//Get required packages
const electron = require('electron');
const path = require('path');
const url = require('url');
const fs = require('fs');
const asn1js = require('asn1js');
const util = require('util');
const notifier = require('node-notifier');
const smartcard = require('smartcard');

const {
  app,
  BrowserWindow,
  Menu,
  ipcMain
} = electron;

const Devices = smartcard.Devices;
const devices = new Devices();
const Iso7816Application = smartcard.Iso7816Application;

let mainWindow;
let AddWindow;
let AddClassesWindow;
let SelectClassesWindow;

var current_classes = -1;


//Listen for the app to be ready
app.on('ready', function () {
  //Create new window
  mainWindow = new BrowserWindow({
    width: 500,
    height: 600,
	webPreferences: {
            nodeIntegration: true
  }});
  

  //Load html into window
  mainWindow.loadURL(url.format({
    pathname: path.join(__dirname, "index.html"),
    protocol: "file:",
    slashes: true
  }));

  //Quit app when closed
  mainWindow.on("closed", function () {
    app.quit();
  })

  //Menu from template
  const mainMenu = Menu.buildFromTemplate(mainMenuTemplate);
  Menu.setApplicationMenu(mainMenu);

});

devices.on('device-activated', event => {
  console.log('Smart card reader active');
  const currentDevices = event.devices;

  let device = event.device;

  device.on('error', function (message) {
    console.log(`Error '${message}' received`);
  });
  device.on('card-inserted', event => {
    let card = event.card;
    //console.log(`Card '${card.getAtr()}' inserted into '${event.device}'` + '\n');
    const application = new Iso7816Application(card);

    application.selectFile([0xD6, 0x16, 0x00, 0x00, 0x30, 0x01, 0x01])
      .then(response => {
		  		  		console.info(`Response: '${response}' '${response.meaning()}'`);

        application.issueCommand([0x00, 0xA4, 0x02, 0x00, 0x02, 0x00, 0x02, 0x12])
          .then(response => {
			  		  		console.info(`Response: '${response}' '${response.meaning()}'`);

            application.issueCommand([0x00, 0xB0, 0x00, 0x00, 0xF8])
              .then(response => {
		  		console.info(`Response: '${response}' '${response.meaning()}'`);

                var response2 = `${response}`;

                var start = response2.indexOf("2a8468016504010101") + 18;
                response2 = response2.substring(start);

                while (1) {

                  var type = response2.substring(0, 2);

                  if (type == "30") break;

                  if (parseInt(response2.substring(2, 4), 16) > 127) {

                    var count = parseInt(response2.substring(2, 4), 16) - 128;
                    var length = "";
                    var k = 1;

                    for (k = 1; k <= count; k++) {

                      length += response2.substring(2 + (k * 2), 4 + (k * 2));

                    }

                    var total_length = parseInt(length, 16) * 2;
                    response2 = response2.substr(4 + (k - 1) * 2, total_length);

                  } else {

                    var total_length = parseInt(response2.substring(2, 4), 16) * 2 + 4;
                    response2 = response2.substr(4, total_length);

                  }
                }

                //region How to work with ASN.1 strings
                let bmp_string_encoded = new ArrayBuffer(response2.length / 2); 

                let bmp_string_view = new Uint8Array(bmp_string_encoded);

                var kk = 0;

                for (var i = 0; i < (response2.length / 2); i++) {

                  bmp_string_view[i] = "0x" + response2.substring(kk, kk + 2);
                  kk += 2;

                }

                let bmp_string_decoded = asn1js.fromBER(bmp_string_encoded);

                if (bmp_string_decoded.offset === (-1)) return; // Error during decoding

                let obj = bmp_string_decoded.result.valueBlock.value;

                var names = obj[4].valueBlock.value[0].valueBlock.value;
                var surnames = obj[3].valueBlock.value[0].valueBlock.value;
                var index = obj[5].valueBlock.value;

                var output = [names, surnames, index];
                
                printStudent(output);

              }).catch(error => {
                //console.error('Error:', error, error.stack + '\n');
              });
          }).catch(error => {
            //console.error('Error:', error, error.stack + '\n');
          });
      }).catch(error => {
        //console.error('Error:', error, error.stack + '\n');
      });

