const fs = require("fs"),
      config = require("../config/config.json"),
      chalk = require("chalk"),
      busboy = require("connect-busboy"),
      randomstring = require("randomstring"),
      getSize = require('get-folder-size'),
      emoji = require("../misc/emoji_list.json");

// Defines the function of this module
const MODULE_FUNCTION = "handle_requests",

      // Base path for module folder creation and navigation
      BASE_PATH = "/EUS";

let eusConfig = {},
    image_json = {},
    d = new Date(),
    startTime,
    endTime;

// Only ran on startup so using sync functions is fine
// Makes the folder for files of the module
if (!fs.existsSync(__dirname + BASE_PATH)) {
    fs.mkdirSync(__dirname + BASE_PATH);
    console.log(`[EUS] Made EUS module folder`);
}
// Makes the folder for frontend files
if (!fs.existsSync(__dirname + BASE_PATH + "/files")) {
    fs.mkdirSync(__dirname + BASE_PATH + "/files");
    console.log(`[EUS] Made EUS web files folder`);
}
// Makes the folder for images
if (!fs.existsSync(__dirname + BASE_PATH + "/i")) {
    fs.mkdirSync(__dirname + BASE_PATH + "/i");
    console.log(`[EUS] Made EUS images folder`);
}
// Makes the image-type file
fs.access(`${__dirname}${BASE_PATH}/image-type.json`, error => {
    if (error) {
        // Doesn't exist, create it.
        fs.writeFile(`${__dirname}${BASE_PATH}/image-type.json`, '{\n}', function(err) {
            if (err) throw err;
            global.modules.consoleHelper.printInfo(emoji.heavy_check, "Created image-type File!");
            // File has been created, load it.
            image_json = require(`${__dirname}${BASE_PATH}/image-type.json`);
        });
    } else {
        // File already exists, load it.
        image_json = require(`${__dirname}${BASE_PATH}/image-type.json`);
    }
});
// Makes the config file
fs.access(`${__dirname}${BASE_PATH}/config.json`, error => {
    if (error) {
        // Config doesn't exist, make it.
        fs.writeFile(`${__dirname}${BASE_PATH}/config.json`, '{\n\t"baseURL":"http://example.com",\n\t"acceptedTypes": [\n\t\t".png",\n\t\t".jpg",\n\t\t".jpeg",\n\t\t".gif"\n\t]\n}', function(err) {
            if (err) throw err;
            global.modules.consoleHelper.printInfo(emoji.heavy_check, "Created config File!");
            global.modules.consoleHelper.printInfo(emoji.wave, "Please edit the EUS Config file before restarting.");
            // Config has been made, close framework.
            process.exit(0);
        });
    } else {
        eusConfig = require(`${__dirname}${BASE_PATH}/config.json`);
    }
});

module.exports = {
    extras:function() {
        // Setup express to use busboy
        global.app.use(busboy());
    },
    get:function(req, res) {
        /*
            req - Request from client
            res - Response from server
        */
        
        // Set some headers
        res.set("Strict-Transport-Security", "max-age=31536000; includeSubDomains");
        res.set("X-XSS-Protection", "1; mode=block");
        res.set("Feature-Policy", "fullscreen 'none'");
        res.set("Referrer-Policy", "strict-origin-when-cross-origin");
        res.set("Content-Security-Policy", "block-all-mixed-content;frame-ancestors 'self'");
        res.set("X-Frame-Options", "SAMEORIGIN");
        res.set("X-Content-Type-Options", "nosniff");

        // Check if returned value is true.
        if (!req.url.includes("/api/")) {
            // Register the time at the start of the request
            d = new Date();
            startTime = d.getTime();
            // Get the requested image
            let urs = ""+req.url; urs = urs.split("/")[1];
            // Get the file type of the image from image_json and make sure it exists
            fs.access(__dirname + BASE_PATH + "/i/"+urs+image_json[urs], error => {
                if (error) {
                    // Doesn't exist, handle request normaly
                    if (req.url === "/") { urs = "/index.html" } else { urs = req.url };
                    fs.access(__dirname + BASE_PATH + "/files"+urs, error => {
                        if (error) {
                            // Doesn't exist, send a 404 to the client.
                            res.status(404).end("404!");
                            d = new Date();
                            endTime = d.getTime();
                            global.modules.consoleHelper.printInfo(emoji.cross, `${req.method}: ${chalk.red("[404]")} ${req.url} ${endTime - startTime}ms`);
                        } else {
                            // File does exist, send it back to the client.
                            res.sendFile(__dirname + BASE_PATH + "/files"+req.url);
                            d = new Date();
                            endTime = d.getTime();
                            global.modules.consoleHelper.printInfo(emoji.heavy_check, `${req.method}: ${chalk.green("[200]")} ${req.url} ${endTime - startTime}ms`);
                        }
                    });
                } else {
                    // Image does exist, send it back.
                    res.sendFile(__dirname + BASE_PATH + "/i/"+urs+image_json[urs]);
                    d = new Date();
                    endTime = d.getTime();
                    global.modules.consoleHelper.printInfo(emoji.heavy_check, `${req.method}: ${chalk.green("[200]")} ${req.url} ${endTime - startTime}ms`);
                }
            });
        } else {
            return handleAPI(req, res);
        }
    },
    post:function(req, res) {
        /*
            req - Request from client
            res - Response from server
        */

