Restructure click shield (#1611)

* Rename one-click-embedding to click shield
* Removes the static fallback image from the vimeo frame. The set URL is broken.
* Adds the ability to define background colors for the click shield background


Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

cypress/integration/linkEmbedder.spec.ts

@@ -14,7 +14,8 @@ describe('Link gets replaced with embedding: ', () => {
   it('GitHub Gist', () => {
     cy.setCodemirrorContent('https://gist.github.com/schacon/1')
     cy.getMarkdownBody()
-      .find('.one-click-embedding.gist-frame')
+      .find('[data-cypress-id="click-shield-gist"] .preview-background')
+      .parent()
       .click()
     cy.getMarkdownBody()
       .find('iframe[data-cypress-id=gh-gist]')
@@ -24,7 +25,7 @@ describe('Link gets replaced with embedding: ', () => {
   it('YouTube', () => {
     cy.setCodemirrorContent('https://www.youtube.com/watch?v=YE7VzlLtp-4')
     cy.getMarkdownBody()
-      .find('.one-click-embedding-preview')
+      .find('[data-cypress-id="click-shield-youtube"] .preview-background')
       .should('have.attr', 'src', 'https://i.ytimg.com/vi/YE7VzlLtp-4/maxresdefault.jpg')
       .parent()
       .click()
@@ -46,7 +47,7 @@ describe('Link gets replaced with embedding: ', () => {
     })
     cy.setCodemirrorContent('https://vimeo.com/23237102')
     cy.getMarkdownBody()
-      .find('.one-click-embedding-preview')
+      .find('[data-cypress-id="click-shield-vimeo"] .preview-background')
       .should('have.attr', 'src', 'https://i.vimeocdn.com/video/503631401_640.jpg')
       .parent()
       .click()
@@ -58,7 +59,7 @@ describe('Link gets replaced with embedding: ', () => {
   it('Asciinema', () => {
     cy.setCodemirrorContent('https://asciinema.org/a/117928')
     cy.getMarkdownBody()
-      .find('.one-click-embedding-preview')
+      .find('[data-cypress-id="click-shield-asciinema"] .preview-background')
       .should('have.attr', 'src', 'https://asciinema.org/a/117928.png')
       .parent()
       .click()

cypress/integration/shortcodes.spec.ts

@@ -37,10 +37,10 @@ describe('Short code gets replaced or rendered: ', () => {
   })
 
   describe('youtube', () => {
-    it('renders one-click-embedding', () => {
+    it('renders click-shield', () => {
       cy.setCodemirrorContent(`{%youtube YE7VzlLtp-4 %}`)
       cy.getMarkdownBody()
-        .find('.one-click-embedding.embed-responsive-item')
+        .find('[data-cypress-id="click-shield-youtube"]')
     })
   })
 })

locales/en.json

@@ -29,7 +29,7 @@
             "svg": "Save as SVG",
             "errorJson": "Error parsing the JSON"
         },
-        "one-click-embedding": {
+        "clickShield": {
           "previewHoverText": "Click to load content from {{target}}"
         }
     },

src/components/markdown-renderer/replace-components/asciinema/asciinema-frame.tsx

@@ -5,22 +5,29 @@
  */
 
 import React from 'react'
-import { OneClickEmbedding } from '../one-click-frame/one-click-embedding'
+import { ClickShield } from '../click-shield/click-shield'
 import type { IdProps } from '../custom-tag-with-id-component-replacer'
 
