feat(highlights): Scroll to highlight annotation

src/@types/model.ts

@@ -41,6 +41,8 @@ export interface Position {
     y: number;
 }
 
+export type Shape = Required<DOMRectInit>;
+
 export interface User {
     id: string;
     login: string;

src/document/DocumentAnnotator.ts

@@ -1,5 +1,6 @@
 import BaseAnnotator, { Options } from '../common/BaseAnnotator';
 import BaseManager from '../common/BaseManager';
+import { centerHighlight, isHighlight } from '../highlight/highlightUtil';
 import { centerRegion, isRegion, RegionManager } from '../region';
 import { Event } from '../@types';
 import { getAnnotation } from '../store/annotations';
@@ -145,6 +146,10 @@ export default class DocumentAnnotator extends BaseAnnotator {
             scrollToLocation(this.annotatedEl, annotationPageEl, {
                 offsets: centerRegion(annotation.target.shape),
             });
+        } else if (isHighlight(annotation)) {
+            scrollToLocation(this.annotatedEl, annotationPageEl, {
+                offsets: centerHighlight(annotation.target.shapes),
+            });
         }
     }
 }

src/document/__tests__/DocumentAnnotator-test.ts

@@ -3,6 +3,7 @@ import DocumentAnnotator from '../DocumentAnnotator';
 import HighlightListener from '../../highlight/HighlightListener';
 import RegionManager from '../../region/RegionManager';
 import { Annotation, Event } from '../../@types';
+import { annotation as highlight } from '../../highlight/__mocks__/data';
 import { annotations as regions } from '../../region/__mocks__/data';
 import { fetchAnnotationsAction } from '../../store';
 import { HighlightManager } from '../../highlight';
@@ -39,7 +40,7 @@ describe('DocumentAnnotator', () => {
     };
 
     const payload = {
-        entries: regions as Annotation[],
+        entries: [...regions, highlight] as Annotation[],
         limit: 1000,
         next_marker: null,
         previous_marker: null,
@@ -263,5 +264,13 @@ describe('DocumentAnnotator', () => {
             annotator.scrollToAnnotation(null);
             expect(scrollToLocation).not.toHaveBeenCalled();
         });
+
+        test('should call scrollToLocation for highlight annotations', () => {
+            const parentEl = annotator.annotatedEl as HTMLElement;
+            const referenceEl = parentEl.querySelector('[data-page-number="1"]');
+
+            annotator.scrollToAnnotation('223');
+            expect(scrollToLocation).toHaveBeenCalledWith(parentEl, referenceEl, { offsets: { x: 15, y: 10 } });
+        });
     });
 });

src/highlight/__tests__/highlightUtil-test.ts

@@ -0,0 +1,44 @@
+import { centerHighlight, getBoundingRect } from '../highlightUtil';
+import { Shape } from '../../@types';
+
+const shape1: Shape = {
+    height: 10,
+    width: 10,
+    x: 0,
+    y: 0,
+};
+
+const shape2: Shape = {
+    height: 10,
+    width: 20,
+    x: 10,
+    y: 10,
+};
+
+describe('highlightUtil', () => {
+    describe('getBoundingRect()', () => {
+        test('should be the same rect for a single shape', () => {
+            expect(getBoundingRect([shape1])).toEqual(shape1);
+        });
+
+        test('should get the bounding rect for multiple shapes', () => {
+            expect(getBoundingRect([shape1, shape2])).toEqual({
+                height: 20,
+                width: 30,
+                x: 0,
+                y: 0,
+            });
+        });
+    });
+
+    describe('centerHighlight()', () => {
+        test.each`
+            shapes              | expectedCenter
+            ${[shape1]}         | ${{ x: 5, y: 5 }}
+            ${[shape2]}         | ${{ x: 20, y: 15 }}
+            ${[shape1, shape2]} | ${{ x: 15, y: 10 }}
+        `('should get the center of the highlight to be $expectedCenter', ({ shapes, expectedCenter }) => {
+            expect(centerHighlight(shapes)).toEqual(expectedCenter);
+        });
+    });
+});

