Merge branch 'jb50498' into 'master'

[embedlite-components] Introduce ClickEventBlocker.js. JB#50498

See merge request mer-core/embedlite-components!73

jsscripts/ClickEventBlocker.js

+/*
+ * Copyright (c) 2020 Open Mobile Platform LLC.
+ */
+
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+Components.utils.import("resource://gre/modules/Services.jsm");
+
+var ClickEventBlocker = {
+    _context: null,
+
+    init: function init(context) {
+        this._context = context
+        Services.els.addSystemEventListener(context, "click", this, true);
+    },
+
+    handleEvent(event) {
+        switch (event.type) {
+        case "click":
+            event.preventDefault()
+            let originalTarget = event.originalTarget;
+            let ownerDoc = originalTarget.ownerDocument;
+            if (!ownerDoc) {
+                return;
+            }
+
+            let href = this._hrefAndLinkNodeForClickEvent(event);
+            if (href) {
+                sendAsyncMessage("embed:OpenLink", {
+                                     "uri":  href
+                                 })
+            }
+        }
+    },
+
+
+  /**
+   * Extracts linkNode and href for the current click target.
+   *
+   * @param event
+   *        The click event.
+   * @return [href, linkNode, linkPrincipal].
+   *
+   * @note linkNode will be null if the click wasn't on an anchor
+   *       element. This includes SVG links, because callers expect |node|
+   *       to behave like an <a> element, which SVG links (XLink) don't.
+   */
+  _hrefAndLinkNodeForClickEvent(event) {
+    function isHTMLLink(aNode) {
+      // Be consistent with what nsContextMenu.js does.
+      return ((aNode instanceof content.HTMLAnchorElement && aNode.href) ||
+              (aNode instanceof content.HTMLAreaElement && aNode.href) ||
+              aNode instanceof content.HTMLLinkElement);
+    }
+
+    let node = event.target;
+    while (node && !isHTMLLink(node)) {
+      node = node.parentNode;
+    }
+
+    if (node)
+      return node.href;
+
+    // If there is no linkNode, try simple XLink.
+    let href, baseURI;
+    node = event.target;
+    while (node && !href) {
+      if (node.nodeType == content.Node.ELEMENT_NODE &&
+          (node.localName == "a" ||
+           node.namespaceURI == "http://www.w3.org/1998/Math/MathML")) {
+        href = node.getAttribute("href") ||
+               node.getAttributeNS("http://www.w3.org/1999/xlink", "href");
+        if (href) {
+          baseURI = node.ownerDocument.baseURIObject;
+          break;
+        }
+      }
+      node = node.parentNode;
+    }
+
+    // In case of XLink, we don't return the node we got href from since
+    // callers expect <a>-like elements.
+    // Note: makeURI() will throw if aUri is not a valid URI.
+    return href ? Services.io.newURI(href, null, baseURI).spec : null;
+  }
+};

jsscripts/Makefile.am

@@ -8,6 +8,7 @@ jsscripts_manifest_DATA = \
 	SelectionHandler.js \
 	SelectionPrototype.js \
 	Util.js \
+        ClickEventBlocker.js \
 	ContextMenuHandler.js \
 	Prompt.jsm \
 	$(NULL)

link_to_system.sh

@@ -66,6 +66,7 @@ ln -s $(pwd)/jsscripts/SelectionHandler.js $TARGET_DIR/chrome/embedlite/content/
 ln -s $(pwd)/jsscripts/SelectionPrototype.js $TARGET_DIR/chrome/embedlite/content/SelectionPrototype.js;
 ln -s $(pwd)/jsscripts/Util.js $TARGET_DIR/chrome/embedlite/content/Util.js;
 ln -s $(pwd)/jsscripts/Logger.js $TARGET_DIR/chrome/embedlite/content/Logger.js;
+ln -s $(pwd)/jsscripts/ClickEventBlocker.js $TARGET_DIR/chrome/embedlite/content/ClickEventBlocker.js;
 ln -s $(pwd)/jsscripts/ContextMenuHandler.js $TARGET_DIR/chrome/embedlite/content/ContextMenuHandler.js;
 ln -s $(pwd)/search-engines/google.xml $TARGET_DIR/chrome/embedlite/content/google.xml;
 ln -s $(pwd)/search-engines/bing.xml $TARGET_DIR/chrome/embedlite/content/bing.xml;