Whoops

* Basic grid setup

* Fixing thumb on two-up

* Adding margin so you can still access the two-up

* Allow multi-panel to keep one open only

* Edge cases for one-open

* Abstracting results so it can be used as a heading.

* Ordering of items in mobile view. Changing scrolling element.

* Adding labels to collapsed view

* Adding height animation to multi-panel

* Fixing animation bugs

* Expand/collapse icon

* Allow two-up and pinch-zoom to work beneath controls

* Range bubble now behaves properly on mobile

* No longer need this.

* Prevent options overflow at larger widths

src/components/Options/index.tsx

@@ -1,7 +1,7 @@
 import { h, Component } from 'preact';
 
 import * as style from './style.scss';
-import { bind, Fileish } from '../../lib/initial-util';
+import { bind } from '../../lib/initial-util';
 import { cleanSet, cleanMerge } from '../../lib/clean-modify';
 import OptiPNGEncoderOptions from '../../codecs/optipng/options';
 import MozJpegEncoderOptions from '../../codecs/mozjpeg/options';
@@ -35,13 +35,10 @@ import {
 import { QuantizeOptions } from '../../codecs/imagequant/processor-meta';
 import { ResizeOptions } from '../../codecs/resize/processor-meta';
 import { PreprocessorState } from '../../codecs/preprocessors';
-import FileSize from './FileSize';
-import { DownloadIcon } from '../../lib/icons';
 import { SourceImage } from '../App';
 import Checkbox from '../checkbox';
 import Expander from '../expander';
 import Select from '../select';
-import '../custom-els/LoadingSpinner';
 
 const encoderOptionsComponentMap = {
   [identity.type]: undefined,
@@ -60,55 +57,29 @@ const encoderOptionsComponentMap = {
 };
 
 interface Props {
-  orientation: 'horizontal' | 'vertical';
-  loading: boolean;
+  mobileView: boolean;
   source?: SourceImage;
-  imageIndex: number;
-  imageFile?: Fileish;
-  downloadUrl?: string;
   encoderState: EncoderState;
   preprocessorState: PreprocessorState;
   onEncoderTypeChange(newType: EncoderType): void;
   onEncoderOptionsChange(newOptions: EncoderOptions): void;
   onPreprocessorOptionsChange(newOptions: PreprocessorState): void;
-  onCopyToOtherClick(): void;
 }
 
 interface State {
   encoderSupportMap?: EncoderSupportMap;
-  showLoadingState: boolean;
 }
 
-const loadingReactionDelay = 500;
-
 export default class Options extends Component<Props, State> {
   state: State = {
     encoderSupportMap: undefined,
-    showLoadingState: false,
   };
 
-  /** The timeout ID between entering the loading state, and changing UI */
-  private loadingTimeoutId: number = 0;
-
   constructor() {
     super();
     encodersSupported.then(encoderSupportMap => this.setState({ encoderSupportMap }));
   }
 
-  componentDidUpdate(prevProps: Props, prevState: State) {
-    if (prevProps.loading && !this.props.loading) {
-      // Just stopped loading
-      clearTimeout(this.loadingTimeoutId);
-      this.setState({ showLoadingState: false });
-    } else if (!prevProps.loading && this.props.loading) {
-      // Just started loading
-      this.loadingTimeoutId = self.setTimeout(
-        () => this.setState({ showLoadingState: true }),
-        loadingReactionDelay,
-      );
-    }
-  }
-
   @bind
   onEncoderTypeChange(event: Event) {
     const el = event.currentTarget as HTMLSelectElement;
@@ -143,30 +114,20 @@ export default class Options extends Component<Props, State> {
     );
   }
 
-  @bind
-  onCopyToOtherClick(event: Event) {
-    event.preventDefault();
-    this.props.onCopyToOtherClick();
-  }
-
   render(
     {
       source,
-      imageIndex,
-      imageFile,
-      downloadUrl,
-      orientation,
       encoderState,
       preprocessorState,
       onEncoderOptionsChange,
     }: Props,
-    { encoderSupportMap, showLoadingState }: State,
+    { encoderSupportMap }: State,
   ) {
     // tslint:disable variable-name
     const EncoderOptionComponent = encoderOptionsComponentMap[encoderState.type];
 
     return (
-      <div class={style.options}>
+      <div class={style.optionsScroller}>
         <Expander>
           {encoderState.type === identity.type ? null :
             <div>
@@ -211,67 +172,30 @@ export default class Options extends Component<Props, State> {
 
