Use github markdown utils in core, support key handlers (#2826)

This simplifies the markdown extension and allows BBCode to use these features.
It also allows undoing stuff like inserting replies/mentions

framework/core/js/src/common/compat.js

@@ -8,6 +8,8 @@ import ItemList from './utils/ItemList';
 import mixin from './utils/mixin';
 import humanTime from './utils/humanTime';
 import computed from './utils/computed';
+import insertText from './utils/insertText';
+import styleSelectedText from './utils/styleSelectedText';
 import Drawer from './utils/Drawer';
 import anchorScroll from './utils/anchorScroll';
 import RequestError from './utils/RequestError';
@@ -88,6 +90,8 @@ export default {
   'utils/mixin': mixin,
   'utils/humanTime': humanTime,
   'utils/computed': computed,
+  'utils/insertText': insertText,
+  'utils/styleSelectedText': styleSelectedText,
   'utils/Drawer': Drawer,
   'utils/anchorScroll': anchorScroll,
   'utils/RequestError': RequestError,

framework/core/js/src/common/utils/BasicEditorDriver.ts

@@ -1,5 +1,7 @@
 import getCaretCoordinates from 'textarea-caret';
+import insertText from './insertText';
 import EditorDriverInterface, { EditorDriverParams } from './EditorDriverInterface';
+import ItemList from './ItemList';
 
 export default class BasicEditorDriver implements EditorDriverInterface {
   el: HTMLTextAreaElement;
@@ -32,19 +34,25 @@ export default class BasicEditorDriver implements EditorDriverInterface {
     this.el.onclick = callInputListeners;
     this.el.onkeyup = callInputListeners;
 
-    this.el.addEventListener('keydown', function (e) {
-      if ((e.metaKey || e.ctrlKey) && e.key === 'Enter') {
-        params.onsubmit();
-      }
+    this.el.addEventListener('keydown', (e) => {
+      this.keyHandlers(params)
+        .toArray()
+        .forEach((handler) => handler(e));
     });
 
     dom.append(this.el);
   }
 
-  protected setValue(value: string) {
-    $(this.el).val(value).trigger('input');
+  keyHandlers(params: EditorDriverParams): ItemList {
+    const items = new ItemList();
 
-    this.el.dispatchEvent(new CustomEvent('input', { bubbles: true, cancelable: true }));
+    items.add('submit', function (e) {
+      if ((e.metaKey || e.ctrlKey) && e.key === 'Enter') {
+        params.onsubmit();
+      }
+    });
+
+    return items;
   }
 
   moveCursorTo(position: number) {
@@ -69,16 +77,11 @@ export default class BasicEditorDriver implements EditorDriverInterface {
     this.insertBetween(pos, pos, text);
   }
 
-  insertBetween(start: number, end: number, text: string) {
-    const value = this.el.value;
-
-    const before = value.slice(0, start);
-    const after = value.slice(end);
-
-    this.setValue(`${before}${text}${after}`);
+  insertBetween(selectionStart: number, selectionEnd: number, text: string) {
+    insertText(this.el, { text, selectionStart, selectionEnd });
 
     // Move the textarea cursor to the end of the content we just inserted.
-    this.moveCursorTo(start + text.length);
+    this.moveCursorTo(selectionStart + text.length);
   }
 
   replaceBeforeCursor(start: number, text: string) {

framework/core/js/src/common/utils/insertText.ts

@@ -0,0 +1,40 @@
+/*
+ * Original Copyright GitHub, Inc. Licensed under the MIT License.
+ * See license text at https://github.com/github/markdown-toolbar-element/blob/master/LICENSE.
+ */
+
+export interface SelectionRange {
+  text: string;
+  selectionStart: number | undefined;
+  selectionEnd: number | undefined;
+}
+
+let canInsertText: boolean | null = null;
+
+export default function insertText(textarea: HTMLTextAreaElement, { text, selectionStart, selectionEnd }: SelectionRange) {
+  const originalSelectionStart = textarea.selectionStart;
+  const before = textarea.value.slice(0, originalSelectionStart);
+  const after = textarea.value.slice(textarea.selectionEnd);
+
+  if (selectionStart != null && selectionEnd != null) {
+    textarea.setSelectionRange(selectionStart, selectionEnd + 1);
+  } else {
+    textarea.setSelectionRange(originalSelectionStart, textarea.selectionEnd);
+  }
+  textarea.focus();
+
+  if (canInsertText === null || canInsertText === true) {
+    textarea.contentEditable = 'true';
+    canInsertText = document.execCommand('insertText', false, text);
+    textarea.contentEditable = 'false';
+  }
+
+  if (canInsertText && !textarea.value.slice(0, textarea.selectionStart).endsWith(text)) {
+    canInsertText = false;
+  }
+
+  if (!canInsertText) {
+    textarea.value = before + text + after;
+    textarea.dispatchEvent(new CustomEvent('input', { bubbles: true, cancelable: true }));
+  }
+}