+/**
+ * Renders an embedding for https://asciinema.org
+ *
+ * @param id The id from the asciinema url
+ */
 export const AsciinemaFrame: React.FC<IdProps> = ({ id }) => {
   return (
-    <OneClickEmbedding
-      containerClassName={'embed-responsive embed-responsive-16by9'}
-      previewContainerClassName={'embed-responsive-item'}
+    <ClickShield
       hoverIcon={'play'}
       targetDescription={'asciinema'}
-      loadingImageUrl={`https://asciinema.org/a/${id}.png`}>
-      <iframe
-        className='embed-responsive-item'
-        title={`asciinema cast ${id}`}
-        src={`https://asciinema.org/a/${id}/embed?autoplay=1`}
-      />
-    </OneClickEmbedding>
+      fallbackPreviewImageUrl={`https://asciinema.org/a/${id}.png`}
+      fallbackBackgroundColor={'#d40000'}
+      data-cypress-id={'click-shield-asciinema'}>
+      <span className={'embed-responsive embed-responsive-16by9'}>
+        <iframe
+          className='embed-responsive-item'
+          title={`asciinema cast ${id}`}
+          src={`https://asciinema.org/a/${id}/embed?autoplay=1`}
+        />
+      </span>
+    </ClickShield>
   )
 }

src/components/markdown-renderer/replace-components/click-shield/click-shield.scss

@@ -4,33 +4,44 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-.one-click-embedding {
+.click-shield {
 
   position: relative;
   cursor: pointer;
   width: 100%;
   overflow: hidden;
 
-  .one-click-embedding-icon {
+  .preview-hover {
     display: inline;
     position: absolute;
     top: 50%;
     left: 50%;
     transform: translate(-50%, -50%);
     color: white;
-    opacity: 0.4;
+    opacity: 0.5;
     transition: opacity 0.2s;
     text-shadow: #000000 0 0 5px;
   }
 
-  &:hover > .one-click-embedding-icon {
-    opacity: 0.8;
-    text-shadow: #000000 0 0 10px;
+  .preview-hover-text {
+    opacity: 0;
   }
 
-  .one-click-embedding-preview {
+  &:hover {
+    .preview-hover-text {
+      opacity: 1;
+    }
+    .preview-hover {
+      opacity: 1;
+      text-shadow: #000000 0 0 5px, #000000 0 0 10px;
+    }
+  }
+
+  .preview-background {
     background: none;
     height: 100%;
-    object-fit: contain;
+    object-fit: cover;
+    min-height: 300px;
+    width: 100%;
   }
 }

src/components/markdown-renderer/replace-components/click-shield/click-shield.tsx

