirname, name)), COCOS_ROOT)]

def walk_collect_cxx_files(lst, dirname, names):
	"collect *.cpp and *.mm files and insert into lst"

	for name in names:
		if check_file_match_rep(".*\.(?:cpp)|(?:mm)$", os.path.join(dirname, name)):
			if type(lst) is types.ListType:
				lst += [os.path.relpath(os.path.abspath(os.path.join(dirname, name)), COCOS_ROOT)]

def collect_class_name(filename, st):
	"collect all class name appear in the file"
	
	#generate the rep
	if not hasattr(collect_class_name, "rep"):
		repString = cStringIO.StringIO()
		repString.write("(?:\s+|^)class\s+")
		for word in MACROES_WITH_CLASS:
			repString.write(word + "\s+")
		repString.write("(?P<cls_name>\w+)")

		collect_class_name.rep = re.compile(repString.getvalue())
		repString.close()
	
	f = open(os.path.join(COCOS_ROOT, filename))
	try:
		for line in f:
			res = collect_class_name.rep.match(line)
			if res: 
				if type(st) == type(set()):
					st.add(res.group("cls_name"))
	finally:
		f.close()

def change_local_classvarname_to_auto(filename, rep, change):
	"change all local class variable name to auto"
	f = open(filename)
	
	content = None
	changed = False
	# read the file, change it, and save it to content
	try:
		content = cStringIO.StringIO()
		changed = False
		
		for line in f:
			i = 0
			#start to replace
			while True:
				result = rep.match(line, i)
				# founded
				if result:
					changed = True
					#find the matched string where to start
					startIndex = line.index(result.group(0))
					#replace the change part
					line = line.replace(result.group(change), "auto ", startIndex)
					i += 1
				else:
					break
			#write the result to content
			content.write(line)
	finally:
		f.close()
		if changed:
			f = open(filename, "w")
			f.write(content.getvalue())
			f.close()
		content.close()

def main():

	print ".......VARIABLES......."
	print "COCOS_ROOT:", 
	print COCOS_ROOT
	print "H_DIR:",
	print H_DIR
	print "CXX_DIR:",
	print CXX_DIR
	print "EXCLUDE:",
	print EXCLUDE
	print "INCLUDE:",
	print INCLUDE
	print ".......VARIABLES END......"
	
	# save the .h file for search
	hfiles = []
	# save the .cpp and .mm file for search
	cxxfiles = []
	
	print "search .h files..."
	for dir in H_DIR:
		os.path.walk(os.path.join(COCOS_ROOT, dir), walk_collect_h_files, hfiles)
	
	for dir in INCLUDE:
		if os.path.isdir(os.path.join(COCOS_ROOT, dir)):
			os.path.walk(os.path.join(COCOS_ROOT, dir), walk_collect_h_files, hfiles)
		else:
			hfiles += [dir]
	print "search end"

	print "search .cxx files..."
	for dir in CXX_DIR:
		os.path.walk(os.path.join(COCOS_ROOT, dir), walk_collect_cxx_files, cxxfiles)
	print "search end"

	print "search class declarations"
	# the class set, ignore the namespace
	classes = set()
	for file in hfiles:
		collect_class_name(file, classes)
	print "search end"

	# generate example rep:
	# (\W+|^)(?P<keyWord>\S*(?:Class1|Class2|class3)\s*(?:\*+|\s+)\s*)\w+\s*=(?!\s*(?:0|NULL|nullptr)\s*\W)
	# examples:
	# Class1* c = new Class1() ; //match
	# Class1* c;                 //not match
	# Class1* c = nullptr;       //not match
	# Class1* c = nullptrabc;    //match
	# Class1 c;                  //not match
	# Class1 c = Class1();       //match
	def gen_rep(keyWord):
		s = cStringIO.StringIO()
		s.write("(?:\W+|^)(?P<")
		s.write(keyWord)
		s.write(">\S*(?:")
		
		# add classes want to match
		first = True
		for cls in classes:
			if first:
				first = False
			else:
				s.write("|")

			s.write(cls)
		
		s.write(")\s*(?:\*+|\s+)\s*)\w+\s*=(?!\s*(?:")

		# let nullptr assignment not to convert
		first = True
		for nullptr in NULL_PTR:
			if first:
				first = False
			else:
				s.write("|")

			s.write(nullptr)

		s.write(")\s*\W)")

		result = s.getvalue()
		s.close()

		print "generated regular expression is:"
		print result
		return re.compile(result)
	
	repWord = "change"
	rep = gen_rep(repWord)


	print "scan and edit the .cxx files..."
	# scan the cxx files
	for file in cxxfiles:
		change_local_classvarname_to_auto(os.path.join(COCOS_ROOT, file), rep, repWord)
 	
	print "success!"
	

if __name__ == "__main__":
	main()