Bring back waveform for voice messages and retain seeking (#8843)

* Crude way of layering the waveform and seek bar

Not intended for production.

* Use a layout prop instead of something less descriptive

* Fix alignment properly, and play with styles

* Convert back to a ball

* Use `transparent` which makes NVDA happy enough

* Allow keyboards in the seek bar

* Try to make the clock behave more correctly with screen readers

MIDNIGHT

* Remove legacy export

* Remove redundant attr

* Appease the linter

res/css/views/audio_messages/_PlaybackContainer.scss

@@ -52,16 +52,57 @@ limitations under the License.
         padding-left: 8px; // isolate from recording circle / play control
     }
 
-    // For timeline-rendered playback, mirror the values for where the clock is in
-    // the waveform version.
-    .mx_SeekBar {
+    .mx_RecordingPlayback_timelineLayoutMiddle {
         margin-left: 8px;
         margin-right: 6px;
+        position: relative;
+        display: inline-block;
+        flex: 1;
+        height: 30px; // same height as mx_Waveform, needed for automatic vertical centering
 
+        .mx_Waveform {
+            position: absolute;
+            left: 0;
+            top: 0;
+        }
+
+        .mx_SeekBar {
+            position: absolute;
+            left: 0;
+            height: 30px;
+            top: -2px; // visually vertically centered
+
+            // Hide the hairline progress bar since we're at 100% height. Need to have distinct rules
+            // because CSS is weird.
+            background: none;
+            &::before {
+                background: none;
+            }
+            &::-moz-range-progress {
+                background: none;
+            }
+
+            // Make the thumb easier to see. Like the SeekBar original styles, these need to be
+            // distinct. We make it transparent so it doesn't show up on the UI, but also larger
+            // so it's easier to grab by mouse users in some browsers. Most browsers let the user
+            // move and drag the thumb regardless of hitting the thumb, however.
+            &::-webkit-slider-thumb {
+                width: 10px;
+                height: 10px;
+                background-color: transparent;
+            }
+            &::-moz-range-thumb {
+                width: 10px;
+                height: 10px;
+                background-color: transparent;
+            }
+        }
+
+        // For timeline-rendered playback, the clock is on the other side of the waveform.
         & + .mx_Clock {
             text-align: right;
 
-            // Take the padding off the clock because it's accounted for in the seek bar
+            // Take the padding off the clock because it's accounted for by the `timelineLayoutMiddle`
             padding: 0;
         }
     }

src/components/views/audio_messages/Clock.tsx

@@ -18,7 +18,7 @@ import React, { HTMLProps } from "react";
 
 import { formatSeconds } from "../../../DateUtils";
 
-export interface IProps extends Pick<HTMLProps<HTMLSpanElement>, "aria-live"> {
+interface IProps extends Pick<HTMLProps<HTMLSpanElement>, "aria-live" | "role"> {
     seconds: number;
 }
 
@@ -31,14 +31,14 @@ export default class Clock extends React.Component<IProps> {
         super(props);
     }
 
-    shouldComponentUpdate(nextProps: Readonly<IProps>): boolean {
+    public shouldComponentUpdate(nextProps: Readonly<IProps>): boolean {
         const currentFloor = Math.floor(this.props.seconds);
         const nextFloor = Math.floor(nextProps.seconds);
         return currentFloor !== nextFloor;
     }
 
     public render() {
-        return <span aria-live={this.props["aria-live"]} className='mx_Clock'>
+        return <span aria-live={this.props["aria-live"]} role={this.props.role} className='mx_Clock'>
             { formatSeconds(this.props.seconds) }
         </span>;
     }

src/components/views/audio_messages/PlaybackClock.tsx

@@ -76,7 +76,7 @@ export default class PlaybackClock extends React.PureComponent<IProps, IState> {
         }
         return <Clock
             seconds={seconds}
-            aria-live={this.state.playbackPhase === PlaybackState.Playing ? "off" : undefined}
+            role="timer"
         />;
     }
 }

src/components/views/audio_messages/RecordingPlayback.tsx

@@ -22,45 +22,68 @@ import AudioPlayerBase, { IProps as IAudioPlayerBaseProps } from "./AudioPlayerB
 import SeekBar from "./SeekBar";
 import PlaybackWaveform from "./PlaybackWaveform";
 
-interface IProps extends IAudioPlayerBaseProps {
+export enum PlaybackLayout {
+    /**
+     * Clock on the left side of a waveform, without seek bar.
+     */
+    Composer,
+
     /**
-     * When true, use a waveform instead of a seek bar
+     * Clock on the right side of a waveform, with an added seek bar.
      */
-    withWaveform?: boolean;
+    Timeline,
+}
+
+interface IProps extends IAudioPlayerBaseProps {
+    layout?: PlaybackLayout; // Defaults to Timeline layout
 }
 
 export default class RecordingPlayback extends AudioPlayerBase<IProps> {
     // This component is rendered in two ways: the composer and timeline. They have different
     // rendering properties (specifically the difference of a waveform or not).
 