@@ -0,0 +1,120 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import React, { useCallback, useEffect, useMemo, useState } from 'react'
+import { Trans, useTranslation } from 'react-i18next'
+import type { IconName } from '../../../common/fork-awesome/types'
+import { ShowIf } from '../../../common/show-if/show-if'
+import './click-shield.scss'
+import { ProxyImageFrame } from '../image/proxy-image-frame'
+import { Logger } from '../../../../utils/logger'
+import type { Property } from 'csstype'
+import type { PropsWithDataCypressId } from '../../../../utils/cypress-attribute'
+import { cypressId } from '../../../../utils/cypress-attribute'
+import { ForkAwesomeIcon } from '../../../common/fork-awesome/fork-awesome-icon'
+
+const log = new Logger('OneClickEmbedding')
+
+interface ClickShieldProps extends PropsWithDataCypressId {
+  onImageFetch?: () => Promise<string>
+  fallbackPreviewImageUrl?: string
+  hoverIcon?: IconName
+  hoverTextI18nKey?: string
+  targetDescription?: string
+  containerClassName?: string
+  fallbackBackgroundColor?: Property.BackgroundColor
+}
+
+/**
+ * Prevents loading of the children elements until the user unlocks the content by e.g. clicking.
+ *
+ * @param containerClassName Additional CSS classes for the complete component
+ * @param onImageFetch A callback that is used to get an URL for the preview image
+ * @param fallbackPreviewImageUrl The URL for an image that should be shown. If onImageFetch is defined then this image will be shown until onImageFetch provides another URL.
+ * @param targetDescription The name of the target service
+ * @param hoverIcon The name of an icon that should be shown in the preview
+ * @param fallbackBackgroundColor A color that should be used if no background image was provided or could be loaded.
+ * @param children The children element that should be shielded.
+ */
+export const ClickShield: React.FC<ClickShieldProps> = ({
+  containerClassName,
+  onImageFetch,
+  fallbackPreviewImageUrl,
+  children,
+  targetDescription,
+  hoverIcon,
+  fallbackBackgroundColor,
+  ...props
+}) => {
+  const [showChildren, setShowChildren] = useState(false)
+  const [previewImageUrl, setPreviewImageUrl] = useState(fallbackPreviewImageUrl)
+  const { t } = useTranslation()
+
+  const doShowChildren = useCallback(() => {
+    setShowChildren(true)
+  }, [])
+
+  useEffect(() => {
+    if (!onImageFetch) {
+      return
+    }
+    onImageFetch()
+      .then((imageLink) => {
+        setPreviewImageUrl(imageLink)
+      })
+      .catch((message) => {
+        log.error(message)
+      })
+  }, [onImageFetch])
+
+  const fallbackBackgroundStyle = useMemo<React.CSSProperties>(
+    () =>
+      !fallbackBackgroundColor
+        ? {}
+        : {
+            backgroundColor: fallbackBackgroundColor
+          },
+    [fallbackBackgroundColor]
+  )
+
+  const previewHoverText = useMemo(() => {
+    return targetDescription ? t('renderer.clickShield.previewHoverText', { target: targetDescription }) : ''
+  }, [t, targetDescription])
+
+  const previewBackground = useMemo(() => {
+    return previewImageUrl === undefined ? (
+      <span className={'preview-background embed-responsive-item'} style={fallbackBackgroundStyle} />
+    ) : (
+      <ProxyImageFrame
+        className={'preview-background embed-responsive-item'}
+        style={fallbackBackgroundStyle}
+        src={previewImageUrl}
+        alt={previewHoverText}
+        title={previewHoverText}
+      />
+    )
+  }, [fallbackBackgroundStyle, previewHoverText, previewImageUrl])
+
+  return (
+    <span className={containerClassName} {...cypressId(props['data-cypress-id'])}>
+      <ShowIf condition={showChildren}>{children}</ShowIf>
+      <ShowIf condition={!showChildren}>
+        <span className={`click-shield embed-responsive embed-responsive-16by9`} onClick={doShowChildren}>
+          {previewBackground}
+          <ShowIf condition={!!hoverIcon}>
+            <span className={`preview-hover text-center`}>
+              <span className={'preview-hover-text'}>
+                <Trans i18nKey={'renderer.clickShield.previewHoverText'} tOptions={{ target: targetDescription }} />
+              </span>
+              <br />
+              <ForkAwesomeIcon icon={hoverIcon as IconName} size={'5x'} className={'mb-2'} />
+            </span>
+          </ShowIf>
+        </span>
+      </ShowIf>
+    </span>
+  )
+}

src/components/markdown-renderer/replace-components/gist/gist-frame.scss

@@ -4,12 +4,6 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-.gist-frame {
-  .one-click-embedding-preview {
-    filter: blur(3px);
-  }
-}
-
 .gist-resizer-row {
   display: flex;
   justify-content: center;

src/components/markdown-renderer/replace-components/gist/gist-frame.tsx

@@ -8,8 +8,7 @@ import React, { useCallback } from 'react'
 import { cypressId } from '../../../../utils/cypress-attribute'
 import './gist-frame.scss'
 import { useResizeGistFrame } from './use-resize-gist-frame'
-import { OneClickEmbedding } from '../one-click-frame/one-click-embedding'
-import preview from './gist-preview.png'
+import { ClickShield } from '../click-shield/click-shield'
 import type { IdProps } from '../custom-tag-with-id-component-replacer'
 
