Soft line boundaries & debug mode improvements

src/json-crdt-extensions/peritext/Peritext.ts

@@ -8,7 +8,7 @@ import {Slices} from './slice/Slices';
 import {LocalSlices} from './slice/LocalSlices';
 import {Overlay} from './overlay/Overlay';
 import {Chars} from './constants';
-import {interval} from '../../json-crdt-patch/clock';
+import {interval, tick} from '../../json-crdt-patch/clock';
 import {Model, type StrApi} from '../../json-crdt/model';
 import {CONST, updateNum} from '../../json-hash';
 import {SESSION} from '../../json-crdt-patch/constants';
@@ -22,6 +22,7 @@ import type {MarkerSlice} from './slice/MarkerSlice';
 import type {SliceSchema, SliceType} from './slice/types';
 import type {SchemaToJsonNode} from '../../json-crdt/schema/types';
 import type {AbstractRga} from '../../json-crdt/nodes/rga';
+import type {ChunkSlice} from './util/ChunkSlice';
 
 const EXTRA_SLICES_SCHEMA = s.vec(s.arr<SliceSchema>([]));
 
@@ -183,6 +184,14 @@ export class Peritext<T = string> implements Printable {
     return Range.from(this.str, p1, p2);
   }
 
+  public rangeFromChunkSlice(slice: ChunkSlice<T>): Range<T> {
+    const startId = slice.off === 0 ? slice.chunk.id : tick(slice.chunk.id, slice.off);
+    const endId = tick(slice.chunk.id, slice.off + slice.len - 1);
+    const start = this.point(startId, Anchor.Before);
+    const end = this.point(endId, Anchor.After);
+    return this.range(start, end);
+  }
+
   /**
    * Creates a range from two points, the points have to be in the correct
    * order.

src/json-crdt-extensions/peritext/editor/Editor.ts

@@ -21,7 +21,16 @@ import type {Peritext} from '../Peritext';
 import type {ChunkSlice} from '../util/ChunkSlice';
 import type {MarkerSlice} from '../slice/MarkerSlice';
 import type {SliceRegistry} from '../registry/SliceRegistry';
-import type {CharIterator, CharPredicate, Position, TextRangeUnit, ViewStyle, ViewRange, ViewSlice} from './types';
+import type {
+  CharIterator,
+  CharPredicate,
+  Position,
+  TextRangeUnit,
+  ViewStyle,
+  ViewRange,
+  ViewSlice,
+  EditorUi,
+} from './types';
 
