1// Copyright (c) 2012 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 ASH_WM_WINDOW_RESIZER_H_
6#define ASH_WM_WINDOW_RESIZER_H_
7
8#include "ash/ash_export.h"
9#include "ash/wm/drag_details.h"
10#include "ash/wm/window_state.h"
11#include "base/basictypes.h"
12#include "base/memory/scoped_ptr.h"
13#include "ui/gfx/rect.h"
14#include "ui/wm/public/window_move_client.h"
15
16namespace aura {
17class Window;
18}
19
20namespace ash {
21
22// WindowResizer is used by ToplevelWindowEventFilter to handle dragging, moving
23// or resizing a window. All coordinates passed to this are in the parent
24// windows coordinates.
25class ASH_EXPORT WindowResizer {
26 public:
27  // Constants to identify the type of resize.
28  static const int kBoundsChange_None;
29  static const int kBoundsChange_Repositions;
30  static const int kBoundsChange_Resizes;
31
32  // Used to indicate which direction the resize occurs in.
33  static const int kBoundsChangeDirection_None;
34  static const int kBoundsChangeDirection_Horizontal;
35  static const int kBoundsChangeDirection_Vertical;
36
37  WindowResizer();
38  WindowResizer(wm::WindowState* window_state);
39  virtual ~WindowResizer();
40
41  // Returns a bitmask of the kBoundsChange_ values.
42  static int GetBoundsChangeForWindowComponent(int component);
43
44  // Returns a bitmask of the kBoundsChange_ values.
45  static int GetPositionChangeDirectionForWindowComponent(int window_component);
46
47  // Invoked to drag/move/resize the window. |location| is in the coordinates
48  // of the window supplied to the constructor. |event_flags| is the event
49  // flags from the event.
50  virtual void Drag(const gfx::Point& location, int event_flags) = 0;
51
52  // Invoked to complete the drag.
53  virtual void CompleteDrag() = 0;
54
55  // Reverts the drag.
56  virtual void RevertDrag() = 0;
57
58  // Returns the target window the resizer was created for.
59  aura::Window* GetTarget() const {
60    return window_state_ ? window_state_->window() : NULL;
61  }
62
63  // See comment for |DragDetails::initial_location_in_parent|.
64  const gfx::Point& GetInitialLocation() const {
65    return window_state_->drag_details()->initial_location_in_parent;
66  }
67
68  // Drag parameters established when drag starts.
69  const DragDetails& details() const { return *window_state_->drag_details(); }
70
71 protected:
72  gfx::Rect CalculateBoundsForDrag(const gfx::Point& location);
73
74  static bool IsBottomEdge(int component);
75
76  // WindowState of the drag target.
77  wm::WindowState* window_state_;
78
79 private:
80  // In case of touch resizing, adjusts deltas so that the border is positioned
81  // just under the touch point.
82  void AdjustDeltaForTouchResize(int* delta_x, int* delta_y);
83
84  // Returns the new origin of the window. The arguments are the difference
85  // between the current location and the initial location.
86  gfx::Point GetOriginForDrag(int delta_x, int delta_y);
87
88  // Returns the size of the window for the drag.
89  gfx::Size GetSizeForDrag(int* delta_x, int* delta_y);
90
91  // Returns the width of the window.
92  int GetWidthForDrag(int min_width, int* delta_x);
93
94  // Returns the height of the drag.
95  int GetHeightForDrag(int min_height, int* delta_y);
96};
97
98// Creates a WindowResizer for |window|. This can return a scoped_ptr
99// initialized with NULL if |window| should not be resized nor dragged.
100ASH_EXPORT scoped_ptr<WindowResizer> CreateWindowResizer(
101    aura::Window* window,
102    const gfx::Point& point_in_parent,
103    int window_component,
104    aura::client::WindowMoveSource source);
105
106}  // namespace ash
107
108#endif  // ASH_WM_WINDOW_RESIZER_H_
109