 /**
@@ -28,11 +27,11 @@ export const GistFrame: React.FC<IdProps> = ({ id }) => {
   )
 
   return (
-    <OneClickEmbedding
-      previewContainerClassName={'gist-frame'}
-      loadingImageUrl={preview}
+    <ClickShield
+      fallbackBackgroundColor={'#161b22'}
       hoverIcon={'github'}
-      targetDescription={'GitHub Gist'}>
+      targetDescription={'GitHub Gist'}
+      data-cypress-id={'click-shield-gist'}>
       <iframe
         sandbox=''
         {...cypressId('gh-gist')}
@@ -45,6 +44,6 @@ export const GistFrame: React.FC<IdProps> = ({ id }) => {
       <span className={'gist-resizer-row'}>
         <span className={'gist-resizer'} onMouseDown={onStart} onTouchStart={onStart} />
       </span>
-    </OneClickEmbedding>
+    </ClickShield>
   )
 }

src/components/markdown-renderer/replace-components/gist/gist-preview.png.license

@@ -1,3 +0,0 @@
-SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
-
-SPDX-License-Identifier: CC0-1.0

src/components/markdown-renderer/replace-components/one-click-frame/one-click-embedding.tsx

@@ -1,88 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-
-import React, { useEffect, useMemo, useState } from 'react'
-import { useTranslation } from 'react-i18next'
-import type { IconName } from '../../../common/fork-awesome/types'
-import { ShowIf } from '../../../common/show-if/show-if'
-import './one-click-embedding.scss'
-import { ProxyImageFrame } from '../image/proxy-image-frame'
-import { Logger } from '../../../../utils/logger'
-
-const log = new Logger('OneClickEmbedding')
-
-interface OneClickFrameProps {
-  onImageFetch?: () => Promise<string>
-  loadingImageUrl?: string
-  hoverIcon?: IconName
-  hoverTextI18nKey?: string
-  targetDescription?: string
-  containerClassName?: string
-  previewContainerClassName?: string
-  onActivate?: () => void
-}
-
-export const OneClickEmbedding: React.FC<OneClickFrameProps> = ({
-  previewContainerClassName,
-  containerClassName,
-  onImageFetch,
-  loadingImageUrl,
-  children,
-  targetDescription,
-  hoverIcon,
-  onActivate
-}) => {
-  const [showFrame, setShowFrame] = useState(false)
-  const [previewImageUrl, setPreviewImageUrl] = useState(loadingImageUrl)
-  const { t } = useTranslation()
-
-  const showChildren = () => {
-    setShowFrame(true)
-    if (onActivate) {
-      onActivate()
-    }
-  }
-
-  useEffect(() => {
-    if (!onImageFetch) {
-      return
-    }
-    onImageFetch()
-      .then((imageLink) => {
-        setPreviewImageUrl(imageLink)
-      })
-      .catch((message) => {
-        log.error(message)
-      })
-  }, [onImageFetch])
-
-  const previewHoverText = useMemo(() => {
-    return targetDescription ? t('renderer.one-click-embedding.previewHoverText', { target: targetDescription }) : ''
-  }, [t, targetDescription])
-
-  return (
-    <span className={containerClassName}>
-      <ShowIf condition={showFrame}>{children}</ShowIf>
-      <ShowIf condition={!showFrame}>
-        <span className={`one-click-embedding ${previewContainerClassName || ''}`} onClick={showChildren}>
-          <ShowIf condition={!!previewImageUrl}>
-            <ProxyImageFrame
-              className={'one-click-embedding-preview'}
-              src={previewImageUrl}
-              alt={previewHoverText}
-              title={previewHoverText}
-            />
-          </ShowIf>
-          <ShowIf condition={!!hoverIcon}>
-            <span className='one-click-embedding-icon text-center'>
-              <i className={`fa fa-${hoverIcon as string} fa-5x mb-2`} />
-            </span>
-          </ShowIf>
-        </span>
-      </ShowIf>
-    </span>
-  )
-}

src/components/markdown-renderer/replace-components/vimeo/vimeo-frame.tsx

@@ -5,7 +5,7 @@
  */
 
 import React, { useCallback } from 'react'
-import { OneClickEmbedding } from '../one-click-frame/one-click-embedding'
+import { ClickShield } from '../click-shield/click-shield'
 import type { IdProps } from '../custom-tag-with-id-component-replacer'
 
 interface VimeoApiResponse {
@@ -14,6 +14,11 @@ interface VimeoApiResponse {
   thumbnail_large?: string
 }
 
