import slack
import os
import re
import ssl as ssl_lib
import certifi

from message import SlackMessage

class SlackReceiver() :
   def __init__(self, token, log, callback) :
      self.token = token
      self.ssl_context = ssl_lib.create_default_context(cafile=certifi.where())
      self.callback = callback
      self.log = log

   def start(self) :
      self.rtm_client = slack.RTMClient(token=self.token, ssl=self.ssl_context)
      @slack.RTMClient.run_on(event="message")
      def receive(**payload) :
         msg = self.parse(payload)
         if msg is not None:
            self.receive(msg)
      print("Starting")
      self.rtm_client.start()

   def parse(self, payload) :
      self.log.debug("slack message received: {}".format(payload))
      if 'data' in payload and 'bot_id' in payload['data'] and payload['data']['bot_id'] == 'BNYAX72BB':
         # it's the bot's response, ignore it
         return None
      if 'data' in payload and 'user' in payload['data'] and payload['data']['user'] == 'UNS0QKMMY':
         # it's the bot uploading files, ignore it
         return None
      if 'data' in payload and (
            ('text' in payload['data'] and '<@UNS0QKMMY>' not in payload['data']['text']) 
            and ('channel' in payload['data'] and not payload['data']['channel'].startswith('DP'))
         ):
         # message in a channel and the bot wasn't pinged, or was not a direct message - ignore
         self.log.debug("received message, but I wasn't pinged or DM'ed")
         return None
      if 'data' in payload and 'text' in payload['data'] and '<@UNS0QKMMY>' in payload['data']['text']:
         # remove the ping text
         payload['data']['text'] = re.sub('\\<@UNS0QKMMY\\>', '', payload['data']['text'])
      return SlackMessage(payload)

   def receive(self, msg) :
      text = msg.text.split()
      channel = msg.channel
      ID = text[0] if len(text) > 0 else None
      interval = text[1] if len(text) > 1 else None
      step = text[2] if len(text) > 2 else None
      self.callback(channel, ID, interval, step)