         <h3 class={style.optionsTitle}>Compress</h3>
 
-        <div class={style.optionsScroller}>
-          <section class={`${style.optionOneCell} ${style.optionsSection}`}>
-            {encoderSupportMap ?
-              <Select value={encoderState.type} onChange={this.onEncoderTypeChange} large>
-                {encoders.filter(encoder => encoderSupportMap[encoder.type]).map(encoder => (
-                  <option value={encoder.type}>{encoder.label}</option>
-                ))}
-              </Select>
-              :
-              <Select large><option>Loading…</option></Select>
-            }
-          </section>
-
-          <Expander>
-            {EncoderOptionComponent ?
-              <EncoderOptionComponent
-                options={
-                  // Casting options, as encoderOptionsComponentMap[encodeData.type] ensures
-                  // the correct type, but typescript isn't smart enough.
-                  encoderState.options as any
-                }
-                onChange={onEncoderOptionsChange}
-              />
-            : null}
-          </Expander>
-        </div>
-
-        <div class={style.optionsCopy}>
-          <button onClick={this.onCopyToOtherClick} class={style.copyButton}>
-            {imageIndex === 1 && '← '}
-            Copy settings across
-            {imageIndex === 0 && ' →'}
-          </button>
-        </div>
-
-        <div class={style.results}>
-          <div class={style.resultData}>
-            {!imageFile || showLoadingState ? 'Working…' :
-              <FileSize
-                blob={imageFile}
-                compareTo={(source && imageFile !== source.file) ? source.file : undefined}
-              />
-            }
-          </div>
-
-          <div class={style.download}>
-            {(downloadUrl && imageFile) && (
-              <a
-                class={`${style.downloadLink} ${showLoadingState ? style.downloadLinkDisable : ''}`}
-                href={downloadUrl}
-                download={imageFile.name}
-                title="Download"
-              >
-                <DownloadIcon class={style.downloadIcon} />
-              </a>
-            )}
-            {showLoadingState && <loading-spinner class={style.spinner} />}
-          </div>
-
-        </div>
+        <section class={`${style.optionOneCell} ${style.optionsSection}`}>
+          {encoderSupportMap ?
+            <Select value={encoderState.type} onChange={this.onEncoderTypeChange} large>
+              {encoders.filter(encoder => encoderSupportMap[encoder.type]).map(encoder => (
+                <option value={encoder.type}>{encoder.label}</option>
+              ))}
+            </Select>
+            :
+            <Select large><option>Loading…</option></Select>
+          }
+        </section>
 
+        <Expander>
+          {EncoderOptionComponent ?
+            <EncoderOptionComponent
+              options={
+                // Casting options, as encoderOptionsComponentMap[encodeData.type] ensures
+                // the correct type, but typescript isn't smart enough.
+                encoderState.options as any
+              }
+              onChange={onEncoderOptionsChange}
+            />
+          : null}
+        </Expander>
       </div>
     );
   }

src/components/Options/style.scss

@@ -1,15 +1,5 @@
 $horizontalPadding: 15px;
 
-.options {
-  color: #fff;
-  width: 300px;
-  opacity: 0.9;
-  font-size: 1.2rem;
-  max-height: 100%;
-  display: flex;
-  flex-flow: column;
-}
-
 .options-title {
   background: rgba(0, 0, 0, 0.9);
   margin: 0;
@@ -65,102 +55,3 @@ $horizontalPadding: 15px;
   overflow-x: hidden;
   overflow-y: auto;
 }
-
-.results {
-  display: grid;
-  grid-template-columns: 1fr auto;
-  background: rgba(0, 0, 0, 0.9);
-  font-size: 1.4rem;
-}
-
-.result-data {
-  display: flex;
-  align-items: center;
-  padding: 0 $horizontalPadding;
-}
-
-.size-delta {
-  font-size: 1.1rem;
-  font-style: italic;
-  position: relative;
-  top: -1px;
-  margin-left: 0.3em;
-}
-
-.size-increase {
-  color: #e35050;
-}
-
-.size-decrease {
-  color: #50e3c2;
-}
-
-.options-copy {
-  display: grid;
-  background: rgba(0, 0, 0, 0.9);
-  padding: 5px;
-}
-
-.copy-button {
-  composes: unbutton from '../../lib/util.scss';
-  background: #484848;
-  border-radius: 4px;
-  color: #fff;
-  text-align: left;
-  padding: 5px 10px;
-}
-
-@keyframes action-enter {
-  from {
-    transform: rotate(-90deg);
-    opacity: 0;
-    animation-timing-function: ease-out;
-  }
-}
-
-@keyframes action-leave {
-  from {
-    transform: rotate(0deg);
-    opacity: 1;
-    animation-timing-function: ease-out;
-  }
-}
-
-.download {
-  background: #34B9EB;
-  --size: 38px;
-  width: var(--size);
-  height: var(--size);
-  display: grid;
-  align-items: center;
-  justify-items: center;
-}
-
-.download-link {
-  animation: action-enter 0.2s;
-  grid-area: 1/1;
-}
-
-.download-link-disable {
-  pointer-events: none;
-  opacity: 0;
-  transform: rotate(90deg);
-  animation: action-leave 0.2s;
-}
-
-.download-icon {
-  color: #fff;
-  display: block;
-  --size: 24px;
-  width: var(--size);
-  height: var(--size);
-  padding: 7px;
-  filter: drop-shadow(0 1px 0 rgba(0, 0, 0, 0.7));
-}
-
-.spinner {
-  --color: #fff;
-  --delay: 0;
-  --size: 22px;
-  grid-area: 1/1;
-}

src/components/Output/custom-els/TwoUp/styles.css

@@ -56,7 +56,7 @@ two-up[legacy-clip-compat] > :not(.two-up-handle) {
   box-shadow: 0 1px 4px rgba(0,0,0,0.1);
   color: var(--thumb-color);
   box-sizing: border-box;
-  padding: 0 48%;
+  padding: 0 calc(var(--thumb-size) * 0.24);
 }
 
 .scrubber svg {

src/components/Output/index.tsx

@@ -10,7 +10,7 @@ import { twoUpHandle } from './custom-els/TwoUp/styles.css';
 
 interface Props {
   originalImage?: ImageData;
-  orientation: 'horizontal' | 'vertical';
+  mobileView: boolean;
   leftCompressed?: ImageData;
   rightCompressed?: ImageData;
   leftImgContain: boolean;
@@ -180,10 +180,7 @@ export default class Output extends Component<Props, State> {
   }
 
   render(
-    {
-      orientation, leftCompressed, rightCompressed, leftImgContain, rightImgContain,
-      originalImage,
-    }: Props,
+    { mobileView, leftImgContain, rightImgContain, originalImage }: Props,
     { scale, editingScale, altBackground }: State,
   ) {
     const leftDraw = this.leftDrawable();
@@ -194,7 +191,7 @@ export default class Output extends Component<Props, State> {
         <two-up
           legacy-clip-compat
           class={style.twoUp}
-          orientation={orientation}
+          orientation={mobileView ? 'vertical' : 'horizontal'}
           // Event redirecting. See onRetargetableEvent.
           onTouchStartCapture={this.onRetargetableEvent}
           onTouchEndCapture={this.onRetargetableEvent}

src/components/Output/style.scss

@@ -1,7 +1,3 @@
-/*
-Note: These styles are temporary. They will be replaced before going live.
-*/
-
 .output {
   composes: abs-fill from '../../lib/util.scss';
 