+/**
+ * Renders a video player embedding for https://vimeo.com
+ *
+ * @param id The id from the vimeo video url
+ */
 export const VimeoFrame: React.FC<IdProps> = ({ id }) => {
   const getPreviewImageLink = useCallback(async () => {
     const response = await fetch(`https://vimeo.com/api/v2/video/${id}.json`, {
@@ -33,19 +38,20 @@ export const VimeoFrame: React.FC<IdProps> = ({ id }) => {
   }, [id])
 
   return (
-    <OneClickEmbedding
-      containerClassName={'embed-responsive embed-responsive-16by9'}
-      previewContainerClassName={'embed-responsive-item'}
-      loadingImageUrl={'https://i.vimeocdn.com/video/'}
+    <ClickShield
       hoverIcon={'vimeo-square'}
       targetDescription={'Vimeo'}
-      onImageFetch={getPreviewImageLink}>
-      <iframe
-        className='embed-responsive-item'
-        title={`vimeo video of ${id}`}
-        src={`https://player.vimeo.com/video/${id}?autoplay=1`}
-        allow='accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture'
-      />
-    </OneClickEmbedding>
+      onImageFetch={getPreviewImageLink}
+      fallbackBackgroundColor={'#00adef'}
+      data-cypress-id={'click-shield-vimeo'}>
+      <span className={'embed-responsive embed-responsive-16by9'}>
+        <iframe
+          className='embed-responsive-item'
+          title={`vimeo video of ${id}`}
+          src={`https://player.vimeo.com/video/${id}?autoplay=1`}
+          allow='accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture'
+        />
+      </span>
+    </ClickShield>
   )
 }

src/components/markdown-renderer/replace-components/youtube/youtube-frame.tsx

@@ -5,23 +5,30 @@
  */
 
 import React from 'react'
-import { OneClickEmbedding } from '../one-click-frame/one-click-embedding'
+import { ClickShield } from '../click-shield/click-shield'
 import type { IdProps } from '../custom-tag-with-id-component-replacer'
 
+/**
+ * Renders a video player embedding for https://youtube.com
+ *
+ * @param id The id from the youtube video url
+ */
 export const YouTubeFrame: React.FC<IdProps> = ({ id }) => {
   return (
-    <OneClickEmbedding
-      containerClassName={'embed-responsive embed-responsive-16by9'}
-      previewContainerClassName={'embed-responsive-item'}
+    <ClickShield
       hoverIcon={'youtube-play'}
       targetDescription={'YouTube'}
-      loadingImageUrl={`https://i.ytimg.com/vi/${id}/maxresdefault.jpg`}>
-      <iframe
-        className='embed-responsive-item'
-        title={`youtube video of ${id}`}
-        src={`https://www.youtube-nocookie.com/embed/${id}?autoplay=1`}
-        allow='accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture'
-      />
-    </OneClickEmbedding>
+      fallbackPreviewImageUrl={`https://i.ytimg.com/vi/${id}/maxresdefault.jpg`}
+      fallbackBackgroundColor={'#ff0000'}
+      data-cypress-id={'click-shield-youtube'}>
+      <span className={'embed-responsive embed-responsive-16by9'}>
+        <iframe
+          className='embed-responsive-item'
+          title={`youtube video of ${id}`}
+          src={`https://www.youtube-nocookie.com/embed/${id}?autoplay=1`}
+          allow='accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture'
+        />
+      </span>
+    </ClickShield>
   )
 }