Merge pull request #8361 from weseek/feat/126519-136101-support-scroll-sync

feat: Scroll sync in editor

apps/app/src/components/PageEditor/PageEditor.tsx

@@ -60,7 +60,7 @@ import loggerFactory from '~/utils/logger';
 // import Editor from './Editor';
 import EditorNavbarBottom from './EditorNavbarBottom';
 import Preview from './Preview';
-import scrollSyncHelper from './ScrollSyncHelper';
+import { scrollEditor, scrollPreview } from './ScrollSyncHelper';
 
 import '@growi/editor/dist/style.css';
 
@@ -73,13 +73,10 @@ declare global {
   var globalEmitter: EventEmitter;
 }
 
-
 // for scrolling
-let lastScrolledDateWithCursor: Date | null = null;
 let isOriginOfScrollSyncEditor = false;
 let isOriginOfScrollSyncPreview = false;
 
-
 type Props = {
   visibility?: boolean,
 }
@@ -356,97 +353,38 @@ export const PageEditor = React.memo((props: Props): JSX.Element => {
     return AcceptedUploadFileType.IMAGE;
   }, [isUploadAllFileAllowed, isUploadEnabled]);
 
-  const scrollPreviewByEditorLine = useCallback((line: number) => {
-    if (previewRef.current == null) {
+
+  const scrollEditorHandler = useCallback(() => {
+    if (codeMirrorEditor?.view?.scrollDOM == null || previewRef.current == null) {
       return;
     }
 
-    // prevent circular invocation
     if (isOriginOfScrollSyncPreview) {
-      isOriginOfScrollSyncPreview = false; // turn off the flag
+      isOriginOfScrollSyncPreview = false;
       return;
     }
 
-    // turn on the flag
     isOriginOfScrollSyncEditor = true;
-    scrollSyncHelper.scrollPreview(previewRef.current, line);
-  }, []);
-  const scrollPreviewByEditorLineWithThrottle = useMemo(() => throttle(20, scrollPreviewByEditorLine), [scrollPreviewByEditorLine]);
-
-  /**
-   * the scroll event handler from codemirror
-   * @param {any} data {left, top, width, height, clientWidth, clientHeight} object that represents the current scroll position,
-   *                    the size of the scrollable area, and the size of the visible area (minus scrollbars).
-   *                    And data.line is also available that is added by Editor component
-   * @see https://codemirror.net/doc/manual.html#events
-   */
-  const editorScrolledHandler = useCallback(({ line }: { line: number }) => {
-    // prevent scrolling
-    //   if the elapsed time from last scroll with cursor is shorter than 40ms
-    const now = new Date();
-    if (lastScrolledDateWithCursor != null && now.getTime() - lastScrolledDateWithCursor.getTime() < 40) {
-      return;
-    }
+    scrollEditor(codeMirrorEditor.view.scrollDOM, previewRef.current);
+  }, [codeMirrorEditor, previewRef]);
 
-    scrollPreviewByEditorLineWithThrottle(line);
-  }, [scrollPreviewByEditorLineWithThrottle]);
+  const scrollEditorHandlerThrottle = useMemo(() => throttle(25, scrollEditorHandler), [scrollEditorHandler]);
 
-  /**
-   * scroll Preview element by cursor moving
-   * @param {number} line
-   */
-  const scrollPreviewByCursorMoving = useCallback((line: number) => {
-    if (previewRef.current == null) {
+  const scrollPreviewHandler = useCallback(() => {
+    if (codeMirrorEditor?.view?.scrollDOM == null || previewRef.current == null) {
       return;
     }
 
-    // prevent circular invocation
-    if (isOriginOfScrollSyncPreview) {
-      isOriginOfScrollSyncPreview = false; // turn off the flag
+    if (isOriginOfScrollSyncEditor) {
+      isOriginOfScrollSyncEditor = false;
       return;
     }
 
