PCv5/app/static/scripts/editor.js

/* Add callbacks on text formatting buttons */

function editor_bold(e) {
    let ta = document.querySelector(".editor textarea");
    let indexStart = ta.selectionStart;
    let indexEnd = ta.selectionEnd;
    let txt = ta.value.substring(indexStart, indexEnd);
    ta.value += '\n' + 'bold';
}


// Tab insert some spaces
// Ctrl+Enter send the form
ta = document.querySelector(".editor textarea");
ta.addEventListener('keydown', function(e) {
    let keyCode = e.keyCode || e.which;
    if (keyCode == 9) {
		// TODO Add one tab to selected text without replacing it
        e.preventDefault();

        let start = e.target.selectionStart;
        let end = e.target.selectionEnd;
        // set textarea value to: text before caret + tab + text after caret
        e.target.value = e.target.value.substring(0, start) + "\t" + e.target.value.substring(end);
        e.target.selectionEnd = start + 1;
    }
    if (e.ctrlKey && keyCode == 13) {
        let t = e.target;
        while(! (t instanceof HTMLFormElement)) {
            t = t.parentNode;
        }
        try {
            t.submit();
        } catch(exception) {
            t.submit.click();
        }
    }
});