const mysql = require('mysql');
const http = require('http');
const express = require('express');
const path = require('path');
const app = express();
const port = 3000;
const sql = mysql.createConnection({
    host: "localhost",
    user: "root",
    password: "root",
    database: "test"
});
const exphbs = require("express-handlebars");
const session = require('express-session');
const bodyParser = require('body-parser');
const crypto = require("crypto");
const request = require("request");

sql.connect(function(err) {
    if (err) throw err;
});

app.use((req, res, next) => {
    res.append('Access-Control-Allow-Origin', ['*']);
    res.append('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE');
    res.append('Access-Control-Allow-Headers', 'Content-Type');
    next();
});
app.use(express.static("css"));
app.use(express.static("js"));
app.use(express.static("views"));
app.use(express.static("fonts"));
app.use(bodyParser.urlencoded({
    extended: true
}));
app.use(bodyParser.json());
app.use(session({
    secret: '_SLgw+8o~sM6a*we`/y5Ag_9q0UgZV=;mW:`Zl)7K]ouxkub1z5?E:<|pQUmjy*',
    resave: true,
    saveUninitialized: false,
    cookie:
    {
        expires: 600000
    }
}));

app.engine("handlebars", exphbs({ defaultLayout: "main", layoutsDir: __dirname + "/views/layouts/" }));
app.set("view engine", "handlebars");
app.set("views", path.join(__dirname, "views"));

app.get("/mysql", (req, res) =>
{
    let query = req.query.query;
    if(!req.session.userid) return res.render("mysql", {deny: "You are not logged in."});
    if(req.session.admin == 0) return res.render("mysql", {deny: "You are not an administrator."});
    if(query === null || query === undefined) return res.render("mysql");
    if(query.length == 0) return res.render("mysql", {error: "The query cannot be empty."});

    sql.query("SELECT * FROM `users` WHERE `Name` LIKE ?", "%" + query + "%", (err, result, fields) =>
    {
        if(err) throw err;
        if(result.length == 0)
        {
            return res.render("mysql", {error: "The query returned nothing.", Query: query});
        }
        let arr = [];
        Object.keys(result).forEach(function(key)
        {
            let row = result[key];
            arr.push({ID: row.ID, Name: row.Name, Email: row.Email, Created: row.Created});
        });

        let data =
        {
            items: arr,
            Query: query
        }
        res.render("mysql", data);
    });

});

app.get("/", (req, res) =>
{
    res.render("home");
});

app.get("/login", (req, res) =>
{
    /*console.log(res.statusCode);
    console.log(req.statusCode);
    if(res.statusCode == 401) return res.render("login", {error: "You have to login first."});*/
    if(req.session.userid) return res.render("login", {deny: "You are already logged in."});
    if(req.query.name === undefined || req.query.name === null) return res.render("login");
    const hash = crypto.createHash("sha256");
    hash.update(req.query.password);
    let password = hash.digest("hex");
    if(req.query.name.length == 0 || req.query.password.length == 0) return res.render("login", {error: "The name or password cannot be empty.", name: req.query.name, password: req.query.password});
    sql.query('SELECT * FROM `users` WHERE `Name` = ? AND BINARY `Password` = ?', [req.query.name, password], (error, result, fields) =>
    {
        if(error) throw error;
        if(result.length == 0)
        {
            return res.render("login", {error: "The account does not exist or the wrong password was specified.", name: req.query.name, password: req.query.password});
        }
        let ses = req.session;
        ses.userid = result[0].ID;
        ses.admin = result[0].Admin;
        ses.email = result[0].Email;
        ses.name = result[0].Name;
        res.render("login", {success: 1, email: result[0].Email, created: result[0].Created, name: req.query.name, password: req.query.password});
    });
});

app.get("/register", (req, res) =>
{
    if(req.session.userid) return res.render("register", {deny: "You are already logged in."});
    if(req.query.name === undefined || req.query.name === null) return res.render("register");
    if(req.query.name.length == 0 || req.query.password.length == 0 || req.query.email.length == 0) return res.render("register", {error: "The name, password or email cannot be empty.", name: req.query.name, password: req.query.password, email: req.query.email});
    if(req.query.password.length < 4) return res.render("register", {error: "The password has to be atleast 4 characters long.", name: req.query.name, password: req.query.password, email: req.query.email});
    if(req.query.name.length < 4) return res.render("register", {error: "The name has to be atleast 4 characters long.", name: req.query.name, password: req.query.password, email: req.query.email});
    if(req.query.email.length < 6) return res.render("register", {error: "The email has to be atleast 6 characters long.", name: req.query.name, password: req.query.password, email: req.query.email});
    if(req.query.password.length > 64) return res.render("register", {error: "The password has to be max 64 characters long.", name: req.query.name, password: req.query.password, email: req.query.email});
    if(req.query.name.length > 32) return res.render("register", {error: "The name has to be max 32 characters long.", name: req.query.name, password: req.query.password, email: req.query.email});
    if(req.query.email.length > 64) return res.render("register", {error: "The email has to be max 64 characters long.", name: req.query.name, password: req.query.password, email: req.query.email});
    sql.query("SELECT * FROM `users` WHERE `Name` = ?", req.query.name, (error, result, fields) =>
    {
        if(result.length != 0)
        {
            return res.render("register", {error: "An account with this name already exists.",name: req.query.name, password: req.query.password, email: req.query.email});
        }
        let today = new Date();
        const hash = crypto.createHash("sha256");
        hash.update(req.query.password);
        let password = hash.digest("hex");
        sql.query('INSERT INTO `users` (Name, Password, Email, Created) VALUES (?, ?, ?, ?)', [req.query.name, password, req.query.email, today], (error, result, fields) =>
        {
            if(error) throw error;
            res.render("register", {success: 1, name: req.query.name});
        });
    });
});

app.get("/account", (req, res) =>
{
    console.log(req.url);
    console.log("Test");
    if(req.query.logout)
    {
        if(req.session.userid)
        {
            req.session.destroy();
            return res.render("account", {msg: "You are now logged out."});
        }
        else
        {
           return res.status(401).location('/login');
        }
    }
    if(!req.session.userid)
    {
       return res.status(401).location('/login');
    }
    res.render("account");
});

app.use((req, res, next) =>
{
    res.status(404);
    res.render("404", {url: req.url});
});

app.listen(port);
console.log("Der Hauptserver wurde erfolgreich gestartet!");