✨ Import text-editor code into the repository

frontend/text-editor/editor/content/dom/TextNode.js

@@ -0,0 +1,64 @@
+/**
+ * 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/.
+ *
+ * Copyright (c) KALEIDOS INC
+ */
+
+import { isInline } from "./Inline";
+import { isLineBreak } from "./LineBreak";
+import { isParagraph } from "./Paragraph";
+import { isRoot } from "./Root";
+
+/**
+ * Returns true if the node is "like"
+ * text, this means that it is a Text
+ * node or a <br> element.
+ *
+ * @param {Node} node
+ * @returns {boolean}
+ */
+export function isTextNode(node) {
+  if (!node) throw new TypeError("Invalid text node");
+  return node.nodeType === Node.TEXT_NODE
+      || isLineBreak(node);
+}
+
+/**
+ * Returns true if the text node is empty.
+ *
+ * @param {Node} node
+ * @returns {boolean}
+ */
+export function isEmptyTextNode(node) {
+  return node.nodeType === Node.TEXT_NODE
+      && node.nodeValue === "";
+}
+
+/**
+ * Returns the content length of the
+ * node.
+ *
+ * @param {Node} node
+ * @returns {number}
+ */
+export function getTextNodeLength(node) {
+  if (!node) throw new TypeError("Invalid text node");
+  if (isLineBreak(node)) return 0;
+  return node.nodeValue.length;
+}
+
+/**
+ * Gets the closest text node.
+ *
+ * @param {Node} node
+ * @returns {Node}
+ */
+export function getClosestTextNode(node) {
+  if (isTextNode(node)) return node;
+  if (isInline(node)) return node.firstChild;
+  if (isParagraph(node)) return node.firstChild.firstChild;
+  if (isRoot(node)) return node.firstChild.firstChild.firstChild;
+  throw new Error("Cannot find a text node");
+}