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_LAUNCHER_LAUNCHER_MODEL_H_
6#define ASH_LAUNCHER_LAUNCHER_MODEL_H_
7
8#include "ash/ash_export.h"
9#include "ash/launcher/launcher_types.h"
10#include "base/basictypes.h"
11#include "base/observer_list.h"
12
13namespace ash {
14
15class LauncherModelObserver;
16
17// Model used by LauncherView.
18class ASH_EXPORT LauncherModel {
19 public:
20  enum Status {
21    STATUS_NORMAL,
22    // A status that indicates apps are syncing/loading.
23    STATUS_LOADING,
24  };
25
26  LauncherModel();
27  ~LauncherModel();
28
29  // Adds a new item to the model. Returns the resulting index.
30  int Add(const LauncherItem& item);
31
32  // Adds the item. |index| is the requested insertion index, which may be
33  // modified to meet type-based ordering. Returns the actual insertion index.
34  int AddAt(int index, const LauncherItem& item);
35
36  // Removes the item at |index|.
37  void RemoveItemAt(int index);
38
39  // Moves the item at |index| to |target_index|. |target_index| is in terms
40  // of the model *after* the item at |index| is removed.
41  void Move(int index, int target_index);
42
43  // Resets the item at the specified index. The item maintains its existing
44  // id and type.
45  void Set(int index, const LauncherItem& item);
46
47  // Returns the index of the item by id.
48  int ItemIndexByID(LauncherID id) const;
49
50  // Returns the index of the first panel or the index where the first panel
51  // would go if there are no panels.
52  int FirstPanelIndex() const;
53
54  // Returns the id assigned to the next item added.
55  LauncherID next_id() const { return next_id_; }
56
57  // Returns a reserved id which will not be used by the |LauncherModel|.
58  LauncherID reserve_external_id() { return next_id_++; }
59
60  // Returns an iterator into items() for the item with the specified id, or
61  // items().end() if there is no item with the specified id.
62  LauncherItems::const_iterator ItemByID(LauncherID id) const;
63
64  const LauncherItems& items() const { return items_; }
65  int item_count() const { return static_cast<int>(items_.size()); }
66
67  void SetStatus(Status status);
68  Status status() const { return status_; }
69
70  void AddObserver(LauncherModelObserver* observer);
71  void RemoveObserver(LauncherModelObserver* observer);
72
73 private:
74  // Makes sure |index| is in line with the type-based order of items. If that
75  // is not the case, adjusts index by shifting it to the valid range and
76  // returns the new value.
77  int ValidateInsertionIndex(LauncherItemType type, int index) const;
78
79  // ID assigned to the next item.
80  LauncherID next_id_;
81
82  LauncherItems items_;
83  Status status_;
84  ObserverList<LauncherModelObserver> observers_;
85
86  DISALLOW_COPY_AND_ASSIGN(LauncherModel);
87};
88
89}  // namespace ash
90
91#endif  // ASH_LAUNCHER_LAUNCHER_MODEL_H_
92