#!/usr/bin/env python

import re
from translator import Translator
from dfareg import CallGraph, Regexp

class DotTranslator(Translator):
    """
    DotToranslator
    This Class can translate from DFA or NFA into Dot
    Dot is Graph-generater using TeX.
    --code/graph/makepdf.sh is generate graph script.
    >>> string = \"(A|B)*C\"
    >>> reg = Regexp(string)
    >>> dfacg = CallGraph(reg.dfa)
    >>> nfacg = CallGraph(reg.nfa)
    >>> DotTranslator(string, dfacg).translate()
    >>> DotTranslator(string, nfacg).translate()
    """
    def __init__(self, regexp, cg):
        Translator.__init__(self, regexp, cg)
        if self.cg.type is "DFA":
            self.name_hash = self.create_name_hash()

    def modify_state_name(self, state_name):
        if self.cg.type is "DFA":
            return "s"+self.name_hash[state_name]
        else:
            return "s"+state_name

    def emit_from_callgraph(self):
        self.emit('''
digraph G{
\td2tdocpreamble = "\\usetikzlibrary{automata}";
\td2tfigpreamble = "\\tikzstyle{every state}= \\
\t[draw=blue!50,very thick,shape=circle, fill=blue!20]";
\tnode [style="state"];
\tedge [lblstyle="fill=blue!20", style="arrows=->", topath="bend left"];
''')

        self.emit("\t%s [style=\"state, initial\"]\n" % (self.modify_state_name(self.cg.start)))
        for accept in self.cg.accepts:
            self.emit("\t%s [style=\"state, accepting\"]\n" % (self.modify_state_name(accept)))

        for cur_state, trans in self.cg.map.iteritems():
            for input, next_states in trans.iteritems():
                if input is "" : input = "$\\varepsilon$"
                for next_state in next_states:
                    self.emit("\t%s -> %s [texlbl=\"%s\"]\n"
                              % (self.modify_state_name(cur_state), self.modify_state_name(next_state), input))

        self.emit("}")


def test():
    import doctest
    doctest.testmod()
    '''
    reg = Regexp("(A|B)*C")
    ct = CTranslator(reg.regexp, CallGraph(reg.dfa))
    ct.translate()
    '''

if __name__ == '__main__' : test()