1 files changed, 108 insertions, 0 deletions
diff --git a/devtools/client/inspector/animation/components/KeyframesProgressBar.js b/devtools/client/inspector/animation/components/KeyframesProgressBar.js
new file mode 100644
index 0000000000..b4e9e526de
--- /dev/null
+++ b/devtools/client/inspector/animation/components/KeyframesProgressBar.js
@@ -0,0 +1,108 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const {
+  createRef,
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const dom = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+class KeyframesProgressBar extends PureComponent {
+  static get propTypes() {
+    return {
+      addAnimationsCurrentTimeListener: PropTypes.func.isRequired,
+      animation: PropTypes.object.isRequired,
+      getAnimationsCurrentTime: PropTypes.func.isRequired,
+      removeAnimationsCurrentTimeListener: PropTypes.func.isRequired,
+      simulateAnimationForKeyframesProgressBar: PropTypes.func.isRequired,
+      timeScale: PropTypes.object.isRequired,
+    };
+  }
+
+  constructor(props) {
+    super(props);
+
+    this._progressBarRef = createRef();
+
+    this.onCurrentTimeUpdated = this.onCurrentTimeUpdated.bind(this);
+  }
+
+  componentDidMount() {
+    const { addAnimationsCurrentTimeListener } = this.props;
+
+    this.setupAnimation(this.props);
+    addAnimationsCurrentTimeListener(this.onCurrentTimeUpdated);
+  }
+
+  // FIXME: https://bugzilla.mozilla.org/show_bug.cgi?id=1774507
+  UNSAFE_componentWillReceiveProps(nextProps) {
+    const { animation, getAnimationsCurrentTime, timeScale } = nextProps;
+
+    this.setupAnimation(nextProps);
+    this.updateOffset(getAnimationsCurrentTime(), animation, timeScale);
+  }
+
+  componentWillUnmount() {
+    const { removeAnimationsCurrentTimeListener } = this.props;
+
+    removeAnimationsCurrentTimeListener(this.onCurrentTimeUpdated);
+    this.simulatedAnimation = null;
+  }
+
+  onCurrentTimeUpdated(currentTime) {
+    const { animation, timeScale } = this.props;
+    this.updateOffset(currentTime, animation, timeScale);
+  }
+
+  updateOffset(currentTime, animation, timeScale) {
+    const { createdTime, playbackRate } = animation.state;
+
+    const time =
+      (timeScale.minStartTime + currentTime - createdTime) * playbackRate;
+
+    if (isNaN(time)) {
+      // Setting an invalid currentTime will throw so bail out if time is not a number for
+      // any reason.
+      return;
+    }
+
+    this.simulatedAnimation.currentTime = time;
+    const position =
+      this.simulatedAnimation.effect.getComputedTiming().progress;
+
+    // onCurrentTimeUpdated is bound to requestAnimationFrame.
+    // As to update the component too frequently has performance issue if React controlled,
+    // update raw component directly. See Bug 1699039.
+    this._progressBarRef.current.style.marginInlineStart = `${position * 100}%`;
+  }
+
+  setupAnimation(props) {
+    const { animation, simulateAnimationForKeyframesProgressBar } = props;
+
+    if (this.simulatedAnimation) {
+      this.simulatedAnimation.cancel();
+    }
+
+    const timing = Object.assign({}, animation.state, {
+      iterations: animation.state.iterationCount || Infinity,
+    });
+
+    this.simulatedAnimation = simulateAnimationForKeyframesProgressBar(timing);
+  }
+
+  render() {
+    return dom.div(
+      { className: "keyframes-progress-bar-area" },
+      dom.div({
+        className: "indication-bar keyframes-progress-bar",
+        ref: this._progressBarRef,
+      })
+    );
+  }
+}
+
+module.exports = KeyframesProgressBar;