[Glitch] Add expand/compress image button on image view box

Port 6a2db10f767879b9072b6c020ebadac4f985ed34 to glitch-soc

Signed-off-by: Thibaut Girka <thib@sitedethib.com>

3 files changed, 306 insertions, 21 deletions

diff --git a/app/javascript/flavours/glitch/features/ui/components/image_loader.js b/app/javascript/flavours/glitch/features/ui/components/image_loader.js
index 5e1cf75af..c6f16a792 100644
--- a/app/javascript/flavours/glitch/features/ui/components/image_loader.js
+++ b/app/javascript/flavours/glitch/features/ui/components/image_loader.js
@@ -13,6 +13,7 @@ export default class ImageLoader extends React.PureComponent {
     width: PropTypes.number,
     height: PropTypes.number,
     onClick: PropTypes.func,
+    zoomButtonHidden: PropTypes.bool,
   }
 
   static defaultProps = {
@@ -151,6 +152,9 @@ export default class ImageLoader extends React.PureComponent {
             alt={alt}
             src={src}
             onClick={onClick}
+            width={width}
+            height={height}
+            zoomButtonHidden={this.props.zoomButtonHidden}
           />
         )}
       </div>
diff --git a/app/javascript/flavours/glitch/features/ui/components/media_modal.js b/app/javascript/flavours/glitch/features/ui/components/media_modal.js
index aa6554107..e37df7208 100644
--- a/app/javascript/flavours/glitch/features/ui/components/media_modal.js
+++ b/app/javascript/flavours/glitch/features/ui/components/media_modal.js
@@ -35,23 +35,39 @@ class MediaModal extends ImmutablePureComponent {
   state = {
     index: null,
     navigationHidden: false,
+    zoomButtonHidden: false,
   };
 
   handleSwipe = (index) => {
     this.setState({ index: index % this.props.media.size });
   }
 
+  handleTransitionEnd = () => {
+    this.setState({
+      zoomButtonHidden: false,
+    });
+  }
+
   handleNextClick = () => {
-    this.setState({ index: (this.getIndex() + 1) % this.props.media.size });
+    this.setState({
+      index: (this.getIndex() + 1) % this.props.media.size,
+      zoomButtonHidden: true,
+    });
   }
 
   handlePrevClick = () => {
-    this.setState({ index: (this.props.media.size + this.getIndex() - 1) % this.props.media.size });
+    this.setState({
+      index: (this.props.media.size + this.getIndex() - 1) % this.props.media.size,
+      zoomButtonHidden: true,
+    });
   }
 
   handleChangeIndex = (e) => {
     const index = Number(e.currentTarget.getAttribute('data-index'));
-    this.setState({ index: index % this.props.media.size });
+    this.setState({
+      index: index % this.props.media.size,
+      zoomButtonHidden: true,
+    });
   }
 
   handleKeyDown = (e) => {
@@ -128,6 +144,7 @@ class MediaModal extends ImmutablePureComponent {
             alt={image.get('description')}
             key={image.get('url')}
             onClick={this.toggleNavigation}
+            zoomButtonHidden={this.state.zoomButtonHidden}
           />
         );
       } else if (image.get('type') === 'video') {
@@ -191,6 +208,7 @@ class MediaModal extends ImmutablePureComponent {
             style={swipeableViewsStyle}
             containerStyle={containerStyle}
             onChangeIndex={this.handleSwipe}
+            onTransitionEnd={this.handleTransitionEnd}
             index={index}
           >
             {content}
diff --git a/app/javascript/flavours/glitch/features/ui/components/zoomable_image.js b/app/javascript/flavours/glitch/features/ui/components/zoomable_image.js
index 3f6562bc9..004913480 100644
--- a/app/javascript/flavours/glitch/features/ui/components/zoomable_image.js
+++ b/app/javascript/flavours/glitch/features/ui/components/zoomable_image.js
@@ -1,8 +1,16 @@
 import React from 'react';
 import PropTypes from 'prop-types';
+import IconButton from 'flavours/glitch/components/icon_button';
+import { defineMessages, injectIntl } from 'react-intl';
+
+const messages = defineMessages({
+  compress: { id: 'lightbox.compress', defaultMessage: 'Compress image view box' },
+  expand: { id: 'lightbox.expand', defaultMessage: 'Expand image view box' },
+});
 
 const MIN_SCALE = 1;
 const MAX_SCALE = 4;
+const NAV_BAR_HEIGHT = 66;
 
 const getMidpoint = (p1, p2) => ({
   x: (p1.clientX + p2.clientX) / 2,
@@ -14,7 +22,77 @@ const getDistance = (p1, p2) =>
 
 const clamp = (min, max, value) => Math.min(max, Math.max(min, value));
 