 /**
  * For inline boolean ("Overwrite") slices, both range endpoints should be
@@ -468,7 +477,7 @@ export class Editor<T = string> implements Printable {
    * @param unit The unit of move per step: "char", "word", "line", etc.
    * @returns The destination point after the move.
    */
-  public skip(point: Point<T>, steps: number, unit: TextRangeUnit): Point<T> {
+  public skip(point: Point<T>, steps: number, unit: TextRangeUnit, ui?: EditorUi<T>): Point<T> {
     if (!steps) return point;
     switch (unit) {
       case 'point': {
@@ -485,10 +494,13 @@ export class Editor<T = string> implements Printable {
         return point;
       }
       case 'line': {
-        if (steps > 0) for (let i = 0; i < steps; i++) point = this.eol(point);
-        else for (let i = 0; i < -steps; i++) point = this.bol(point);
+        if (steps > 0) for (let i = 0; i < steps; i++) point = ui?.eol?.(point, 1) ?? this.eol(point);
+        else for (let i = 0; i < -steps; i++) point = ui?.eol?.(point, -1) ?? this.bol(point);
         return point;
       }
+      case 'vert': {
+        return ui?.vert?.(point, steps) || point;
+      }
       case 'block': {
         if (steps > 0) for (let i = 0; i < steps; i++) point = this.eob(point);
         else for (let i = 0; i < -steps; i++) point = this.bob(point);
@@ -507,26 +519,32 @@ export class Editor<T = string> implements Printable {
    * @param endpoint 0 for "focus", 1 for "anchor", 2 for both.
    * @param collapse Whether to collapse the range to a single point.
    */
-  public move(steps: number, unit: TextRangeUnit, endpoint: 0 | 1 | 2 = 0, collapse: boolean = true): void {
+  public move(
+    steps: number,
+    unit: TextRangeUnit,
+    endpoint: 0 | 1 | 2 = 0,
+    collapse: boolean = true,
+    ui?: EditorUi<T>,
+  ): void {
     this.forCursor((cursor) => {
       switch (endpoint) {
         case 0: {
           let point = cursor.focus();
-          point = this.skip(point, steps, unit);
+          point = this.skip(point, steps, unit, ui);
           if (collapse) cursor.set(point);
           else cursor.setEndpoint(point, 0);
           break;
         }
         case 1: {
           let point = cursor.anchor();
-          point = this.skip(point, steps, unit);
+          point = this.skip(point, steps, unit, ui);
           if (collapse) cursor.set(point);
           else cursor.setEndpoint(point, 1);
           break;
         }
         case 2: {
-          const start = this.skip(cursor.start, steps, unit);
-          const end = collapse ? start.clone() : this.skip(cursor.end, steps, unit);
+          const start = this.skip(cursor.start, steps, unit, ui);
+          const end = collapse ? start.clone() : this.skip(cursor.end, steps, unit, ui);
           cursor.set(start, end);
           break;
         }
@@ -572,24 +590,24 @@ export class Editor<T = string> implements Printable {
    * @param unit Unit of the range expansion.
    * @returns Range which contains the specified unit.
    */
-  public range(point: Point<T>, unit: TextRangeUnit): Range<T> | undefined {
+  public range(point: Point<T>, unit: TextRangeUnit, ui?: EditorUi<T>): Range<T> | undefined {
     if (unit === 'word') return this.rangeWord(point);
-    const point1 = this.skip(point, -1, unit);
-    const point2 = this.skip(point, 1, unit);
+    const point1 = this.skip(point, -1, unit, ui);
+    const point2 = this.skip(point, 1, unit, ui);
     return this.txt.range(point1, point2);
   }
 
-  public select(unit: TextRangeUnit): void {
+  public select(unit: TextRangeUnit, ui?: EditorUi<T>): void {
     this.forCursor((cursor) => {
-      const range = this.range(cursor.start, unit);
+      const range = this.range(cursor.start, unit, ui);
       if (range) cursor.set(range.start, range.end, CursorAnchor.Start);
       else this.delCursors;
     });
   }
 
-  public selectAt(at: Position<T>, unit: TextRangeUnit | ''): void {
+  public selectAt(at: Position<T>, unit: TextRangeUnit | '', ui?: EditorUi<T>): void {
     this.cursor.set(this.point(at));
-    if (unit) this.select(unit);
+    if (unit) this.select(unit, ui);
   }
 
   // --------------------------------------------------------------- formatting

src/json-crdt-extensions/peritext/editor/types.ts

@@ -8,10 +8,44 @@ export type CharIterator<T> = UndefIterator<ChunkSlice<T>>;
 export type CharPredicate<T> = (char: T) => boolean;
 
 export type Position<T = string> = number | [at: number, anchor: 0 | 1] | Point<T>;
-export type TextRangeUnit = 'point' | 'char' | 'word' | 'line' | 'block' | 'all';
+export type TextRangeUnit = 'point' | 'char' | 'word' | 'line' | 'vert' | 'block' | 'all';
 
 export type ViewRange = [text: string, textPosition: number, slices: ViewSlice[]];
 
 export type ViewSlice = [header: number, x1: number, x2: number, type: SliceType, data?: unknown];
 
