#!/usr/bin/env python3
"""
A display interface for archived 4chan quest threads.
"""
from collections import defaultdict

from aiohttp import web
import jinja2
import aiohttp_jinja2
from aiohttp_jinja2 import render_template
import asyncpg
import uvloop

import config
import filters

uvloop.install()
routes = web.RouteTableDef()

@routes.get('/', name='index')
async def index(request):
	"""The index page."""
	async with request.app['pool'].acquire() as conn:
		threads = await conn.fetch("SELECT * FROM thread ORDER BY time ASC")
	return render_template("index.html", request, locals())


@routes.get(r'/{thread_id:\d+}', name='thread')
async def thread(request):
	"""A single thread page."""
	thread_id = int(request.match_info['thread_id'])
	async with request.app['pool'].acquire() as conn:
		posts = await conn.fetch(
			"SELECT * FROM post WHERE thread_id = $1 ORDER BY id ASC",
			thread_id)
		tags_raw = await conn.fetch(
			"SELECT tag.post_id, tag.name FROM tag "
			"LEFT JOIN post ON (tag.post_id = post.id) "
			"WHERE post.thread_id = $1",
			thread_id)
		links_raw = await conn.fetch(
			"SELECT link.link_from, link.link_to FROM link "
			"LEFT JOIN post ON (link.link_from = post.id) "
			"WHERE post.thread_id = $1",
			thread_id)
	tags = defaultdict(list)
	links = defaultdict(list)
	backlinks = defaultdict(list)

	for tag_raw in tags_raw:
		tag = tags[tag_raw['post_id']]
		tag.append(tag_raw['name'])
		tags[tag_raw['post_id']] = tag

	for link_raw in links_raw:
		link = links[link_raw['link_from']]
		link.append(link_raw['link_to'])
		links[link_raw['link_from']] = link

		backlink = backlinks[link_raw['link_to']]
		backlink.append(link_raw['link_from'])
		backlinks[link_raw['link_to']] = backlink

	url_prefix = config.url_prefix

	return render_template("thread.html", request, locals())


@routes.post('/add_tag', name='add_tag')
async def add_tag(request):
	"""Adds a tag to a post."""
	data = await request.json()
	post_id = int(data.get('post_id'))
	tag_name = data.get('tag_name')
	async with request.app['pool'].acquire() as conn:
		await conn.execute(
			"INSERT INTO tag (post_id, name) VALUES ($1, $2)",
			post_id, tag_name)
	return web.json_response({'ok': True})


@routes.post('/remove_tag', name='remove_tag')
async def remove_tag(request):
	"""Removes a tag to a post."""
	data = await request.json()
	post_id = int(data.get('post_id'))
	tag_name = data.get('tag_name')
	async with request.app['pool'].acquire() as conn:
		await conn.execute(
			"DELETE FROM tag WHERE post_id = $1 AND name = $2",
			post_id, tag_name)
	return web.json_response({'ok': True})


async def init_app():
	"""Initializes the application."""
	app = web.Application()
	aiohttp_jinja2.setup(
		app,
		trim_blocks=True,
		lstrip_blocks=True,
		undefined=jinja2.StrictUndefined,
		loader=jinja2.FileSystemLoader('templates'),
		filters={
			'quotelink': filters.quotelink,
		},
	)
	app['pool'] = await asyncpg.create_pool(**config.db)

	app.router.add_routes(routes)

	app_wrap = web.Application()
	app_wrap.add_subapp(config.url_prefix, app)
	return app_wrap


if __name__ == "__main__":
	app = init_app()
	web.run_app(app, host='0.0.0.0', port=5450)