-export default class ZoomableImage extends React.PureComponent {
+// Normalizing mousewheel speed across browsers
+// copy from: https://github.com/facebookarchive/fixed-data-table/blob/master/src/vendor_upstream/dom/normalizeWheel.js
+const normalizeWheel = event => {
+  // Reasonable defaults
+  const PIXEL_STEP = 10;
+  const LINE_HEIGHT = 40;
+  const PAGE_HEIGHT = 800;
+
+  let sX = 0,
+    sY = 0, // spinX, spinY
+    pX = 0,
+    pY = 0; // pixelX, pixelY
+
+  // Legacy
+  if ('detail' in event) {
+    sY = event.detail;
+  }
+  if ('wheelDelta' in event) {
+    sY = -event.wheelDelta / 120;
+  }
+  if ('wheelDeltaY' in event) {
+    sY = -event.wheelDeltaY / 120;
+  }
+  if ('wheelDeltaX' in event) {
+    sX = -event.wheelDeltaX / 120;
+  }
+
+  // side scrolling on FF with DOMMouseScroll
+  if ('axis' in event && event.axis === event.HORIZONTAL_AXIS) {
+    sX = sY;
+    sY = 0;
+  }
+
+  pX = sX * PIXEL_STEP;
+  pY = sY * PIXEL_STEP;
+
+  if ('deltaY' in event) {
+    pY = event.deltaY;
+  }
+  if ('deltaX' in event) {
+    pX = event.deltaX;
+  }
+
+  if ((pX || pY) && event.deltaMode) {
+    if (event.deltaMode === 1) { // delta in LINE units
+      pX *= LINE_HEIGHT;
+      pY *= LINE_HEIGHT;
+    } else { // delta in PAGE units
+      pX *= PAGE_HEIGHT;
+      pY *= PAGE_HEIGHT;
+    }
+  }
+
+  // Fall-back if spin cannot be determined
+  if (pX && !sX) {
+    sX = (pX < 1) ? -1 : 1;
+  }
+  if (pY && !sY) {
+    sY = (pY < 1) ? -1 : 1;
+  }
+
+  return {
+    spinX: sX,
+    spinY: sY,
+    pixelX: pX,
+    pixelY: pY,
+  };
+};
+
+export default @injectIntl
+class ZoomableImage extends React.PureComponent {
 
   static propTypes = {
     alt: PropTypes.string,
@@ -22,6 +100,8 @@ export default class ZoomableImage extends React.PureComponent {
     width: PropTypes.number,
     height: PropTypes.number,
     onClick: PropTypes.func,
+    zoomButtonHidden: PropTypes.bool,
+    intl: PropTypes.object.isRequired,
   }
 
   static defaultProps = {
@@ -32,6 +112,22 @@ export default class ZoomableImage extends React.PureComponent {
 
   state = {
     scale: MIN_SCALE,
+    zoomMatrix: {
+      type: null, // 'full-width' 'full-height'
+      rate: null, // full screen scale rate
+      clientWidth: null,
+      clientHeight: null,
+      offsetWidth: null,
+      offsetHeight: null,
+      clientHeightFixed: null,
+      scrollTop: null,
+      scrollLeft: null,
+    },
+    zoomState: 'expand', // 'expand' 'compress'
+    navigationHidden: false,
+    dragPosition: { top: 0, left: 0, x: 0, y: 0 },
+    dragged: false,
+    lockScroll: { x: 0, y: 0 },
   }
 
