#!/usr/bin/env python

"""
@brief Collect Tweets
@author Remy Decoupes
@copyright CeCILL-B

Connect to Twitter stream using Twitter API and filter tweets which have to be retrieved with
    - Account to follow : accountsFollowed.csv
    - Hashtag to follow : keywordsFilter.csv

To install and run this script : please follow instructions from README.md
"""
import tweepy
import sys
import logging
from logging.handlers import RotatingFileHandler
import pandas as pd
import time


def exitscript(logger, message):
    """
    Log error and exit script
    :param logger: a logger object
    :param message: print a message
    :return:
    """
    logger.error("The program encountered an error")
    logger.error(msg)
    logger.error("End of execution.")
    sys.exit(1)


def logsetup():
    """
    Initiate a logger object :
        - Log in file : collectweets.log
        - also print on screen
    :return: logger object
    """
    logger = logging.getLogger()
    logger.setLevel(logging.DEBUG)
    formatter = logging.Formatter('%(asctime)s :: %(levelname)s :: %(message)s')
    file_handler = RotatingFileHandler('log/collectweets.log', 'a', 1000000, 1)
    file_handler.setLevel(logging.DEBUG)
    file_handler.setFormatter(formatter)
    logger.addHandler(file_handler)
    stream_handler = logging.StreamHandler()
    # Only display on screen INFO
    stream_handler.setLevel(logging.INFO)
    logger.addHandler(stream_handler)
    return logger


class Listener(tweepy.StreamListener):
    def __init__(self, output_file=sys.stdout, logger=sys.stdout):
        super(Listener, self).__init__()
        self.output_file = output_file
        self.logger = logger
        self.logger.info("initiate stream listener")

    def on_status(self, status):
        try:
            print(status._json, file=self.output_file)
        except:
            msg = "can not save tweets in file"+str(self.output_file)
            exitscript(logger, msg)

    def on_error(self, status_code):
        logger.error("Error on stream twitter: "+str(status_code))
        return False


if __name__ == '__main__':
    # initialize a logger :
    logger = logsetup()
    logger.info("Collect tweets : start")

    # try import credentials of MOODTwitter account
    try:
        from params import credentials
    except ImportError:
        msg = 'it seems there is no file named :"credentials.py"'
        exitscript(logger, msg)

    # Access and authorize on MOOD twitter Account
    try:
        auth = tweepy.OAuthHandler(credentials.consumer_key, credentials.consumer_secret)
        auth.set_access_token(credentials.access_token, credentials.access_token_secret)
        api = tweepy.API(auth)
        # Get the User object for twitter...
        accountused = api.me()
        logger.info("Log with: " + accountused.name)
    except tweepy.TweepError as twe:
        msg = "Wrong credentials: please check credentials.py"
        exitscript(logger, msg)
    except Exception as e:
        msg = "Please double check credentials.py :" + e
        exitscript(logger, msg)

    # Get twitter ID of account
    accounttofollowed = pd.read_csv("params/accountsFollowed.csv")
    accounttofollowedlist = accounttofollowed['twitterID'].tolist()
    accounttofollowedlist = list(map(str, accounttofollowedlist))

    # Start a Twitter stream
    timestr = time.strftime("%Y%m%d-%H%M%S")
    tweetouputfilename = "output/tweetoutput"+timestr+".jsonl"
    tweetoutput = open(tweetouputfilename, 'w')
    myStreamListener = Listener(tweetoutput, logger)
    stream = tweepy.Stream(auth=api.auth, listener=myStreamListener)
    try:
        logger.info("Start streaming")
        stream.filter(follow=accounttofollowedlist)
    except KeyboardInterrupt as e:
        logger.info("Stream Keyboard Interrupt")
    finally:
        stream.disconnect()
        tweetoutput.close()

    logger.info("Collect tweets : proceeded normally")