@@ -47,6 +43,12 @@ Note: These styles are temporary. They will be replaced before going live.
   flex-wrap: wrap;
   contain: content;
 
+  // Allow clicks to fall through to the pinch zoom area
+  pointer-events: none;
+  & > * {
+    pointer-events: auto;
+  }
+
   @media (min-width: 860px) {
     top: auto;
     left: 320px;

src/components/compress/custom-els/MultiPanel/index.ts

@@ -1,19 +1,75 @@
-import './styles.css';
+import * as style from './styles.css';
+import { transitionHeight } from '../../../../lib/util';
 
-function getClosestHeading(el: Element) {
-  const closestEl = el.closest('multi-panel > *');
-  if (closestEl && closestEl.classList.contains('panel-heading')) {
-    return closestEl;
+interface CloseAllOptions {
+  exceptFirst?: boolean;
+}
+
+const openOneOnlyAttr = 'open-one-only';
+
+function getClosestHeading(el: Element): HTMLElement | undefined {
+  // Look for the child of multi-panel, but stop at interactive elements like links & buttons
+  const closestEl = el.closest('multi-panel > *, a, button');
+  if (closestEl && closestEl.classList.contains(style.panelHeading)) {
+    return closestEl as HTMLElement;
   }
   return undefined;
 }
 
+async function close(heading: HTMLElement) {
+  const content = heading.nextElementSibling as HTMLElement;
+
+  // if there is no content, nothing to expand
+  if (!content) return;
+
+  const from = content.getBoundingClientRect().height;
+
+  heading.removeAttribute('content-expanded');
+  content.setAttribute('aria-expanded', 'false');
+
+  // Wait a microtask so other calls to open/close can get the final sizes.
+  await null;
+
+  await transitionHeight(content, {
+    from,
+    to: 0,
+    duration: 300,
+  });
+
+  content.style.height = '';
+}
+
+async function open(heading: HTMLElement) {
+  const content = heading.nextElementSibling as HTMLElement;
+
+  // if there is no content, nothing to expand
+  if (!content) return;
+
+  const from = content.getBoundingClientRect().height;
+
+  heading.setAttribute('content-expanded', '');
+  content.setAttribute('aria-expanded', 'true');
+
+  const to = content.getBoundingClientRect().height;
+
+  // Wait a microtask so other calls to open/close can get the final sizes.
+  await null;
+
+  await transitionHeight(content, {
+    from, to,
+    duration: 300,
+  });
+
+  content.style.height = '';
+}
+
 /**
  * A multi-panel view that the user can add any number of 'panels'.
  * 'a panel' consists of two elements. Even index element becomes heading,
  * and odd index element becomes the expandable content.
  */
 export default class MultiPanel extends HTMLElement {
+  static get observedAttributes() { return [openOneOnlyAttr]; }
 
   constructor() {
     super();
@@ -31,12 +87,18 @@ export default class MultiPanel extends HTMLElement {
     this._childrenChange();
   }
 
+  attributeChangedCallback(name: string, oldValue: string | null, newValue: string | null) {
+    if (name === openOneOnlyAttr && newValue === null) {
+      this._closeAll({ exceptFirst: true });
+    }
+  }
+
   // Click event handler
   private _onClick(event: MouseEvent) {
-    const el = event.target as Element;
+    const el = event.target as HTMLElement;
     const heading = getClosestHeading(el);
     if (!heading) return;
-    this._expand(heading);
+    this._toggle(heading);
   }
 
   // KeyDown event handler
@@ -53,7 +115,8 @@ export default class MultiPanel extends HTMLElement {
     // don’t handle modifier shortcuts used by assistive technology.
     if (event.altKey) return;
 
-    let newHeading:HTMLElement | undefined;
+    let newHeading: HTMLElement | undefined;
+
     switch (event.key) {
       case 'ArrowLeft':
       case 'ArrowUp':
@@ -77,7 +140,7 @@ export default class MultiPanel extends HTMLElement {
       case 'Enter':
       case ' ':
       case 'Spacebar':
-        this._expand(heading);
+        this._toggle(heading);
         break;
 
       // Any other key press is ignored and passed back to the browser.
@@ -93,26 +156,32 @@ export default class MultiPanel extends HTMLElement {
     }
   }
 
-  private _expand(heading: Element) {
+  private _toggle(heading: HTMLElement) {
     if (!heading) return;
-    const content = heading.nextElementSibling;
-
-    // if there is no content, nothing to expand
-    if (!content) return;
 
     // toggle expanded and aria-expanded attributes
-    if (content.hasAttribute('expanded')) {
-      content.removeAttribute('expanded');
-      content.setAttribute('aria-expanded', 'false');
+    if (heading.hasAttribute('content-expanded')) {
+      close(heading);
     } else {
-      content.setAttribute('expanded', '');
-      content.setAttribute('aria-expanded', 'true');
+      if (this.openOneOnly) this._closeAll();
+      open(heading);
     }
   }
 
