#!/usr/bin/env python

# Thierry Parmentelat <thierry.parmentelat@inria.fr>
# Copyright (C) 2010 INRIA 
#

# this is a small and simple standalone utility
# designed to run in slice-space
# we keep this in python2 for now until python3
# can be taken for granted in sliceimage

from __future__ import print_function

import sys
import time
import subprocess
import socket
import SocketServer
import threading
from optparse import OptionParser    

def myprint(message, id='client'):
    now = time.strftime("%H:%M:%S", time.localtime())
    print("* {now} ({id}) -- {message}".format(**locals()))
    sys.stdout.flush()

def show_network_status(id):
    myprint("ip address show", id=id)
    subprocess.call(['ip', 'address', 'show'])
    myprint("ip route show", id=id)
    subprocess.call(['ip', 'route', 'show'])

class EchoRequestHandler(SocketServer.StreamRequestHandler):
    def handle(self):
        line = self.rfile.readline()
        self.wfile.write(line)

class UppercaseRequestHandler(SocketServer.StreamRequestHandler):
    def handle(self):
        line = self.rfile.readline()
        self.wfile.write(line.upper())

class Server:
    """
    A TCP server, running for some finite amount of time
    """
    def main(self):
        parser = OptionParser()
        parser.add_option("-p", "--port", action="store", dest="port", type="int",
                          default=10000, help="port number")
        parser.add_option("-a", "--address", action="store", dest="address", 
                          default=socket.gethostname(), help="address")
        parser.add_option("-t", "--timeout", action="store", dest="timeout", type="int",
                          default="0")
        (options, args) = parser.parse_args()

        if len(args) != 0:
            parser.print_help()
            sys.exit(1)

        myprint("==================== tcptest.py server", id='server')
        show_network_status(id='server')
        server = SocketServer.TCPServer((options.address, options.port),
                                        UppercaseRequestHandler)
        try:
            if options.timeout:
                t = threading.Thread(target=server.serve_forever)
                t.setDaemon(True) # don't hang on exit
                t.start()
                time.sleep(options.timeout)
                sys.exit(0)
            else:
                server.serve_forever()        
        except KeyboardInterrupt as e:
            print('Bailing out on keyboard interrupt')
            sys.exit(1)
            
class Ready:
    """
    A utility that does exit(0) iff network as perceived
    from the sliver is ready. Designed to be run before Server,
    so one can wait for the right conditions.
    """
    def main(self):
        parser = OptionParser()
        # by default use another port so we don't run into
        # the SO_LINGER kind of trouble
        parser.add_option("-p", "--port", action="store", dest="port", type="int",
                          default=9999, help="port number")
        parser.add_option("-a", "--address", action="store", dest="address", 
                          default=socket.gethostname(), help="address")
        (options, args) = parser.parse_args()

        myprint("==================== tcptest.py ready", id='ready')
        def can_bind ():
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            try:
                s.bind((options.address, options.port))
                return True
            except Exception as e:
                print(e)
                return False

        def eth0_has_ipv4():
            command = "ip address show eth0 | grep -q ' inet '"
            return subprocess.check_call(command, shell=True) == 0

        sys.exit(0 if can_bind() and eth0_has_ipv4() else 1)
        
class Client:
    """
    Runs a client against a Server instance
    """
    def main(self):
        parser = OptionParser()
        parser.add_option("-p","--port", action="store", dest="port", type="int",
                          default=10000, help="port number")
        parser.add_option("-a","--address", action="store", dest="address", 
                          default=socket.gethostname(), help="address")
        parser.add_option("-s","--sleep", action="store", dest="sleep", type="int",
                          default=1, help="sleep seconds")
        parser.add_option("-l","--loops", action="store", dest="loops", type="int",
                          default=1, help="iteration loops")
        
        (options, args) = parser.parse_args()
        if len(args) != 0:
            parser.print_help()
            sys.exit(1)

        myprint("==================== tcptest.py client", id='client')
        result=True
        for i in range(1,options.loops+1):
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.connect((options.address, options.port))
            mout=i*'ping ' + '\n'
            min=mout.upper()
            if s.send(mout) != len(mout):
                myprint("cannot send {}".format(mout.strip()))
                result=False
                break
            line=s.recv(len(min))
            if line is not line:
                myprint("unexpected reception\ngot:{}\nexpected: {}".format(line, min))
                result = False
            else:
                myprint("OK:{}".format(mout.strip()))
            # leave the connection open, but the last one (so 1 iter returns fast)
            if i != options.loops:
                time.sleep(options.sleep)
            myprint("disconnecting")
            s.close()
        myprint("Done")
        exit_return=0
        if not result:
            exit_return=1
        sys.exit(exit_return)

if __name__ == '__main__':
    for arg in sys.argv[1:]:
        if arg.find("client") >= 0:
            sys.argv.remove(arg)
            Client().main()
        elif arg.find("server") >= 0:
            sys.argv.remove(arg)
            Server().main()
        elif arg.find("ready") >= 0:
            sys.argv.remove(arg)
            Ready().main()
    print('you must specify either --client or --server')
    sys.exit(1)