#!/usr/bin/env python

# Module imports
import sys
import os
import time
import socket
from optparse import OptionParser

# Globals for this module
opts = None
args = None
PROFILE = 0

def main(argv=None):
    global opts
    
    # Process command line arguments
    
    if argv is None:
        processOptions(sys.argv[1:])
    else:
        processOptions(argv)

    listensock = serverSocket(opts)
    running = True
    while running:
        # The basic client loop: accept-process-close
        clientsock, addr = listensock.accept()
        if opts.verbose > 0:
            print 'Connected with %s:%d' % (addr[0],addr[1])

        # Get a "request"
        request = readLine(clientsock)
        if request != '':
            # Send a "response"
            timestr = time.asctime() + '\n'
            n = clientsock.sendall(timestr)
        elif opts.verbose > 0:
            print 'close received by client'
            
        clientsock.close()
    return

# Common network functions
def serverSocket(opts):
    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        s.bind((opts.addr, opts.port))
        if opts.reuse:
            s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        s.listen(opts.backlog)
    except socket.error, msg:
        print 'Failed to create/bind socket. Error code: %d, Error message: %s' % (msg[0],msg[1])
        sys.exit(1)

    # Get here on success of try block
    if opts.verbose > 0:
        print 'Socket created, bound, and listening'
    
    return s

def readLine(sock):
    buffer = ''
    ch = sock.recv(1)
    while ch != '\n' and ch != '':
        buffer += ch
        ch = sock.recv(1)
    if ch == '':
        buffer = ''
    else:
        buffer += ch
    return buffer

# Put together all command line options parsing in one place
def processOptions(argv):
    global opts
    global args
    
    try:
        # setup option parser
        parser = OptionParser()
        parser.add_option("-v", "--verbose", dest="verbose", action="count",
                          help="set verbosity level [default: %default]")
        parser.add_option("-r", "--reuse", dest="reuse", action="store_false",
                          help="set socket to not reuseaddr [default: %default]")
        parser.add_option("-a", "--addr", dest="addr", action='store',
                          help="set server listen address [default: \"%default\"]")
        parser.add_option("-p", "--port", dest="port", action='store', type='int',
                          help="set server port number [default: %default]")
        parser.add_option("-b", "--backlog", dest="backlog", action='store', type='int',
                          help="set server connection backlog [default: %default]")
    
        # set defaults
        parser.set_defaults(verbose=0, reuse=True, addr='', port=6666, backlog=32)
    
        # process options
        (opts, args) = parser.parse_args(argv)

    except Exception, e:
        sys.stderr.write("Error processing options; for help use --help")
        return 2
    
    if opts.verbose > 0:
      print("verbosity level = %d" % opts.verbose)
      print("args =", args)
    if opts.verbose > 0 and opts.reuse:
      print("reuse = %s" % str(opts.reuse))
    if opts.verbose > 0 and opts.addr:
      print("addr = %s" % opts.addr)
    if opts.verbose > 0 and opts.port:
      print("port = %d" % opts.port)
    if opts.verbose > 0 and opts.backlog:
      print("backlog = %d" % opts.backlog)


if __name__ == "__main__":
  if PROFILE:
    import cProfile
    import pstats
    profile_filename = '%s.txt' % sys.argv[0]
    cProfile.run('main()', profile_filename)
    statsfile = open("%s_stats.txt" % sys.argv[0], "wb")
    p = pstats.Stats(profile_filename, stream=statsfile)
    stats = p.strip_dirs().sort_stats('cumulative')
    stats.print_stats()
    statsfile.close()
    sys.exit(0)
  sys.exit(main())