+  private _closeAll(options: CloseAllOptions = {}): void {
+    const { exceptFirst = false } = options;
+    let els = [...this.children].filter(el => el.matches('[content-expanded]')) as HTMLElement[];
+
+    if (exceptFirst) {
+      els = els.slice(1);
+    }
+
+    for (const el of els) close(el);
+  }
+
   // children of multi-panel should always be even number (heading/content pair)
   private _childrenChange() {
-    let preserveTabIndex : boolean = false;
+    let preserveTabIndex = false;
     let heading = this.firstElementChild;
 
     while (heading) {
@@ -123,31 +192,23 @@ export default class MultiPanel extends HTMLElement {
       // it means it has odd number of elements. log error and set heading to end the loop.
       if (!content) {
         console.error('<multi-panel> requires an even number of element children.');
-        heading = null;
-        continue;
+        break;
       }
 
       // When odd number of elements were inserted in the middle,
       // what was heading before may become content after the insertion.
       // Remove classes and attributes to prepare for this change.
-      heading.classList.remove('panel-content');
-
-      if (content.classList.contains('panel-heading')) {
-        content.classList.remove('panel-heading');
-      }
-      if (heading.hasAttribute('expanded') && heading.hasAttribute('aria-expanded')) {
-        heading.removeAttribute('expanded');
-        heading.removeAttribute('aria-expanded');
-      }
+      heading.classList.remove(style.panelContent);
+      content.classList.remove(style.panelHeading);
+      heading.removeAttribute('aria-expanded');
+      heading.removeAttribute('content-expanded');
 
       // If appreciable, remove tabindex from content which used to be header.
-      if (content.hasAttribute('tabindex')) {
-        content.removeAttribute('tabindex');
-      }
+      content.removeAttribute('tabindex');
 
       // Assign heading and content classes
-      heading.classList.add('panel-heading');
-      content.classList.add('panel-content');
+      heading.classList.add(style.panelHeading);
+      content.classList.add(style.panelContent);
 
       // Assign ids and aria-X for heading/content pair.
       heading.id = `panel-heading-${randomId}`;
@@ -163,6 +224,13 @@ export default class MultiPanel extends HTMLElement {
         heading.setAttribute('tabindex', '-1');
       }
 
+      // It's possible that the heading & content expanded attributes are now out of sync. Resync
+      // them using the heading as the source of truth.
+      content.setAttribute(
+        'aria-expanded',
+        heading.hasAttribute('content-expanded') ? 'true' : 'false',
+      );
+
       // next sibling of content = next heading
       heading = content.nextElementSibling;
     }
@@ -171,6 +239,9 @@ export default class MultiPanel extends HTMLElement {
     if (!preserveTabIndex && this.firstElementChild) {
       this.firstElementChild.setAttribute('tabindex', '0');
     }
+
+    // In case we're openOneOnly, and an additional open item has been added:
+    if (this.openOneOnly) this._closeAll({ exceptFirst: true });
   }
 
   // returns heading that is before currently selected one.
@@ -208,7 +279,7 @@ export default class MultiPanel extends HTMLElement {
   private _lastHeading() {
     // if the last element is heading, return last element
     const lastEl = this.lastElementChild as HTMLElement;
-    if (lastEl && lastEl.classList.contains('panel-heading')) {
+    if (lastEl && lastEl.classList.contains(style.panelHeading)) {
       return lastEl;
     }
     // otherwise return 2nd from the last
@@ -217,6 +288,21 @@ export default class MultiPanel extends HTMLElement {
       return lastContent.previousElementSibling as HTMLElement;
     }
   }
+
+  /**
+   * If true, only one panel can be open at once. When one opens, others close.
+   */
+  get openOneOnly() {
+    return this.hasAttribute(openOneOnlyAttr);
+  }
+
+  set openOneOnly(val: boolean) {
+    if (val) {
+      this.setAttribute(openOneOnlyAttr, '');
+    } else {
+      this.removeAttribute(openOneOnlyAttr);
+    }
+  }
 }
 
 customElements.define('multi-panel', MultiPanel);

src/components/compress/custom-els/MultiPanel/missing-types.d.ts

@@ -0,0 +1,9 @@
+interface MultiPanelAttributes extends JSX.HTMLAttributes {
+  'open-one-only'?: boolean;
+}
+
+declare namespace JSX {
+  interface IntrinsicElements {
+    'multi-panel': MultiPanelAttributes;
+  }
+}

src/components/compress/custom-els/MultiPanel/styles.css

@@ -0,0 +1,10 @@
+.panel-heading {
+  background: gray;
+}
+.panel-content {
+  height: 0px;
+  overflow: auto;
+}
+.panel-content[aria-expanded=true] {
+  height: auto;
+}

src/components/compress/index.tsx

@@ -24,18 +24,17 @@ import {
     EncoderOptions,
     encoderMap,
 } from '../../codecs/encoders';
-
 import {
   PreprocessorState,
   defaultPreprocessorState,
 } from '../../codecs/preprocessors';
-
 import { decodeImage } from '../../codecs/decoders';
 import { cleanMerge, cleanSet } from '../../lib/clean-modify';
 import Processor from '../../codecs/processor';
 import { VectorResizeOptions, BitmapResizeOptions } from '../../codecs/resize/processor-meta';
-
-type Orientation = 'horizontal' | 'vertical';
+import './custom-els/MultiPanel';
+import Results from '../results';
+import { ExpandIcon, CopyAcrossIconProps } from '../../lib/icons';
 
 export interface SourceImage {
   file: File | Fileish;
@@ -69,7 +68,7 @@ interface State {
   loading: boolean;
   loadingCounter: number;
   error?: string;
-  orientation: Orientation;
+  mobileView: boolean;
 }
 
 interface UpdateImageOptions {
@@ -137,7 +136,7 @@ async function processSvg(blob: Blob): Promise<HTMLImageElement> {
   const parser = new DOMParser();
   const text = await blobToText(blob);
   const document = parser.parseFromString(text, 'image/svg+xml');
-  const svg = document.documentElement;
+  const svg = document.documentElement!;
 
   if (svg.hasAttribute('width') && svg.hasAttribute('height')) {
     return blobToImg(blob);
@@ -155,8 +154,14 @@ async function processSvg(blob: Blob): Promise<HTMLImageElement> {
   return blobToImg(new Blob([newSource], { type: 'image/svg+xml' }));
 }
 
