class Sandbox(object):
	# DO NOT REMOVE ANY ENTRY OF WHITE LIST
	# THIS ENTIES ARE USED FOR Sandbox.
	# 	(If sys.modules['__main__'] is changed, you can see the hell.)
	WHITE_LIST = ['__builtin__', 'types', __name__, '__main__', 'sys']
	def __init__(self, prevent_imported_modules = False, allowed_modules = [], prevented_modules = [], allowed_paths = []):
		self.prevent_imported_modules = prevent_imported_modules
		self.allowed_modules = allowed_modules
		self.prevented_modules = prevented_modules
		self.allowed_paths = allowed_paths

	def add_allowed_modules(self, allowed_modules):
		self.allowed_modules = self.allowed_modules + allowed_modules

	def add_prevented_modules(self, prevented_modules):
		self.prevented_modules = self.prevented_modules + prevented_modules

	def execfile(self, filename, dic):
		import sys
		import copy

		for allowed_module_name in self.allowed_modules:
			try:
				exec 'import {0}'.format(allowed_module_name)
			except:
				# Just now, pass the exception.
				# (filename could not use this module)
				sys.modules['dbg'].TraceError("UISCRIPT_LOAD_ERROR: Could not import %s [filename %s]" % (allowed_module_name, filename)) # @fixme004 (sys.stderr.write to dbg.TraceError)
				pass
		# shallow copy of sys.modules
		old_modules = copy.copy(sys.modules)

		old_path = sys.path
		sys.path = self.allowed_paths

		# set current imported modules None
		if self.prevent_imported_modules:
			import types
			for k, v in old_modules.items():
				if type(v) == types.ModuleType:
					if not (k in self.WHITE_LIST or k in self.allowed_modules):
						sys.modules[k] = None

		# set prevented modules None.
		for prevented_module_name in self.prevented_modules:
			sys.modules[prevented_module_name] = None

		try:
			f = open(filename, 'rb')
			data = f.read()
			code = compile(data, filename, 'exec')
			exec code in dic
		except Exception as e:
			old_modules['dbg'].TraceError("UISCRIPT_LOAD_ERROR: %s [filename %s]" % (str(e), filename)) # @fixme004 (sys.stderr.write to dbg.TraceError)
		finally:
			# Restore original settings.
			#sys.modules = old_modules# <- This is not effective. I don't know why, but I guess some where got old sys.modules reference and access old one.
			for k, v in sys.modules.items():
				if not k in old_modules:
					del sys.modules[k]
			for k, v in old_modules.items():
				sys.modules[k] = v

			sys.path = old_path

#######################################################
#	@usage:
#		GetElementDictByName(window,"BoardExample")
#
#	@desc:
#		it could search in a dict (script file for ScriptWindow) an element (whether it is child of window or another child in the tree)
#
#	@notes:
#		adviced to check the return before to access (it could be None)
def GetElementDictByName(dct, name):
	if 'children' in dct:
		for child in dct['children']:
			if 'name' in child:
				if child['name'] == name:
					return child

			if 'children' in child:
				search = GetElementDictByName(child, name)
				if search != None:
					return search
	return None

### Find the element <name> inside <parent> and return the pos
def FindElementPos(parent, name):
	for i in range(len(parent)):
		if parent[i]["name"] == name:
			return i
	return -1

### Find the element <name> inside <parent> and return the ref
def FindElementRef(parent, name):
	for i in range(len(parent)):
		if parent[i]["name"] == name:
			return parent[i]
	return None

### Find the element <name> inside <parent> and add it before that (only for lists)
def ElementAddBefore(parent, name, obj):
	i = FindElementPos(parent, name)
	if i != -1:
		parent.insert(i, obj)

### Find the element <name> inside <parent> and add it after that (only for lists)
def ElementAddAfter(parent, name, obj):
	i = FindElementPos(parent, name)
	if i != -1:
		parent.insert(i+1, obj)

def FindElement(name, data):
	if 'children' in data:
		for child in data['children']:
			if child.get('name', '') == name:
				return child
		for child in data['children']:
			res = FindElement(name, child)
			if res:
				return res
	return None

def ReplaceElement(name, nvalue, data):
	value = FindElement(name, data)
	for n, v in nvalue.items():
		value[n] = v
	for n in value:
		if n not in nvalue:
			del value[n]

def AppendChildren(name, children, data):
	value = FindElement(name, data)
	value['children'] = value.get('children', tuple()) + children