from flask import Blueprint, redirect, url_for, render_template, request, abort
from functools import wraps
from ..auth import login_required, get_active_user
from ..models import Threads, Posts, Topics, Users, Reactions, Subscriptions
from ..util import get_form_checkbox, time_now
import math

bp = Blueprint('threads', __name__, url_prefix='/threads/')

def ownership_or_mod_required(view_func):
    @wraps(view_func)
    def wrapper(*args, **kwargs):
        thread = Threads.find({'id': kwargs.get('thread_id', None)})
        if not thread:
            abort(404)

        if thread.user_id != get_active_user().id and not get_active_user().is_mod():
            abort(403)

        return view_func(*args, **kwargs)
    return wrapper

@bp.get('/<int:thread_id>/')
def thread_by_id(thread_id):
    thread = Threads.find({'id': thread_id})
    if not thread:
        abort(404)
    return redirect(url_for('.thread', thread_id=thread_id, slug=thread.slug, **request.args))

@bp.get('/<int:thread_id>/<slug>/')
def thread(thread_id, slug):
    thread = Threads.find({'id': thread_id})
    if not thread:
        abort(404)
    if thread.slug != slug:
        return redirect(url_for('.thread', thread_id=thread_id, slug=thread.slug, **request.kwargs))

    topic = Topics.find({'id': thread.topic_id})
    started_by = Users.find({'id': thread.user_id})
    PER_PAGE = 10
    posts_count = Posts.count({'thread_id': thread.id})
    page_count = max(1, math.ceil(posts_count / PER_PAGE))
    page = 1
    after = request.args.get('after')
    if after is not None:
        try:
            after_id = int(after)
            post_position = Posts.count([
                ('thread_id', '=', thread.id),
                ('id', '<=', after_id),
            ])
            page = math.ceil((post_position) / PER_PAGE)
        except ValueError:
            abort(404)
    else:
        try:
            page = max(1, min(int(request.args.get('page', default=1)), page_count))
        except ValueError:
            abort(404)
    posts = thread.get_posts(PER_PAGE, page)
    last_post = posts[-1]
    return render_template(
        'threads/thread.html', thread=thread,
        posts=posts, page=page,
        page_count=page_count, topic=topic,
        started_by=started_by, topics=Topics.get_list(),
        Reactions=Reactions, last_post=last_post
        )

@bp.post('/<int:thread_id>/')
@login_required
def reply(thread_id):
    user = get_active_user()
    thread = Threads.find({'id': thread_id})
    if not thread:
        abort(404)
    if not user.can_post_to_thread_or_topic(thread):
        return redirect(url_for('.thread_by_id', thread_id=thread_id))
    post = Posts.new(user.id, thread.id, request.form.get('babycode_content'))
    if get_form_checkbox('subscribe'):
        if not Subscriptions.find({'user_id': user.id, 'thread_id': thread.id}):
            Subscriptions.create({
                'user_id': user.id,
                'thread_id': thread.id,
                'last_seen': time_now(),
                })
    return redirect(url_for('.thread_by_id', thread_id=thread_id, after=post.id, _anchor=f'post-{post.id}'))

@bp.get('/<int:thread_id>/edit/')
@login_required
@ownership_or_mod_required
def edit(thread_id):
    thread = Threads.find({'id': thread_id})
    if not thread:
        abort(404)
    return render_template('threads/edit.html', thread=thread)

@bp.post('/<int:thread_id>/edit/')
@login_required
@ownership_or_mod_required
def edit_post(thread_id):
    thread = Threads.find({'id': thread_id})
    if not thread:
        abort(404)
    new_title = request.form.get('title', '').strip()
    if not new_title:
        abort(400)

    if new_title != thread.title:
        thread.update({'title': new_title})

    return redirect(url_for('.thread_by_id', thread_id=thread_id))

@bp.post('/<int:thread_id>/subscribe/')
@login_required
def subscribe(thread_id):
    thread = Threads.find({'id': thread_id})
    if not thread:
        abort(404)

    user = get_active_user()
    last_post_id = request.form.get('last_post_id', None)
    if last_post_id is None:
        abort(400)

    if user.is_subscribed(thread_id):
        return redirect(url_for('.thread_by_id', thread_id=thread_id, after=last_post_id))

    Subscriptions.create({
        'user_id': user.id,
        'thread_id': thread_id,
        'last_seen': request.form.get('last_post_timestamp', time_now())
        })

    return redirect(url_for('.thread_by_id', thread_id=thread_id, after=last_post_id))

@bp.post('/<int:thread_id>/unsubscribe/')
@login_required
def unsubscribe(thread_id):
    thread = Threads.find({'id': thread_id})
    if not thread:
        abort(404)

    user = get_active_user()
    last_post_id = request.form.get('last_post_id', None)
    if last_post_id is None:
        abort(400)

    subscription = Subscriptions.find({'user_id': user.id, 'thread_id': thread_id})
    if not subscription:
        return redirect(url_for('.thread_by_id', thread_id=thread_id, after=last_post_id))

    subscription.delete()
    return redirect(url_for('.thread_by_id', thread_id=thread_id, after=last_post_id))

@bp.get('/<int:thread_id>/feed.atom/')
def feed(thread_id):
    return 'stub'

@bp.get('/new/')
@login_required
def new():
    topics = Topics.select()
    try:
        selected_topic = int(request.args.get('topic_id'))
    except ValueError, TypeError:
        selected_topic = None
    return render_template('threads/new_thread.html', topics=topics, selected_topic=selected_topic)

@bp.post('/new/')
@login_required
def new_post():
    try:
        topic_id = int(request.form.get('topic_id'))
    except ValueError, TypeError:
        abort(404)
    topic_id = int(topic_id)
    topic = Topics.find({'id': topic_id})
    if not topic:
        abort(404)

    user = get_active_user()
    if not user.can_post_to_thread_or_topic(topic):
        abort(403)

    title = request.form.get('title', '').strip()
    if not title:
        abort(400)

    title = title.strip()

    content = request.form.get('babycode_content')

    thread = Threads.new(user.id, topic.id, title, content)
    return redirect(url_for('.thread_by_id', thread_id=thread.id))