+// These are only used in the mobile view
+const resultTitles = ['Top', 'Bottom'];
+// These are only used in the desktop view
+const buttonPositions =
+  ['download-left', 'download-right'] as ('download-left' | 'download-right')[];
+
 export default class Compress extends Component<Props, State> {
-  widthQuery = window.matchMedia('(min-width: 500px)');
+  widthQuery = window.matchMedia('(max-width: 599px)');
 
   state: State = {
     source: undefined,
@@ -178,7 +183,7 @@ export default class Compress extends Component<Props, State> {
         loading: false,
       },
     ],
-    orientation: this.widthQuery.matches ? 'horizontal' : 'vertical',
+    mobileView: this.widthQuery.matches,
   };
 
   private readonly encodeCache = new ResultCache();
@@ -193,7 +198,7 @@ export default class Compress extends Component<Props, State> {
 
   @bind
   private onMobileWidthChange() {
-    this.setState({ orientation: this.widthQuery.matches ? 'horizontal' : 'vertical' });
+    this.setState({ mobileView: this.widthQuery.matches });
   }
 
   private onEncoderTypeChange(index: 0 | 1, newType: EncoderType): void {
@@ -395,36 +400,73 @@ export default class Compress extends Component<Props, State> {
     this.setState({ images });
   }
 
-  render({ }: Props, { loading, images, source, orientation }: State) {
+  render({ }: Props, { loading, images, source, mobileView }: State) {
     const [leftImage, rightImage] = images;
     const [leftImageData, rightImageData] = images.map(i => i.data);
 
+    const options = images.map((image, index) => (
+      <Options
+        source={source}
+        mobileView={mobileView}
+        preprocessorState={image.preprocessorState}
+        encoderState={image.encoderState}
+        onEncoderTypeChange={this.onEncoderTypeChange.bind(this, index)}
+        onEncoderOptionsChange={this.onEncoderOptionsChange.bind(this, index)}
+        onPreprocessorOptionsChange={this.onPreprocessorOptionsChange.bind(this, index)}
+      />
+    ));
+
+    const copyDirections =
+      (mobileView ? ['down', 'up'] : ['right', 'left']) as CopyAcrossIconProps['copyDirection'][];
+
+    const results = images.map((image, index) => (
+      <Results
+        downloadUrl={image.downloadUrl}
+        imageFile={image.file}
+        source={source}
+        loading={loading || image.loading}
+        copyDirection={copyDirections[index]}
+        onCopyToOtherClick={this.onCopyToOtherClick.bind(this, index)}
+        buttonPosition={mobileView ? 'stack-right' : buttonPositions[index]}
+      >
+        {!mobileView ? null : [
+          <ExpandIcon class={style.expandIcon} key="expand-icon"/>,
+          `${resultTitles[index]} (${encoderMap[image.encoderState.type].label})`,
+        ]}
+      </Results>
+    ));
+
     return (
-      <div class={`${style.compress} ${style[orientation]}`}>
+      <div class={style.compress}>
         <Output
           originalImage={source && source.data}
-          orientation={orientation}
+          mobileView={mobileView}
           leftCompressed={leftImageData}
           rightCompressed={rightImageData}
           leftImgContain={leftImage.preprocessorState.resize.fitMethod === 'cover'}
           rightImgContain={rightImage.preprocessorState.resize.fitMethod === 'cover'}
         />
-        {images.map((image, index) => (
-          <Options
-            loading={loading || image.loading}
-            source={source}
-            orientation={orientation}
-            imageIndex={index}
-            imageFile={image.file}
-            downloadUrl={image.downloadUrl}
-            preprocessorState={image.preprocessorState}
-            encoderState={image.encoderState}
-            onEncoderTypeChange={this.onEncoderTypeChange.bind(this, index)}
-            onEncoderOptionsChange={this.onEncoderOptionsChange.bind(this, index)}
-            onPreprocessorOptionsChange={this.onPreprocessorOptionsChange.bind(this, index)}
-            onCopyToOtherClick={this.onCopyToOtherClick.bind(this, index)}
-          />
-        ))}
+        {mobileView
+          ? (
+            <div class={style.options}>
+              <multi-panel class={style.multiPanel} open-one-only>
+                {results[0]}
+                {options[0]}
+                {results[1]}
+                {options[1]}
+              </multi-panel>
+            </div>
+          ) : ([
+            <div class={style.options} key="options0">
+              {options[0]}
+              {results[0]}
+            </div>,
+            <div class={style.options} key="options1">
+              {options[1]}
+              {results[1]}
+            </div>,
+          ])
+        }
       </div>
     );
   }

src/components/compress/style.scss

@@ -3,20 +3,72 @@
   height: 100%;
   contain: strict;
   display: grid;
+  align-items: end;
+  align-content: end;
+  grid-template-rows: 1fr auto;
 
