from flask import Flask
from flask_restful import Resource, Api
from flask import jsonify
from flask import Response
from flask import request
from threading import Thread
from OpenSSL import crypto
import docker
import uuid
import signal
import time
import os
import re
import sys
import ssl
import socket

docker_client = docker.DockerClient(base_url='unix://var/run/docker.sock', version='auto')
app = Flask(__name__)
api = Api(app)

class containers_get(Resource):
  def get(self):
    containers = {}
    try:
      for container in docker_client.containers.list(all=True):
        containers.update({container.attrs['Id']: container.attrs})
      return containers
    except Exception as e:
      return jsonify(type='danger', msg=str(e))

class container_get(Resource):
  def get(self, container_id):
    if container_id and container_id.isalnum():
      try:
        for container in docker_client.containers.list(all=True, filters={"id": container_id}):
          return container.attrs
      except Exception as e:
          return jsonify(type='danger', msg=str(e))
    else:
      return jsonify(type='danger', msg='no or invalid id defined')

class container_post(Resource):
  def post(self, container_id, post_action):
    if container_id and container_id.isalnum() and post_action:
      if post_action == 'stop':
        try:
          for container in docker_client.containers.list(all=True, filters={"id": container_id}):
            container.stop()
          return jsonify(type='success', msg='command completed successfully')
        except Exception as e:
          return jsonify(type='danger', msg=str(e))

      elif post_action == 'start':
        try:
          for container in docker_client.containers.list(all=True, filters={"id": container_id}):
            container.start()
          return jsonify(type='success', msg='command completed successfully')
        except Exception as e:
          return jsonify(type='danger', msg=str(e))

      elif post_action == 'restart':
        try:
          for container in docker_client.containers.list(all=True, filters={"id": container_id}):
            container.restart()
          return jsonify(type='success', msg='command completed successfully')
        except Exception as e:
          return jsonify(type='danger', msg=str(e))

      elif post_action == 'exec':

        if not request.json or not 'cmd' in request.json:
          return jsonify(type='danger', msg='cmd is missing')

        if request.json['cmd'] == 'mailq':
          if 'items' in request.json:
            r = re.compile("^[0-9a-fA-F]+$")
            filtered_qids = filter(r.match, request.json['items'])
            if filtered_qids:
              if request.json['task'] == 'delete':
                flagged_qids = ['-d %s' % i for i in filtered_qids]
                sanitized_string = str(' '.join(flagged_qids));
                try:
                  for container in docker_client.containers.list(filters={"id": container_id}):
                    postsuper_r = container.exec_run(["/bin/bash", "-c", "/usr/sbin/postsuper " + sanitized_string])
                    return exec_run_handler('generic', postsuper_r)
                except Exception as e:
                  return jsonify(type='danger', msg=str(e))
              if request.json['task'] == 'hold':
                flagged_qids = ['-h %s' % i for i in filtered_qids]
                sanitized_string = str(' '.join(flagged_qids));
                try:
                  for container in docker_client.containers.list(filters={"id": container_id}):
                    postsuper_r = container.exec_run(["/bin/bash", "-c", "/usr/sbin/postsuper " + sanitized_string])
                    return exec_run_handler('generic', postsuper_r)
                except Exception as e:
                  return jsonify(type='danger', msg=str(e))
              if request.json['task'] == 'unhold':
                flagged_qids = ['-H %s' % i for i in filtered_qids]
                sanitized_string = str(' '.join(flagged_qids));
                try:
                  for container in docker_client.containers.list(filters={"id": container_id}):
                    postsuper_r = container.exec_run(["/bin/bash", "-c", "/usr/sbin/postsuper " + sanitized_string])
                    return exec_run_handler('generic', postsuper_r)
                except Exception as e:
                  return jsonify(type='danger', msg=str(e))
              if request.json['task'] == 'deliver':
                flagged_qids = ['-i %s' % i for i in filtered_qids]
                try:
                  for container in docker_client.containers.list(filters={"id": container_id}):
                    for i in flagged_qids:
                      postqueue_r = container.exec_run(["/bin/bash", "-c", "/usr/sbin/postqueue " + i], user='postfix')
                      # todo: check each exit code
                    return jsonify(type='success', msg=str("Scheduled immediate delivery"))
                except Exception as e:
                  return jsonify(type='danger', msg=str(e))
          elif request.json['task'] == 'list':
            try:
              for container in docker_client.containers.list(filters={"id": container_id}):
                mailq_return = container.exec_run(["/usr/sbin/postqueue", "-j"], user='postfix')
                return exec_run_handler('utf8_text_only', mailq_return)
            except Exception as e:
              return jsonify(type='danger', msg=str(e))
          elif request.json['task'] == 'flush':
            try:
              for container in docker_client.containers.list(filters={"id": container_id}):
                postqueue_r = container.exec_run(["/usr/sbin/postqueue", "-f"], user='postfix')
                return exec_run_handler('generic', postqueue_r)
            except Exception as e:
              return jsonify(type='danger', msg=str(e))
          elif request.json['task'] == 'super_delete':
            try:
              for container in docker_client.containers.list(filters={"id": container_id}):
                postsuper_r = container.exec_run(["/usr/sbin/postsuper", "-d", "ALL"])
                return exec_run_handler('generic', postsuper_r)
            except Exception as e:
              return jsonify(type='danger', msg=str(e))