   removers = [];
@@ -49,17 +145,101 @@ export default class ZoomableImage extends React.PureComponent {
     // https://www.chromestatus.com/features/5093566007214080
     this.container.addEventListener('touchmove', handler, { passive: false });
     this.removers.push(() => this.container.removeEventListener('touchend', handler));
+
+    handler = this.mouseDownHandler;
+    this.container.addEventListener('mousedown', handler);
+    this.removers.push(() => this.container.removeEventListener('mousedown', handler));
+
+    handler = this.mouseWheelHandler;
+    this.container.addEventListener('wheel', handler);
+    this.removers.push(() => this.container.removeEventListener('wheel', handler));
+    // Old Chrome
+    this.container.addEventListener('mousewheel', handler);
+    this.removers.push(() => this.container.removeEventListener('mousewheel', handler));
+    // Old Firefox
+    this.container.addEventListener('DOMMouseScroll', handler);
+    this.removers.push(() => this.container.removeEventListener('DOMMouseScroll', handler));
+
+    this.initZoomMatrix();
   }
 
   componentWillUnmount () {
     this.removeEventListeners();
   }
 
+  componentDidUpdate () {
+    if (this.props.zoomButtonHidden) {
+      this.setState({ scale: MIN_SCALE }, () => {
+        this.container.scrollLeft = 0;
+        this.container.scrollTop = 0;
+      });
+    }
+
+    this.setState({ zoomState: this.state.scale >= this.state.zoomMatrix.rate ? 'compress' : 'expand' });
+
+    if (this.state.scale === 1) {
+      this.container.style.removeProperty('cursor');
+    }
+  }
+
   removeEventListeners () {
     this.removers.forEach(listeners => listeners());
     this.removers = [];
   }
 
+  mouseWheelHandler = e => {
+    e.preventDefault();
+
+    const event = normalizeWheel(e);
+
+    if (this.state.zoomMatrix.type === 'full-width') {
+      // full width, scroll vertical
+      this.container.scrollTop = this.container.scrollTop + event.pixelY;
+    } else {
+      // full height, scroll horizontal
+      this.container.scrollLeft = this.container.scrollLeft + event.pixelY;
+    }
+  }
+
+  mouseDownHandler = e => {
+    this.container.style.cursor = 'grabbing';
+    this.container.style.userSelect = 'none';
+
+    this.setState({ dragPosition: {
+      left: this.container.scrollLeft,
+      top: this.container.scrollTop,
+      // Get the current mouse position
+      x: e.clientX,
+      y: e.clientY,
+    } });
+
+    this.image.addEventListener('mousemove', this.mouseMoveHandler);
+    this.image.addEventListener('mouseup', this.mouseUpHandler);
+  }
+
+  mouseMoveHandler = e => {
+    const dx = e.clientX - this.state.dragPosition.x;
+    const dy = e.clientY - this.state.dragPosition.y;
+
+    if ((this.state.dragPosition.left - dx) >= this.state.lockScroll.x) {
+      this.container.scrollLeft = this.state.dragPosition.left - dx;
+    }
+
+    if ((this.state.dragPosition.top - dy) >= this.state.lockScroll.y) {
+      this.container.scrollTop = this.state.dragPosition.top - dy;
+    }
+
+    this.setState({ dragged: true });
+  }
+
+  mouseUpHandler = () => {
+    this.container.style.cursor = 'grab';
+    this.container.style.removeProperty('user-select');
+
+    this.image.removeEventListener('mousemove', this.mouseMoveHandler);
+    this.image.removeEventListener('mouseup', this.mouseUpHandler);
+  }
+
   handleTouchStart = e => {
     if (e.touches.length !== 2) return;
 
@@ -80,7 +260,8 @@ export default class ZoomableImage extends React.PureComponent {
 
     const distance = getDistance(...e.touches);
     const midpoint = getMidpoint(...e.touches);
-    const scale = clamp(MIN_SCALE, MAX_SCALE, this.state.scale * distance / this.lastDistance);
+    const _MAX_SCALE = Math.max(MAX_SCALE, this.state.zoomMatrix.rate);
+    const scale = clamp(MIN_SCALE, _MAX_SCALE, this.state.scale * distance / this.lastDistance);
 
     this.zoom(scale, midpoint);
 