-    // turn on the flag
-    isOriginOfScrollSyncEditor = true;
-    if (previewRef.current != null) {
-      scrollSyncHelper.scrollPreviewToRevealOverflowing(previewRef.current, line);
-    }
-  }, []);
-  const scrollPreviewByCursorMovingWithThrottle = useMemo(() => throttle(20, scrollPreviewByCursorMoving), [scrollPreviewByCursorMoving]);
-
-  /**
-   * the scroll event handler from codemirror
-   * @param {number} line
-   * @see https://codemirror.net/doc/manual.html#events
-   */
-  const editorScrollCursorIntoViewHandler = useCallback((line: number) => {
-    // record date
-    lastScrolledDateWithCursor = new Date();
-    scrollPreviewByCursorMovingWithThrottle(line);
-  }, [scrollPreviewByCursorMovingWithThrottle]);
-
-  /**
-   * scroll Editor component by scroll event of Preview component
-   * @param {number} offset
-   */
-  // const scrollEditorByPreviewScroll = useCallback((offset: number) => {
-  //   if (editorRef.current == null || previewRef.current == null) {
-  //     return;
-  //   }
-
-  //   // prevent circular invocation
-  //   if (isOriginOfScrollSyncEditor) {
-  //     isOriginOfScrollSyncEditor = false; // turn off the flag
-  //     return;
-  //   }
-
-  //   // turn on the flag
-  //   // eslint-disable-next-line @typescript-eslint/no-unused-vars
-  //   isOriginOfScrollSyncPreview = true;
-
-  //   scrollSyncHelper.scrollEditor(editorRef.current, previewRef.current, offset);
-  // }, []);
-  // const scrollEditorByPreviewScrollWithThrottle = useMemo(() => throttle(20, scrollEditorByPreviewScroll), [scrollEditorByPreviewScroll]);
+    isOriginOfScrollSyncPreview = true;
+    scrollPreview(codeMirrorEditor.view.scrollDOM, previewRef.current);
+  }, [codeMirrorEditor, previewRef]);
+
+  const scrollPreviewHandlerThrottle = useMemo(() => throttle(25, scrollPreviewHandler), [scrollPreviewHandler]);
 
   const afterResolvedHandler = useCallback(async() => {
     // get page data from db
@@ -481,22 +419,6 @@ export const PageEditor = React.memo((props: Props): JSX.Element => {
     codeMirrorEditor?.setCaretLine();
   }, [codeMirrorEditor]);
 
-  // set handler to set caret line
-  useEffect(() => {
-    const handler = (line) => {
-      codeMirrorEditor?.setCaretLine(line);
-
-      if (previewRef.current != null) {
-        scrollSyncHelper.scrollPreview(previewRef.current, line);
-      }
-    };
-    globalEmitter.on('setCaretLine', handler);
-
-    return function cleanup() {
-      globalEmitter.removeListener('setCaretLine', handler);
-    };
-  }, [codeMirrorEditor]);
-
   // set handler to save and return to View
   useEffect(() => {
     globalEmitter.on('saveAndReturnToView', saveAndReturnToViewHandler);
@@ -575,20 +497,19 @@ export const PageEditor = React.memo((props: Props): JSX.Element => {
             onChange={markdownChangedHandler}
             onSave={saveWithShortcut}
             onUpload={uploadHandler}
+            onScroll={scrollEditorHandlerThrottle}
             indentSize={currentIndentSize ?? defaultIndentSize}
             acceptedFileType={acceptedFileType}
           />
         </div>
-        <div className="page-editor-preview-container flex-expand-vert d-none d-lg-flex">
+        <div ref={previewRef} onScroll={scrollPreviewHandlerThrottle} className="page-editor-preview-container flex-expand-vert d-none d-lg-flex">
           <Preview
-            ref={previewRef}
             rendererOptions={rendererOptions}
             markdown={markdownToPreview}
             pagePath={currentPagePath}
             expandContentWidth={shouldExpandContent}
-            // TODO: implement
-            // refs: https://redmine.weseek.co.jp/issues/126519
-            // onScroll={offset => scrollEditorByPreviewScrollWithThrottle(offset)}
+            // TODO: Dynamic changes by height or resizing the last element
+            pastEnd={500}
           />
         </div>
         {/*

apps/app/src/components/PageEditor/Preview.tsx

@@ -17,14 +17,15 @@ type Props = {
   markdown?: string,
   pagePath?: string | null,
   expandContentWidth?: boolean,
+  pastEnd?: number,
   onScroll?: (scrollTop: number) => void,
 }
 
