add initial marp implementation with sample content and build configuration

node_modules/mathjax-full/ts/ui/menu/SelectableInfo.ts

@@ -0,0 +1,82 @@
+/*************************************************************
+ *
+ *  Copyright (c) 2019-2022 The MathJax Consortium
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+/**
+ * @fileoverview  An info box that allows text selection and has copy-to-clipboard functions
+ *
+ * @author dpvc@mathjax.org (Davide Cervone)
+ */
+
+import {Info} from 'mj-context-menu/js/info.js';
+import {HtmlClasses} from 'mj-context-menu/js/html_classes.js';
+
+/*==========================================================================*/
+
+/**
+ * The SelectableInfo class definition
+ */
+export class SelectableInfo extends Info {
+
+  /**
+   * Add a keypress event to handle "select all" so that only
+   * the info-box's text is selected (not the whole page)
+   *
+   * @override
+   */
+  public addEvents(element: HTMLElement) {
+    element.addEventListener('keypress', (event: KeyboardEvent) => {
+      if (event.key === 'a' && (event.ctrlKey || event.metaKey)) {
+        this.selectAll();
+        this.stop(event);
+      }
+    });
+  }
+
+  /**
+   * Select all the main text of the info box
+   */
+  public selectAll() {
+    const selection = document.getSelection();
+    selection.selectAllChildren(this.html.querySelector('pre'));
+  }
+
+  /**
+   * Implement the copy-to-clipboard action
+   */
+  public copyToClipboard() {
+    this.selectAll();
+    try {
+      document.execCommand('copy');
+    } catch (err) {
+      alert('Can\'t copy to clipboard: ' + err.message);
+    }
+    document.getSelection().removeAllRanges();
+  }
+
+  /**
+   * Attach the copy-to-clipboard action to its button
+   */
+  public generateHtml() {
+    super.generateHtml();
+    const footer = this.html.querySelector('span.' + HtmlClasses['INFOSIGNATURE']);
+    const button = footer.appendChild(document.createElement('input'));
+    button.type = 'button';
+    button.value = 'Copy to Clipboard';
+    button.addEventListener('click', (_event: MouseEvent) => this.copyToClipboard());
+  }
+
+}