@@ -110,8 +291,72 @@ export default class ZoomableImage extends React.PureComponent {
   handleClick = e => {
     // don't propagate event to MediaModal
     e.stopPropagation();
+    const dragged = this.state.dragged;
+    this.setState({ dragged: false });
+    if (dragged) return;
     const handler = this.props.onClick;
     if (handler) handler();
+    this.setState({ navigationHidden: !this.state.navigationHidden });
+  }
+
+  handleMouseDown = e => {
+    e.preventDefault();
+  }
+
+  initZoomMatrix = () => {
+    const { width, height } = this.props;
+    const { clientWidth, clientHeight } = this.container;
+    const { offsetWidth, offsetHeight } = this.image;
+    const clientHeightFixed = clientHeight - NAV_BAR_HEIGHT;
+
+    const type = width/height < clientWidth / clientHeightFixed ? 'full-width' : 'full-height';
+    const rate = type === 'full-width' ? clientWidth / offsetWidth : clientHeightFixed / offsetHeight;
+    const scrollTop = type === 'full-width' ?  (clientHeight - offsetHeight) / 2 - NAV_BAR_HEIGHT : (clientHeightFixed - offsetHeight) / 2;
+    const scrollLeft = (clientWidth - offsetWidth) / 2;
+
+    this.setState({
+      zoomMatrix: {
+        type: type,
+        rate: rate,
+        clientWidth: clientWidth,
+        clientHeight: clientHeight,
+        offsetWidth: offsetWidth,
+        offsetHeight: offsetHeight,
+        clientHeightFixed: clientHeightFixed,
+        scrollTop: scrollTop,
+        scrollLeft: scrollLeft,
+      },
+    });
+  }
+
+  handleZoomClick = e => {
+    e.preventDefault();
+    e.stopPropagation();
+
+    const { scale, zoomMatrix } = this.state;
+
+    if ( scale >= zoomMatrix.rate ) {
+      this.setState({ scale: MIN_SCALE }, () => {
+        this.container.scrollLeft = 0;
+        this.container.scrollTop = 0;
+        this.setState({ lockScroll: {
+          x: 0,
+          y: 0,
+        } });
+      });
+    } else {
+      this.setState({ scale: zoomMatrix.rate }, () => {
+        this.container.scrollLeft = zoomMatrix.scrollLeft;
+        this.container.scrollTop = zoomMatrix.scrollTop;
+        this.setState({ lockScroll: {
+          x: zoomMatrix.scrollLeft,
+          y: zoomMatrix.scrollTop,
+        } });
+      });
+    }
+
+    this.container.style.cursor = 'grab';
+    this.container.style.removeProperty('user-select');
   }
 
   setContainerRef = c => {
@@ -123,29 +368,47 @@ export default class ZoomableImage extends React.PureComponent {
   }
 
   render () {
-    const { alt, src } = this.props;
+    const { alt, src, width, height, intl } = this.props;
     const { scale } = this.state;
     const overflow = scale === 1 ? 'hidden' : 'scroll';
+    const zoomButtonSshouldHide = !this.state.navigationHidden && !this.props.zoomButtonHidden ? '' : 'media-modal__zoom-button--hidden';
+    const zoomButtonTitle = this.state.zoomState === 'compress' ? intl.formatMessage(messages.compress) : intl.formatMessage(messages.expand);
 
     return (
-      <div
-        className='zoomable-image'
-        ref={this.setContainerRef}
-        style={{ overflow }}
-      >
-        <img
-          role='presentation'
-          ref={this.setImageRef}
-          alt={alt}
-          title={alt}
-          src={src}
+      <React.Fragment>
+        <IconButton
+          className={`media-modal__zoom-button ${zoomButtonSshouldHide}`}
+          title={zoomButtonTitle}
+          icon={this.state.zoomState}
+          onClick={this.handleZoomClick}
+          size={40}
           style={{
-            transform: `scale(${scale})`,
-            transformOrigin: '0 0',
+            fontSize: '30px', /* Fontawesome's fa-compress fa-expand is larger than fa-close */
           }}
-          onClick={this.handleClick}
         />
-      </div>
+        <div
+          className='zoomable-image'
+          ref={this.setContainerRef}
+          style={{ overflow }}
+        >
+          <img
+            role='presentation'
+            ref={this.setImageRef}
+            alt={alt}
+            title={alt}
+            src={src}
+            width={width}
+            height={height}
+            style={{
+              transform: `scale(${scale})`,
+              transformOrigin: '0 0',
+            }}
+            draggable={false}
+            onClick={this.handleClick}
+            onMouseDown={this.handleMouseDown}
+          />
+        </div>
+      </React.Fragment>
     );
   }