#!/usr/bin/env python3
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# Copyright (C) 2018, Hisilicon Technologies Co., Ltd. All Rights Reserved.
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"""presenter server module"""

import os
import sys
import signal
import argparse
import logging

WEB_SERVER = None
APP_SERVER = None
RUN_SERVER = None
SERVER_TYPE = ""
USAGE_INFO = "python3 prensenter_server.py [-h] --app \n\t\t\t\t{body_pose}"

BODY_MAP = {"web_server": "body_pose.src.web",
                    "app_server": "body_pose.src.body_pose_server"
                  }

APP_CONF_MAP = {"body_pose": BODY_MAP}


def arg_parse():
    '''arg_parse'''
    global WEB_SERVER
    global APP_SERVER
    global SERVER_TYPE

    parser = argparse.ArgumentParser(usage=USAGE_INFO)
    parser.add_argument('--app', type=str, required=True,
                        choices=['body_pose'],
                        help="Application type corresponding to Presenter Server.")
    args = parser.parse_args()
    SERVER_TYPE = args.app
    app_conf = APP_CONF_MAP.get(SERVER_TYPE)
    
    WEB_SERVER = __import__(app_conf.get("web_server"), fromlist=True)
    APP_SERVER = __import__(app_conf.get("app_server"), fromlist=True)

def start_app():
    global RUN_SERVER
    # start socket server for presenter agent communication
    RUN_SERVER = APP_SERVER.run()
    if RUN_SERVER is None:
        return False

    logging.info("presenter server starting, type: %s", SERVER_TYPE)
    # start web ui
    return WEB_SERVER.start_webapp()

def stop_app():
    WEB_SERVER.stop_webapp()
    RUN_SERVER.stop_thread()


def close_all_thread(signum, frame):
    '''close all thread of the process, and exit.'''
    logging.info("receive signal, signum:%s, frame:%s", signum, frame)
    stop_app()

    logging.info("presenter server exit by Ctrl + c")

    sys.exit()

def check_server_exist():
    pid = os.getpid()

    cmd = "ps -ef|grep -v {}|grep -w presenter_server|grep {}" \
            .format(pid, SERVER_TYPE)

    ret = os.system(cmd)

    return ret

def main_process():
    '''Main function entrance'''
    arg_parse()

    if check_server_exist() == 0:
        print("Presenter Server type \"%s\" already exist!" %(SERVER_TYPE))
        return True
    # process signal, when receive "Ctrl + c" signal,
    # stop all thead and exit the progress.
    signal.signal(signal.SIGINT, close_all_thread)
    signal.signal(signal.SIGTERM, close_all_thread)
    start_app()

    return True

if __name__ == "__main__":
    main_process()