page.js

// This file contains functions which determine whether a given description of
// a YouTube page matches the YouTube page associated with a page filter.
// -----------------------------------------------------------------------------

/**
 * Reports whether the given YouTube page description matches a channel page.
 * 
 * @param {Element} _ - HTML element representing the YouTube page.
 * @param {string} path - Path and query components of the YouTube page URL.
 * @returns {boolean} - True iff the given element and path describe a channel page.
 */
function isChannelPage(element, _) {
    return element.querySelector("ytd-browse[page-subtype=channels]:not([hidden]) #channel-container") !== null;
}

/**
 * Reports whether the given YouTube page description matches the Home page.
 * 
 * @param {Element} _ - HTML element representing the YouTube page.
 * @param {string} path - Path and query components of the YouTube page URL.
 * @returns {boolean} - True iff the given element and path describe the Home page.
 */
function isHomePage(_, path) {
    return new RegExp("/$").test(path);
}

/**
 * Reports whether the given YouTube page description matches the Explore page.
 * 
 * @param {Element} _ - HTML element representing the YouTube page.
 * @param {string} path - Path and query components of the YouTube page URL.
 * @returns {boolean} - True iff the given element and path describe the Explore page.
 */
function isExplorePage(_, path) {
    return new RegExp("/feed/explore").test(path);
}

/**
 * Reports whether the given YouTube page description matches the Library page.
 * 
 * @param {Element} _ - HTML element representing the YouTube page.
 * @param {string} path - Path and query components of the YouTube page URL.
 * @returns {boolean} - True iff the given element and path describe the Library page.
 */
function isLibraryPage(_, path) {
    return new RegExp("/feed/library").test(path);
}

/**
 * Reports whether the given YouTube page description matches the History page.
 * 
 * @param {Element} _ - HTML element representing the YouTube page.
 * @param {string} path - Path and query components of the YouTube page URL.
 * @returns {boolean} - True iff the given element and path describe the History page.
 */
function isHistoryPage(_, path) {
    return new RegExp("/feed/history").test(path);
}

/**
 * Reports whether the given YouTube page description matches the Subscriptions page.
 * 
 * @param {Element} _ - HTML element representing the YouTube page.
 * @param {string} path - Path and query components of the YouTube page URL.
 * @returns {boolean} - True iff the given element and path describe the Subscriptions page.
 */
function isSubscriptionsPage(_, path) {
    return new RegExp("/feed/subscriptions").test(path);
}