import logging
import time
import json

import signal
import sys
import sqlalchemy

from itertools import islice
from twitter import TwitterHTTPError

from bitter.models import Following, User, ExtractorEntry, make_session

logger = logging.getLogger(__name__)


def signal_handler(signal, frame):
    logger.info('You pressed Ctrl+C!')
    sys.exit(0)


def get_users(wq, ulist, by_name=False, queue=None, max_users=100):
    t = 'name' if by_name else 'uid'
    logger.debug('Getting users by {}: {}'.format(t, ulist))
    ilist = iter(ulist)
    while True:
        userslice = ",".join(islice(ilist, max_users))
        if not userslice:
            break
        try:
            if by_name:
                resp = wq.users.lookup(screen_name=userslice)
            else:
                resp = wq.users.lookup(user_id=userslice)
        except TwitterHTTPError as ex:
            if ex.e.code in (404,):
                resp = []
            else:
                raise
        if not resp:
            logger.debug('Empty response')
        for user in resp:
            user = trim_user(user)
            if queue:
                queue.put(user)
            else:
                yield user

def trim_user(user):
    if 'status' in user:
        del user['status'] 
    if 'follow_request_sent' in user:
        del user['follow_request_sent']
    if 'created_at' in user:
        ts = time.strftime('%s', time.strptime(user['created_at'],'%a %b %d %H:%M:%S +0000 %Y'))
        user['created_at_stamp'] = ts
        del user['created_at']
    user['entities'] = json.dumps(user['entities'])
    return user


def add_user(session, user, enqueue=False):
    user = trim_user(user)
    olduser = session.query(User).filter(User.id==user['id'])
    if olduser:
        olduser.delete()
    user = User(**user) 
    session.add(user)
    if extract:
        logging.debug('Adding entry')
        entry = session.query(ExtractorEntry).filter(ExtractorEntry.user==user.id).first()
        if not entry:
            entry = ExtractorEntry(user=user.id)
            session.add(entry)
        logging.debug(entry.pending)
        entry.pending = True
        entry.cursor = -1
        session.commit()
    

# TODO: adapt to the crawler
def extract(wq, recursive=False, user=None, initfile=None, dburi=None, extractor_name=None):
    signal.signal(signal.SIGINT, signal_handler)
    
    w = wq.next()
    if not dburi:
        dburi = 'sqlite:///%s.db' % extractor_name

    session = make_session(dburi)

    if initfile:
        screen_names = []
        user_ids = []
        if not user:
            logger.info("No user. I will open %s" % initfile)
            with open(initfile, 'r') as f:
                for line in f:
                    user = line.strip().split(',')[0]
                    try:
                        int(user)
                        user_ids.append(user)
                    except ValueError:
                        screen_names.append(user.split('@')[-1])
        else:
            try:
                user_ids.append(int(user))
                logger.info("Added id")
            except Exception as ex:
                logger.info("Exception: {}".format(ex))
                logger.info("Added screen_name")
                screen_names.append(user)
        nusers = list(get_users(wq, screen_names, by_name=True))
        if user_ids:
            nusers += list(get_users(wq, user_ids, by_name=False))

        for i in nusers:
            add_user(session, i, enqueue=True)
    else:
        logger.info('Using pending users from last session')


    total_users = session.query(sqlalchemy.func.count(User.id)).scalar()
    logging.info('Total users: {}'.format(total_users))
    def pending_entries():
        pending = session.query(ExtractorEntry).filter(ExtractorEntry.pending == True).count() 
        logging.info('Pending: {}'.format(pending))
        return pending

    while pending_entries() > 0:
        logger.info("Using account: %s" % w.name)
        candidate, entry = session.query(User, ExtractorEntry).\
                           filter(ExtractorEntry.user == User.id).\
                           filter(ExtractorEntry.pending == True).\
                           order_by(User.followers_count).first()
        if not candidate:
            break
        pending = True
        cursor = entry.cursor
        uid = candidate.id
        uobject = session.query(User).filter(User.id==uid).first()
        name = uobject.screen_name if uobject else None

        logger.info("#"*20)
        logger.info("Getting %s - %s" % (uid, name))
        logger.info("Cursor %s" % cursor)
        logger.info("Pending: %s/%s" % (session.query(ExtractorEntry).filter(ExtractorEntry.pending==True).count(), total_users))
        try:
            resp = wq.followers.ids(user_id=uid, cursor=cursor)
        except TwitterHTTPError as ex:
            if ex.e.code in (401, ):
                logger.info('Not authorized for user: {}'.format(uid))
                resp = {}
        if 'ids' in resp:
            logger.info("New followers: %s" % len(resp['ids']))
            if recursive:
                newusers = get_users(wq, resp)
                for user in newusers:
                    add_user(session, newuser, enqueue=True)
            for i in resp['ids']:
                existing_user = session.query(Following).\
                                filter(Following.isfollowed==uid).\
                                filter(Following.follower==i).first()
                now = int(time.time())
                if existing_user:
                    existing_user.created_at_stamp = now
                else:
                    f = Following(isfollowed=uid,
                                  follower=i,
                                  created_at_stamp=now)
                    session.add(f)

            total_followers = candidate.followers_count
            fetched_followers = session.query(Following).filter(Following.isfollowed==uid).count()
            logger.info("Fetched: %s/%s followers" % (fetched_followers,
                                                      total_followers))
            cursor = resp["next_cursor"]
            if cursor > 0:
                pending = True
                logger.info("Getting more followers for %s" % uid)
            else:
                logger.info("Done getting followers for %s" % uid)
                cursor = -1
                pending = False
        else:
            logger.info("Error with id %s %s" % (uid, resp))
            pending = False

        entry.pending = pending
        entry.cursor = cursor
        logging.debug('Entry: {} - {}'.format(entry.user, entry.pending))

        session.add(candidate)
        session.commit()
        
        sys.stdout.flush()


def get_tweet(c, tid):
    return c.statuses.show(id=tid)

def search_tweet(c, query):
    return c.search.tweets(q=query)

def get_user(c, user):
    try:
        int(user)
        return c.users.lookup(user_id=user)[0]
    except ValueError:
        return c.users.lookup(screen_name=user)[0]