-const Preview = React.forwardRef((props: Props, ref: RefObject<HTMLDivElement>): JSX.Element => {
+const Preview = React.forwardRef((props: Props): JSX.Element => {
 
   const {
     rendererOptions,
-    markdown, pagePath,
+    markdown, pagePath, pastEnd,
     expandContentWidth,
   } = props;
 
@@ -33,12 +34,7 @@ const Preview = React.forwardRef((props: Props, ref: RefObject<HTMLDivElement>):
   return (
     <div
       className={`${moduleClass} ${fluidLayoutClass} ${pagePath === '/Sidebar' ? 'preview-sidebar' : ''}`}
-      ref={ref}
-      onScroll={(event: SyntheticEvent<HTMLDivElement>) => {
-        if (props.onScroll != null) {
-          props.onScroll(event.currentTarget.scrollTop);
-        }
-      }}
+      style={{ paddingBottom: pastEnd }}
     >
       { markdown != null && (
         <RevisionRenderer rendererOptions={rendererOptions} markdown={markdown}></RevisionRenderer>

apps/app/src/components/PageEditor/ScrollSyncHelper.js

@@ -1,206 +0,0 @@
-/**
- * This class is copied from Microsoft/vscode repository
- * @see https://github.com/Microsoft/vscode/blob/0532a3429a18688a0c086a4212e7e5b4888b2a48/extensions/markdown/media/main.js
- */
-class ScrollSyncHelper {
-
-  /**
-   * @typedef {{ element: Element, line: number }} CodeLineElement
-   */
-
-  getCodeLineElements(parentElement) {
-    /** @type {CodeLineElement[]} */
-    let elements;
-    if (!elements) {
-      elements = Array.prototype.map.call(
-        parentElement.getElementsByClassName('has-data-line'),
-        (element) => {
-          const line = +element.getAttribute('data-line');
-          return { element, line };
-        },
-      )
-        .filter((x) => { return !Number.isNaN(x.line) });
-    }
-    return elements;
-  }
-
-  /**
-   * Find the html elements that map to a specific target line in the editor.
-   *
-   * If an exact match, returns a single element. If the line is between elements,
-   * returns the element prior to and the element after the given line.
-   *
-   * @param {Element} element
-   * @param {number} targetLine
-   *
-   * @returns {{ previous: CodeLineElement, next?: CodeLineElement }}
-   */
-  getElementsForSourceLine(element, targetLine) {
-    const lines = this.getCodeLineElements(element);
-    let previous = lines[0] || null;
-    for (const entry of lines) {
-      if (entry.line === targetLine) {
-        return { previous: entry, next: null };
-      }
-      if (entry.line > targetLine) {
-        return { previous, next: entry };
-      }
-      previous = entry;
-    }
-    return { previous };
-  }
-
-  /**
-   * Find the html elements that are at a specific pixel offset on the page.
-   *
-   * @param {Element} parentElement
-   * @param {number} offset
-   *
-   * @returns {{ previous: CodeLineElement, next?: CodeLineElement }}
-   */
-  getLineElementsAtPageOffset(parentElement, offset) {
-    const lines = this.getCodeLineElements(parentElement);
-
-    const position = offset - parentElement.scrollTop + this.getParentElementOffset(parentElement);
-
-    let lo = -1;
-    let hi = lines.length - 1;
-    while (lo + 1 < hi) {
-      const mid = Math.floor((lo + hi) / 2);
-      const bounds = lines[mid].element.getBoundingClientRect();
-      if (bounds.top + bounds.height >= position) {
-        hi = mid;
-      }
-      else {
-        lo = mid;
-      }
-    }
-
-    const hiElement = lines[hi];
-
-    if (hiElement == null) {
-      return {};
-    }
-
-    if (hi >= 1 && hiElement.element.getBoundingClientRect().top > position) {
-      const loElement = lines[lo];
-      const bounds = loElement.element.getBoundingClientRect();
-      const previous = { element: loElement.element, line: loElement.line };
-      if (bounds.height > 0) {
-        previous.line += (position - bounds.top) / (bounds.height);
-      }
-      const next = { element: hiElement.element, line: hiElement.line, fractional: 0 };
-      return { previous, next };
