latex_transport.js

// latex_transport.js -- BACKGROUND SCRIPT THAT SERVES AS A GO-BETWEEN FOR dblclick_edit.js and popup.js

let Browser;
// DETECT BROWSER TYPE FOR PROPER API USE
try {
    // FOR FIREFOX
    Browser = browser;
} catch(e) {
    try {
        // FOR CHROME
        Browser = chrome;
    } catch(e) {
        console.error('TeX Math Here: latex_transport.js: ERROR! BROWSER TYPE NOT DETECTED.');
    }
}

Browser.runtime.onMessage.addListener(function(message, sender, sendBack) {
    // DETERMINE WHAT ACTION TO TAKE
    switch (message.type)
    {
        case 'latex_store':
        localStorage.setItem('latex', message.latex);
        break;
        case 'latex_retrieve':
        let latex_data;

        // IF NOTHING IS STORED
        if (localStorage.getItem('latex') == null)
        {
            latex_data = 'undefined';
        }
        else    // SOMETHING IS STORED
        {
            latex_data = localStorage.getItem('latex');
            localStorage.removeItem('latex');
        }

        sendBack(latex_data);
        break;
        default:
        console.error('TeX Math Here: latex_transport.js: ERROR! UNKNOWN MESSAGE RECEIVED.');
    }
});