Image aspect ratio (#1665)

* Allow user to specify an aspect ratio for various images

* added a comment on what is supported

* fixed typo

* Fixed lint and test errors

.gitignore

@@ -21,6 +21,9 @@ lib
 bin
 dist
 
+# vscode
+.vscode
+
 # Secrets
 .lokalise_token
 yarn-error.log

src/common/util/parse-aspect-ratio.js

@@ -0,0 +1,24 @@
+export default function parseAspectRatio(input) {
+  // Handle 16x9, 16:9, 1.78x1, 1.78:1, 1.78
+  // Ignore everything else
+  function parseOrThrow(number) {
+    const parsed = parseFloat(number);
+    if (isNaN(parsed)) throw new Error(`${number} is not a number`);
+    return parsed;
+  }
+  try {
+    if (input) {
+      const arr = input.replace(':', 'x').split('x');
+      if (arr.length === 0) {
+        return null;
+      }
+
+      return arr.length === 1 ?
+        { w: parseOrThrow(arr[0]), h: 1 } :
+        { w: parseOrThrow(arr[0]), h: parseOrThrow(arr[1]) };
+    }
+  } catch (err) {
+    // Ignore the error
+  }
+  return null;
+}

src/panels/lovelace/cards/hui-picture-entity-card.js

@@ -58,6 +58,7 @@ class HuiPictureEntityCard extends EventsMixin(LocalizeMixin(PolymerElement)) {
           state-image="[[_config.state_image]]"
           camera-image="[[_getCameraImage(_config)]]"
           entity="[[_config.entity]]"
+          aspect-ratio="[[_config.aspect_ratio]]"
         ></hui-image>
         <template is="dom-if" if="[[_showNameAndState(_config)]]">
           <div class="footer both">

src/panels/lovelace/cards/hui-picture-glance-card.js

@@ -78,6 +78,7 @@ class HuiPictureGlanceCard extends NavigateMixin(LocalizeMixin(EventsMixin(Polym
           state-image="[[_config.state_image]]"
           camera-image="[[_config.camera_image]]"
           entity="[[_config.entity]]"
+          aspect-ratio="[[_config.aspect_ratio]]"
         ></hui-image>
         <div class="box">
           <template is="dom-if" if="[[_config.title]]">

src/panels/lovelace/components/hui-image.js

@@ -5,6 +5,8 @@ import '@polymer/paper-toggle-button/paper-toggle-button.js';
 import { STATES_OFF } from '../../../common/const.js';
 import LocalizeMixin from '../../../mixins/localize-mixin.js';
 
+import parseAspectRatio from '../../../common/util/parse-aspect-ratio.js';
+
 const UPDATE_INTERVAL = 10000;
 const DEFAULT_FILTER = 'grayscale(100%)';
 
@@ -13,8 +15,23 @@ const DEFAULT_FILTER = 'grayscale(100%)';
  */
 class HuiImage extends LocalizeMixin(PolymerElement) {
   static get template() {
+    return html`
+      ${this.styleTemplate}
+      <div id="wrapper">
+        <img
+          id="image"
+          src="[[_imageSrc]]"
+          on-error="_onImageError"
+          on-load="_onImageLoad" />
+        <div id="brokenImage"></div>
+      </div>
+    `;
+  }
+
+  static get styleTemplate() {
     return html`
       <style>
+
         img {
           display: block;
           height: auto;
@@ -30,19 +47,26 @@ class HuiImage extends LocalizeMixin(PolymerElement) {
           display: none;
         }
 
+        .ratio {
+          position: relative;
+          width: 100%;
+          height: 0
+        }
+
+        .ratio img, .ratio div {
+          position: absolute;
+          top: 0;
+          left: 0;
+          width: 100%;
+          height: 100%;
+        }
+
         #brokenImage {
           background: grey url('/static/images/image-broken.svg') center/36px no-repeat;
         }
 
