#! /usr/bin/env python
# -*- Mode: python; py-indent-offset: 4; tab-width: 8; indent-tabs-mode: t; -*-

import pprint
import os
import sys
import subprocess
import json
import argparse
import io
import time

from flask import Flask, json, Response, render_template, make_response, request

#
# curl http://127.0.0.1:8080/wm/topology/route/00:00:00:00:00:00:0a:01/1/00:00:00:00:00:00:0a:04/1/json
#

## Global Var ##
ControllerIP="127.0.0.1"
ControllerPort=8080

DEBUG=0
pp = pprint.PrettyPrinter(indent=4)

app = Flask(__name__)

## Worker Functions ##
def log_error(txt):
  print '%s' % (txt)

def debug(txt):
  if DEBUG:
    print '%s' % (txt)

# @app.route("/wm/topology/route/<srcdpid>/<srcport>/<destdpid>/<destport>/json")
def shortest_path(v1, p1, v2, p2):
  try:
    command = "curl -s http://%s:%s/wm/topology/route/%s/%s/%s/%s/json" % (ControllerIP, ControllerPort, v1, p1, v2, p2)
    result = os.popen(command).read()
    parsedResult = json.loads(result)
  except:
    log_error("Controller IF has issue")
    exit(1)

  debug("shortest_path %s" % command)
  debug("parsed %s" % parsedResult)

  for v in parsedResult:
    dpid = v['switch'];
    port = v['port'];
    print "PathEntry: (%s, %s)" % (dpid, port)


if __name__ == "__main__":
  usage_msg = "Usage: %s <src-dpid> <src-port> <dest-dpid> <dest-port>" % (sys.argv[0])

  # app.debug = False;

  # Usage info
  if len(sys.argv) > 1 and (sys.argv[1] == "-h" or sys.argv[1] == "--help"):
    print(usage_msg)
    exit(0)

  # Check arguments
  if len(sys.argv) < 5:
    log_error(usage_msg)
    exit(1)

  # Do the work
  shortest_path(sys.argv[1], sys.argv[2], sys.argv[3], sys.argv[4]);