import os
import time
import html
import json
import random
import logging
import asyncio
import tempfile
import functools
import mimetypes
import traceback
from itertools import zip_longest
from urllib.parse import urlparse, urlunparse
import yaml
import praw
import aiohttp
import aiocron
from telethon import TelegramClient, events
from telethon.utils import chunks

with open('config.yaml') as file:
    config_data = yaml.safe_load(file)

tg_api_id = config_data['telegram']['api_id']
tg_api_hash = config_data['telegram']['api_hash']
bot_token = config_data['telegram'].get('bot_token')

reddit_client_id = config_data['reddit']['client_id']
reddit_client_secret = config_data['reddit']['client_secret']

storage_chat = config_data['config'].get('storage_chat')
storage_msg_id = config_data['config'].get('storage_message_id')
send_to_chats = config_data['config']['send_to_chats']
subreddits = config_data['config']['subreddits']
bot_admins = config_data['config']['bot_admins']
cron_duration = config_data['config']['cron_duration']

logging.basicConfig(level=logging.INFO)
async def main():
    zws = '\u200b'
    client = await TelegramClient('redditbot', tg_api_id, tg_api_hash).start(bot_token=bot_token)
    client.parse_mode = 'html'
    session = aiohttp.ClientSession()
    reddit = praw.Reddit(client_id=reddit_client_id, client_secret=reddit_client_secret, user_agent='linux:redditbot:v1.0.0 (by /u/the_blank_x)')

    try:
        if storage_chat and storage_msg_id:
            await (await client.get_messages(storage_chat, ids=storage_msg_id)).download_media('redditbot.json')
        with open('redditbot.json') as file:
            seen_posts = json.load(file)
    except Exception:
        traceback.print_exc()
        seen_posts = []

    async def write_seen_posts():
        with open('redditbot.json', 'w') as file:
            json.dump(seen_posts, file)
        if storage_chat and storage_msg_id:
            await client.edit_message(storage_chat, storage_msg_id, file='redditbot.json')

    @aiocron.crontab(cron_duration)
    async def start_post():
        while True:
            random.shuffle(subreddits)
            to_break = False
            for subreddit_name in subreddits:
                subreddit = reddit.subreddit(subreddit_name)
                while True:
                    random_post = subreddit.random()
                    cpid = None
                    if random_post is None:
                        for submission in subreddit.hot():
                            cpid = getattr(submission, 'crosspost_parent', None)
                            if cpid:
                                cpid = cpid[3:]
                            if submission.id in seen_posts or cpid in seen_posts:
                                continue
                            random_post = submission
                            break
                    cpid = getattr(random_post, 'crosspost_parent', None)
                    if cpid:
                        cpid = cpid[3:]
                    if random_post.id in seen_posts or cpid in seen_posts:
                        continue
                    seen_posts.append(cpid or random_post.id)
                    print(random_post.id, random_post.shortlink)
                    to_break = True
                    break
                if to_break:
                    break
            to_break = False
            for _ in range(5):
                try:
                    await _actual_start_post(random_post, send_to_chats)
                except Exception:
                    traceback.print_exc()
                    for i in bot_admins:
                        await client.send_message(i, f'{random_post.id}\n{traceback.format_exc()}', parse_mode=None)
                else:
                    to_break = True
                    break
            if to_break:
                break
        await write_seen_posts()

    async def _start_broadcast(text, file, chats):
        uploaded_files = []
        for i in file or []:
            uploaded_files.append(await client.upload_file(i))
        for chat in chats:
            for i in chunks(zip_longest(text, uploaded_files), 10):
                j, k = zip(*i)
                if not any(k):
                    k = None
                if not k and len(j) == 1:
                    j = j[0]
                await client.send_message(chat, j, file=k)

    async def _download_file(filename, url):
        print(url)
        async with session.get(url) as resp:
            with open(filename, 'wb') as file:
                while True:
                    chunk = await resp.content.read(10)
                    if not chunk:
                        break
                    file.write(chunk)

    async def _get_file_mimetype(filename):
        mimetype = mimetypes.guess_type(filename)[0]
        if not mimetype:
            proc = await asyncio.create_subprocess_exec('file', '--brief', '--mime-type', filename, stdout=asyncio.subprocess.PIPE)
            stdout, _ = await proc.communicate()
            mimetype = stdout.decode().strip()
        return mimetype or ''

    async def _get_file_ext(filename):
        proc = await asyncio.create_subprocess_exec('file', '--brief', '--extension', filename, stdout=asyncio.subprocess.PIPE)
        stdout, _ = await proc.communicate()
        ext = stdout.decode().strip().split('/', maxsplit=1)[0]
        if not ext or ext == '???':
            mimetype = await _get_file_mimetype(filename)
            ext = mimetypes.guess_extension(mimetype) or '.bin'
        if not ext.startswith('.'):
            ext = '.' + ext
        return ext

