from flask import (
    Blueprint, redirect, url_for, flash, render_template, request
    )
from .users import login_required, get_active_user
from ..lib.babycode import babycode_to_html
from ..constants import InfoboxKind
from ..db import db
from ..models import Posts, PostHistory, Threads

bp = Blueprint("posts", __name__, url_prefix = "/post")


def create_post(thread_id, user_id, content, markup_language="babycode"):
    with db.transaction():
        post = Posts.create({
            "thread_id": thread_id,
            "user_id": user_id,
            "current_revision_id": None,
        })

        revision = PostHistory.create({
            "post_id": post.id,
            "content": babycode_to_html(content),
            "is_initial_revision": True,
            "original_markup": content,
            "markup_language": markup_language,
        })

        post.update({"current_revision_id": revision.id})
        return post


def update_post(post_id, new_content, markup_language='babycode'):
    with db.transaction():
        post = Posts.find({'id': post_id})
        new_revision = PostHistory.create({
            'post_id': post.id,
            'content': babycode_to_html(new_content),
            'is_initial_revision': False,
            'original_markup': new_content,
            'markup_language': markup_language,
        })

        post.update({'current_revision_id': new_revision.id})


@bp.post("/<post_id>/delete")
@login_required
def delete(post_id):
    post = Posts.find({'id': post_id})
    thread = Threads.find({'id': post.thread_id})
    user = get_active_user()

    if user.is_mod() or post.user_id == user.id:
        post.delete()
        flash("Post deleted.", InfoboxKind.INFO)

    return redirect(url_for('threads.thread', slug=thread.slug))


@bp.get("/<post_id>/edit")
@login_required
def edit(post_id):
    user = get_active_user()
    q = f"{Posts.FULL_POSTS_QUERY} WHERE posts.id = ?"
    editing_post = db.fetch_one(q, post_id)
    if not editing_post:
        return redirect(url_for('topics.all_topics'))
    if editing_post['user_id'] != user.id:
        return redirect(url_for('topics.all_topics'))

    thread = Threads.find({'id': editing_post['thread_id']})

    thread_predicate = f'{Posts.FULL_POSTS_QUERY} WHERE posts.thread_id = ?'

    context_prev_q = f'{thread_predicate} AND posts.created_at < ? ORDER BY posts.created_at DESC LIMIT 2'
    context_next_q = f'{thread_predicate} AND posts.created_at > ? ORDER BY posts.created_at ASC LIMIT 2'
    prev_context = db.query(context_prev_q, thread.id, editing_post['created_at'])
    next_context = db.query(context_next_q, thread.id, editing_post['created_at'])

    return render_template('posts/edit.html',
                           editing_post = editing_post,
                           thread = thread,
                           prev_context = prev_context,
                           next_context = next_context,
                           )


@bp.post("/<post_id>/edit")
@login_required
def edit_form(post_id):
    user = get_active_user()
    post = Posts.find({'id': post_id})
    if post.user_id != user.id:
        return redirect(url_for('topics.all_topics'))

    update_post(post.id, request.form.get('new_content', default=''))
    thread = Threads.find({'id': post.thread_id})
    return redirect(url_for('threads.thread', slug=thread.slug, after=post.id, _anchor=f'post-{post.id}'))