framework/core/js/src/common/utils/styleSelectedText.ts

@@ -0,0 +1,262 @@
+/*
+ * Original Copyright GitHub, Inc. Licensed under the MIT License.
+ * See license text at https://github.com/github/markdown-toolbar-element/blob/master/LICENSE.
+ */
+
+import insertText, { SelectionRange } from './insertText';
+
+interface StyleArgs {
+  prefix: string;
+  suffix: string;
+  blockPrefix: string;
+  blockSuffix: string;
+  multiline: boolean;
+  replaceNext: string;
+  prefixSpace: boolean;
+  scanFor: string;
+  surroundWithNewlines: boolean;
+  orderedList: boolean;
+  trimFirst: boolean;
+}
+
+const defaults: StyleArgs = {
+  prefix: '',
+  suffix: '',
+  blockPrefix: '',
+  blockSuffix: '',
+  multiline: false,
+  replaceNext: '',
+  prefixSpace: false,
+  scanFor: '',
+  surroundWithNewlines: false,
+  orderedList: false,
+  trimFirst: false,
+};
+
+export default function styleSelectedText(textarea: HTMLTextAreaElement, styleArgs: StyleArgs) {
+  // Next 2 lines are added
+  textarea.focus();
+  styleArgs = Object.assign({}, defaults, styleArgs);
+  // Prev 2 lines are added
+  const text = textarea.value.slice(textarea.selectionStart, textarea.selectionEnd);
+
+  let result;
+  if (styleArgs.orderedList) {
+    result = orderedList(textarea);
+  } else if (styleArgs.multiline && isMultipleLines(text)) {
+    result = multilineStyle(textarea, styleArgs);
+  } else {
+    result = blockStyle(textarea, styleArgs);
+  }
+
+  insertText(textarea, result);
+}
+
+function isMultipleLines(string: string): boolean {
+  return string.trim().split('\n').length > 1;
+}
+
+function repeat(string: string, n: number): string {
+  return Array(n + 1).join(string);
+}
+
+function wordSelectionStart(text: string, i: number): number {
+  let index = i;
+  while (text[index] && text[index - 1] != null && !text[index - 1].match(/\s/)) {
+    index--;
+  }
+  return index;
+}
+
+function wordSelectionEnd(text: string, i: number, multiline: boolean): number {
+  let index = i;
+  const breakpoint = multiline ? /\n/ : /\s/;
+  while (text[index] && !text[index].match(breakpoint)) {
+    index++;
+  }
+  return index;
+}
+
+function expandSelectedText(textarea: HTMLTextAreaElement, prefixToUse: string, suffixToUse: string, multiline = false): string {
+  if (textarea.selectionStart === textarea.selectionEnd) {
+    textarea.selectionStart = wordSelectionStart(textarea.value, textarea.selectionStart);
+    textarea.selectionEnd = wordSelectionEnd(textarea.value, textarea.selectionEnd, multiline);
+  } else {
+    const expandedSelectionStart = textarea.selectionStart - prefixToUse.length;
+    const expandedSelectionEnd = textarea.selectionEnd + suffixToUse.length;
+    const beginsWithPrefix = textarea.value.slice(expandedSelectionStart, textarea.selectionStart) === prefixToUse;
+    const endsWithSuffix = textarea.value.slice(textarea.selectionEnd, expandedSelectionEnd) === suffixToUse;
+    if (beginsWithPrefix && endsWithSuffix) {
+      textarea.selectionStart = expandedSelectionStart;
+      textarea.selectionEnd = expandedSelectionEnd;
+    }
+  }
+  return textarea.value.slice(textarea.selectionStart, textarea.selectionEnd);
+}
+
+interface Newlines {
+  newlinesToAppend: string;
+  newlinesToPrepend: string;
+}
+
+function newlinesToSurroundSelectedText(textarea: HTMLTextAreaElement): Newlines {
+  const beforeSelection = textarea.value.slice(0, textarea.selectionStart);
+  const afterSelection = textarea.value.slice(textarea.selectionEnd);
+
+  const breaksBefore = beforeSelection.match(/\n*$/);
+  const breaksAfter = afterSelection.match(/^\n*/);
