#!/usr/bin/env python

# Copyright (c) 2007-2008 Pedro Matiello <pmatiello@gmail.com>

#

# Permission is hereby granted, free of charge, to any person

# obtaining a copy of this software and associated documentation

# files (the "Software"), to deal in the Software without

# restriction, including without limitation the rights to use,

# copy, modify, merge, publish, distribute, sublicense, and/or sell

# copies of the Software, and to permit persons to whom the

# Software is furnished to do so, subject to the following

# conditions:

# The above copyright notice and this permission notice shall be

# included in all copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

# OTHER DEALINGS IN THE SOFTWARE.

"""

This small application will build and draw a graph for a given finite definite automaton described

as a labelled transition system.

This is a very naive, probably useless, possibly incorrect, barely tested implementation. No

validation is ever performed. Take care or it will burn your house and kill your cat.

"""

# Module metadata

__authors__ = "Pedro Matiello"

__license__ = "MIT"

# Imports

import sys

sys.path.append('..')

import graph

sys.path.append('/usr/lib/graphviz/python/')

import gv

def load_automaton(filename):

	"""

	Read a automaton described as a labelled transition system and build the equivalent graph.

	@type  filename: string

	@param filename: Name of the file containing the LTS-described automaton.

	@rtype:  graph

	@return: Automaton's graph.

	"""

	gr = graph.digraph()

	infile = file(filename,'r')

	line = infile.readline()

	final = []

	while (line):

		line = line.replace("\n",'').split(' ')

		datatype = line[0]

		data = line[1:]

		if (datatype == 'Q'):

			# States

			for each in data:

				gr.add_node(each)

		if (datatype == 'A'):

			# Alphabet

			pass

		if (datatype == 'F'):

			# Final states

			final = final + data

		if (datatype == 's'):

			# Initial state

			gr.add_node('.',attrs=[('shape','point')])

			gr.add_edge('.',data[0])

		if (datatype == 't'):

			# Transitions

			if (gr.has_edge(data[1], data[2])):

				gr.set_edge_label(data[1], data[2], \

					gr.get_edge_label(data[1], data[2]) + ', ' + data[0])

			else:

				gr.add_edge(data[1], data[2], label=data[0])

		line = infile.readline()

	for node in gr:

		if (node in final and node != '.'):

			gr.add_node_attribute(node, ('shape','doublecircle'))

		elif (node != '.'):

			gr.add_node_attribute(node, ('shape','circle'))

	return gr, final

# Main

try:

	filename = sys.argv[1]

	gr, final = load_automaton(sys.argv[1])

	dot = gr.write(fmt='dot')

except IndexError:

	print "Syntax: %s filename" % sys.argv[0]

	sys.exit(1)

except IOError:

	print "Can't open file %s" % filename

	sys.exit(2)

# Print graph as PNG image

gvv = gv.readstring(dot)

gv.layout(gvv,'circo')

gv.render(gvv,'png',filename + '.png')