content/browser/renderer_host/input/synthetic_gesture_target_base.cc

// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/renderer_host/input/synthetic_gesture_target_base.h"

#include "content/browser/renderer_host/render_widget_host_impl.h"
#include "content/browser/renderer_host/render_widget_host_view_base.h"
#include "content/browser/renderer_host/ui_events_helper.h"
#include "content/common/input/input_event.h"
#include "content/common/input_messages.h"
#include "third_party/WebKit/public/web/WebInputEvent.h"
#include "ui/events/event.h"
#include "ui/events/latency_info.h"

using blink::WebInputEvent;
using blink::WebTouchEvent;
using blink::WebMouseEvent;
using blink::WebMouseWheelEvent;

namespace content {
namespace {

// This value was determined experimentally. It was sufficient to not cause a
// fling on Android.
const int kPointerAssumedStoppedTimeMs = 50;

// SyntheticGestureTargetBase passes input events straight on to the renderer
// without going through a gesture recognition framework. There is thus no touch
// slop.
const int kTouchSlopInDips = 0;

}  // namespace

SyntheticGestureTargetBase::SyntheticGestureTargetBase(
    RenderWidgetHostImpl* host)
    : host_(host) {
  DCHECK(host);
}

SyntheticGestureTargetBase::~SyntheticGestureTargetBase() {
}

void SyntheticGestureTargetBase::DispatchInputEventToPlatform(
    const InputEvent& event) {
  const WebInputEvent* web_event = event.web_event.get();
  if (WebInputEvent::isTouchEventType(web_event->type)) {
    DCHECK(SupportsSyntheticGestureSourceType(
            SyntheticGestureParams::TOUCH_INPUT));

    const WebTouchEvent* web_touch =
        static_cast<const WebTouchEvent*>(web_event);
    DispatchWebTouchEventToPlatform(*web_touch, event.latency_info);
  } else if (web_event->type == WebInputEvent::MouseWheel) {
    DCHECK(SupportsSyntheticGestureSourceType(
            SyntheticGestureParams::MOUSE_INPUT));

    const WebMouseWheelEvent* web_wheel =
        static_cast<const WebMouseWheelEvent*>(web_event);
    DispatchWebMouseWheelEventToPlatform(*web_wheel, event.latency_info);
  } else if (WebInputEvent::isMouseEventType(web_event->type)) {
    DCHECK(SupportsSyntheticGestureSourceType(
            SyntheticGestureParams::MOUSE_INPUT));

    const WebMouseEvent* web_mouse =
        static_cast<const WebMouseEvent*>(web_event);
    DispatchWebMouseEventToPlatform(*web_mouse, event.latency_info);
  } else {
    NOTREACHED();
  }
}

void SyntheticGestureTargetBase::DispatchWebTouchEventToPlatform(
      const blink::WebTouchEvent& web_touch,
      const ui::LatencyInfo& latency_info) {
  host_->ForwardTouchEventWithLatencyInfo(web_touch, latency_info);
}

void SyntheticGestureTargetBase::DispatchWebMouseWheelEventToPlatform(
      const blink::WebMouseWheelEvent& web_wheel,
      const ui::LatencyInfo& latency_info) {
  host_->ForwardWheelEventWithLatencyInfo(
      MouseWheelEventWithLatencyInfo(web_wheel, latency_info));
}

void SyntheticGestureTargetBase::DispatchWebMouseEventToPlatform(
      const blink::WebMouseEvent& web_mouse,
      const ui::LatencyInfo& latency_info) {
  host_->ForwardMouseEventWithLatencyInfo(
      MouseEventWithLatencyInfo(web_mouse, latency_info));
}

void SyntheticGestureTargetBase::OnSyntheticGestureCompleted(
    SyntheticGesture::Result result) {
  host_->Send(new InputMsg_SyntheticGestureCompleted(host_->GetRoutingID()));
}

void SyntheticGestureTargetBase::SetNeedsFlush() {
  host_->SetNeedsFlush();
}

SyntheticGestureParams::GestureSourceType
SyntheticGestureTargetBase::GetDefaultSyntheticGestureSourceType() const {
  return SyntheticGestureParams::MOUSE_INPUT;
}

bool SyntheticGestureTargetBase::SupportsSyntheticGestureSourceType(
    SyntheticGestureParams::GestureSourceType gesture_source_type) const {
  return gesture_source_type == SyntheticGestureParams::MOUSE_INPUT ||
      gesture_source_type == SyntheticGestureParams::TOUCH_INPUT;
}

base::TimeDelta SyntheticGestureTargetBase::PointerAssumedStoppedTime()
    const {
  return base::TimeDelta::FromMilliseconds(kPointerAssumedStoppedTimeMs);
}

int SyntheticGestureTargetBase::GetTouchSlopInDips() const {
  return kTouchSlopInDips;
}

}  // namespace content