#!/usr/bin/env python3
from http.server import BaseHTTPRequestHandler, HTTPServer
from subprocess import Popen, PIPE
from shlex import quote

import argparse
import sys

def server_class_factory(command):
    class MyServer(BaseHTTPRequestHandler):
        def do_GET(self):
            self.handle_all()
        def do_POST(self):
            self.handle_all()
        def do_PUT(self):
            self.handle_all()
        def handle_all(self):
            self.send_response(200)
            self.send_header("Content-type", "text/html")
            self.end_headers()
            content = self.rfile.read(int(self.headers.get('Content-Length', 0)))
            p = Popen(command + [quote(self.command), quote(self.path)], stdin=PIPE, shell=False)
            p.communicate(input=content)

        def log_message(self, format, *args):
            return
    return MyServer

if __name__ == "__main__":  
    parser = argparse.ArgumentParser(description='shellsrv - Translate HTTP requests to command invocations on the host system.\n\n\nEach GET request results in the execution of COMMAND ARGS GET <path>. Other HTTP verbs might be added later.', prog='shellsrv')

    parser.add_argument('--host', '-H', type=str, help='HTTP server host, default 0.0.0.0', default="0.0.0.0")
    parser.add_argument('--port', '-p', type=int, help='HTTP server port, default 8080', default=8080)
    parser.add_argument('--limit', '-n', type=int, help='Close the server after limit requests', default=-1)
    parser.add_argument('command', metavar='COMMAND', type=str, nargs=1, help='command to call')
    parser.add_argument('args', metavar='ARG', type=str, nargs='*', help='args of the command to call')

    args = parser.parse_args()

    command = args.command + args.args
    request_limit = args.limit

    server = HTTPServer((args.host, args.port), server_class_factory(command))
    print("Server started http://%s:%s" % (args.host, args.port), file=sys.stderr)

    if request_limit < 0:
        try:
            server.serve_forever()
        except KeyboardInterrupt:
            pass
    else:
        for _ in range(request_limit):
            server.handle_request()

    server.server_close()