 export type ViewStyle = [behavior: SliceBehavior, type: SliceType, data?: unknown];
+
+/**
+ * UI API which can be injected during various methods of the editor. Used to
+ * perform editor function while taking into account the visual representation
+ * of the document, such as word wrapping.
+ */
+export interface EditorUi<T = string> {
+  /**
+   * Visually skips to the end or beginning of the line. Visually as in, it will
+   * respect the visual line breaks created by word wrapping.
+   *
+   * Skips just one line, regardless of the magnitude of the `steps` parameter.
+   *
+   * @param point The point from which to start skipping.
+   * @param steps The direction to skip. Positive for forward, negative for
+   *     backward. Does not respect the magnitude of the steps, always performs
+   *     one step.
+   * @returns The point after skipping the specified number of lines, or
+   *     undefined if no such point exists.
+   */
+  eol?(point: Point<T>, steps: number): Point<T> | undefined;
+
+  /**
+   * Used when user presses "ArrowUp" or "ArrowDown" keys. It will skip to the
+   * position in the next visual line, while trying to preserve the horizontal
+   * offset from the beginning of the line.
+   *
+   * @param point The point from which to start skipping.
+   * @param steps Number of lines to skip.
+   * @returns The point after skipping the specified number of lines, or
+   *     undefined if no such point exists.
+   */
+  vert?(point: Point<T>, steps: number): Point<T> | undefined;
+}

src/json-crdt-extensions/peritext/rga/Point.ts

@@ -150,6 +150,18 @@ export class Point<T = string> implements Pick<Stateful, 'refresh'>, Printable {
     return this.anchor === Anchor.Before ? pos : pos + 1;
   }
 
+  /**
+   * @returns Returns `true` if the point is at the very start of the string, i.e.
+   *     there are no visible characters before it.
+   */
+  public isStart(): boolean {
+    const chunk = this.chunk();
+    if (!chunk) return true;
+    if (!chunk.del && chunk.id.time < this.id.time) return false;
+    const l = chunk.l;
+    return l ? !l.len : true;
+  }
+
   /**
    * Goes to the next visible character in the string. The `move` parameter
    * specifies how many characters to move the cursor by. If the cursor reaches

src/json-crdt-peritext-ui/__demos__/components/App.tsx

@@ -7,6 +7,7 @@ import {CursorPlugin} from '../../plugins/cursor';
 import {ToolbarPlugin} from '../../plugins/toolbar';
 import {DebugPlugin} from '../../plugins/debug';
 import {BlocksPlugin} from '../../plugins/blocks';
+import {ValueSyncStore} from '../../../util/events/sync-store';
 
 const markdown =
   'The German __automotive sector__ is in the process of *cutting ' +
@@ -36,10 +37,11 @@ export const App: React.FC = () => {
   }, [model]);
 
   const plugins = React.useMemo(() => {
+    const debugEnabled = new ValueSyncStore(false);
     const cursorPlugin = new CursorPlugin();
-    const toolbarPlugin = new ToolbarPlugin();
+    const toolbarPlugin = new ToolbarPlugin({debug: debugEnabled});
     const blocksPlugin = new BlocksPlugin();
-    const debugPlugin = new DebugPlugin({enabled: false});
+    const debugPlugin = new DebugPlugin({enabled: debugEnabled});
     return [cursorPlugin, toolbarPlugin, blocksPlugin, debugPlugin];
   }, []);
 

src/json-crdt-peritext-ui/components/DebugLabel/index.tsx

@@ -0,0 +1,48 @@
+// biome-ignore lint: React is used for JSX
+import * as React from 'react';
+import {rule, theme} from 'nano-theme';
+
+const labelClass = rule({
+  ...theme.font.mono.bold,
+  d: 'flex',
+  ai: 'center',
+  fz: '9px',
+  pd: '0 4px',
+  mr: '-1px',
+  bdrad: '10px',
+  bg: 'rgba(0,0,0)',
+  lh: '14px',
+  h: '14px',
+  col: 'white',
+  bd: '1px solid #fff',
+});
+
+const labelSecondClass = rule({
+  ...theme.font.mono.bold,
+  d: 'flex',
+  fz: '8px',
+  mr: '2px -2px 2px 4px',
+  pd: '0 4px',
+  bdrad: '10px',
+  bg: 'rgba(255,255,255)',
+  lh: '10px',
+  h: '10px',
+  col: '#000',
+});
+
+export interface DebugLabelProps {
+  right?: React.ReactNode;
+  small?: boolean;
+  children?: React.ReactNode;
+}
+
+export const DebugLabel: React.FC<DebugLabelProps> = ({right, small, children}) => {
+  const style = small ? {fontSize: '7px', lineHeight: '10px', height: '10px', padding: '0 2px'} : void 0;
+
+  return (
+    <span className={labelClass} style={style}>
+      {children}
+      {!!right && <span className={labelSecondClass}>{right}</span>}
+    </span>
+  );
+};