-  &.horizontal {
+  @media (min-width: 600px) {
     grid-template-columns: 1fr auto;
-    grid-template-rows: calc(100% - 75px);
-
-    @media (min-width: 860px) {
-      grid-template-rows: 100%;
-    }
-    align-items: end;
-    align-content: end;
-  }
-
-  &.vertical {
-    // TODO: make the mobile view work
-    background: red;
+    grid-template-rows: 100%;
   }
 }
+
+.options {
+  color: #fff;
+  opacity: 0.9;
+  font-size: 1.2rem;
+  display: flex;
+  flex-flow: column;
+  max-width: 400px;
+  margin: 0 auto;
+  width: calc(100% - 60px);
+  max-height: calc(100% - 143px);
+  overflow: hidden;
+
+  @media (min-width: 600px) {
+    max-height: calc(100% - 75px);
+    width: 300px;
+    margin: 0;
+  }
+
+  @media (min-width: 860px) {
+    max-height: 100%;
+  }
+}
+
+.multi-panel {
+  position: relative;
+  display: flex;
+  flex-flow: column;
+
+  // Reorder so headings appear after content:
+  & > :nth-child(1) {
+    order: 2;
+    margin-bottom: 10px;
+  }
+
+  & > :nth-child(2) {
+    order: 1;
+  }
+
+  & > :nth-child(3) {
+    order: 4;
+  }
+
+  & > :nth-child(4) {
+    order: 3;
+  }
+}
+
+.expand-icon {
+  transform: rotate(180deg);
+  margin-left: -12px;
+}
+
+[content-expanded] .expand-icon {
+  transform: none;
+}
+
+:focus .expand-icon {
+  fill: #34B9EB;
+}

src/components/expander/index.tsx

@@ -1,6 +1,6 @@
 import { h, Component, ComponentChild, ComponentChildren } from 'preact';
 import * as style from './style.scss';
-import { linkRef } from '../../lib/initial-util';
+import { transitionHeight } from '../../lib/util';
 
 interface Props {
   children: ComponentChildren;
@@ -13,7 +13,6 @@ export default class Expander extends Component<Props, State> {
   state: State = {
     outgoingChildren: [],
   };
-  private el?: HTMLDivElement;
   private lastElHeight: number = 0;
 
   componentWillReceiveProps(nextProps: Props) {
@@ -32,10 +31,10 @@ export default class Expander extends Component<Props, State> {
 
     // Only interested if going from empty to not-empty, or not-empty to empty.
     if ((children[0] && nextChildren[0]) || (!children[0] && !nextChildren[0])) return;
-    this.lastElHeight = this.el!.getBoundingClientRect().height;
+    this.lastElHeight = this.base!.getBoundingClientRect().height;
   }
 
-  componentDidUpdate(previousProps: Props) {
+  async componentDidUpdate(previousProps: Props) {
     const children = this.props.children as ComponentChild[];
     const previousChildren = previousProps.children as ComponentChild[];
 
@@ -43,37 +42,20 @@ export default class Expander extends Component<Props, State> {
     if ((children[0] && previousChildren[0]) || (!children[0] && !previousChildren[0])) return;
 
     // What height do we need to transition to?
-    this.el!.style.transition = 'none';
-    this.el!.style.height = '';
-    const newHeight = children[0] ? this.el!.getBoundingClientRect().height : 0;
+    this.base!.style.height = '';
+    this.base!.style.overflow = 'hidden';
+    const newHeight = children[0] ? this.base!.getBoundingClientRect().height : 0;
 
-    if (this.lastElHeight === newHeight) {
-      this.el!.style.transition = '';
-      return;
-    }
+    await transitionHeight(this.base!, {
+      duration: 300,
+      from: this.lastElHeight,
+      to: newHeight,
+    });
 
-    // Set the currently rendered height absolutely.
-    this.el!.style.height = this.lastElHeight + 'px';
-    this.el!.style.transition = '';
-    this.el!.style.overflow = 'hidden';
-    // Force a style calc so the browser picks up the start value.
-    getComputedStyle(this.el!).height;
-    // Animate to the new height.
-    this.el!.style.height = newHeight + 'px';
-
-    const listener = () => {
-      // Unset the height & overflow, so element changes do the right thing.
-      this.el!.style.height = '';
-      this.el!.style.overflow = '';
-      this.el!.removeEventListener('transitionend', listener);
-      this.el!.removeEventListener('transitioncancel', listener);
-      if (this.state.outgoingChildren[0]) {
-        this.setState({ outgoingChildren: [] });
-      }
-    };
-
-    this.el!.addEventListener('transitionend', listener);
-    this.el!.addEventListener('transitioncancel', listener);
+    // Unset the height & overflow, so element changes do the right thing.
+    this.base!.style.height = '';
+    this.base!.style.overflow = '';
+    if (this.state.outgoingChildren[0]) this.setState({ outgoingChildren: [] });
   }
 
   render(props: Props, { outgoingChildren }: State) {
@@ -81,10 +63,7 @@ export default class Expander extends Component<Props, State> {
     const childrenExiting = !children[0] && outgoingChildren[0];
 
     return (
-      <div
-        ref={linkRef(this, 'el')}
-        class={`${style.expander} ${childrenExiting ? style.childrenExiting : ''}`}
-      >
+      <div class={childrenExiting ? style.childrenExiting : ''}>
         {children[0] ? children : outgoingChildren}
       </div>
     );

src/components/expander/style.scss

@@ -1,7 +1,3 @@
-.expander {
-  transition: height 200ms ease-in-out;
-}
-
 .children-exiting {
   & > * {
     pointer-events: none;

src/components/output/custom-els/MultiPanel/styles.css

@@ -1,11 +0,0 @@
-multi-panel > .panel-heading {
-  background:gray;
-}
-multi-panel > .panel-content {
-  height:0px;
-  overflow:scroll;
-  transition: height 1s;
-}
-multi-panel > .panel-content[expanded] {
-  height:auto;
-}