  });

  device.on('card-removed', event => {
    console.log(`Card removed from '${event.name}' ` + '\n');
  });

});

devices.on('device-deactivated', event => {
  console.log(`Device '${event.device}' deactivated, devices: [${event.devices}]` + '\n');
});

//Add student manually
function createAddWindow() {
  //Create new window
  AddWindow = new BrowserWindow({
    width: 300,
    height: 400,
    title: "Add student manually"
  });

  //Load html into window
  AddWindow.loadURL(url.format({
    pathname: path.join(__dirname, "addstudent.html"),
    protocol: "file:",
    slashes: true
  }));

  //Garbage
  AddWindow.on("close", function () {
    AddWindow = null;
  });
}

function createAddClassesWindow() {
  //Create new window
  AddClassesWindow = new BrowserWindow({
    width: 350,
    height: 500,
    title: "Add classes"
  });

  //Load html into window
  AddClassesWindow.loadURL(url.format({
    pathname: path.join(__dirname, "addclasses.html"),
    protocol: "file:",
    slashes: true
  }));

  //Garbage
  AddClassesWindow.on("close", function () {
    AddClassesWindow = null;
  });
}

function createSelectClassesWindow() {
  //Create new window
  SelectClassesWindow = new BrowserWindow({
    width: 500,
    height: 475,
    title: "Add classes"
  });

  //Load html into window
  SelectClassesWindow.loadURL(url.format({
    pathname: path.join(__dirname, "selectclasses.html"),
    protocol: "file:",
    slashes: true
  }));

  //Garbage
  SelectClassesWindow.on("close", function () {
    SelectClassesWindow = null;
  });

}


function printStudent(item) {

	var dateTime = require('node-datetime');
    var dt = dateTime.create();
    var formatted = dt.format('d-m-Y H:M:S');

	item.push(formatted);
    mainWindow.webContents.send("item:add", item);
 

	notifier.notify({
		title: "Student registered",
		message: item[0] + " " + item[1],
		icon: path.join(__dirname, 'ok.png')

	});
	  
/*
  if (false) { //current_classes == -1

    notifier.notify({

      title: "No current classes selected",
      message: "Adding student unsuccessful",
      icon: path.join(__dirname, 'wrong.png')

    });

  } else {

    if (true) {

      var dateTime = require('node-datetime');
      var dt = dateTime.create();
      var formatted = dt.format('d-m-Y H:M:S');

      item.push(formatted);
      console.log(item);

      mainWindow.webContents.send("item:add", item);
 

      notifier.notify({

        title: "Student registered",
        message: item[0] + " " + item[1],
        icon: path.join(__dirname, 'ok.png')

      });

    } else {

      notifier.notify({

        title: "Student already exists",
        message: item[0] + " " + item[1],
        icon: path.join(__dirname, 'wrong.png')

      });

    }

  }*/
}

//Catch
ipcMain.on("item:add", function (e, item) {

  printStudent(item);

  AddWindow.close();
})


//Menu template
const mainMenuTemplate = [{
  label: "Student",
  submenu: [{
      label: "Add student",
      accelerator: process.platfrom == "darwin" ? "Command+E" : "Ctrl+E",
      click() {
        createAddWindow();
      }
    },
    {
      label: "Quit program",
      accelerator: process.platfrom == "darwin" ? "Command+Q" : "Ctrl+Q",
      click() {
        app.quit();
      }
    }
  ]
}, {
  label: "Classes",
  submenu: [{
      label: "Add classes",
      click() {
        createAddClassesWindow();
      }
    },
    {
      label: "Pick classes",
      click() {
        createSelectClassesWindow();
      }
    }
  ]
}];

//If mac psuh empty obj to Menu
if (process.platfrom == "darwin") {
  mainMenuTemplate.unshift({});
}

//Add dev tools on DEV
if (process.env.NODE_ENV !== 'production') {
  mainMenuTemplate.push({
    label: "DEV",
    submenu: [{
        label: "Toggle dev tools",
        accelerator: process.platfrom == "darwin" ? "Command+I" : "Ctrl+I",
        click(item, focusedWindow) {
          focusedWindow.toggleDevTools();
        }
      },
      {
        role: "reload"
      }
    ]
  });
}