#!/usr/bin/env python
from datetime import datetime
from functools import lru_cache
import os
from random import randint

from alchemical import Alchemical
import sqlalchemy as sqla
from cachetools import cached
from cachetools.keys import hashkey

from microdot_wsgi import Microdot
from microdot_jinja import render_template

app = Microdot()
db = Alchemical(os.environ['DATABASE_URL'])


class World(db.Model):
    __tablename__ = "world"
    id = sqla.Column(sqla.Integer, primary_key=True)
    randomnumber = sqla.Column(sqla.Integer)

    def to_dict(self):
        return {"id": self.id, "randomNumber": self.randomnumber}


class CachedWorld(db.Model):
    __tablename__ = "cachedworld"
    id = sqla.Column(sqla.Integer, primary_key=True)
    randomnumber = sqla.Column(sqla.Integer)

    def to_dict(self):
        return {"id": self.id, "randomNumber": self.randomnumber}


class Fortune(db.Model):
    __tablename__ = "fortune"
    id = sqla.Column(sqla.Integer, primary_key=True)
    message = sqla.Column(sqla.String)


def get_num_queries(request, name="queries"):
    try:
        num_queries = request.args.get(name, 1, type=int)
    except ValueError:
        num_queries = 1
    if num_queries < 1:
        return 1
    if num_queries > 500:
        return 500
    return num_queries


def generate_ids(num_queries):
    ids = {randint(1, 10000) for _ in range(num_queries)}
    while len(ids) < num_queries:
        ids.add(randint(1, 10000))
    return list(ids)


@app.route("/json")
def test_json(request):
    return {"message": "Hello, World!"}


@app.route("/db")
def test_db(request):
    id = randint(1, 10000)
    with db.Session() as session:
        world = session.get(World, id)
    return world.to_dict()


@app.route("/queries")
def test_queries(request):
    with db.Session() as session:
        worlds = [session.get(World, id).to_dict() for id in generate_ids(get_num_queries(request))]
    return worlds


@app.route("/fortunes")
def test_fortunes(request):
    with db.Session() as session:
        fortunes = list(session.scalars(Fortune.select()))
    fortunes.append(Fortune(id=0, message="Additional fortune added at request time."))
    fortunes.sort(key=lambda f: f.message)
    return render_template("fortunes.html", fortunes=fortunes), {'Content-Type': 'text/html; charset=utf-8'}


@app.route("/updates")
def test_updates(request):
    worlds = []
    ids = generate_ids(get_num_queries(request))
    ids.sort()  # to avoid deadlocks
    with db.begin() as session:
        for id in ids:
            world = session.get(World, id)
            world.randomnumber = (randint(1, 9999) + world.randomnumber - 1) % 10000 + 1
            worlds.append(world.to_dict())
    return worlds


@app.route("/plaintext")
def test_plaintext(request):
    return b"Hello, World!"


@cached(cache={}, key=lambda session, id: hashkey(id))
def get_cached_world(session, id):
    return session.get(World, id).to_dict()


@app.route("/cached-queries")
def test_cached_queries(request):
    with db.Session() as session:
        worlds = [get_cached_world(session, id) for id in generate_ids(get_num_queries(request, 'count'))]
    return worlds