src/components/results/index.tsx

@@ -0,0 +1,105 @@
+import { h, Component, ComponentChildren, ComponentChild } from 'preact';
+
+import * as style from './style.scss';
+import FileSize from './FileSize';
+import { DownloadIcon, CopyAcrossIcon, CopyAcrossIconProps } from '../../lib/icons';
+import '../custom-els/LoadingSpinner';
+import { SourceImage } from '../compress';
+import { Fileish, bind } from '../../lib/initial-util';
+
+interface Props {
+  loading: boolean;
+  source?: SourceImage;
+  imageFile?: Fileish;
+  downloadUrl?: string;
+  children: ComponentChildren;
+  copyDirection: CopyAcrossIconProps['copyDirection'];
+  buttonPosition: keyof typeof buttonPositionClass;
+  onCopyToOtherClick(): void;
+}
+
+interface State {
+  showLoadingState: boolean;
+}
+
+const buttonPositionClass = {
+  'stack-right': style.stackRight,
+  'download-right': style.downloadRight,
+  'download-left': style.downloadLeft,
+};
+
+const loadingReactionDelay = 500;
+
+export default class Results extends Component<Props, State> {
+  state: State = {
+    showLoadingState: false,
+  };
+
+  /** The timeout ID between entering the loading state, and changing UI */
+  private loadingTimeoutId: number = 0;
+
+  componentDidUpdate(prevProps: Props, prevState: State) {
+    if (prevProps.loading && !this.props.loading) {
+      // Just stopped loading
+      clearTimeout(this.loadingTimeoutId);
+      this.setState({ showLoadingState: false });
+    } else if (!prevProps.loading && this.props.loading) {
+      // Just started loading
+      this.loadingTimeoutId = self.setTimeout(
+        () => this.setState({ showLoadingState: true }),
+        loadingReactionDelay,
+      );
+    }
+  }
+
+  @bind
+  private onCopyToOtherClick(event: Event) {
+    event.preventDefault();
+    this.props.onCopyToOtherClick();
+  }
+
+  render(
+    { source, imageFile, downloadUrl, children, copyDirection, buttonPosition }: Props,
+    { showLoadingState }: State,
+  ) {
+
+    return (
+      <div class={`${style.results} ${buttonPositionClass[buttonPosition]}`}>
+        <div class={style.resultData}>
+          {(children as ComponentChild[])[0]
+            ? <div class={style.resultTitle}>{children}</div>
+            : null
+          }
+          {!imageFile || showLoadingState ? 'Working…' :
+            <FileSize
+              blob={imageFile}
+              compareTo={(source && imageFile !== source.file) ? source.file : undefined}
+            />
+          }
+        </div>
+
+        <button
+          class={style.copyToOther}
+          title="Copy settings to other side"
+          onClick={this.onCopyToOtherClick}
+        >
+          <CopyAcrossIcon class={style.copyIcon} copyDirection={copyDirection} />
+        </button>
+
+        <div class={style.download}>
+          {(downloadUrl && imageFile) && (
+            <a
+              class={`${style.downloadLink} ${showLoadingState ? style.downloadLinkDisable : ''}`}
+              href={downloadUrl}
+              download={imageFile.name}
+              title="Download"
+            >
+              <DownloadIcon class={style.downloadIcon} />
+            </a>
+          )}
+          {showLoadingState && <loading-spinner class={style.spinner} />}
+        </div>
+      </div>
+    );
+  }
+}

src/components/results/style.scss

@@ -0,0 +1,131 @@
+@keyframes action-enter {
+  from {
+    transform: rotate(-90deg);
+    opacity: 0;
+    animation-timing-function: ease-out;
+  }
+}
+
+@keyframes action-leave {
+  from {
+    transform: rotate(0deg);
+    opacity: 1;
+    animation-timing-function: ease-out;
+  }
+}
+
+.results {
+  display: grid;
+  grid-template-columns: [text] 1fr [copy-button] auto [download-button] auto;
+  background: rgba(0, 0, 0, 0.9);
+  font-size: 1rem;
+
+  @media (min-width: 400px) {
+    font-size: 1.2rem;
+  }
+
+  @media (min-width: 600px) {
+    font-size: 1.4rem;
+  }
+
+  &:focus {
+    outline: none;
+  }
+}
+
+.result-data {
+  grid-row: 1;
+  grid-column: text;
+  display: flex;
+  align-items: center;
+  padding: 0 10px;
+  white-space: nowrap;
+  overflow: hidden;
+}
+
+.download-right {
+  grid-template-columns: [copy-button] auto [text] 1fr [download-button] auto;
+}
+
+.download-left {
+  grid-template-columns: [download-button] auto [text] 1fr [copy-button] auto;
+}
+
+.stack-right {
+  & .result-data {
+    padding: 0 15px;
+  }
+}
+
+.result-title {
+  display: flex;
+  align-items: center;
+  margin-right: 0.4em;
+}
+
+.size-delta {
+  font-size: 0.8em;
+  font-style: italic;
+  position: relative;
+  top: -1px;
+  margin-left: 0.3em;
+}
+
+.size-increase {
+  color: #e35050;
+}
+
+.size-decrease {
+  color: #50e3c2;
+}
+
+.download {
+  grid-row: 1;
+  grid-column: download-button;
+  background: #34B9EB;
+  --size: 38px;
+  width: var(--size);
+  height: var(--size);
+  display: grid;
+  align-items: center;
+  justify-items: center;
+}
+
+.download-link {
+  animation: action-enter 0.2s;
+  grid-area: 1/1;
+}
+
+.download-link-disable {
+  pointer-events: none;
+  opacity: 0;
+  transform: rotate(90deg);
+  animation: action-leave 0.2s;
+}
+
+.download-icon,
+.copy-icon {
+  color: #fff;
+  display: block;
+  --size: 24px;
+  width: var(--size);
+  height: var(--size);
+  padding: 7px;
+  filter: drop-shadow(0 1px 0 rgba(0, 0, 0, 0.7));
+}
+
+.spinner {
+  --color: #fff;
+  --delay: 0;
+  --size: 22px;
+  grid-area: 1/1;
+}
+
+.copy-to-other {
+  grid-row: 1;
+  grid-column: copy-button;
+  composes: unbutton from '../../lib/util.scss';
+  composes: download;
+
+  background: #656565;
+}

