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Colored background for Google Calendar timed events in month view
// ==UserScript==
// @name Colorize GCal:monthly timed events
// @description Colored background for Google Calendar timed events in month view
// @include https://calendar.google.com/*
// @version 1.1
// @author wOxxOm
// @namespace wOxxOm.scripts
// @license MIT License
// @run-at document-start
// @require https://greasyfork.org/scripts/12228/code/setMutationHandler.js
// @require https://cdnjs.cloudflare.com/ajax/libs/tinycolor/1.4.1/tinycolor.min.js
// ==/UserScript==
setMutationHandler(document,
'span.goog-inline-block[style*="background-color:"],' +
'.st-c-pos .rb-n[style*="background-color:"],' +
'.st-c-pos .te[style*="color:"]',
function(nodes) {
nodes.forEach(function(n) {
var bg = n.style.backgroundColor;
var fg = n.style.color;
n.style.color = n.style.backgroundColor = '';
var appointment = n.className.indexOf('goog-inline-block')>=0 ? n.parentNode : n;
var color = appointment.style.backgroundColor = bg || fg;
var isDark = tinycolor(color).getBrightness() < 150; // brightness range is 0-255
appointment.style.color = isDark ? 'white' : 'black';
if (isDark && n.classList.contains('rb-n')) {
n.style.fontWeight = 'bold';
var v = n.querySelector('.rem-ic'); if (v) v.style.filter = 'invert(1)';
v = n.querySelector('.rb-ni'); if (v) v.style.color = 'white';
}
if (n.style.border)
n.style.border = '';
});
return true;
});