    async def _actual_start_post(random_post, chats):
        text = f'<a href="{random_post.shortlink}">{html.escape(random_post.title)}</a>'
        cpid = getattr(random_post, 'crosspost_parent', None)
        if cpid and getattr(random_post, 'crosspost_parent_list', None):
            random_post = reddit.submission(cpid[3:])
            text += f' (crosspost of <a href="{random_post.shortlink}">{html.escape(random_post.title)}</a>)'
        if not random_post.is_self:
            with tempfile.TemporaryDirectory() as tempdir:
                url = random_post.url
                filename = os.path.join(tempdir, str(time.time()))
                files = [filename]
                captions = [text]
                if random_post.is_video:
                    ffmpeg_exists = any(True for i in os.environ.get('PATH', '').split(':') if os.path.exists(os.path.join(i, 'ffmpeg')))
                    reddit_video = random_post.secure_media['reddit_video']
                    for i in ('hls_url', 'dash_url'):
                        if not ffmpeg_exists:
                            continue
                        url = reddit_video.get(i)
                        if not url:
                            continue
                        print(url)
                        proc = await asyncio.create_subprocess_exec('ffmpeg', '-nostdin', '-y', '-i', url, '-c', 'copy', '-f', 'mp4', filename)
                        await proc.communicate()
                        if not proc.returncode:
                            url = None
                            break
                    else:
                        url = reddit_video['fallback_url']
                elif getattr(random_post, 'is_gallery', None):
                    files = []
                    captions = []
                    for a, i in enumerate(random_post.media_metadata):
                        captions.append(f'{text}\n#{a + 1}')
                        filename = os.path.join(tempdir, str(time.time()))
                        i = random_post.media_metadata[i]
                        await _download_file(filename, i['s']['u'])
                        files.append(filename)
                    url = None
                if url:
                    parsed = list(urlparse(url))
                    splitted = os.path.splitext(parsed[2])
                    domain = getattr(random_post, 'domain', parsed[1])
                    preview = getattr(random_post, 'preview', None)
                    if domain.endswith('imgur.com'):
                        parsed[1] = 'i.imgur.com'
                        if parsed[2].startswith('/a/'):
                            albumid = os.path.split(parsed[2])[1]
                            async with session.get(f'https://imgur.com/ajaxalbums/getimages/{albumid}/hit.json?all=true') as resp:
                                apidata = (await resp.json())['data']
                            if apidata['count'] == 1:
                                parsed[2] = apidata['images'][0]['hash'] + apidata['images'][0]['ext']
                                desc = apidata['images'][0]['description']
                                if desc:
                                    captions[0] += '\n' + html.escape(desc)
                            else:
                                files = []
                                captions = []
                                for a, i in enumerate(apidata['images']):
                                    to_append = f'{text}\n#{a + 1}'
                                    desc = i['description']
                                    if desc:
                                        to_append += ': ' + html.escape(desc)
                                    captions.append(to_append)
                                    filename = os.path.join(tempdir, str(time.time()))
                                    await _download_file(filename, f'https://i.imgur.com/{i["hash"]}{i["ext"]}')
                                    files.append(filename)
                                url = None
                        if splitted[1] == '.gifv':
                            parsed[2] = splitted[0] + '.mp4'
                        if url:
                            url = urlunparse(parsed)
                    elif domain == 'gfycat.com':
                        async with session.get(f'https://api.gfycat.com/v1/gfycats/{parsed[2]}') as resp:
                            apidata = await resp.json()
                        gfyitem = apidata.get('gfyItem')
                        if gfyitem:
                            url = gfyitem.get('mp4Url', url)
                    elif random_post.is_reddit_media_domain and splitted[1] == '.gif' and preview:
                        preview = preview['images'][0]['variants']
                        for i in ('mp4', 'gif'):
                            if i in preview:
                                url = preview[i]['source']['url']
                                break
                if url:
                    await _download_file(filename, url)
                    mimetype = await _get_file_mimetype(filename)
                    if mimetype.startswith('image') and preview and preview['enabled']:
                        preview = preview['images'][0]
                        urls = [i['url'] for i in preview['resolutions']]
                        urls.append(preview['source']['url'])
                        urls.reverse()
                        for url in urls:
                            if os.path.getsize(filename) < 10000000:
                                break
                            await _download_file(filename, url)
                    ext = await _get_file_ext(filename)
                    if ext.startswith('.htm'):
                        files = []
                        captions = [f'<a href="{url}">{zws}</a>{text}\n\nURL: {url}']
                for a, i in enumerate(files):
                    ext = await _get_file_ext(i)
                    os.rename(i, i + ext)
                    files[a] = i + ext
                await _start_broadcast(captions, files, chats)
        else:
            if getattr(random_post, 'selftext', None):
                caplength = 4094 - len(client.parse_mode.parse(text)[0])
                text += '\n\n'
                captext = random_post.selftext[:caplength]
                if len(captext) >= caplength:
                    captext = captext[:-1]
                    captext += '…'
                text += html.escape(captext)
            await _start_broadcast([text], None, chats)

    def register(pattern):
        def wrapper(func):
            @functools.wraps(func)
            @client.on(events.NewMessage(chats=bot_admins, pattern=pattern))
            async def awrapper(e):
                try:
                    await func(e)
                except Exception:
                    await e.reply(traceback.format_exc(), parse_mode=None)
                    raise
            return awrapper
        return wrapper

    @register('/(start|help)')
    async def start_or_help(e):
        await e.reply(('/start - /help\n'
                       '/help - /start\n'
                       '/poweroff - shuts down bot\n'
                       '/test <submission id> - tests sending submission'), parse_mode=None)

    @register('/poweroff')
    async def poweroff(e):
        await e.reply('ok')
        await e.client.disconnect()

    @register('/test (.+)')
    async def test_post(e):
        await e.reply('ok')
        post = reddit.submission(e.pattern_match.group(1))
        await _actual_start_post(post, [e.chat_id])

#    await start_post.func()
    try:
        await client.run_until_disconnected()
    finally:
        await session.close()

if __name__ == '__main__':
    asyncio.run(main())