lonsdaleite

#!/usr/bin/python
# vim: ft=python

import sys, getopt, webbrowser, re

def usage():
  print("""
  -d  dump graph after parsing
  -c  expect input piped from Clasp's output
  -u  construct URL for Google's GraphViz Charts API
  -b  open that URL in the default web browser
  """)

def main():
  expectClasp = False
  constructUrl = False
  showInBrowser = False
  dumpGraph = False

  try:
    opts, args = getopt.getopt(sys.argv[1:], "dcub")
  except getopt.GetoptError, err:
    print str(err)
    usage()
    sys.exit(2)  

  for o, a in opts:
    if o == "-d":
      dumpGraph = True
    elif o == "-c":
      expectClasp = True
    elif o == "-u":
      constructUrl = True
    elif o == "-b":
      showInBrowser = True

  patternSpecs = {
      "type": 1,
      "engine": 1,
      "node": 1,
      "edge": 2,
      "graph_attr": 2,
      "node_attr": 3,
      "edge_attr": 4,
      "global_node_attr": 2,
      "global_edge_attr": 2}
  
  patterns = {}
  for k, v in patternSpecs.items():
    functor = "graphviz_" + k
    args = "\(" + ",".join(["(.*?)"] * v) + "\)"
    patterns[k] = re.compile(functor + args)

  graph = {}

  for k in patternSpecs.keys():
    graph[k] = []

  graph['type'].append(('graph',))
  graph['engine'].append(('dot',))
  
  def consider(term):
    for k, v in patterns.items():
      match = v.match(term)
      if match:
        graph[k].append(match.groups())
        break

  if expectClasp:
    # look for all of the facts on a single line joined by spaces
    for line in sys.stdin.readlines():
      line = line.strip()
      if line and line[0].islower():
        terms = line.split(" ") # TODO: handle embedded spaces
        for t in terms:
          consider(t)
  else:
    # look for one fact per line
    for line in sys.stdin.readlines():
      consider(line.strip())

  if dumpGraph:
    print(graph)

  a_list = lambda seq: "[" + (",".join("%s=%s" % kv for kv in seq)) + "]"


  graphType = graph['type'][-1][0]
  connector = "->" if graphType == "digraph" else "--"
  
  graphvizCode = graphType

  graphvizCode += '{'
  
  if graph['graph_attr']:
      graphvizCode += "graph" + a_list(graph['graph_attr'])
      graphvizCode += ';'
  
  if graph['global_node_attr']:
      graphvizCode += "node" + a_list(graph['global_node_attr'])
      graphvizCode += ';'
  
  if graph['global_edge_attr']:
      graphvizCode += "edge" + a_list(graph['global_edge_attr'])
      graphvizCode += ';'
  
  nodes = []
  for (n1,) in graph['node']:
    attrs = [(k,v) for n1t,k,v in graph['node_attr'] if n1t == n1]
    nodes.append(n1 + a_list(attrs) if attrs else n1)
  graphvizCode += ';'.join(nodes)
  graphvizCode += ';'
  
  edges = []
  for (n1,n2) in graph['edge']:
    attrs = [(k,v) for n1t,n2t,k,v in graph['edge_attr'] \
                   if n1t == n1 and n2t == n2]
    edges.append(n1 + connector + n2 + (a_list(attrs) if attrs else ""))
  graphvizCode += ';'.join(edges)

  graphvizCode += '}'

  if constructUrl:
    cht = "gv:%s" % graph['engine'][-1][0]
    chl = graphvizCode
    url = "http://chart.googleapis.com/chart?chl=" + chl + "&cht=" + cht
    if showInBrowser:
      webbrowser.open(url)
    else:
      print(url)
  else:
    print(graphvizCode)

  
if __name__ == "__main__":
  main()