From dc9e9db16047ec589a7b0488fac04c5bb682903c Mon Sep 17 00:00:00 2001
From: Josh Blum <josh@joshknows.com>
Date: Wed, 26 Aug 2009 13:29:28 -0700
Subject: [PATCH] added rewrite methods to element to separate from validation
 logic

---
 grc/base/Block.py     |  8 ++++++++
 grc/base/Element.py   |  4 +++-
 grc/base/FlowGraph.py | 11 ++++++++++-
 grc/gui/FlowGraph.py  |  6 ++----
 grc/python/Block.py   |  7 ++++++-
 grc/python/Port.py    | 14 ++++++++------
 6 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/grc/base/Block.py b/grc/base/Block.py
index 491c594c..d2266e78 100644
--- a/grc/base/Block.py
+++ b/grc/base/Block.py
@@ -140,6 +140,14 @@ class Block(Element):
 		"""
 		self.get_param('_enabled').set_value(str(enabled))
 
+	def rewrite(self):
+		"""
+		Rewrite critical structures.
+		Call rewrite on all sub elements.
+		"""
+		Element.rewrite(self)
+		for elem in self.get_ports() + self.get_params(): elem.rewrite()
+
 	def validate(self):
 		"""
 		Validate the block.
diff --git a/grc/base/Element.py b/grc/base/Element.py
index 16000c46..87cedb37 100644
--- a/grc/base/Element.py
+++ b/grc/base/Element.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008 Free Software Foundation, Inc.
+Copyright 2008, 2009 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -38,6 +38,8 @@ class Element(object):
 	def add_error_message(self, msg): self._error_messages.append(msg)
 	def get_error_messages(self): return self._error_messages
 
+	def rewrite(self): pass
+
 	def get_enabled(self): return True
 
 	def get_parent(self): return self._parent
diff --git a/grc/base/FlowGraph.py b/grc/base/FlowGraph.py
index fe493cce..990baf02 100644
--- a/grc/base/FlowGraph.py
+++ b/grc/base/FlowGraph.py
@@ -147,6 +147,14 @@ class FlowGraph(Element):
 		"""
 		raise NotImplementedError
 
+	def rewrite(self):
+		"""
+		Rewrite critical structures.
+		Call rewrite on all sub elements.
+		"""
+		Element.rewrite(self)
+		for elem in self.get_elements(): elem.rewrite()
+
 	def validate(self):
 		"""
 		Validate the flow graph.
@@ -198,7 +206,7 @@ class FlowGraph(Element):
 			#only load the block when the block key was valid
 			if block: block.import_data(block_n)
 			else: Messages.send_error_load('Block key "%s" not found in %s'%(key, self.get_parent()))
-		self.validate() #validate all blocks before connections are made (in case of nports)
+		self.rewrite() #rewrite all blocks before connections are made (ex: nports)
 		#build the connections
 		for connection_n in connections_n:
 			#try to make the connection
@@ -225,3 +233,4 @@ class FlowGraph(Element):
 				#build the connection
 				self.connect(source, sink)
 			except AssertionError: Messages.send_error_load('Connection between %s(%s) and %s(%s) could not be made.'%(source_block_id, source_key, sink_block_id, sink_key))
+		self.rewrite() #global rewrite
diff --git a/grc/gui/FlowGraph.py b/grc/gui/FlowGraph.py
index 007bb622..5e645be7 100644
--- a/grc/gui/FlowGraph.py
+++ b/grc/gui/FlowGraph.py
@@ -291,12 +291,10 @@ class FlowGraph(Element):
 
 	def update(self):
 		"""
+		Do a global rewrite and validate.
 		Call update on all elements.
-		Validate twice:
-		1) elements call special rewrite rules that may break validation
-		2) elements should come up with the same results, validation can pass
 		"""
-		self.validate()
+		self.rewrite()
 		self.validate()
 		for element in self.get_elements(): element.update()
 
diff --git a/grc/python/Block.py b/grc/python/Block.py
index 47fe13a3..f47f7644 100644
--- a/grc/python/Block.py
+++ b/grc/python/Block.py
@@ -54,7 +54,6 @@ class Block(_Block):
 		Validate this block.
 		Call the base class validate.
 		Evaluate the checks: each check must evaluate to True.
-		Adjust the nports.
 		"""
 		_Block.validate(self)
 		#evaluate the checks
@@ -65,6 +64,12 @@ class Block(_Block):
 				try: assert check_eval
 				except AssertionError: self.add_error_message('Check "%s" failed.'%check)
 			except: self.add_error_message('Check "%s" did not evaluate.'%check)
+
+	def rewrite(self):
+		"""
+		Add and remove ports to adjust for the nports.
+		"""
+		_Block.rewrite(self)
 		#adjust nports
 		for get_ports, get_port in (
 			(self.get_sources, self.get_source),
diff --git a/grc/python/Port.py b/grc/python/Port.py
index bfbac723..dde736db 100644
--- a/grc/python/Port.py
+++ b/grc/python/Port.py
@@ -57,17 +57,19 @@ class Port(_Port):
 		except AssertionError: self.add_error_message('Port is not connected.')
 		try: assert self.is_source() or len(self.get_enabled_connections()) <= 1
 		except AssertionError: self.add_error_message('Port has too many connections.')
-		################################################################
-		# message port logic
-		################################################################
+		#message port logic
 		if self.get_type() == 'msg':
 			try: assert not self.get_nports()
 			except AssertionError: self.add_error_message('A port of type "msg" cannot have "nports" set.')
 			try: assert self.get_vlen() == 1
 			except AssertionError: self.add_error_message('A port of type "msg" must have a "vlen" of 1.')
-		################################################################
-		# virtual sink logic
-		################################################################
+
+	def rewrite(self):
+		"""
+		Handle the port cloning for virtual blocks.
+		"""
+		_Port.rewrite(self)
+		#virtual sink logic
 		if self.get_parent().get_key() == 'virtual_sink':
 			if self.get_enabled_connections(): #clone type and vlen
 				source = self.get_enabled_connections()[0].get_source()
-- 
2.30.2