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CSS rules utilities

function allowing to find or change the CSS rule(s) applied to an element

لا ينبغي أن لا يتم تثبيت هذا السكريت مباشرة. هو مكتبة لسكبتات لتشمل مع التوجيه الفوقية // @require https://update.greasyfork.org/scripts/394970/768785/CSS%20rules%20utilities.js 

// ==UserScript==
// @name         CSS rules utilities
// @namespace    http://tampermonkey.net/
// @version      0.4
// @description  functions allowing to get the CSS rules applied to an element
// @author       CoStiC
// @match        *://*/*
// @grant        none
// ==/UserScript==

function findCssRules(el) {
    var sheets = document.styleSheets, ret = [];
    el.matches = el.matches || el.webkitMatchesSelector || el.mozMatchesSelector || el.msMatchesSelector || el.oMatchesSelector;
    for (var i in sheets) {
        var rules = sheets[i].rules || sheets[i].cssRules;
        for (var r in rules) {
            if (el.matches(rules[r].selectorText)) {
                ret.push(rules[r].cssText);
            }
        }
    }
    return ret;
}

function modCssRules(el, newRule, frDoc) {
    if (!frDoc || (frDoc === window)) frDoc = window.document;
    let elHover = "",
        sheets = frDoc.styleSheets;

    if (el !== null) {
        el.matches = el.matches || el.webkitMatchesSelector || el.mozMatchesSelector || el.msMatchesSelector || el.oMatchesSelector;
        for (let sheet of sheets) {
            var rules = sheet.rules || sheet.cssRules;
            for (let rule of rules) {
                if (rule.type === 1) {
                    if (el.matches(rule.selectorText)) {

                        for (let newProp in newRule.cssNormal) {
                            rule.style[newProp] = newRule.cssNormal[newProp];
                        }

                        if (typeof newRule.cssHover !== 'undefined') {
                            var rul = "";
                            for (let propHover in newRule.cssHover) {
                                rul += `${propHover}:${newRule.cssHover[propHover]} !important;`;
                            };
                            elHover = `${rules[rule].selectorText}:hover{${rul}}`;
                        }
                    } else {};
                }
            }
        }
    }

    if (elHover !== "") {
        let newHoverStyle = document.createElement('style'),
            hoverRule = document.createTextNode(elHover);
        newHoverStyle.appendChild(hoverRule);
        document.head.appendChild(newHoverStyle)
        //sheets[sheets.length - 1].insertRule(elHover);
    };
}