        elif request.json['cmd'] == 'system':
          if request.json['task'] == 'df':
            if 'dir' in request.json:
              try:
                for container in docker_client.containers.list(filters={"id": container_id}):
                  df_return = container.exec_run(["/bin/bash", "-c", "/bin/df -H '" + request.json['dir'].replace("'", "'\\''") + "' | /usr/bin/tail -n1 | /usr/bin/tr -s [:blank:] | /usr/bin/tr ' ' ','"], user='nobody')
                  if df_return.exit_code == 0:
                    return df_return.output.rstrip()
                  else:
                    return "0,0,0,0,0,0"
              except Exception as e:
                return jsonify(type='danger', msg=str(e))

        elif request.json['cmd'] == 'reload':
          if request.json['task'] == 'dovecot':
            try:
              for container in docker_client.containers.list(filters={"id": container_id}):
                reload_return = container.exec_run(["/bin/bash", "-c", "/usr/local/sbin/dovecot reload"])
                return exec_run_handler('generic', reload_return)
            except Exception as e:
              return jsonify(type='danger', msg=str(e))
          if request.json['task'] == 'postfix':
            try:
              for container in docker_client.containers.list(filters={"id": container_id}):
                reload_return = container.exec_run(["/bin/bash", "-c", "/usr/sbin/postfix reload"])
                return exec_run_handler('generic', reload_return)
            except Exception as e:
              return jsonify(type='danger', msg=str(e))
          if request.json['task'] == 'nginx':
            try:
              for container in docker_client.containers.list(filters={"id": container_id}):
                reload_return = container.exec_run(["/bin/sh", "-c", "/usr/sbin/nginx -s reload"])
                return exec_run_handler('generic', reload_return)
            except Exception as e:
              return jsonify(type='danger', msg=str(e))

        elif request.json['cmd'] == 'sieve':
          if request.json['task'] == 'list':
            if 'username' in request.json:
              try:
                for container in docker_client.containers.list(filters={"id": container_id}):
                  sieve_return = container.exec_run(["/bin/bash", "-c", "/usr/local/bin/doveadm sieve list -u '" + request.json['username'].replace("'", "'\\''") + "'"])
                  return exec_run_handler('utf8_text_only', sieve_return)
              except Exception as e:
                return jsonify(type='danger', msg=str(e))
          elif request.json['task'] == 'print':
            if 'username' in request.json and 'script_name' in request.json:
              try:
                for container in docker_client.containers.list(filters={"id": container_id}):
                  sieve_return = container.exec_run(["/bin/bash", "-c", "/usr/local/bin/doveadm sieve get -u '" + request.json['username'].replace("'", "'\\''") + "' '" + request.json['script_name'].replace("'", "'\\''") + "'"])
                  return exec_run_handler('utf8_text_only', sieve_return)
              except Exception as e:
                return jsonify(type='danger', msg=str(e))

        elif request.json['cmd'] == 'maildir':
          if request.json['task'] == 'cleanup':
            if 'maildir' in request.json:
              try:
                for container in docker_client.containers.list(filters={"id": container_id}):
                  sane_name = re.sub(r'\W+', '', request.json['maildir'])
                  maildir_cleanup = container.exec_run(["/bin/bash", "-c", "if [[ -d '/var/vmail/" + request.json['maildir'].replace("'", "'\\''") + "' ]]; then /bin/mv '/var/vmail/" + request.json['maildir'].replace("'", "'\\''") + "' '/var/vmail/_garbage/" + str(int(time.time())) + "_" + sane_name + "'; fi"], user='vmail')
                  return exec_run_handler('generic', maildir_cleanup)
              except Exception as e:
                return jsonify(type='danger', msg=str(e))

