#
# YouTube video info command
#
# Copyright © 2023 by luk3yx
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.
#

import math, requests, random, time, traceback


# Default values so that the command still works if api.invidious.io is down
cache_expiry = -math.inf
instances = ['yewtu.be']
api_instances = ['i.psf.lt']


def fetch_instances(irc, args):
    global cache_expiry, instances, api_instances

    # Refresh the cache at most once per day
    if time.monotonic() >= cache_expiry or not instances or not api_instances:
        try:
            resp = requests.get('https://api.invidious.io/instances.json')
            resp.raise_for_status()

            new_instances = []
            new_api_instances = []
            for _, info in resp.json():
                if (info['type'] != 'https' or not info.get('stats') or
                        not info['stats'].get('openRegistrations')):
                    continue

                new_instances.append(info['uri'])
                if info['api']:
                    new_api_instances.append(info['uri'])

            if new_instances and new_api_instances:
                cache_expiry = time.monotonic() + 86400
                instances = new_instances
                api_instances = new_api_instances
        except (requests.RequestException, IndexError, ValueError) as exc:
            # This is okay, just use the cache for now
            traceback.print_exc()
            irc.notice(args[0], f'{exc.__class__.__name__} when fetching '
                       f'Invidious instance list, using cache.')

    return instances, api_instances


RED = '\x0304'
GREEN = '\x0303'


def get_url_and_metadata(irc, args, video_id):
    instances, api_instances = fetch_instances(irc, args)
    api_url = f'{random.choice(api_instances)}'
    res = requests.get(f'{api_url}/api/v1/videos/{video_id}', params={
        'fields': 'title,liveNow,lengthSeconds,author,publishedText,error'
    })
    return f'{random.choice(instances)}/watch?v={video_id}', res.json()


def format_length(seconds):
    minutes = seconds // 60
    seconds %= 60
    if minutes < 60:
        return f'{minutes}:{seconds:02}'
    return f'{minutes // 60}:{minutes % 60:02}:{seconds % 60:02}'


def num(n):
    precision = 0
    for prefix in ('', ' K', ' M'):
        if n < 1000:
            return f'\x02{n:.{precision}f}{prefix}\x02'
        n /= 1000
        precision = 1
    return f'\x02{n:.{precision}f} B\x02'


@register_command('yt', 'youtube')
def youtube(irc, hostmask, is_admin, args):
    video_url = args[1]
    if 'v=' in video_url:
        video_id = video_url.split('v=', 1)[1]
    elif '/shorts/' in video_url:
        video_id = video_url.split('/shorts/', 1)[1]
    elif video_url.startswith(('youtu.be/', 'https://youtu.be/',
                               'http://youtu.be/')):
        video_id = video_url.split('youtu.be/', 1)[1]
    else:
        irc.msg(args[0], 'Usage: .yt <video URL>')
        return
    video_id = video_id.split('?', 1)[0].split('&', 1)[0].split('#', 1)[0]
    res = requests.get('https://returnyoutubedislikeapi.com/votes',
                       params={'videoId': video_id})
    if res.status_code in (400, 404):
        irc.msg(args[0], 'Invalid video ID!')
        return
    res.raise_for_status()
    data = res.json()

    url, md = get_url_and_metadata(irc, args, video_id)
    ok = not md or 'error' not in md

    if video_id == 'dQw4w9WgXcQ':
        md['title'] = 'Normal video'
        md['author'] = 'Definitely not Rick Astley'

    parts = []
    if ok:
        parts.append(md['title'])
        if md['liveNow']:
            parts.append(f'{RED}\x02• Live now\x02')
        else:
            parts.append(format_length(md['lengthSeconds']))
        parts.append(f'Channel: {md["author"]}')
    else:
        error_msg = md.get("error", "Unknown error")
        if error_msg == "Sign in if you've been granted access to this video":
            error_msg = 'The video has been made private'
        parts.append(f'Could not fetch video metadata: {error_msg}')
    parts.append(f'Views: {num(data["viewCount"])}')
    if ok and not md['liveNow']:
        parts.append(f'Published {md["publishedText"]}')
    parts.append(f'Likes: {GREEN}{num(data["likes"])}')
    parts.append(f'Dislikes: {RED}{num(data["dislikes"])}\x03 '
                 f'(from returnyoutubedislike.com)')
    if ok:
        parts.append(f'Link: {url}')

    msg = ' | '.join(part + '\x03' if '\x03' in part else part
                     for part in parts)
    irc.msg(args[0], hostmask[0] + ': ' + msg)