src/json-crdt-peritext-ui/dom/CursorController.ts

@@ -5,7 +5,7 @@ import {ValueSyncStore} from '../../util/events/sync-store';
 import type {Printable} from 'tree-dump';
 import type {KeyController} from './KeyController';
 import type {PeritextEventTarget} from '../events/PeritextEventTarget';
-import type {Rect, UiLifeCycles} from './types';
+import type {UiLifeCycles} from './types';
 import type {Peritext} from '../../json-crdt-extensions/peritext';
 import type {Inline} from '../../json-crdt-extensions/peritext/block/Inline';
 
@@ -55,45 +55,6 @@ export class CursorController implements UiLifeCycles, Printable {
     return -1;
   }
 
-  public caretRect(): Rect | undefined {
-    const el = document.getElementById(this.caretId);
-    if (!el) return;
-    const rect = el.getBoundingClientRect();
-    return rect;
-  }
-
-  /**
-   * Find text position at similar x coordinate on the next line.
-   *
-   * @param direction 1 for next line, -1 for previous line.
-   * @returns The position at similar x coordinate on the next line, or
-   *          undefined if not found.
-   *
-   * @todo Implement similar functionality for finding soft line breaks (end
-   *     and start of lines). Or use `.getClientRects()` trick with `Range`
-   *     object, see: https://www.bennadel.com/blog/4310-detecting-rendered-line-breaks-in-a-text-node-in-javascript.htm
-   */
-  public getNextLinePos(direction: 1 | -1 = 1): number | undefined {
-    const rect = this.caretRect();
-    if (!rect) return;
-    const {x, y, width, height} = rect;
-    const halfWidth = width / 2;
-    const halfHeight = height / 2;
-    const currentPos = this.opts.txt.editor.cursor.focus().viewPos();
-    const caretPos = this.posAtPoint(x + halfWidth, y + halfHeight);
-    if (currentPos !== caretPos) return;
-    for (let i = 1; i < 16; i++) {
-      const dy = i * direction * halfHeight;
-      const pos = this.posAtPoint(x + halfWidth, y + dy);
-      if (pos !== -1 && pos !== caretPos) {
-        if (direction < 0) {
-          if (pos < caretPos) return pos;
-        } else if (pos > caretPos) return pos;
-      }
-    }
-    return undefined;
-  }
-
   /** -------------------------------------------------- {@link UiLifeCycles} */
 
   public start(): void {
@@ -201,16 +162,9 @@ export class CursorController implements UiLifeCycles, Printable {
     switch (key) {
       case 'ArrowUp':
       case 'ArrowDown': {
+        event.preventDefault();
         const direction = key === 'ArrowUp' ? -1 : 1;
-        const at = this.getNextLinePos(direction);
-        if (at !== undefined) {
-          event.preventDefault();
-          if (event.shiftKey) {
-            et.cursor({at, edge: 'focus'});
-          } else {
-            et.cursor({at});
-          }
-        }
+        et.move(direction, 'vert', event.shiftKey ? 'focus' : 'both');
         break;
       }
       case 'ArrowLeft':
@@ -219,6 +173,7 @@ export class CursorController implements UiLifeCycles, Printable {
         event.preventDefault();
         if (event.shiftKey) et.move(direction, unit(event) || 'char', 'focus');
         else if (event.metaKey) et.move(direction, 'line');
+        else if (event.altKey && event.ctrlKey) et.move(direction, 'point');
         else if (event.altKey || event.ctrlKey) et.move(direction, 'word');
         else et.move(direction);
         break;