#!/usr/bin/env python3

import os, setuptools, socketserver, sys, syslog, threading

SYSLOG = 0
STDOUT = 1
STDDEB = 2 # STDOUT + Debug

exec("logging = %s or STDOUT" % setuptools.getSetting("Log", "sink"))

def logger(message, prio=syslog.LOG_INFO, sink=logging):
 if sink in (STDOUT, STDDEB):
  if prio not in (syslog.LOG_NOTICE, syslog.LOG_INFO, syslog.LOG_DEBUG):
   print(message)
   sys.stderr.write(message)
  elif prio != syslog.LOG_DEBUG or sink == STDDEB:
   print(message)
 elif sink == SYSLOG:
  syslog.openlog("KumiStatusServer", syslog.LOG_PID)
  syslog.syslog(prio, message)
 else:
  try:
   sys.stderr.write("Unknown logging level %s, assuming STDOUT from now on." % str(sink))
  except:
   pass
  logging = STDOUT
  logger(message, prio, logging)

def worker(message):
 command = message.split()
 if command[0].lower() in ("heartbeat", "hb", "ping"):
  return "HB: Still here? Wow."

class TCPHandler(socketserver.StreamRequestHandler):
 def readString(self):
  return self.rfile.readline().strip()

 def sendString(self, string):
  self.request.sendall((string + "\n").encode('utf8'))

 def handle(self):
  remote = self.client_address[0] + ":" + str(self.client_address[1])
  logger("New connection from %s." % remote, syslog.LOG_INFO)
  self.sendString("HI: Kumi Status v0.8.15")
  while True:
   message = self.readString().decode('utf8')
   if not message:
    logger("Connection from %s closed." % remote, syslog.LOG_DEBUG)
    break
   logger("%s said: %s" % (remote, message))
   response = worker(message)
   if response:
    self.sendString(response)
    logger("Sent to %s: %s" % (remote, response), syslog.LOG_DEBUG)

class TCPServer(socketserver.ThreadingMixIn, socketserver.TCPServer):
 pass

def shutdown(reboot = False, status = 0):
 if reboot:
  args = sys.argv[:]
  args.insert(0, sys.executable)
  try:
   os.execv(sys.executable, args)
  except:
   logger("Restart failed. Shutting down.")
   exit(2)
 else:
  exit(status)

if __name__ == "__main__":
 socketserver.TCPServer.allow_reuse_address = True
 try:
  server = TCPServer((setuptools.getSetting("Server", "bind"), int(setuptools.getSetting("Server", "port"))), TCPHandler)
 except:
  logger("Unable to bind on %s:%s. Make sure the port is not in use or use a different port.")
  shutdown(status=1)
 logger("Kumi Status server running on %s:%s." % (setuptools.getSetting("Server", "bind"), setuptools.getSetting("Server", "port")))

 try:
  thread = threading.Thread(target=server.serve_forever(), daemon=True)
 except KeyboardInterrupt:
  logger("Caught KeyboardInterrupt. Shutting down.")
  shutdown()
 except EOFError:
  logger("Caught EOF. Shutting down.")
  shutdown()
 except BaseException as e:
  logger(str(e), syslog.LOG_CRIT)
  logger("Caught some bad exception. Trying to reload...", syslog.LOG_CRIT)
  shutdown(reboot=True)