        // Make sure the endpoint is /upload
        // If it isn't upload send an empty response
        if (req.url != "/upload") return res.end("");

        // Get time at the start of upload
        d = new Date(); startTime = d.getTime();
        var fstream;
        var thefe;
        // Pipe the request to busboy
        req.pipe(req.busboy);
        req.busboy.on('file', function (fieldname, file, filename) {
            // Get the image-type json
            image_json = require(`${__dirname}${BASE_PATH}/image-type.json`);
            // Make a new file name
            fileOutName = randomstring.generate(14);
            global.modules.consoleHelper.printInfo(emoji.fast_up, `${req.method}: Upload of ${fileOutName} started.`);
            // Check the file is within the accepted file types  
            if (eusConfig.acceptedTypes.includes(`.${filename.split(".")[filename.split(".").length-1]}`)) {
                // File is accepted, set the extention of the file in thefe for later use.
                thefe = `.${filename.split(".")[filename.split(".").length-1]}`;
            } else {
                // File isn't accepted, send response back to client stating so.
                res.end("This file type isn't accepted currently.");
                return;
            }
            // Create a write stream for the file
            fstream = fs.createWriteStream(__dirname + BASE_PATH + "/i/" + fileOutName + thefe);
            file.pipe(fstream);
            fstream.on('close', function () {
                // Get the time at the end of the upload
                d = new Date(); endTime = d.getTime();
                // Add image file type to the image_json array
                image_json[fileOutName] = `.${filename.split(".")[filename.split(".").length-1]}`;
                // Save image_json array to the file
                fs.writeFile(`${__dirname}${BASE_PATH}/image-type.json`, JSON.stringify(image_json), function(err) {
                    if (err) throw err;
                    global.modules.consoleHelper.printInfo(emoji.heavy_check, `${req.method}: Upload of ${fileOutName} finished. Took ${endTime - startTime}ms`);
                    // Send URL of the uploaded image to the client           
                    res.end(eusConfig.baseURL+""+fileOutName);
                });
            });
        });
    }
}

function handleAPI(req, res) {

    // Status check for ESL to make sure EUS is online
    if (req.query["stat"] == "get") return res.end('{ "status":1, "version":"'+global.internals.version+'" }');

    /*  Stats api endpoint
        Query inputs
          f : Values [0,1]
          s : Values [0,1]
    */
    if (req.url.split("?")[0] == "/api/get-stats") {
        const filesaa = req.query["f"],
        spaceaa = req.query["s"];
        let jsonaa = {};
        // If total files is asked for
        if (filesaa == 1) {
            let total = 0;
            jsonaa["files"] = {};
            // Add each accepted file type to the json
            for (var i2 = 0; i2 < eusConfig.acceptedTypes.length; i2++) {
                jsonaa["files"][`${eusConfig.acceptedTypes[i2]}`.replace(".", "")] = 0;
            }
            // Read all files from the images directory
            fs.readdir(__dirname + BASE_PATH + "/i", (err, files) => {
                if (err) throw err;
                // Loop through all files
                for (var i = 0; i < files.length; i++) {
                    // Loop through all accepted file types to check for a match
                    for (var i1 = 0; i1 < eusConfig.acceptedTypes.length; i1++) {
                        const jsudfg = files[i].split(".");
                        if (`.${jsudfg[jsudfg.length-1]}` == eusConfig.acceptedTypes[i1]) {
                            // There is a match! Add it to the json
                            jsonaa["files"][eusConfig.acceptedTypes[i1].replace(".", "")]++;
                            // Also increase the total
                            total++;
                        }
                    }
                }
                // Set the total in the json to the calculated total value
                jsonaa["files"]["total"] = total;

                // If getting the space used on the server isn't required send the json
                if (spaceaa != 1) return res.end(JSON.stringify(jsonaa));
            });
        }
        // Getting space is required
        if (spaceaa == 1) {
            jsonaa["space"] = {};
            // Get the space used on the disk
            getSize(__dirname + BASE_PATH + "/i", (err, size) => {
                if (err) throw err;
                // Calculate in different units the space taken up on disk
                let sizeOfFolder = (size / 1024 / 1024);
                jsonaa["space"]["mb"] = sizeOfFolder;
                sizeOfFolder = (size / 1024 / 1024 / 1024);
                jsonaa["space"]["gb"] = sizeOfFolder;
                sizeOfFolder = (size / 1024 / 1024 / 1024).toFixed(2);
                jsonaa["space"]["string"] = `${sizeOfFolder} GB`;
                // Send the json to the requesting client
                return res.end(JSON.stringify(jsonaa));
            });
        }
    }

    // Information API
    if (req.url.split("?")[0] == "/api/get-info") {
        let jsonaa = {
            version: global.internals.version,
            instance: config["server"]["instance_type"]
        };
        return res.end(JSON.stringify(jsonaa));
    }
}

module.exports.MOD_FUNC = MODULE_FUNCTION;