+  const newlinesBeforeSelection = breaksBefore ? breaksBefore[0].length : 0;
+  const newlinesAfterSelection = breaksAfter ? breaksAfter[0].length : 0;
+
+  let newlinesToAppend;
+  let newlinesToPrepend;
+
+  if (beforeSelection.match(/\S/) && newlinesBeforeSelection < 2) {
+    newlinesToAppend = repeat('\n', 2 - newlinesBeforeSelection);
+  }
+
+  if (afterSelection.match(/\S/) && newlinesAfterSelection < 2) {
+    newlinesToPrepend = repeat('\n', 2 - newlinesAfterSelection);
+  }
+
+  if (newlinesToAppend == null) {
+    newlinesToAppend = '';
+  }
+
+  if (newlinesToPrepend == null) {
+    newlinesToPrepend = '';
+  }
+
+  return { newlinesToAppend, newlinesToPrepend };
+}
+
+function blockStyle(textarea: HTMLTextAreaElement, arg: StyleArgs): SelectionRange {
+  let newlinesToAppend;
+  let newlinesToPrepend;
+
+  const { prefix, suffix, blockPrefix, blockSuffix, replaceNext, prefixSpace, scanFor, surroundWithNewlines } = arg;
+  const originalSelectionStart = textarea.selectionStart;
+  const originalSelectionEnd = textarea.selectionEnd;
+
+  let selectedText = textarea.value.slice(textarea.selectionStart, textarea.selectionEnd);
+  let prefixToUse = isMultipleLines(selectedText) && blockPrefix.length > 0 ? `${blockPrefix}\n` : prefix;
+  let suffixToUse = isMultipleLines(selectedText) && blockSuffix.length > 0 ? `\n${blockSuffix}` : suffix;
+
+  if (prefixSpace) {
+    const beforeSelection = textarea.value[textarea.selectionStart - 1];
+    if (textarea.selectionStart !== 0 && beforeSelection != null && !beforeSelection.match(/\s/)) {
+      prefixToUse = ` ${prefixToUse}`;
+    }
+  }
+  selectedText = expandSelectedText(textarea, prefixToUse, suffixToUse, arg.multiline);
+  let selectionStart = textarea.selectionStart;
+  let selectionEnd = textarea.selectionEnd;
+  const hasReplaceNext = replaceNext.length > 0 && suffixToUse.indexOf(replaceNext) > -1 && selectedText.length > 0;
+  if (surroundWithNewlines) {
+    const ref = newlinesToSurroundSelectedText(textarea);
+    newlinesToAppend = ref.newlinesToAppend;
+    newlinesToPrepend = ref.newlinesToPrepend;
+    prefixToUse = newlinesToAppend + prefix;
+    suffixToUse += newlinesToPrepend;
+  }
+
+  if (selectedText.startsWith(prefixToUse) && selectedText.endsWith(suffixToUse)) {
+    const replacementText = selectedText.slice(prefixToUse.length, selectedText.length - suffixToUse.length);
+    if (originalSelectionStart === originalSelectionEnd) {
+      let position = originalSelectionStart - prefixToUse.length;
+      position = Math.max(position, selectionStart);
+      position = Math.min(position, selectionStart + replacementText.length);
+      selectionStart = selectionEnd = position;
+    } else {
+      selectionEnd = selectionStart + replacementText.length;
+    }
+    return { text: replacementText, selectionStart, selectionEnd };
+  } else if (!hasReplaceNext) {
+    let replacementText = prefixToUse + selectedText + suffixToUse;
+    selectionStart = originalSelectionStart + prefixToUse.length;
+    selectionEnd = originalSelectionEnd + prefixToUse.length;
+    const whitespaceEdges = selectedText.match(/^\s*|\s*$/g);
+    if (arg.trimFirst && whitespaceEdges) {
+      const leadingWhitespace = whitespaceEdges[0] || '';
+      const trailingWhitespace = whitespaceEdges[1] || '';
+      replacementText = leadingWhitespace + prefixToUse + selectedText.trim() + suffixToUse + trailingWhitespace;
+      selectionStart += leadingWhitespace.length;
+      selectionEnd -= trailingWhitespace.length;
+    }
