// Express Vars
const express = require('express');
const app = express();
const port = 3000;

app.use(express.json());       // to support JSON-encoded bodies
app.use(express.urlencoded()); // to support URL-encoded bodies

// Node Vars
const fs = require("fs");

// Local imports
const { fetchURL } = require('./fetch');
const { steam_key, app_id, results } = require('./config.json');
const { download } = require('./mod_manager');

// Make sure config vars are filled out
if (!steam_key || !app_id) {
    console.log("You need to fill out either your Steam Key or your App ID in the config.json");
    return;
}

// Express Routing
app.get('/mods', async (req, res) => {
    let html = await createHTML();
    res.send(html);
})

// Take a look into callback functions
app.post('/download', async (req, res) => {
    console.log(req.body);
    await dl_status({published_file_id: req.body.file_id, name: req.body.name, updated: req.body.updated}, res, display_status);

})

app.listen(port, () => {
  console.log(`Example app listening on port ${port}`)
})

// Local Functions
async function createHTML() {
    let details = await fetchURL(steam_key, 'https://api.steampowered.com/IPublishedFileService/QueryFiles/v1/?', app_id, results, 1);
    let template = function(title, image, description, link, updated) {
        let idIndex = link.indexOf("?id=");
        return `<div>` +
                    `<a href='${link}'>` +
                       `<img src='${image}' alt='' width='250px'>` +
                        `<p>${title}</p>` +
                    `</a>` +
                    `<form action='/download' method='post'>` +
                        `<input type='hidden' name='name' value='${title}'>` +
                        `<input type='hidden' name='updated' value='${updated}'>` +
                        `<input type='hidden' name='file_id' value='${link.substring(idIndex + 4, link.length)}'>` +
                        `<input type='submit' value='Download' "> ` +
                    `</form>` +
                `</div>`

    }

    let html = "";
    for (const file in details.response.publishedfiledetails) {
        const element = details.response.publishedfiledetails[file];

        html += template(
            element.title,
            element.preview_url,
            element.short_description,
            `https://steamcommunity.com/sharedfiles/filedetails/?id=${element.publishedfileid}`,
            element.time_updated
        )
    }
    return html;
}

async function dl_status({published_file_id, name, updated}, res, _callback) {
    console.log("Promise Created...");
    let dl_promise = await new Promise(async (resolve, reject) => {
        let code = download({published_file_id: published_file_id, name: name, updated: updated});
        if (code != null) {
            resolve(code);
        } else {
            reject("Error");
        }
    }).then((value) => {
        console.log("Value:");
        console.log(value);
        _callback(value, res);
    }).catch((error) => {
        console.log("Error:");
        console.log(error);
    });
}

async function display_status(code, res) {
    if (code == -1) {
        res.send("Strange error, please report what you did on github or to Thatguy553!");
    } else if (code == -2) {
        res.send("Download Failed, make sure you have internet and SteamCMD downloaded with the path to the executable in the config.json");
    } else if (code == -3) {
        res.send("Download Successful, Couldnt move the mod into game folder. Check SteamCMD/steamapps/common/content/game_id to move the mod manually.");
    } else if (code == -4) {
        res.send("Download Successful, Couldnt move the mod into game folder. This mod already exists in your game folder, instead move to update tab.");
    } else if (code == 1) {
        res.send("Download and Move successful, check your mod folder to confirm!");
    } else if (code == 0) {
        res.send("Strange error, please report what you did on github or to Thatguy553");
    }
}