src/custom-els/RangeInput/index.ts

@@ -1,5 +1,6 @@
 import { bind } from '../../lib/initial-util';
 import * as style from './styles.css';
+import { PointerTracker } from '../../lib/PointerTracker';
 
 const RETARGETED_EVENTS = ['focus', 'blur'];
 const UPDATE_EVENTS = ['input', 'change'];
@@ -26,6 +27,17 @@ class RangeInputElement extends HTMLElement {
     this._input.type = 'range';
     this._input.className = style.input;
 
+    const tracker = new PointerTracker(this._input, {
+      start: (): boolean => {
+        if (tracker.currentPointers.length !== 0) return false;
+        this._input.classList.add(style.touchActive);
+        return true;
+      },
+      end: () => {
+        this._input.classList.remove(style.touchActive);
+      },
+    });
+
     for (const event of RETARGETED_EVENTS) {
       this._input.addEventListener(event, this._retargetEvent, true);
     }

src/custom-els/RangeInput/styles.css

@@ -84,11 +84,11 @@ range-input::before {
   overflow: hidden;
 }
 
-.input:active + .thumb-wrapper .value-display {
+.touch-active + .thumb-wrapper .value-display {
   opacity: 1;
   transform: scale(1);
 }
 
-.input:active + .thumb-wrapper .thumb {
+.touch-active + .thumb-wrapper .thumb {
   box-shadow: 0 1px 3px rgba(0,0,0,0.5);
 }

src/lib/icons.tsx

@@ -41,3 +41,34 @@ export const CheckedIcon = (props: JSX.HTMLAttributes) => (
     <path d="M21.3 0H2.7A2.7 2.7 0 0 0 0 2.7v18.6A2.7 2.7 0 0 0 2.7 24h18.6a2.7 2.7 0 0 0 2.7-2.7V2.7A2.7 2.7 0 0 0 21.3 0zm-12 18.7L2.7 12l1.8-1.9L9.3 15 19.5 4.8l1.8 1.9z"/>
   </Icon>
 );
+
+export const ExpandIcon = (props: JSX.HTMLAttributes) => (
+  <Icon {...props}>
+    <path d="M16.6 8.6L12 13.2 7.4 8.6 6 10l6 6 6-6z"/>
+  </Icon>
+);
+
+const copyAcrossRotations = {
+  up: 90, right: 180, down: -90, left: 0,
+};
+
+export interface CopyAcrossIconProps extends JSX.HTMLAttributes {
+  copyDirection: keyof typeof copyAcrossRotations;
+}
+
+export const CopyAcrossIcon = (props: CopyAcrossIconProps) => {
+  const { copyDirection, ...otherProps } = props;
+  const id = 'point-' + copyDirection;
+  const rotation = copyAcrossRotations[copyDirection];
+
+  return (
+    <Icon {...otherProps}>
+      <defs>
+        <clipPath id={id}>
+          <path d="M-12-12v24h24v-24zM4.5 2h-4v3l-5-5 5-5v3h4z" transform={`translate(12 13) rotate(${rotation})`}/>
+        </clipPath>
+      </defs>
+      <path clip-path={`url(#${id})`} d="M19 3h-4.2c-.4-1.2-1.5-2-2.8-2s-2.4.8-2.8 2H5a2 2 0 0 0-2 2v14c0 1.1.9 2 2 2h14a2 2 0 0 0 2-2V5a2 2 0 0 0-2-2zm-7 0a1 1 0 0 1 0 2c-.6 0-1-.4-1-1s.4-1 1-1z"/>
+    </Icon>
+  );
+};

src/lib/util.ts

@@ -258,3 +258,43 @@ export function konami(): Promise<void> {
     window.addEventListener('keydown', listener);
   });
 }
+
+interface TransitionOptions {
+  from?: number;
+  to?: number;
+  duration?: number;
+  easing?: string;
+}
+
+export async function transitionHeight(el: HTMLElement, opts: TransitionOptions): Promise<void> {
+  const {
+    from = el.getBoundingClientRect().height,
+    to = el.getBoundingClientRect().height,
+    duration = 1000,
+    easing = 'ease-in-out',
+  } = opts;
+
+  if (from === to || duration === 0) {
+    el.style.height = to + 'px';
+    return;
+  }
+
+  el.style.height = from + 'px';
+  // Force a style calc so the browser picks up the start value.
+  getComputedStyle(el).transform;
+  el.style.transition = `height ${duration}ms ${easing}`;
+  el.style.height = to + 'px';
+
+  return new Promise<void>((resolve) => {
+    const listener = (event: Event) => {
+      if (event.target !== el) return;
+      el.style.transition = '';
+      el.removeEventListener('transitionend', listener);
+      el.removeEventListener('transitioncancel', listener);
+      resolve();
+    };
+
+    el.addEventListener('transitionend', listener);
+    el.addEventListener('transitioncancel', listener);
+  });
+}