+    return { text: replacementText, selectionStart, selectionEnd };
+  } else if (scanFor.length > 0 && selectedText.match(scanFor)) {
+    suffixToUse = suffixToUse.replace(replaceNext, selectedText);
+    const replacementText = prefixToUse + suffixToUse;
+    selectionStart = selectionEnd = selectionStart + prefixToUse.length;
+    return { text: replacementText, selectionStart, selectionEnd };
+  } else {
+    const replacementText = prefixToUse + selectedText + suffixToUse;
+    selectionStart = selectionStart + prefixToUse.length + selectedText.length + suffixToUse.indexOf(replaceNext);
+    selectionEnd = selectionStart + replaceNext.length;
+    return { text: replacementText, selectionStart, selectionEnd };
+  }
+}
+
+function multilineStyle(textarea: HTMLTextAreaElement, arg: StyleArgs) {
+  const { prefix, suffix, surroundWithNewlines } = arg;
+  let text = textarea.value.slice(textarea.selectionStart, textarea.selectionEnd);
+  let selectionStart = textarea.selectionStart;
+  let selectionEnd = textarea.selectionEnd;
+  const lines = text.split('\n');
+  const undoStyle = lines.every((line) => line.startsWith(prefix) && line.endsWith(suffix));
+
+  if (undoStyle) {
+    text = lines.map((line) => line.slice(prefix.length, line.length - suffix.length)).join('\n');
+    selectionEnd = selectionStart + text.length;
+  } else {
+    text = lines.map((line) => prefix + line + suffix).join('\n');
+    if (surroundWithNewlines) {
+      const { newlinesToAppend, newlinesToPrepend } = newlinesToSurroundSelectedText(textarea);
+      selectionStart += newlinesToAppend.length;
+      selectionEnd = selectionStart + text.length;
+      text = newlinesToAppend + text + newlinesToPrepend;
+    }
+  }
+
+  return { text, selectionStart, selectionEnd };
+}
+
+function orderedList(textarea: HTMLTextAreaElement): SelectionRange {
+  const orderedListRegex = /^\d+\.\s+/;
+  const noInitialSelection = textarea.selectionStart === textarea.selectionEnd;
+  let selectionEnd;
+  let selectionStart;
+  let text = textarea.value.slice(textarea.selectionStart, textarea.selectionEnd);
+  let textToUnstyle = text;
+  let lines = text.split('\n');
+  let startOfLine, endOfLine;
+  if (noInitialSelection) {
+    const linesBefore = textarea.value.slice(0, textarea.selectionStart).split(/\n/);
+    startOfLine = textarea.selectionStart - linesBefore[linesBefore.length - 1].length;
+    endOfLine = wordSelectionEnd(textarea.value, textarea.selectionStart, true);
+    textToUnstyle = textarea.value.slice(startOfLine, endOfLine);
+  }
+  const linesToUnstyle = textToUnstyle.split('\n');
+  const undoStyling = linesToUnstyle.every((line) => orderedListRegex.test(line));
+
+  if (undoStyling) {
+    lines = linesToUnstyle.map((line) => line.replace(orderedListRegex, ''));
+    text = lines.join('\n');
+    if (noInitialSelection && startOfLine && endOfLine) {
+      const lengthDiff = linesToUnstyle[0].length - lines[0].length;
+      selectionStart = selectionEnd = textarea.selectionStart - lengthDiff;
+      textarea.selectionStart = startOfLine;
+      textarea.selectionEnd = endOfLine;
+    }
+  } else {
+    lines = numberedLines(lines);
+    text = lines.join('\n');
+    const { newlinesToAppend, newlinesToPrepend } = newlinesToSurroundSelectedText(textarea);
+    selectionStart = textarea.selectionStart + newlinesToAppend.length;
+    selectionEnd = selectionStart + text.length;
+    if (noInitialSelection) selectionStart = selectionEnd;
+    text = newlinesToAppend + text + newlinesToPrepend;
+  }
+
+  return { text, selectionStart, selectionEnd };
+}