-    private renderWaveformLook(): ReactNode {
+    private renderComposerLook(): ReactNode {
         return <>
             <PlaybackClock playback={this.props.playback} />
             <PlaybackWaveform playback={this.props.playback} />
         </>;
     }
 
-    private renderSeekableLook(): ReactNode {
+    private renderTimelineLook(): ReactNode {
         return <>
-            <SeekBar
-                playback={this.props.playback}
-                tabIndex={-1} // prevent tabbing into the bar
-                playbackPhase={this.state.playbackPhase}
-                ref={this.seekRef}
-            />
+            <div className="mx_RecordingPlayback_timelineLayoutMiddle">
+                <PlaybackWaveform playback={this.props.playback} />
+                <SeekBar
+                    playback={this.props.playback}
+                    tabIndex={0} // allow keyboard users to fall into the seek bar
+                    playbackPhase={this.state.playbackPhase}
+                    ref={this.seekRef}
+                />
+            </div>
             <PlaybackClock playback={this.props.playback} />
         </>;
     }
 
     protected renderComponent(): ReactNode {
+        let body: ReactNode;
+        switch (this.props.layout) {
+            case PlaybackLayout.Composer:
+                body = this.renderComposerLook();
+                break;
+            case PlaybackLayout.Timeline: // default is timeline, fall through.
+            default:
+                body = this.renderTimelineLook();
+                break;
+        }
+
         return (
             <div className="mx_MediaBody mx_VoiceMessagePrimaryContainer" onKeyDown={this.onKeyDown}>
                 <PlayPauseButton
                     playback={this.props.playback}
                     playbackPhase={this.state.playbackPhase}
                     ref={this.playPauseRef}
                 />
-                { this.props.withWaveform ? this.renderWaveformLook() : this.renderSeekableLook() }
+                { body }
             </div>
         );
     }

src/components/views/rooms/VoiceRecordComposerTile.tsx

@@ -28,7 +28,7 @@ import LiveRecordingWaveform from "../audio_messages/LiveRecordingWaveform";
 import LiveRecordingClock from "../audio_messages/LiveRecordingClock";
 import { VoiceRecordingStore } from "../../../stores/VoiceRecordingStore";
 import { UPDATE_EVENT } from "../../../stores/AsyncStore";
-import RecordingPlayback from "../audio_messages/RecordingPlayback";
+import RecordingPlayback, { PlaybackLayout } from "../audio_messages/RecordingPlayback";
 import Modal from "../../../Modal";
 import ErrorDialog from "../dialogs/ErrorDialog";
 import MediaDeviceHandler, { MediaDeviceKindEnum } from "../../../MediaDeviceHandler";
@@ -231,7 +231,10 @@ export default class VoiceRecordComposerTile extends React.PureComponent<IProps,
         if (!this.state.recorder) return null; // no recorder means we're not recording: no waveform
 
         if (this.state.recordingPhase !== RecordingState.Started) {
-            return <RecordingPlayback playback={this.state.recorder.getPlayback()} withWaveform={true} />;
+            return <RecordingPlayback
+                playback={this.state.recorder.getPlayback()}
+                layout={PlaybackLayout.Composer}
+            />;
         }
 
         // only other UI is the recording-in-progress UI

test/components/views/audio_messages/RecordingPlayback-test.tsx

@@ -20,13 +20,14 @@ import { mocked } from 'jest-mock';
 import { logger } from 'matrix-js-sdk/src/logger';
 import { act } from 'react-dom/test-utils';
 
-import RecordingPlayback from '../../../../src/components/views/audio_messages/RecordingPlayback';
+import RecordingPlayback, { PlaybackLayout } from '../../../../src/components/views/audio_messages/RecordingPlayback';
 import { Playback } from '../../../../src/audio/Playback';
 import RoomContext, { TimelineRenderingType } from '../../../../src/contexts/RoomContext';
 import { createAudioContext } from '../../../../src/audio/compat';
 import { findByTestId, flushPromises } from '../../../test-utils';
 import PlaybackWaveform from '../../../../src/components/views/audio_messages/PlaybackWaveform';
 import SeekBar from "../../../../src/components/views/audio_messages/SeekBar";
+import PlaybackClock from "../../../../src/components/views/audio_messages/PlaybackClock";
 
 jest.mock('../../../../src/audio/compat', () => ({
     createAudioContext: jest.fn(),
@@ -128,19 +129,34 @@ describe('<RecordingPlayback />', () => {
         expect(playback.toggle).toHaveBeenCalled();
     });
 
-    it('should render a seek bar by default', () => {
-        const playback = new Playback(new ArrayBuffer(8));
-        const component = getComponent({ playback });
+    describe('Composer Layout', () => {
+        it('should have a waveform, no seek bar, and clock', () => {
+            const playback = new Playback(new ArrayBuffer(8));
+            const component = getComponent({ playback, layout: PlaybackLayout.Composer });
 
-        expect(component.find(PlaybackWaveform).length).toBeFalsy();
-        expect(component.find(SeekBar).length).toBeTruthy();
+            expect(component.find(PlaybackClock).length).toBeTruthy();
+            expect(component.find(PlaybackWaveform).length).toBeTruthy();
+            expect(component.find(SeekBar).length).toBeFalsy();
+        });
     });
 
-    it('should render a waveform when requested', () => {
-        const playback = new Playback(new ArrayBuffer(8));
-        const component = getComponent({ playback, withWaveform: true });
+    describe('Timeline Layout', () => {
+        it('should have a waveform, a seek bar, and clock', () => {
+            const playback = new Playback(new ArrayBuffer(8));
+            const component = getComponent({ playback, layout: PlaybackLayout.Timeline });
 
-        expect(component.find(PlaybackWaveform).length).toBeTruthy();
-        expect(component.find(SeekBar).length).toBeFalsy();
+            expect(component.find(PlaybackClock).length).toBeTruthy();
+            expect(component.find(PlaybackWaveform).length).toBeTruthy();
+            expect(component.find(SeekBar).length).toBeTruthy();
+        });
+
+        it('should be the default', () => {
+            const playback = new Playback(new ArrayBuffer(8));
+            const component = getComponent({ playback }); // no layout set for test
+
+            expect(component.find(PlaybackClock).length).toBeTruthy();
+            expect(component.find(PlaybackWaveform).length).toBeTruthy();
+            expect(component.find(SeekBar).length).toBeTruthy();
+        });
     });
 });