From dc187a9a3a97d5f1e4fdda58810828757031a12a Mon Sep 17 00:00:00 2001
From: DebaucheryLibrarian <moonloop.adult@protonmail.com>
Date: Sun, 19 Dec 2021 23:03:44 +0100
Subject: [PATCH] Added execute method to qu, removed runScripts from Gamma's
 fetchMovie to observe effect on memory usage.

---
 src/scrapers/gamma.js | 10 ++---
 src/utils/qu.js       | 93 +++++++++++++++++++++++++++++++++++++------
 2 files changed, 85 insertions(+), 18 deletions(-)

diff --git a/src/scrapers/gamma.js b/src/scrapers/gamma.js
index da338d6d..9ddc1abb 100644
--- a/src/scrapers/gamma.js
+++ b/src/scrapers/gamma.js
@@ -463,7 +463,9 @@ async function fetchMovieTrailer(release) {
 
 async function scrapeMovie({ query, el }, window, url, entity, options) {
 	const release = {};
-	const rawData = window.dataLayer[0]?.dvdDetails;
+
+	const { dataLayer } = query.exec('//script[contains(text(), "dataLayer")]', ['dataLayer']);
+	const rawData = dataLayer?.[0]?.dvdDetails;
 	const data = rawData.dvdId && rawData; // dvdDetails is mostly empty in some cache states
 
 	release.entryId = new URL(url).pathname.match(/\/(\d+)(\/|$)/)?.[1];
@@ -750,11 +752,7 @@ async function fetchScene(url, site, baseRelease, options) {
 }
 
 async function fetchMovie(url, channel, baseRelease, options) {
-	const res = await qu.get(url, null, null, {
-		extract: {
-			runScripts: 'dangerously',
-		},
-	});
+	const res = await qu.get(url, null, null);
 
 	if (res.ok) {
 		return scrapeMovie(res.item, res.window, url, channel, options);
diff --git a/src/utils/qu.js b/src/utils/qu.js
index 0c7b54fe..1989c650 100644
--- a/src/utils/qu.js
+++ b/src/utils/qu.js
@@ -84,32 +84,69 @@ function prefixUrl(urlValue, origin, protocol = 'https') {
 	return urlValue;
 }
 
+function iterateXPathResult(iterator, results = []) {
+	const element = iterator.iterateNext();
+
+	if (element) {
+		return iterateXPathResult(iterator, [...results, element]);
+	}
+
+	return results;
+}
+
+function getElements(context, selector, first = false) {
+	if (!selector) {
+		return context;
+	}
+
+	if (/^\/\//.test(selector)) {
+		// XPath selector
+		const iterator = globalWindow.document.evaluate(selector, context, null, globalWindow.XPathResult.ORDERED_NODE_ITERATOR_TYPE, null);
+
+		if (first) {
+			return iterator.iterateNext();
+		}
+
+		return iterateXPathResult(iterator);
+	}
+
+	if (first) {
+		return context.querySelector(selector);
+	}
+
+	return Array.from(context.querySelectorAll(selector));
+}
+
 function q(context, selector, attrArg, applyTrim = true) {
 	if (!selector && context.nodeName === '#document') {
 		return null;
 	}
 
 	const attr = attrArg === true ? 'textContent' : attrArg;
+	const element = getElements(context, selector, true);
+
+	if (!element) {
+		return null;
+	}
 
 	if (attr) {
-		const value = selector
-			? context.querySelector(selector)?.[attr] || context.querySelector(selector)?.attributes[attr]?.value
-			: context[attr] || context.getAttribute(attr);
+		const value = element[attr] || element.getAttribute(attr);
 
 		return applyTrim && typeof value === 'string' ? trim(value) : value;
 	}
 
-	return selector ? context.querySelector(selector) : context;
+	return element;
 }
 
 function all(context, selector, attrArg, applyTrim = true) {
 	const attr = attrArg === true ? 'textContent' : attrArg;
+	const elements = getElements(context, selector);
 
 	if (attr) {
-		return Array.from(context.querySelectorAll(selector), (el) => q(el, null, attr, applyTrim));
+		return elements.map((el) => q(el, null, attr, applyTrim));
 	}
 
-	return Array.from(context.querySelectorAll(selector));
+	return elements;
 }
 
 function exists(context, selector) {
@@ -134,6 +171,42 @@ function html(context, selector) {
 	return el && el.innerHTML;
 }
 
+function htmls(context, selector) {
+	const els = all(context, selector, null, true);
+
+	return els.map((el) => el.innerHTML);
+}
+
+function execute(context, selector = 'script') {
+	const scripts = htmls(context, selector);
+	const originalGlobal = Object.fromEntries(Object.entries(global));
+
+	const errors = scripts?.reduce((accErrors, script) => {
+		try {
+			Function(script)(); /* eslint-disable-line no-new-func */
+
+			return accErrors;
+		} catch (error) {
+			// the script failed
+			return [...accErrors, error];
+		}
+	}, []);
+
+	const data = Object.fromEntries(Object.entries(global).filter(([key, value]) => {
+		if (originalGlobal[key] !== value) {
+			delete global[key];
+			return true;
+		}
+
+		return false;
+	}));
+
+	return {
+		...data,
+		errors,
+	};
+}
+
 function json(context, selector) {
 	const el = q(context, selector, null, true);
 
@@ -156,12 +229,6 @@ function jsons(context, selector) {
 	});
 }
 
-function htmls(context, selector) {
-	const els = all(context, selector, null, true);
-
-	return els.map((el) => el.innerHTML);
-}
-
 function texts(context, selector, applyTrim = true, filter = true) {
 	const el = q(context, selector, null, applyTrim);
 	if (!el) return null;
@@ -429,6 +496,8 @@ const quFuncs = {
 	duration,
 	el: q,
 	element: q,
+	execute,
+	exec: execute,
 	exists,
 	html,
 	htmls,