nystudio107 / craft-twigfield

/**

 * Create a Monaco Editor instance

 *

 * @param {string} elementId - The id of the TextArea or Input element to replace with a Monaco editor

 * @param {string} fieldType - The field's passed in type, used for autocomplete caching

 * @param {string} wrapperClass - Classes that should be added to the field's wrapper <div>

 * @param {IStandaloneEditorConstructionOptions} editorOptions - Monaco editor options

 * @param {string} codefieldOptions - JSON encoded string of arbitrary CodefieldOptions for the field

 * @param {string} endpointUrl - The controller action endpoint for generating autocomplete items

 * @param {string} placeholderText - Placeholder text to use for the field

 */

function makeMonacoEditor(elementId: string, fieldType: string, wrapperClass: string, editorOptions: string, codefieldOptions: string, endpointUrl: string, placeholderText = ''): monaco.editor.IStandaloneCodeEditor | undefined {

  const textArea = <HTMLInputElement>document.getElementById(elementId);

  const container = document.createElement('div');

  const fieldOptions: CodefieldOptions = JSON.parse(codefieldOptions);

  const placeholderId = elementId + '-monaco-editor-placeholder';

  // If we can't find the passed in text area or if there is no parent node, return

  if (textArea === null || textArea.parentNode === null) {

    return;

  }

  // Monaco editor defaults, coalesced together

  const monacoEditorOptions: monaco.editor.IStandaloneEditorConstructionOptions = JSON.parse(editorOptions);

  const options: monaco.editor.IStandaloneEditorConstructionOptions = {...defaultMonacoEditorOptions, ...monacoEditorOptions, ...{value: textArea.value}}

  // Make a sibling div for the Monaco editor to live in

  container.id = elementId + '-monaco-editor';

  container.classList.add('relative', 'box-content', 'monaco-editor-codefield', 'h-full');

  // Add the icon in, if there is one

  const iconHtml = typeof options.language === "undefined" ? null : languageIcons[options.language];

  if (iconHtml) {

    const icon = document.createElement('div');

    icon.classList.add('monaco-editor-codefield--icon');

    icon.setAttribute('title', Craft.t('twigfield', 'Twig code is supported.'));

    icon.setAttribute('aria-hidden', 'true');

    icon.innerHTML = iconHtml;

    container.appendChild(icon);

  }

  // Apply any passed in classes to the wrapper div

  if (wrapperClass !== '') {

    const cl = container.classList;

    const classArray = wrapperClass.trim().split(/\s+/);

    cl.add(...classArray);

  }

  // Handle the placeholder text (if any)

  if (placeholderText !== '') {

    const placeholder = document.createElement('div');

    placeholder.id = elementId + '-monaco-editor-placeholder';

    placeholder.innerHTML = placeholderText;

    placeholder.classList.add('monaco-placeholder', 'p-2');

    container.appendChild(placeholder);

  }

  textArea.parentNode.insertBefore(container, textArea);

  textArea.style.display = 'none';

  // Create the Monaco editor

  const editor = monaco.editor.create(container, options);

  // When the text is changed in the editor, sync it to the underlying TextArea input

  editor.onDidChangeModelContent(() => {

    textArea.value = editor.getValue();

  });

  // ref: https://github.com/vikyd/vue-monaco-singleline/blob/master/src/monaco-singleline.vue#L150

  if ('singleLineEditor' in fieldOptions && fieldOptions.singleLineEditor) {

    const textModel: monaco.editor.ITextModel | null = editor.getModel();

    if (textModel !== null) {

      // Remove multiple spaces & tabs

      const text = textModel.getValue();

      textModel.setValue(text.replace(/\s\s+/g, ' '));

      // Handle the Find command

      editor.addCommand(monaco.KeyMod.CtrlCmd | monaco.KeyCode.KeyF, () => {

      });

      // Handle typing the Enter key

      editor.addCommand(monaco.KeyCode.Enter, () => {

      }, '!suggestWidgetVisible');

      // Handle typing the Tab key

      editor.addCommand(monaco.KeyCode.Tab, () => {

        focusNextElement();

