#!/usr/bin/env python3

import uuid
import sqlite3
from datetime import datetime
from flask import Flask, request, render_template
from flask_uuid import FlaskUUID
from flask_qrcode import QRcode
# TODO: use sockets to broadcast when a hit to the expected uuid has been
# received, so that connected clients (the Chromium public browser) can
# refresh the qr code and update the list of users
# https://flask-socketio.readthedocs.io

app = Flask(__name__)
FlaskUUID(app)
QRcode(app)

def get_db_connection():
    conn = sqlite3.connect('database.db')
    conn.row_factory = sqlite3.Row
    return conn

@app.route('/')
def show_qr_and_list():
    # TODO: reject direct connections to server; allow access only via proxy
    conn = get_db_connection()
    data = conn.execute('SELECT * FROM hits ORDER BY id DESC LIMIT 10').fetchall()
    conn.close()

    # TODO: next_ uuid should be in global state, to verify it when it's received
    return render_template("template.html",
            next_uuid=str(uuid.uuid1()),
            hits=data)

@app.route('/<uuid:id>')
def catch_uuids(id):
    ua = request.headers.get('Remote-User')
    # TODO: Check directly with Authelia using https://auth.agofer.net/api/verify
    time = datetime.now().strftime("%A %Y-%m-%d %H:%M:%S")
    error = None
    data = []
    conn = get_db_connection()
    existing = conn.execute(
            'SELECT * FROM hits WHERE uuid = ?', (str(id),)).fetchone()
    # TODO: verify that the uuid was generated by us (otherwise any uuid,
    # like one generated by the user, would be accepted)
    if not ua:
        error = 'NO_USERNAME'
    elif existing:
        error = 'ALREADY_USED'
    else:
        conn.execute("INSERT INTO hits (uuid, user) VALUES (?, ?)", (str(id), ua))
        conn.commit()
        data = conn.execute(
                'SELECT * FROM hits WHERE user = ? ORDER BY id DESC LIMIT 10', (ua,)
                ).fetchall()
    conn.close()

    return render_template('thanks.html', user=ua, time=time, error=error, hits=data)

if __name__ == '__main__':
    app.run(host='0.0.0.0')