#!/usr/bin/python3

import asyncio
import configparser
import json
import logging
import pathlib

import discord
import persistqueue
import tweepy


TIMEOUT = 1

TWITTER_USER_URL = 'https://twitter.com/i/user/'
TWITTER_STATUS_URL = 'https://twitter.com/i/status/'
TWITTER_ICON_URL = 'https://abs.twimg.com/icons/apple-touch-icon-192x192.png'
TWITTER_COLOR = 0x1da1f2


logger = logging.getLogger('discord')
logger.addHandler(logging.StreamHandler())
logger.setLevel(logging.INFO)


config = configparser.ConfigParser()
config.read('settings.cfg')


storage_path = config.get('General', 'storage_path')

token = config.get('Discord', 'token')
channel_id = config.getint('Discord', 'channel_id')

consumer_key = config.get('Twitter', 'consumer_key')
consumer_secret = config.get('Twitter', 'consumer_secret')


class Bot(discord.Client):
    def get_api(self, user_id):
        handler = tweepy.OAuthHandler(consumer_key, consumer_secret)
        with open(pathlib.Path(storage_path, 'tokens.json'), 'r') as f:
            tokens = json.load(f)
        access_token = tokens.get(user_id)
        if not access_token:
            return None
        handler.set_access_token(*access_token)
        return tweepy.API(handler)

    def make_embed(self, tweet):
        tweet_url = '{0}{1}'.format(TWITTER_STATUS_URL, tweet.get('id_str'))
        author_url = '{0}{1}'.format(TWITTER_USER_URL, tweet.get('user', {}).get('id_str'))
        author_handle = '@{0}'.format(tweet.get('user', {}).get('screen_name'))
        description = '{0}\n[{1}]({1})'.format(tweet.get('text'), tweet_url)
        embed = discord.Embed(
            description=description,
            url=tweet_url,
            color=TWITTER_COLOR
        )
        embed.set_author(
            name='{0} ({1})'.format(tweet.get('user', {}).get('name'), author_handle),
            url=author_url,
            icon_url=tweet.get('user', {}).get('profile_image_url_https')
        )
        embed.set_footer(
            text='Twitter',
            icon_url=TWITTER_ICON_URL
        )
        return embed

    async def process_event(self, data):
        tweets = data.get('tweet_create_events', [])
        if not tweets:
            return
        if 'user_has_blocked' in data:
            # ignore mentions
            return
        user_id = data.get('for_user_id')
        if not user_id:
            return
        api = self.get_api(user_id)
        if not api:
            return
        await self.wait_until_ready()
        channel = self.get_channel(channel_id)
        if channel:
            for tweet in tweets:
                await channel.send(embed=self.make_embed(tweet))


def main():
    bot = Bot()
    async def poll_queue():
        queue = persistqueue.SQLiteQueue(storage_path)
        while True:
            try:
                data = queue.get(block=False)
            except persistqueue.exceptions.Empty:
                await asyncio.sleep(TIMEOUT)
            else:
                try:
                    await bot.process_event(data)
                except Exception:
                    queue.put(data)
                    queue.task_done()
                    raise
    async def run_bot():
        while True:
            try:
                await bot.start(token)
            except Exception:
                await bot.logout()
    loop = asyncio.get_event_loop()
    try:
        asyncio.ensure_future(poll_queue())
        asyncio.ensure_future(run_bot())
        loop.run_forever()
    finally:
        loop.close()


if __name__ == '__main__':
    main()