import requests
from flask import Blueprint, render_template, request, flash, g, url_for, redirect
from werkzeug.exceptions import NotFound

from ..common.common import *
from ..common.innertube import *
from .lib import *
from .protobuf import make_sp, make_channel_params, make_playlist_params

frontend = Blueprint('browse', __name__,
    template_folder='templates',
    static_folder='static',
    static_url_path='/static/ys')

@frontend.route('/results')
@frontend.route('/search')
def search():
    #token = getattr(current_user, 'token', 'guest')
    q = request.args.get('q') or request.args.get('search_query')
    page = int(request.args.get('page') or 1)

    sp = make_sp(**{
        k:v for k,v in request.args.items()
        if k in ['sort','date','type','len']
    }, extras=['dont_fix_spelling']*0) # extras disabled

    if q:
        yt_results = fetch_searchresults(q, page, sp)

        results, extras = prepare_searchresults(yt_results)

        for extra in extras:
            flash(extra, 'info')
    else:
        results = None

    return render_template('search.html.j2', rows=results, query=q, page=page)

# TODO: channels, playlists:
# https://github.com/iv-org/invidious/blob/452d1e8307d6344dd51c5437ccd032a566291c34/src/invidious/channels.cr#L399

@frontend.route('/channel/<channel_id>/')
@frontend.route('/channel/<channel_id>/<subpage>')
def channel(channel_id, subpage="videos"):
    if subpage == "videos":
        page = int(request.args.get('page', 1))
        sort_by = request.args.get('sort') or "newest"
        query = None
    elif subpage == "playlists":
        page = None # TODO: cursor
        sort_by = request.args.get('sort', "modified")
        query = None
    elif subpage == "search":
        query = request.args.get('q')
        page = int(request.args.get('page', 1))
        sort_by = None
    else: # we don't support /home, /about, ..., so redirect to /videos.
        return redirect(url_for('.channel', channel_id=channel_id))

    # best effort; if it fails, it fails in the redirect.
    if not re.match(r"(UC[A-Za-z0-9_-]{22})", channel_id):
        return redirect(url_for('.channel_redirect', user=channel_id))

    result = fetch_ajax(make_channel_params(channel_id, subpage, page, sort_by, query))

    # Note: as of 2020-08-15, using the v1 format sometimes returns an error. if that's the case, try v3.
    alert = listget(listget(result,1,{}).get('response',{}).get('alerts',[]),0,{}).get('alertRenderer',{})
    if alert.get('type','') == "ERROR": # alert['text']['simpleText'] == "Unknown error."
        result = fetch_ajax(make_channel_params(channel_id, subpage, page, sort_by, query, v3=True))

    title, descr, thumb, rows, more = prepare_channel(result, channel_id)
    # TODO: add is_pinned/is_hidden

    if title is None: # if both v1 and v3 failed, fall back to xmlfeed:
        flash("unable to fetch results from ajax; displaying fallback results (15 newest)", "error")
        return fallback_route(channel_id, subpage)

    return render_template('channel.html.j2',
        title=title,
        subpage=subpage,
        rows=rows,
        channel_id=channel_id,
        channel_img=thumb,
        channel_desc=descr,
        page=page,
        has_more=more)

@frontend.route('/user/<user>/')
@frontend.route('/user/<user>/<subpage>')
@frontend.route('/c/<user>/')
@frontend.route('/c/<user>/<subpage>')
def channel_redirect(user, subpage=None):
    """
    The browse_ajax 'API' needs the UCID. We can get that from the RSS feeds.
    """

    # inverse of the test in /channel/:
    if re.match(r"(UC[A-Za-z0-9_-]{22})", user):
        return redirect(url_for('.channel', channel_id=user))

    xmlfeed = fetch_xml("user", user)
    if not xmlfeed:
        raise NotFound("channel appears to not exist")
    _, _, _, channel_id, _ = parse_xml(xmlfeed)
    return redirect(
        url_for('.channel', channel_id=channel_id, subpage=subpage), 308
    )

@frontend.route('/playlist')
def playlist():
    #TODO: if anything goes wrong, fall back to xmlfeed
    playlist_id = request.args.get('list')
    if not playlist_id:
        return "bad list id", 400 # todo
    page = int(request.args.get('page', 1))

    xmlfeed = fetch_xml("playlist_id", playlist_id)
    if not xmlfeed:
        return "not found or something", 404 # XXX
    title, author, _, channel_id, _ = parse_xml(xmlfeed)

    offset = (page-1)*100 # each call returns 100 items
    result = fetch_ajax(make_playlist_params(playlist_id, offset))

    if not 'continuationContents' in result[1]['response']: # XXX: this needs cleanup!
        # code:"CONDITION_NOT_MET", debugInfo:"list type not viewable"
        # on playlist https://www.youtube.com/watch?v=6y_NJg-xoeE&list=RDgohHV9ryp-A&index=24 (not openable on yt.com)
        error = result[1]['response']['responseContext']['errors']['error'][0]
        flash(f"{error['code']}: {error['debugInfo'] or error['externalErrorMessage']}", 'error')
        return fallback_route()
    rows, more = prepare_playlist(result)

    return render_template('playlist.html.j2',
        title=title,
        author=author,
        channel_id=channel_id,
        rows=rows,
        page=page,
        has_more=more)

@frontend.before_app_request
def inject_button():
    if not 'header_items' in g:
        g.header_items = []
    g.header_items.append({
        'name': 'search',
        'url': url_for('browse.search'),
        'parent': frontend.name,
        'priority': 15,
    })