// Copyright 2015 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 SERVICES_UI_WS_EVENT_DISPATCHER_DELEGATE_H_
#define SERVICES_UI_WS_EVENT_DISPATCHER_DELEGATE_H_

#include <stdint.h>

#include "services/ui/common/types.h"

namespace gfx {
class Point;
}

namespace ui {
class Event;
}

namespace ui {
namespace ws {

class Accelerator;
class ServerWindow;

// Used by EventDispatcher for mocking in tests.
class EventDispatcherDelegate {
 public:
  enum class AcceleratorPhase {
    PRE,
    POST,
  };

  virtual void OnAccelerator(uint32_t accelerator,
                             const ui::Event& event,
                             AcceleratorPhase phase) = 0;

  virtual void SetFocusedWindowFromEventDispatcher(ServerWindow* window) = 0;
  virtual ServerWindow* GetFocusedWindowForEventDispatcher() = 0;

  // Called when capture should be set on the native display. |window| is the
  // window capture is being set on.
  virtual void SetNativeCapture(ServerWindow* window) = 0;

  // Called when the native display is having capture released. There is no
  // longer a ServerWindow holding capture.
  virtual void ReleaseNativeCapture() = 0;

  // Called when EventDispatcher has a new value for the cursor and our
  // delegate should perform the native updates.
  virtual void UpdateNativeCursorFromDispatcher() = 0;

  // Called when |window| has lost capture. The native display may still be
  // holding capture. The delegate should not change native display capture.
  // ReleaseNativeCapture() is invoked if appropriate.
  virtual void OnCaptureChanged(ServerWindow* new_capture,
                                ServerWindow* old_capture) = 0;

  virtual void OnMouseCursorLocationChanged(const gfx::Point& point) = 0;

  // Dispatches an event to the specific client.
  virtual void DispatchInputEventToWindow(ServerWindow* target,
                                          ClientSpecificId client_id,
                                          const ui::Event& event,
                                          Accelerator* accelerator) = 0;

  // Returns the id of the client to send events to. |in_nonclient_area| is
  // true if the event occurred in the non-client area of the window.
  virtual ClientSpecificId GetEventTargetClientId(const ServerWindow* window,
                                                  bool in_nonclient_area) = 0;

  // Returns the window to start searching from at the specified location, or
  // null if there is a no window containing |location|. |location| should be in
  // screen coordinates and if a window is returned then |location| will be
  // updated to be relative to the origin of the window.
  virtual ServerWindow* GetRootWindowContaining(gfx::Point* location) = 0;

  // Called when event dispatch could not find a target. OnAccelerator may still
  // be called.
  virtual void OnEventTargetNotFound(const ui::Event& event) = 0;

 protected:
  virtual ~EventDispatcherDelegate() {}
};

}  // namespace ws
}  // namespace ui

#endif  // SERVICES_UI_WS_EVENT_DISPATCHER_DELEGATE_H_