-    }
-
-    const bounds = hiElement.element.getBoundingClientRect();
-    const previous = { element: hiElement.element, line: hiElement.line + (position - bounds.top) / (bounds.height) };
-    return { previous };
-  }
-
-  getEditorLineNumberForPageOffset(parentElement, offset) {
-    const { previous, next } = this.getLineElementsAtPageOffset(parentElement, offset);
-    if (previous != null) {
-      if (next) {
-        const betweenProgress = (
-          offset - parentElement.scrollTop - previous.element.getBoundingClientRect().top)
-          / (next.element.getBoundingClientRect().top - previous.element.getBoundingClientRect().top);
-        return previous.line + betweenProgress * (next.line - previous.line);
-      }
-
-      return previous.line;
-
-    }
-    return null;
-  }
-
-  /**
-   * return the sum of the offset position of parent element and paddingTop
-   * @param {Element} parentElement
-   */
-  getParentElementOffset(parentElement) {
-    const offsetY = parentElement.getBoundingClientRect().top;
-    // get paddingTop
-    const style = window.getComputedStyle(parentElement, null);
-    const paddingTop = +(style.paddingTop.replace('px', ''));
-
-    return offsetY + paddingTop;
-  }
-
-  /**
-   * Attempt to scroll preview element for a source line in the editor.
-   *
-   * @param {Element} previewElement
-   * @param {number} line
-   */
-  scrollPreview(previewElement, line) {
-    const { previous, next } = this.getElementsForSourceLine(previewElement, line);
-    if (previous) {
-      let scrollTo = 0;
-      if (next) {
-        // Between two elements. Go to percentage offset between them.
-        const betweenProgress = (line - previous.line) / (next.line - previous.line);
-        const elementOffset = next.element.getBoundingClientRect().top - previous.element.getBoundingClientRect().top;
-        scrollTo = previous.element.getBoundingClientRect().top + betweenProgress * elementOffset;
-      }
-      else {
-        scrollTo = previous.element.getBoundingClientRect().top;
-      }
-
-      scrollTo -= this.getParentElementOffset(previewElement);
-
-      previewElement.scrollTop += scrollTo;
-    }
-  }
-
-  /**
-   * Attempt to reveal the element that is overflowing from previewElement.
-   *
-   * @param {Element} previewElement
-   * @param {number} line
-   */
-  scrollPreviewToRevealOverflowing(previewElement, line) {
-    // eslint-disable-next-line no-unused-vars
-    const { previous, next } = this.getElementsForSourceLine(previewElement, line);
-    if (previous) {
-      const parentElementOffset = this.getParentElementOffset(previewElement);
-      const prevElmTop = previous.element.getBoundingClientRect().top - parentElementOffset;
-      const prevElmBottom = previous.element.getBoundingClientRect().bottom - parentElementOffset;
-
-      let scrollTo = null;
-      if (prevElmTop < 0) {
-        // set the top of 'previous.element' to the top of 'previewElement'
-        scrollTo = previewElement.scrollTop + prevElmTop;
-      }
-      else if (prevElmBottom > previewElement.clientHeight) {
-        // set the bottom of 'previous.element' to the bottom of 'previewElement'
-        scrollTo = previewElement.scrollTop + prevElmBottom - previewElement.clientHeight + 20;
-      }
-
-      if (scrollTo == null) {
-        return;
-      }
-
-      previewElement.scrollTop = scrollTo;
-    }
-  }
-
-  /**
-   * Attempt to scroll Editor component for the offset of the element in the Preview component.
-   *
-   * @param {Editor} editor
-   * @param {Element} previewElement
-   * @param {number} offset
-   */
-  scrollEditor(editor, previewElement, offset) {
-    let line = this.getEditorLineNumberForPageOffset(previewElement, offset);
-    line = Math.floor(line);
-    editor.setScrollTopByLine(line);
-  }
-
-}
-
-// singleton pattern
-const instance = new ScrollSyncHelper();
-Object.freeze(instance);
-export default instance;

