from flask import (
    Blueprint, render_template, request, redirect, url_for, flash
    )
from .users import login_required, mod_only, get_active_user, is_logged_in
from ..db import db
from ..models import Threads, Topics, Posts, Subscriptions
from ..constants import InfoboxKind
from .posts import create_post
from slugify import slugify
import math
import time

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


@bp.get("/<slug>")
def thread(slug):
    POSTS_PER_PAGE = 10
    thread = Threads.find({"slug": slug})
    if not thread:
        return "no"

    post_count = Posts.count({"thread_id": thread.id})
    page_count = max(math.ceil(post_count / POSTS_PER_PAGE), 1)

    page = 1
    after = request.args.get("after", default=None)
    if after is not None:
        after_id = int(after)
        post_position = Posts.count([
            ("thread_id", "=", thread.id),
            ("id", "<=", after_id),
        ])
        page = math.ceil((post_position) / POSTS_PER_PAGE)
    else:
        page = max(1, min(page_count, int(request.args.get("page", default = 1))))

    posts = thread.get_posts(POSTS_PER_PAGE, (page - 1) * POSTS_PER_PAGE)
    topic = Topics.find({"id": thread.topic_id})
    other_topics = Topics.select()

    is_subscribed = False
    if is_logged_in():
        subscription = Subscriptions.find({
            'thread_id': thread.id,
            'user_id': get_active_user().id,
        })
        if subscription:
            if int(posts[-1]['created_at']) > int(subscription.last_seen):
                subscription.update({
                    'last_seen': int(posts[-1]['created_at'])
                })
            is_subscribed = True

    return render_template(
        "threads/thread.html",
        thread = thread,
        current_page = page,
        page_count = page_count,
        posts = posts,
        topic = topic,
        topics = other_topics,
        is_subscribed = is_subscribed,
    )


@bp.post("/<slug>")
@login_required
def reply(slug):
    thread = Threads.find({"slug": slug})
    if not thread:
        return "no"
    user = get_active_user()
    if user.is_guest():
        return "no"
    if thread.locked() and not user.is_mod():
        return "no"

    post_content = request.form['post_content']
    post = create_post(thread.id, user.id, post_content)

    subscription = Subscriptions.find({'user_id': user.id, 'thread_id': thread.id})

    if subscription:
        subscription.update({'last_seen': int(time.time())})
    elif request.form.get('subscribe', default=None) == 'on':
        Subscriptions.create({'user_id': user.id, 'thread_id': thread.id, 'last_seen': int(time.time())})

    return redirect(url_for(".thread", slug=slug, after=post.id, _anchor="latest-post"))


@bp.get("/create")
@login_required
def create():
    all_topics = Topics.select()
    return render_template("threads/create.html", all_topics = all_topics)


@bp.post("/create")
@login_required
def create_form():
    topic = Topics.find({"id": request.form['topic_id']})
    user = get_active_user()
    if not topic:
        return "no"

    if topic.is_locked and not get_active_user().is_mod():
        return "no"

    title = request.form['title'].strip()
    now = int(time.time())
    slug = f"{slugify(title)}-{now}"

    post_content = request.form['initial_post']
    thread = Threads.create({
        "topic_id": topic.id,
        "user_id": user.id,
        "title": title,
        "slug": slug,
        "created_at": now,
    })
    post = create_post(thread.id, user.id, post_content)
    return redirect(url_for(".thread", slug = thread.slug))


@bp.post("/<slug>/lock")
@login_required
def lock(slug):
    user = get_active_user()
    thread = Threads.find({'slug': slug})
    if not ((thread.user_id == user.id) or user.is_mod()):
        return 'no'
    target_op = request.form.get('target_op')
    thread.update({
        'is_locked': target_op
    })
    return redirect(url_for('.thread', slug=slug))


@bp.post("/<slug>/sticky")
@login_required
@mod_only(".thread", slug = lambda slug: slug)
def sticky(slug):
    user = get_active_user()
    thread = Threads.find({'slug': slug})
    if not ((thread.user_id == user.id) or user.is_mod()):
        return 'no'
    target_op = request.form.get('target_op')
    thread.update({
        'is_stickied': target_op
    })
    return redirect(url_for('.thread', slug=slug))


@bp.post("/<slug>/move")
@login_required
@mod_only(".thread", slug = lambda slug: slug)
def move(slug):
    user = get_active_user()

    new_topic_id = request.form.get('new_topic_id', default=None)
    if new_topic_id is None:
        flash('Thread is already in this topic.', InfoboxKind.ERROR)
        return redirect(url_for('.thread', slug=slug))

    new_topic = Topics.find({
        'id': new_topic_id
    })
    if not new_topic:
        return 'no'
    thread = Threads.find({
        'slug': slug
    })
    if not thread:
        return 'no'
    if new_topic.id == thread.topic_id:
        flash('Thread is already in this topic.', InfoboxKind.ERROR)
        return redirect(url_for('.thread', slug=slug))

    old_topic = Topics.find({'id': thread.topic_id})
    thread.update({'topic_id': new_topic_id})
    flash(f'Topic moved from "{old_topic.name}" to "{new_topic.name}".', InfoboxKind.INFO)
    return redirect(url_for('.thread', slug=slug))


@bp.post("/<slug>/subscribe")
@login_required
def subscribe(slug):
    user = get_active_user()
    thread = Threads.find({'slug': slug})
    if not thread:
        return 'no'
    subscription = Subscriptions.find({
        'user_id': user.id,
        'thread_id': thread.id,
    })
    if request.form['subscribe'] == 'subscribe':
        if subscription:
            subscription.delete()
        Subscriptions.create({
            'user_id': user.id,
            'thread_id': thread.id,
            'last_seen': int(time.time()),
        })
    elif request.form['subscribe'] == 'unsubscribe':
        if not subscription:
            return 'no'
        subscription.delete()
    elif request.form['subscribe'] == 'read':
        if not subscription:
            return 'no'
        subscription.update({
            'last_seen': int(time.time())
        })
    last_visible_post = request.form.get('last_visible_post', default=None)
    if last_visible_post is not None:
        return redirect(url_for('.thread', slug=thread.slug, after=last_visible_post))
    else:
        return redirect(url_for('users.inbox', username=user.username))