Media Card: Add Marquee to Title (#5095)

* Marquee Addition

* Review Comments

* instance var name change

* fix merge

* Comments plus merge fix

src/panels/lovelace/cards/hui-media-control-card.ts

@@ -44,6 +44,7 @@ import {
 
 import "../../../components/ha-card";
 import "../../../components/ha-icon";
+import "../components/hui-marquee";
 
 function getContrastRatio(
   rgb1: [number, number, number],
@@ -88,6 +89,7 @@ export class HuiMediaControlCard extends LitElement implements LovelaceCard {
   @property() private _narrow: boolean = false;
   @property() private _veryNarrow: boolean = false;
   @property() private _cardHeight: number = 0;
+  @property() private _marqueeActive: boolean = false;
   private _progressInterval?: number;
   private _resizeObserver?: ResizeObserver;
 
@@ -240,8 +242,13 @@ export class HuiMediaControlCard extends LitElement implements LovelaceCard {
                     : html`
                         <div class="media-info">
                           <div class="title">
-                            ${stateObj.attributes.media_title ||
+                            <hui-marquee
+                              .text=${stateObj.attributes.media_title ||
                                 computeMediaDescription(stateObj)}
+                              .active=${this._marqueeActive}
+                              @mouseover=${this._marqueeMouseOver}
+                              @mouseleave=${this._marqueeMouseLeave}
+                            ></hui-marquee>
                           </div>
                           ${!stateObj.attributes.media_title
                             ? ""
@@ -564,6 +571,18 @@ export class HuiMediaControlCard extends LitElement implements LovelaceCard {
       });
   }
 
+  private _marqueeMouseOver(): void {
+    if (!this._marqueeActive) {
+      this._marqueeActive = true;
+    }
+  }
+
+  private _marqueeMouseLeave(): void {
+    if (this._marqueeActive) {
+      this._marqueeActive = false;
+    }
+  }
+
   static get styles(): CSSResult {
     return css`
       ha-card {

src/panels/lovelace/components/hui-marquee.ts

@@ -0,0 +1,89 @@
+import {
+  html,
+  LitElement,
+  PropertyValues,
+  TemplateResult,
+  customElement,
+  css,
+  CSSResult,
+  property,
+} from "lit-element";
+
+const marqueeSpeed = 0.2;
+
+@customElement("hui-marquee")
+class HuiMarquee extends LitElement {
+  @property() public text?: string;
+  @property() public active?: boolean;
+  private _interval?: number;
+  private _left: number = 0;
+
+  protected updated(changedProperties: PropertyValues): void {
+    super.updated(changedProperties);
+
+    if (
+      changedProperties.has("active") &&
+      this.active &&
+      !this._interval &&
+      this.offsetWidth < this.scrollWidth
+    ) {
+      this._interval = window.setInterval(() => {
+        this._play();
+      });
+
+      this.requestUpdate();
+    }
+  }
+
+  protected render(): TemplateResult {
+    if (!this.text) {
+      return html``;
+    }
+
+    return html`
+      <div>${this.text}</div>
+      ${this._interval
+        ? html`
+            <div>${this.text}</div>
+          `
+        : ""}
+    `;
+  }
+
+  private get _marqueeElementFirstChild(): HTMLElement {
+    return this.shadowRoot!.firstElementChild as HTMLElement;
+  }
+
+  private _play(): void {
+    this.style.marginLeft = "-" + this._left + "px";
+
+    if (!this.active && !this._left) {
+      clearInterval(this._interval);
+      this._interval = undefined;
+      return;
+    }
+
+    this._left += marqueeSpeed;
+    if (this._left >= this._marqueeElementFirstChild.offsetWidth + 16) {
+      this._left = 0;
+    }
+  }
+
+  static get styles(): CSSResult {
+    return css`
+      :host {
+        display: flex;
+      }
+
+      :host div {
+        margin-right: 16px;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "hui-marquee": HuiMarquee;
+  }
+}