1 files changed, 112 insertions, 0 deletions
diff --git a/javascript/videojs/src/js/tracks/html-track-element-list.js b/javascript/videojs/src/js/tracks/html-track-element-list.js
new file mode 100644
index 0000000..3c8107c
--- /dev/null
+++ b/javascript/videojs/src/js/tracks/html-track-element-list.js
@@ -0,0 +1,112 @@
+/**
+ * @file html-track-element-list.js
+ */
+
+/**
+ * The current list of {@link HtmlTrackElement}s.
+ */
+class HtmlTrackElementList {
+
+  /**
+   * Create an instance of this class.
+   *
+   * @param {HtmlTrackElement[]} [tracks=[]]
+   *        A list of `HtmlTrackElement` to instantiate the list with.
+   */
+  constructor(trackElements = []) {
+    this.trackElements_ = [];
+
+    /**
+     * @memberof HtmlTrackElementList
+     * @member {number} length
+     *         The current number of `Track`s in the this Trackist.
+     * @instance
+     */
+    Object.defineProperty(this, 'length', {
+      get() {
+        return this.trackElements_.length;
+      }
+    });
+
+    for (let i = 0, length = trackElements.length; i < length; i++) {
+      this.addTrackElement_(trackElements[i]);
+    }
+  }
+
+  /**
+   * Add an {@link HtmlTrackElement} to the `HtmlTrackElementList`
+   *
+   * @param {HtmlTrackElement} trackElement
+   *        The track element to add to the list.
+   *
+   * @private
+   */
+  addTrackElement_(trackElement) {
+    const index = this.trackElements_.length;
+
+    if (!('' + index in this)) {
+      Object.defineProperty(this, index, {
+        get() {
+          return this.trackElements_[index];
+        }
+      });
+    }
+
+    // Do not add duplicate elements
+    if (this.trackElements_.indexOf(trackElement) === -1) {
+      this.trackElements_.push(trackElement);
+    }
+  }
+
+  /**
+   * Get an {@link HtmlTrackElement} from the `HtmlTrackElementList` given an
+   * {@link TextTrack}.
+   *
+   * @param {TextTrack} track
+   *        The track associated with a track element.
+   *
+   * @return {HtmlTrackElement|undefined}
+   *         The track element that was found or undefined.
+   *
+   * @private
+   */
+  getTrackElementByTrack_(track) {
+    let trackElement_;
+
+    for (let i = 0, length = this.trackElements_.length; i < length; i++) {
+      if (track === this.trackElements_[i].track) {
+        trackElement_ = this.trackElements_[i];
+
+        break;
+      }
+    }
+
+    return trackElement_;
+  }
+
+  /**
+   * Remove a {@link HtmlTrackElement} from the `HtmlTrackElementList`
+   *
+   * @param {HtmlTrackElement} trackElement
+   *        The track element to remove from the list.
+   *
+   * @private
+   */
+  removeTrackElement_(trackElement) {
+    for (let i = 0, length = this.trackElements_.length; i < length; i++) {
+      if (trackElement === this.trackElements_[i]) {
+        if (this.trackElements_[i].track && typeof this.trackElements_[i].track.off === 'function') {
+          this.trackElements_[i].track.off();
+        }
+
+        if (typeof this.trackElements_[i].off === 'function') {
+          this.trackElements_[i].off();
+        }
+        this.trackElements_.splice(i, 1);
+        break;
+      }
+    }
+  }
+}
+
+export default HtmlTrackElementList;