apps/app/src/components/PageEditor/ScrollSyncHelper.ts

@@ -0,0 +1,152 @@
+let defaultTop = 0;
+const padding = 5;
+
+const setDefaultTop = (top: number): void => {
+  defaultTop = top;
+};
+const getDefaultTop = (): number => {
+  return defaultTop + padding;
+};
+
+
+const getDataLine = (element: Element | null): number => {
+  return element ? +(element.getAttribute('data-line') ?? '0') - 1 : 0;
+};
+
+const getEditorElements = (editorRootElement: HTMLElement): Array<Element> => {
+  return Array.from(editorRootElement.getElementsByClassName('cm-line'))
+    .filter((element) => { return !Number.isNaN(element.getAttribute('data-line')) });
+};
+
+const getPreviewElements = (previewRootElement: HTMLElement): Array<Element> => {
+  return Array.from(previewRootElement.getElementsByClassName('has-data-line'))
+    .filter((element) => { return !Number.isNaN(element.getAttribute('data-line')) });
+};
+
+// Ref: https://github.com/mikolalysenko/binary-search-bounds/blob/f436a2a8af11bf3208434e18bbac17e18e7a3a30/search-bounds.js
+const elementBinarySearch = (list: Array<Element>, fn: (index: number) => boolean): number => {
+  let ok = 0;
+  let ng = list.length;
+  while (ok + 1 < ng) {
+    const mid = Math.floor((ok + ng) / 2);
+    if (fn(mid)) {
+      ok = mid;
+    }
+    else {
+      ng = mid;
+    }
+  }
+  return ok;
+};
+
+const findTopElementIndex = (elements: Array<Element>): number => {
+
+  const find = (index: number): boolean => {
+    return elements[index].getBoundingClientRect().top < getDefaultTop();
+  };
+
+  return elementBinarySearch(elements, find);
+};
+
+const findElementIndexFromDataLine = (previewElements: Array<Element>, dataline: number): number => {
+
+  const find = (index: number): boolean => {
+    return getDataLine(previewElements[index]) <= dataline;
+  };
+
+  return elementBinarySearch(previewElements, find);
+};
+
+
+type SourceElement = {
+  start: DOMRect,
+  top: DOMRect,
+  next: DOMRect | undefined,
+}
+
+type TargetElement = {
+  start: DOMRect,
+  next: DOMRect | undefined,
+}
+
+const calcScrollElementToTop = (element: Element): number => {
+  return element.getBoundingClientRect().top - getDefaultTop();
+};
+
+const calcScorllElementByRatio = (sourceElement: SourceElement, targetElement: TargetElement): number => {
+  if (sourceElement.start === sourceElement.next || sourceElement.next == null || targetElement.next == null) {
+    return 0;
+  }
+  const sourceAllHeight = sourceElement.next.top - sourceElement.start.top;
+  const sourceOutHeight = sourceElement.top.top - sourceElement.start.top;
+  const sourceTopHeight = getDefaultTop() - sourceElement.top.top;
+  const sourceRaito = (sourceOutHeight + sourceTopHeight) / sourceAllHeight;
+
+  const targetAllHeight = targetElement.next.top - targetElement.start.top;
+
+  return targetAllHeight * sourceRaito;
+};
+
+
+export const scrollEditor = (editorRootElement: HTMLElement, previewRootElement: HTMLElement): void => {
+
+  setDefaultTop(editorRootElement.getBoundingClientRect().top);
+
+  const editorElements = getEditorElements(editorRootElement);
+  const previewElements = getPreviewElements(previewRootElement);
+
+  const topEditorElementIndex = findTopElementIndex(editorElements);
+  const topPreviewElementIndex = findElementIndexFromDataLine(previewElements, getDataLine(editorElements[topEditorElementIndex]));
+
+  const startEditorElementIndex = findElementIndexFromDataLine(editorElements, getDataLine(previewElements[topPreviewElementIndex]));
+  const nextEditorElementIndex = findElementIndexFromDataLine(editorElements, getDataLine(previewElements[topPreviewElementIndex + 1]));
+
+  let newScrollTop = previewRootElement.scrollTop;
+
+  newScrollTop += calcScrollElementToTop(previewElements[topPreviewElementIndex]);
+  newScrollTop += calcScorllElementByRatio(
+    {
+      start: editorElements[startEditorElementIndex].getBoundingClientRect(),
+      top: editorElements[topEditorElementIndex].getBoundingClientRect(),
+      next: editorElements[nextEditorElementIndex]?.getBoundingClientRect(),
+    },
+    {
+      start: previewElements[topPreviewElementIndex].getBoundingClientRect(),
+      next: previewElements[topPreviewElementIndex + 1]?.getBoundingClientRect(),
+    },
+  );
+
+  previewRootElement.scrollTop = newScrollTop;
+
+};
+
+export const scrollPreview = (editorRootElement: HTMLElement, previewRootElement: HTMLElement): void => {
+
+  setDefaultTop(previewRootElement.getBoundingClientRect().y);
+
+  const previewElements = getPreviewElements(previewRootElement);
+  const editorElements = getEditorElements(editorRootElement);
+
+  const topPreviewElementIndex = findTopElementIndex(previewElements);
+
+  const startEditorElementIndex = findElementIndexFromDataLine(editorElements, getDataLine(previewElements[topPreviewElementIndex]));
+  const nextEditorElementIndex = findElementIndexFromDataLine(editorElements, getDataLine(previewElements[topPreviewElementIndex + 1]));
+
+  let newScrollTop = editorRootElement.scrollTop;
+
+  newScrollTop += calcScrollElementToTop(editorElements[startEditorElementIndex]);
+  newScrollTop += calcScorllElementByRatio(
+    {
+      start: previewElements[topPreviewElementIndex].getBoundingClientRect(),
+      top: previewElements[topPreviewElementIndex].getBoundingClientRect(),
+      next: previewElements[topPreviewElementIndex + 1]?.getBoundingClientRect(),
+    },
+    {
+      start: editorElements[startEditorElementIndex].getBoundingClientRect(),
+      next: editorElements[nextEditorElementIndex]?.getBoundingClientRect(),
+    },
+  );
+
+  editorRootElement.scrollTop = newScrollTop;
+
+};