      });

      editor.addCommand(monaco.KeyMod.Shift | monaco.KeyCode.Tab, () => {

        focusPrevElement();

      });

      // Handle Paste

      editor.onDidPaste(() => {

        // multiple rows will be merged to single row

        let newContent = '';

        const lineCount = textModel.getLineCount();

        // remove all line breaks

        for (let i = 0; i < lineCount; i += 1) {

          newContent += textModel.getLineContent(i + 1);

        }

        // Remove multiple spaces & tabs

        newContent = newContent.replace(/\s\s+/g, ' ');

        textModel.setValue(newContent);

        editor.setPosition({column: newContent.length + 1, lineNumber: 1});

      })

    }

  }

  // Get the autocompletion items

  getCompletionItemsFromEndpoint(fieldType, codefieldOptions, endpointUrl);

  // Custom resizer to always keep the editor full-height, without needing to scroll

  let ignoreEvent = false;

  const updateHeight = () => {

    const width = editor.getLayoutInfo().width;

    const contentHeight = Math.min(1000, editor.getContentHeight());

    //container.style.width = `${width}px`;

    container.style.height = `${contentHeight}px`;

    try {

      ignoreEvent = true;

      editor.layout({width, height: contentHeight});

    } finally {

      ignoreEvent = false;

    }

  };

  editor.onDidContentSizeChange(updateHeight);

  updateHeight();

  // Handle the placeholder

  if (placeholderText !== '') {

    showPlaceholder('#' + placeholderId, editor.getValue());

    editor.onDidBlurEditorWidget(() => {

      showPlaceholder('#' + placeholderId, editor.getValue());

    });

    editor.onDidFocusEditorWidget(() => {

      hidePlaceholder('#' + placeholderId);

    });

  }

  /**

   * Move the focus to the next element

   */

  function focusNextElement(): void {

    const focusable = getFocusableElements();

    if (document.activeElement instanceof HTMLFormElement) {

      const index = focusable.indexOf(document.activeElement);

      if (index > -1) {

        const nextElement = focusable[index + 1] || focusable[0];

        nextElement.focus();

      }

    }

  }

  /**

   * Move the focus to the previous element

   */

  function focusPrevElement(): void {

    const focusable = getFocusableElements();

    if (document.activeElement instanceof HTMLFormElement) {

      const index = focusable.indexOf(document.activeElement);

      if (index > -1) {

        const prevElement = focusable[index - 1] || focusable[focusable.length];

        prevElement.focus();

      }

    }

  }

  /**

   * Get the focusable elements in the current form

   *

   * @returns {Array<HTMLElement>} - An array of HTMLElements that can be focusable

   */

  function getFocusableElements(): Array<HTMLElement> {

    let focusable: Array<HTMLElement> = [];

    // add all elements we want to include in our selection

    const focusableElements = 'a:not([disabled]), button:not([disabled]), select:not([disabled]), input[type=text]:not([disabled]), [tabindex]:not([disabled]):not([tabindex="-1"])';

    if (document.activeElement instanceof HTMLFormElement) {

      const activeElement: HTMLFormElement = document.activeElement;

      if (activeElement && activeElement.form) {

        focusable = Array.prototype.filter.call(activeElement.form.querySelectorAll(focusableElements),

          function (element) {

            if (element instanceof HTMLElement) {

              //check for visibility while always include the current activeElement

              return element.offsetWidth > 0 || element.offsetHeight > 0 || element === document.activeElement

            }

            return false;

          });

      }

    }

    return focusable;

  }

  /**

   * Show the placeholder text

   *

   * @param {string} selector - The selector for the placeholder element

   * @param {string} value - The editor field's value (the text)

   */

  function showPlaceholder(selector: string, value: string): void {

    if (value === "") {

      const elem = <HTMLElement>document.querySelector(selector);

      if (elem !== null) {

        elem.style.display = "initial";

      }

    }

  }

  /**

   * Hide the placeholder text

   *

   * @param {string} selector - The selector for the placeholder element

   */

  function hidePlaceholder(selector: string): void {

    const elem = <HTMLElement>document.querySelector(selector);

    if (elem !== null) {

      elem.style.display = "none";

    }

  }

  return editor;