uBlock/platform/mv3/extension/js/scripting/css-declarative.js

116 lines
3.5 KiB
JavaScript

/*******************************************************************************
uBlock Origin - a browser extension to block requests.
Copyright (C) 2014-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
*/
/* jshint esversion:11 */
'use strict';
/******************************************************************************/
// Important!
// Isolate from global scope
(function uBOL_cssDeclarative() {
/******************************************************************************/
const declarativeImports = self.declarativeImports || [];
const lookupSelectors = (hn, out) => {
for ( const { argsList, hostnamesMap } of declarativeImports ) {
let argsIndices = hostnamesMap.get(hn);
if ( argsIndices === undefined ) { continue; }
if ( typeof argsIndices === 'number' ) { argsIndices = [ argsIndices ]; }
for ( const argsIndex of argsIndices ) {
const details = argsList[argsIndex];
if ( details.n && details.n.includes(hn) ) { continue; }
out.push(...details.a.map(json => JSON.parse(json)));
}
}
};
let hn;
try { hn = document.location.hostname; } catch(ex) { }
const selectors = [];
while ( hn ) {
lookupSelectors(hn, selectors);
if ( hn === '*' ) { break; }
const pos = hn.indexOf('.');
if ( pos !== -1 ) {
hn = hn.slice(pos + 1);
} else {
hn = '*';
}
}
declarativeImports.length = 0;
/******************************************************************************/
if ( selectors.length === 0 ) { return; }
const cssRuleFromProcedural = details => {
const { tasks, action } = details;
let mq;
if ( tasks !== undefined ) {
if ( tasks.length > 1 ) { return; }
if ( tasks[0][0] !== 'matches-media' ) { return; }
mq = tasks[0][1];
}
let style;
if ( Array.isArray(action) ) {
if ( action[0] !== 'style' ) { return; }
style = action[1];
}
if ( mq === undefined && style === undefined ) { return; }
if ( mq === undefined ) {
return `${details.selector}\n{${style}}`;
}
if ( style === undefined ) {
return `@media ${mq} {\n${details.selector}\n{display:none!important;}\n}`;
}
return `@media ${mq} {\n${details.selector}\n{${style}}\n}`;
};
const sheetText = [];
for ( const selector of selectors ) {
const ruleText = cssRuleFromProcedural(selector);
if ( ruleText === undefined ) { continue; }
sheetText.push(ruleText);
}
if ( sheetText.length === 0 ) { return; }
try {
const sheet = new CSSStyleSheet();
sheet.replace(`@layer{${sheetText.join('\n')}}`);
document.adoptedStyleSheets = [
...document.adoptedStyleSheets,
sheet
];
} catch(ex) {
}
/******************************************************************************/
})();
/******************************************************************************/