packages/editor/src/components/CodeMirrorEditor/CodeMirrorEditor.tsx

@@ -25,6 +25,7 @@ type Props = {
   acceptedFileType: AcceptedUploadFileType,
   onChange?: (value: string) => void,
   onUpload?: (files: File[]) => void,
+  onScroll?: () => void,
   indentSize?: number,
 }
 
@@ -34,6 +35,7 @@ export const CodeMirrorEditor = (props: Props): JSX.Element => {
     acceptedFileType,
     onChange,
     onUpload,
+    onScroll,
     indentSize,
   } = props;
 
@@ -100,6 +102,24 @@ export const CodeMirrorEditor = (props: Props): JSX.Element => {
 
   }, [codeMirrorEditor]);
 
+  useEffect(() => {
+
+    const handleScroll = (event: Event) => {
+      event.preventDefault();
+      if (onScroll != null) {
+        onScroll();
+      }
+    };
+
+    const extension = EditorView.domEventHandlers({
+      scroll: handleScroll,
+    });
+
+    const cleanupFunction = codeMirrorEditor?.appendExtensions(extension);
+    return cleanupFunction;
+
+  }, [onScroll, codeMirrorEditor]);
+
   const {
     getRootProps,
     isDragActive,

packages/editor/src/components/CodeMirrorEditorMain.tsx

@@ -1,29 +1,34 @@
 import { useEffect } from 'react';
 