       </style>
-
+    `;
-      <img
-        id="image"
-        src="[[_imageSrc]]"
-        on-error="_onImageError"
-        on-load="_onImageLoad" />
-      <div id="brokenImage"></div>
-`;
   }
 
   static get properties() {
@@ -55,6 +79,7 @@ class HuiImage extends LocalizeMixin(PolymerElement) {
       image: String,
       stateImage: Object,
       cameraImage: String,
+      aspectRatio: String,
       filter: String,
       stateFilter: Object,
       _imageSrc: String
@@ -62,7 +87,7 @@ class HuiImage extends LocalizeMixin(PolymerElement) {
   }
 
   static get observers() {
-    return ['_configChanged(image, stateImage, cameraImage)'];
+    return ['_configChanged(image, stateImage, cameraImage, aspectRatio)'];
   }
 
   connectedCallback() {
@@ -77,7 +102,14 @@ class HuiImage extends LocalizeMixin(PolymerElement) {
     clearInterval(this.timer);
   }
 
-  _configChanged(image, stateImage, cameraImage) {
+  _configChanged(image, stateImage, cameraImage, aspectRatio) {
+    const ratio = parseAspectRatio(aspectRatio);
+
+    if (ratio && ratio.w > 0 && ratio.h > 0) {
+      this.$.wrapper.style.paddingBottom = `${((100 * ratio.h) / ratio.w).toFixed(2)}%`;
+      this.$.wrapper.classList.add('ratio');
+    }
+
     if (cameraImage) {
       this._updateCameraImageSrc();
     } else if (image && !stateImage) {
@@ -88,15 +120,19 @@ class HuiImage extends LocalizeMixin(PolymerElement) {
   _onImageError() {
     this._imageSrc = null;
     this.$.image.classList.add('hidden');
+    if (!this.$.wrapper.classList.contains('ratio')) {
       this.$.brokenImage.style.setProperty('height', `${this._lastImageHeight || '100'}px`);
+    }
     this.$.brokenImage.classList.remove('hidden');
   }
 
   _onImageLoad() {
     this.$.image.classList.remove('hidden');
     this.$.brokenImage.classList.add('hidden');
+    if (!this.$.wrapper.classList.contains('ratio')) {
       this._lastImageHeight = this.$.image.offsetHeight;
     }
+  }
 
   _hassChanged(hass) {
     if (this.cameraImage || !this.entity) {

src/panels/lovelace/elements/hui-image-element.js

@@ -28,6 +28,7 @@ class HuiImageElement extends ElementClickMixin(PolymerElement) {
         filter="[[_config.filter]]"
         state-filter="[[_config.state_filter]]"
         title$="[[computeTooltip(hass, _config)]]"
+        aspect-ratio="[[_config.aspect_ratio]]"
       ></hui-image>
     `;
   }

test-mocha/common/util/parse_aspect_ratio_test.js

@@ -0,0 +1,53 @@
+import assert from 'assert';
+
+import parseAspectRatio from '../../../src/common/util/parse-aspect-ratio.js';
+
+describe('parseAspectRatio', () => {
+  const ratio16by9 = { w: 16, h: 9 };
+  const ratio178 = { w: 1.78, h: 1 };
+
+  it('Parses 16x9', () => {
+    const r = parseAspectRatio('16x9');
+    assert.deepEqual(r, ratio16by9);
+  });
+
+  it('Parses 16:9', () => {
+    const r = parseAspectRatio('16:9');
+    assert.deepEqual(r, ratio16by9);
+  });
+
+  it('Parses 1.78x1', () => {
+    const r = parseAspectRatio('1.78x1');
+    assert.deepEqual(r, ratio178);
+  });
+
+  it('Parses 1.78:1', () => {
+    const r = parseAspectRatio('1.78:1');
+    assert.deepEqual(r, ratio178);
+  });
+
+  it('Parses 1.78', () => {
+    const r = parseAspectRatio('1.78');
+    assert.deepEqual(r, ratio178);
+  });
+
+  it('Skips null states', () => {
+    const r = parseAspectRatio(null);
+    assert.equal(r, null);
+  });
+
+  it('Skips empty states', () => {
+    const r = parseAspectRatio('   ');
+    assert.equal(r, null);
+  });
+
+  it('Skips invalid input', () => {
+    const r = parseAspectRatio('mary had a little lamb');
+    assert.equal(r, null);
+  });
+
+  it('Skips invalid, but close input', () => {
+    const r = parseAspectRatio('mary:lamb');
+    assert.equal(r, null);
+  });
+});