/*******************************************************************************

    uBlock Origin - a comprehensive, efficient content blocker
    Copyright (C) 2025-present Raymond Hill

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see {http://www.gnu.org/licenses/}.

    Home: https://github.com/gorhill/uBlock

*/

import { registerScriptlet } from './base.js';
import { safeSelf } from './safe-self.js';

/**
 * @scriptlet prevent-innerHTML
 * 
 * @description
 * Conditionally prevent assignment to `innerHTML` property.
 * 
 * @param [selector]
 * Optional. The element must matches `selector` for the prevention to take
 * place.
 * 
 * @param [pattern]
 * Optional. A pattern to match against the assigned value. The pattern can be
 * a plain string, or a regex. Prepend with `!` to reverse the match condition.
 * 
 * */

export function preventInnerHTML(
    selector = '',
    pattern = ''
) {
    const safe = safeSelf();
    const logPrefix = safe.makeLogPrefix('prevent-innerHTML', selector, pattern);
    const matcher = safe.initPattern(pattern, { canNegate: true });
    const current = safe.Object_getOwnPropertyDescriptor(Element.prototype, 'innerHTML');
    if ( current === undefined ) { return; }
    const shouldPreventSet = (elem, a) => {
        if ( selector !== '' ) {
            if ( typeof elem.matches !== 'function' ) { return false; }
            if ( elem.matches(selector) === false ) { return false; }
        }
        return safe.testPattern(matcher, a);
    };
    Object.defineProperty(Element.prototype, 'innerHTML', {
        get: function() {
            return current.get
                ? current.get.call(this)
                : current.value;
        },
        set: function(a) {
            if ( shouldPreventSet(this, a) ) {
                safe.uboLog(logPrefix, 'Prevented');
            } else if ( current.set ) {
                current.set.call(this, a);
            }
            if ( safe.logLevel > 1 ) {
                safe.uboLog(logPrefix, `Assigned:\n${a}`);
            }
            current.value = a;
        },
    });
}
registerScriptlet(preventInnerHTML, {
    name: 'prevent-innerHTML.js',
    dependencies: [
        safeSelf,
    ],
});