src/highlight/highlightUtil.ts

@@ -1,4 +1,59 @@
-import { Annotation, AnnotationHighlight, Type } from '../@types';
+import { Annotation, AnnotationHighlight, Position, Shape, Type } from '../@types';
+
+export const getBoundingRect = (shapes: Shape[]): Shape => {
+    let minX = Number.MAX_VALUE;
+    let minY = Number.MAX_VALUE;
+    let maxX = Number.MIN_VALUE;
+    let maxY = Number.MIN_VALUE;
+
+    shapes.forEach(({ height, width, x, y }) => {
+        const x2 = x + width;
+        const y2 = y + height;
+
+        if (x < minX) {
+            minX = x;
+        }
+
+        if (y < minY) {
+            minY = y;
+        }
+
+        if (x2 > maxX) {
+            maxX = x2;
+        }
+
+        if (y2 > maxY) {
+            maxY = y2;
+        }
+    });
+
+    return {
+        x: minX,
+        y: minY,
+        width: maxX - minX,
+        height: maxY - minY,
+    };
+};
+
+const centerShape = (shape: Shape): Position => {
+    const { height, width } = shape;
+
+    return {
+        x: width / 2,
+        y: height / 2,
+    };
+};
+
+export const centerHighlight = (shapes: Shape[]): Position => {
+    const boundingShape = getBoundingRect(shapes);
+    const { x: shapeX, y: shapeY } = boundingShape;
+    const { x: centerX, y: centerY } = centerShape(boundingShape);
+
+    return {
+        x: centerX + shapeX,
+        y: centerY + shapeY,
+    };
+};
 
 export function isHighlight(annotation: Annotation): annotation is AnnotationHighlight {
     return annotation?.target?.type === Type.highlight;

src/region/RegionAnnotation.tsx

@@ -4,7 +4,8 @@ import classNames from 'classnames';
 import noop from 'lodash/noop';
 import { getIsCurrentFileVersion } from '../store';
 import { MOUSE_PRIMARY } from '../constants';
-import { Shape, styleShape } from './regionUtil';
+import { Shape } from '../@types';
+import { styleShape } from './regionUtil';
 import './RegionAnnotation.scss';
 
 type Props = {

src/region/RegionRect.tsx

@@ -1,6 +1,7 @@
 import * as React from 'react';
 import classNames from 'classnames';
-import { Shape, styleShape } from './regionUtil';
+import { Shape } from '../@types';
+import { styleShape } from './regionUtil';
 import './RegionRect.scss';
 
 type Props = {

src/region/regionUtil.ts

@@ -1,5 +1,5 @@
 import * as React from 'react';
-import { Annotation, AnnotationRegion, Position } from '../@types';
+import { Annotation, AnnotationRegion, Position, Shape } from '../@types';
 import { invertYCoordinate, Point, rotatePoint, translatePoint } from './transformUtil';
 
 // Possible rotation values as supplied by box-content-preview
@@ -15,13 +15,6 @@ export type Dimensions = {
     width: number;
 };
 
-export type Shape = {
-    height: number;
-    width: number;
-    x: number;
-    y: number;
-};
-
 export type Translation = {
     dx?: number;
     dy?: number;

src/store/selection/actions.ts

@@ -1,5 +1,6 @@
 import { createAction } from '@reduxjs/toolkit';
-import { DOMRectMini, SelectionItem } from './types';
+import { SelectionItem } from './types';
+import { Shape } from '../../@types';
 
 export type SelectionArg = {
     location: number;
@@ -10,7 +11,7 @@ type Payload = {
     payload: SelectionItem | null;
 };
 
-export const getDOMRectMini = ({ height, width, x, y }: DOMRect): DOMRectMini => ({
+export const getShape = ({ height, width, x, y }: DOMRect): Shape => ({
     height,
     width,
     x,
@@ -30,9 +31,9 @@ export const setSelectionAction = createAction(
 
         return {
             payload: {
-                boundingRect: getDOMRectMini(range.getBoundingClientRect()),
+                boundingRect: getShape(range.getBoundingClientRect()),
                 location,
-                rects: Array.from(range.getClientRects()).map(getDOMRectMini),
+                rects: Array.from(range.getClientRects()).map(getShape),
             },
         };
     },

src/store/selection/types.ts

@@ -1,11 +1,11 @@
-export type DOMRectMini = Required<DOMRectInit>;
+import { Shape } from '../../@types';
 
 export type SelectionState = {
     selection: SelectionItem | null;
 };
 
 export type SelectionItem = {
-    boundingRect: DOMRectMini;
+    boundingRect: Shape;
     location: number;
-    rects: Array<DOMRectMini>;
+    rects: Array<Shape>;
 };