content/browser/renderer_host/input/input_router.h

// 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.

#ifndef CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_H_
#define CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_H_

#include "base/basictypes.h"
#include "content/browser/renderer_host/event_with_latency_info.h"
#include "content/common/input/input_event_ack_state.h"
#include "content/public/browser/native_web_keyboard_event.h"
#include "ipc/ipc_listener.h"
#include "third_party/WebKit/public/web/WebInputEvent.h"

namespace content {

class InputRouterClient;

// The InputRouter allows the embedder to customize how input events are
// sent to the renderer, and how responses are dispatched to the browser.
// While the router should respect the relative order in which events are
// received, it is free to customize when those events are dispatched.
class InputRouter : public IPC::Listener {
 public:
  virtual ~InputRouter() {}

  // Should be called only in response to |SetNeedsFlush| requests made via
  // the |InputRouterClient|.
  virtual void Flush() = 0;

  // Send and take ownership of the the given InputMsg_*. This should be used
  // only for event types not associated with a WebInputEvent.  Returns true on
  // success and false otherwise.
  virtual bool SendInput(scoped_ptr<IPC::Message> message) = 0;

  // WebInputEvents
  virtual void SendMouseEvent(
      const MouseEventWithLatencyInfo& mouse_event) = 0;
  virtual void SendWheelEvent(
      const MouseWheelEventWithLatencyInfo& wheel_event) = 0;
  virtual void SendKeyboardEvent(
      const NativeWebKeyboardEvent& key_event,
      const ui::LatencyInfo& latency_info,
      bool is_shortcut) = 0;
  virtual void SendGestureEvent(
      const GestureEventWithLatencyInfo& gesture_event) = 0;
  virtual void SendTouchEvent(
      const TouchEventWithLatencyInfo& touch_event) = 0;

  // Returns the oldest queued or in-flight keyboard event sent to the router.
  virtual const NativeWebKeyboardEvent* GetLastKeyboardEvent() const = 0;

  // Returns |true| if the caller should immediately forward touch events to the
  // router.  When |false|, the caller can forego sending touch events, and
  // instead consume them directly.
  virtual bool ShouldForwardTouchEvent() const = 0;

  // Allow the router to make more informed input handling decisions based on
  // the current view.
  enum ViewFlags {
    VIEW_FLAGS_NONE   = 0,
    FIXED_PAGE_SCALE  = 1 << 0,
    MOBILE_VIEWPORT   = 1 << 1
  };
  virtual void OnViewUpdated(int view_flags) = 0;
};

}  // namespace content

#endif // CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_H_