renderer.js

const electron = require("electron");
const remote = electron.remote;
const ipcRenderer = electron.ipcRenderer;
const fs = require("fs"); //filesystem
const katex = require("katex");
const {Menu, MenuItem} = remote

var notePath = "";

const contextMenu = new Menu();
contextMenu.append(new MenuItem({label: "Undo", role: "undo" }));
contextMenu.append(new MenuItem({label: "Redo", role: "redo" }));
contextMenu.append(new MenuItem({type: "separator"}))
contextMenu.append(new MenuItem({label: "Cut", role: "cut" }));
contextMenu.append(new MenuItem({label: "Copy", role: "copy" }));
contextMenu.append(new MenuItem({label: "Paste", role: "paste" }));
contextMenu.append(new MenuItem({type: "separator"}))
contextMenu.append(new MenuItem({label: "Select all", role: "selectall" }));
//contextMenu.append(new MenuItem({type: "separator"}))
//contextMenu.append(new MenuItem({label: "Insert formula", click() { addFormula(); } })); // TODO: add KATEX and/or MathQuill support!

var optionsMenu = new Menu();
optionsMenu.append(new MenuItem({label: "Pin note", click() { pinNote(); }, id: "isNotePinned", checked: false }));
optionsMenu.append(new MenuItem({label: "Close note", click() { closeNote(); }}));
optionsMenu.append(new MenuItem({label: "Close all", click() { closeAll(); }}));
optionsMenu.append(new MenuItem({label: "Delete note", click() { deleteNote() }}));

var quill = new Quill("#editor", {
    modules: {
        syntax: false,
        formula: true,
        toolbar: "#titlebar"
    },
    formats: {
        bold: true,
        size: false,
        link: false,
        formula: true
    },
    theme: "snow"
});

ipcRenderer.on("loadFile", (event, arg) => {
    notePath = arg;

    console.log(notePath);

    fs.readFile(notePath, "utf8", function(err, data){
        if (err) {
            if (document.getElementById("editor").textContent == null) {
                quill.setText("Hello, world!");
            }
            return console.error(err);
        } else {
            let buff = document.getElementById("editor").textContent;
            quill.setText(data.trim());
            if (buff != null) {
                quill.insertText(buff);
            }
        }
    })
});

quill.on("text-change", function(delta, oldDelta, source) {
    if (source == "api") {
        console.log("An API call triggered this change.");
    } else if (source == "user") {
        fs.writeFile(notePath, quill.getText(), function(err, data){ //should this be synchronous instead?
            if (err) {
                return console.error(err);
            }
        });
    }
});

function addFormula() {
    quill.tooltip.show();
    //quill.tooltip.edit("formula");
}

function pinNote() {
    const window = remote.getCurrentWindow();
    let isNotePinned = !window.isAlwaysOnTop();
    window.setAlwaysOnTop(isNotePinned);
    //optionsMenu.getMenuItemById("isNotePinned").checked = isNotePinned; // TODO: Doesn't update automatically, fix
}

function closeNote() {
    const window = remote.getCurrentWindow();
    window.close();
}

function closeAll() {
    ipcRenderer.sendSync("closeAll");
}

function newNote() {
    ipcRenderer.send("newNote");
}

function deleteNote() {
    // TODO: add prompt to confirm deletion!
    try {
        fs.unlinkSync(notePath); // delete the note
    } catch (err) {
        console.error(err.message); // log error
    }

    closeNote();
}

function init() {
    document.getElementById("buttonOptions").addEventListener("click", function(e) {
        e.preventDefault()
        optionsMenu.popup({window: remote.getCurrentWindow()})
    }, false);

    document.getElementById("buttonNewNote").addEventListener("click", function(e) {
        newNote();
    });

    window.addEventListener("contextmenu", (e) => {
        e.preventDefault()
        contextMenu.popup({window: remote.getCurrentWindow()})
    }, false)
}

document.onreadystatechange = function () {
    if (document.readyState == "complete") {
        init();
    }
}