import re
import sqlite3
from flask_login import current_user, login_required
from flask import Blueprint, render_template, request, redirect, flash, url_for

from ..common.common import *
from .lib import *

frontend = Blueprint('reddit', __name__,
    template_folder='templates',
    static_folder='static',
    static_url_path='/static/rd')

@frontend.route('/feed/subreddits')
@frontend.route('/r/<subreddit>')
def reddit(subreddit=None):
    token = getattr(current_user, 'token', 'guest')
    count = int(request.args.get('count', 0))
    before = request.args.get('before')
    after = request.args.get('after')

    sortorder = request.args.get('s', "hot") # TODO: verify!
    timerange = request.args.get('t', None) # TODO: verify!

    all_subreddits = get_subreddits(token)
    subreddits = [subreddit] if subreddit else all_subreddits

    try:
        data = fetch_reddit(subreddits,
                sorted_by=sortorder, time=timerange, limit=36,
                count=count, before=before, after=after)
        videos = parse_reddit_videos(data)
        before = data['data']['before']
        after = data['data']['after']
    except RedditException as e:
        return f"error retrieving reddit data: <xmp>{e}</xmp>", 502 # TODO: better

    # set pin/hide stati of retrieved videos
    video_ids = [v['video_id'] for v in videos]
    pinned, hidden = fetch_video_flags(token, video_ids)
    videos = sorted([
        {**v, 'pinned': v['video_id'] in pinned}
        for v in videos
        if v['video_id'] not in hidden
    ], key=lambda v:v['pinned'], reverse=True)

    title = f"/r/{subreddit}" if subreddit else "my subreddits"
    return render_template('reddit.html.j2', title=title, rows=videos,
        subreddits=all_subreddits, before=before, after=after, count=count)

@frontend.route('/manage/subreddits')
# disabled for guest user: @login_required
def subscription_manager():
    token = getattr(current_user, 'token', 'guest')
    subreddits = get_subreddits(token)
    return render_template('subreddit_manager.html.j2', subreddits=subreddits)

@frontend.route('/manage/subreddits', methods=['POST'])
@login_required
def manage_subscriptions():
    token = current_user.token
    if 'subscribe' in request.form:
        subreddit = request.form.get("subscribe")
        match = re.search(r"(?:(?:https?://)?(?:old.|www.|\w\w.)?reddit.com)?(?:/?r/)?([-+_0-9A-Za-z]{2,21})", subreddit)
        if match:
            subreddit = match.group(1)
        else:
            flash("invalid subreddit", "error")
            return redirect(request.url, code=303)
        with sqlite3.connect(cf['global']['database']) as conn:
            c = conn.cursor()
            c.execute("""
			INSERT OR IGNORE INTO subreddits (user, subreddit)
			VALUES (?, ?)
            """, (token, subreddit))

    elif 'unsubscribe' in request.form:
        subreddit = request.form.get("unsubscribe")
        with sqlite3.connect(cf['global']['database']) as conn:
            c = conn.cursor()
            c.execute("""
			DELETE FROM subreddits
			WHERE user = ? AND subreddit = ?
            """, (token, subreddit))
            # TODO: sql-error-handling, report success

    else:
        flash("unsupported action", "error")

    return redirect(request.url, code=303)

def get_subreddits(token):
    with sqlite3.connect(cf['global']['database']) as conn:
        c = conn.cursor()
        c.execute("""
          SELECT subreddit
            FROM subreddits
           WHERE user = ?
        ORDER BY subreddit COLLATE NOCASE ASC
        """, (token,))
        subreddits = [sr for (sr,) in c.fetchall()]
    return subreddits

@frontend.app_template_filter('trim3')
def trim3(n):
    if type(n) != int:
        return n # not a number
    elif round(n, 1) >= 10_000:
        return "%.0fk" % (n/1000)
    elif n >= 1_000:
        return "%.1fk" % (n/1000)
    else:
        return "%d" % n

@frontend.before_app_request
def inject_reddit_button():
    if not 'header_items' in g:
        g.header_items = []
    g.header_items.append({
        'name': 'reddit',
        'url': url_for('reddit.reddit'),
        'parent': frontend.name,
        'priority': 5
    })