1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CONTENT_BROWSER_RENDERER_HOST_EVENT_WITH_LATENCY_INFO_H_
6#define CONTENT_BROWSER_RENDERER_HOST_EVENT_WITH_LATENCY_INFO_H_
7
8#include "ui/events/latency_info.h"
9
10#include "content/common/input/web_input_event_traits.h"
11
12namespace blink {
13class WebGestureEvent;
14class WebMouseEvent;
15class WebMouseWheelEvent;
16class WebTouchEvent;
17}
18
19namespace content {
20
21template <typename T>
22class EventWithLatencyInfo {
23 public:
24  T event;
25  ui::LatencyInfo latency;
26
27  EventWithLatencyInfo(const T& e, const ui::LatencyInfo& l)
28      : event(e), latency(l) {}
29
30  EventWithLatencyInfo() {}
31
32  bool CanCoalesceWith(const EventWithLatencyInfo& other)
33      const WARN_UNUSED_RESULT {
34    return WebInputEventTraits::CanCoalesce(other.event, event);
35  }
36
37  void CoalesceWith(const EventWithLatencyInfo& other) {
38    WebInputEventTraits::Coalesce(other.event, &event);
39    // When coalescing two input events, we keep the oldest LatencyInfo
40    // for Telemetry latency test since it will represent the longest
41    // latency.
42    if (other.latency.trace_id >= 0 &&
43        (latency.trace_id < 0 || other.latency.trace_id < latency.trace_id))
44      latency = other.latency;
45  }
46};
47
48typedef EventWithLatencyInfo<blink::WebGestureEvent>
49    GestureEventWithLatencyInfo;
50typedef EventWithLatencyInfo<blink::WebMouseWheelEvent>
51    MouseWheelEventWithLatencyInfo;
52typedef EventWithLatencyInfo<blink::WebMouseEvent>
53    MouseEventWithLatencyInfo;
54typedef EventWithLatencyInfo<blink::WebTouchEvent>
55    TouchEventWithLatencyInfo;
56
57}  // namespace content
58
59#endif  // CONTENT_BROWSER_RENDERER_HOST_EVENT_WITH_LATENCY_INFO_H_
60