        elif request.json['cmd'] == 'rspamd':
          if request.json['task'] == 'worker_password':
            if 'raw' in request.json:
              try:
                for container in docker_client.containers.list(filters={"id": container_id}):
                  worker_shell = container.exec_run(["/bin/bash"], stdin=True, socket=True, user='_rspamd')
                  worker_cmd = "/usr/bin/rspamadm pw -e -p '" + request.json['raw'].replace("'", "'\\''") + "' 2> /dev/null\n"
                  worker_socket = worker_shell.output;
                  try :
                    worker_socket.sendall(worker_cmd.encode('utf-8'))
                    worker_socket.shutdown(socket.SHUT_WR)
                  except socket.error:
                    return jsonify(type='danger', msg=str('socket error'))
                  worker_response = recv_socket_data(worker_socket)
                  matched = False
                  for line in worker_response.split("\n"):
                    if '$2$' in line:
                      matched = True
                      hash = line.strip()
                      hash_out = re.search('\$2\$.+$', hash).group(0)
                      f = open("/access.inc", "w")
                      f.write('enable_password = "' + re.sub('[^0-9a-zA-Z\$]+', '', hash_out.rstrip()) + '";\n')
                      f.close()
                      container.restart()
                  if matched:
                    return jsonify(type='success', msg='command completed successfully')
                  else:
                    return jsonify(type='danger', msg='command did not complete')
              except Exception as e:
                return jsonify(type='danger', msg=str(e))

        else:
          return jsonify(type='danger', msg='Unknown command')

      else:
        return jsonify(type='danger', msg='invalid action')

    else:
      return jsonify(type='danger', msg='invalid container id or missing action')

class GracefulKiller:
  kill_now = False
  def __init__(self):
    signal.signal(signal.SIGINT, self.exit_gracefully)
    signal.signal(signal.SIGTERM, self.exit_gracefully)

  def exit_gracefully(self, signum, frame):
    self.kill_now = True

def startFlaskAPI():
  create_self_signed_cert()
  try:
    ctx = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
    ctx.check_hostname = False
    ctx.load_cert_chain(certfile='/cert.pem', keyfile='/key.pem')
  except:
    print "Cannot initialize TLS, retrying in 5s..."
    time.sleep(5)
  app.run(debug=False, host='0.0.0.0', port=443, threaded=True, ssl_context=ctx)

def recv_socket_data(c_socket, timeout=10):
  c_socket.setblocking(0)
  total_data=[];
  data='';
  begin=time.time()
  while True:
    if total_data and time.time()-begin > timeout:
      break
    elif time.time()-begin > timeout*2:
      break
    try:
      data = c_socket.recv(8192)
      if data:
        total_data.append(data)
        #change the beginning time for measurement
        begin=time.time()
      else:
        #sleep for sometime to indicate a gap
        time.sleep(0.1)
        break
    except:
      pass
  return ''.join(total_data)

def exec_run_handler(type, output):
  if type == 'generic':
    if output.exit_code == 0:
      return jsonify(type='success', msg='command completed successfully')
    else:
      return jsonify(type='danger', msg='command failed: ' + output.output)
  if type == 'utf8_text_only':
    r = Response(response=output.output, status=200, mimetype="text/plain")
    r.headers["Content-Type"] = "text/plain; charset=utf-8"
    return r

def create_self_signed_cert():
  success = False
  while not success:
    try:
      pkey = crypto.PKey()
      pkey.generate_key(crypto.TYPE_RSA, 2048)
      cert = crypto.X509()
      cert.get_subject().O = "mailcow"
      cert.get_subject().CN = "dockerapi"
      cert.set_serial_number(int(uuid.uuid4()))
      cert.gmtime_adj_notBefore(0)
      cert.gmtime_adj_notAfter(10*365*24*60*60)
      cert.set_issuer(cert.get_subject())
      cert.set_pubkey(pkey)
      cert.sign(pkey, 'sha512')
      cert = crypto.dump_certificate(crypto.FILETYPE_PEM, cert)
      pkey = crypto.dump_privatekey(crypto.FILETYPE_PEM, pkey)
      with os.fdopen(os.open('/cert.pem', os.O_WRONLY | os.O_CREAT, 0o644), 'w') as handle:
        handle.write(cert)
      with os.fdopen(os.open('/key.pem', os.O_WRONLY | os.O_CREAT, 0o600), 'w') as handle:
        handle.write(pkey)
      success = True
    except:
      time.sleep(1)
      try:
        os.remove('/cert.pem')
        os.remove('/key.pem')
      except OSError:
        pass

api.add_resource(containers_get, '/containers/json')
api.add_resource(container_get, '/containers/<string:container_id>/json')
api.add_resource(container_post, '/containers/<string:container_id>/<string:post_action>')

if __name__ == '__main__':
  api_thread = Thread(target=startFlaskAPI)
  api_thread.daemon = True
  api_thread.start()
  killer = GracefulKiller()
  while True:
    time.sleep(1)
    if killer.kill_now:
      break
  print "Stopping dockerapi-mailcow"