-import type { Extension } from '@codemirror/state';
+import { type Extension } from '@codemirror/state';
 import { keymap, scrollPastEnd } from '@codemirror/view';
 
 import { GlobalCodeMirrorEditorKey, AcceptedUploadFileType } from '../consts';
+import { setDataLine } from '../services/extensions/setDataLine';
 import { useCodeMirrorEditorIsolated } from '../stores';
 
 import { CodeMirrorEditor } from '.';
 
 
 const additionalExtensions: Extension[] = [
-  scrollPastEnd(),
+  [
+    scrollPastEnd(),
+    setDataLine,
+  ],
 ];
 
 type Props = {
   onChange?: (value: string) => void,
   onSave?: () => void,
   onUpload?: (files: File[]) => void,
+  onScroll?: () => void,
   acceptedFileType?: AcceptedUploadFileType,
   indentSize?: number,
 }
 
 export const CodeMirrorEditorMain = (props: Props): JSX.Element => {
   const {
-    onSave, onChange, onUpload, acceptedFileType, indentSize,
+    onSave, onChange, onUpload, onScroll, acceptedFileType, indentSize,
   } = props;
 
   const { data: codeMirrorEditor } = useCodeMirrorEditorIsolated(GlobalCodeMirrorEditorKey.MAIN);
@@ -65,6 +70,7 @@ export const CodeMirrorEditorMain = (props: Props): JSX.Element => {
       editorKey={GlobalCodeMirrorEditorKey.MAIN}
       onChange={onChange}
       onUpload={onUpload}
+      onScroll={onScroll}
       acceptedFileType={acceptedFileTypeNoOpt}
       indentSize={indentSize}
     />

packages/editor/src/services/codemirror-editor/use-codemirror-editor/use-codemirror-editor.ts

@@ -23,6 +23,7 @@ import { useInsertText, type InsertText } from './utils/insert-text';
 import { useReplaceText, type ReplaceText } from './utils/replace-text';
 import { useSetCaretLine, type SetCaretLine } from './utils/set-caret-line';
 
+
 const markdownHighlighting = HighlightStyle.define([
   { tag: tags.heading1, class: 'cm-header-1 cm-header' },
   { tag: tags.heading2, class: 'cm-header-2 cm-header' },

packages/editor/src/services/extensions/setDataLine.ts

@@ -0,0 +1,48 @@
+
+// Ref: https://github.com/uiwjs/react-codemirror/blob/bf3b862923d0cb04ccf4bb9da0791bdc7fd6d29b/extensions/classname/src/index.ts
+
+
+import { RangeSetBuilder } from '@codemirror/state';
+import {
+  EditorView, Decoration, ViewPlugin, DecorationSet, ViewUpdate,
+} from '@codemirror/view';
+
+const stripeDeco = (view: EditorView) => {
+  const builder = new RangeSetBuilder<Decoration>();
+  for (const { from, to } of view.visibleRanges) {
+    for (let pos = from; pos <= to;) {
+      const line = view.state.doc.lineAt(pos);
+      const cls = line.number.toString();
+      builder.add(
+        line.from,
+        line.from,
+        Decoration.line({
+          attributes: { 'data-line': cls },
+        }),
+      );
+      pos = line.to + 1;
+    }
+  }
+  return builder.finish();
+};
+
+export const setDataLine = ViewPlugin.fromClass(
+  class {
+
+    decorations: DecorationSet;
+
+    constructor(view: EditorView) {
+      this.decorations = stripeDeco(view);
+    }
+
+    update(update: ViewUpdate) {
+      if (update.docChanged || update.viewportChanged) {
+        this.decorations = stripeDeco(update.view);
+      }
+    }
+
+  },
+  {
+    decorations: v => v.decorations,
+  },
+);