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 CONTENT_BROWSER_HOST_ZOOM_MAP_IMPL_H_
6#define CONTENT_BROWSER_HOST_ZOOM_MAP_IMPL_H_
7
8#include <map>
9#include <string>
10#include <vector>
11
12#include "base/compiler_specific.h"
13#include "base/sequenced_task_runner_helpers.h"
14#include "base/supports_user_data.h"
15#include "base/synchronization/lock.h"
16#include "content/public/browser/host_zoom_map.h"
17#include "content/public/browser/notification_observer.h"
18#include "content/public/browser/notification_registrar.h"
19
20namespace content {
21
22class WebContentsImpl;
23
24// HostZoomMap needs to be deleted on the UI thread because it listens
25// to notifications on there (and holds a NotificationRegistrar).
26class CONTENT_EXPORT HostZoomMapImpl : public NON_EXPORTED_BASE(HostZoomMap),
27                                       public NotificationObserver,
28                                       public base::SupportsUserData::Data {
29 public:
30  HostZoomMapImpl();
31  virtual ~HostZoomMapImpl();
32
33  // HostZoomMap implementation:
34  virtual void CopyFrom(HostZoomMap* copy) OVERRIDE;
35  virtual double GetZoomLevelForHostAndScheme(
36      const std::string& scheme,
37      const std::string& host) const OVERRIDE;
38  // TODO(wjmaclean) Should we use a GURL here? crbug.com/384486
39  virtual bool HasZoomLevel(const std::string& scheme,
40                            const std::string& host) const OVERRIDE;
41  virtual ZoomLevelVector GetAllZoomLevels() const OVERRIDE;
42  virtual void SetZoomLevelForHost(
43      const std::string& host,
44      double level) OVERRIDE;
45  virtual void SetZoomLevelForHostAndScheme(
46      const std::string& scheme,
47      const std::string& host,
48      double level) OVERRIDE;
49  virtual bool UsesTemporaryZoomLevel(int render_process_id,
50                                      int render_view_id) const OVERRIDE;
51  virtual void SetTemporaryZoomLevel(int render_process_id,
52                                     int render_view_id,
53                                     double level) OVERRIDE;
54
55  virtual void ClearTemporaryZoomLevel(int render_process_id,
56                                       int render_view_id) OVERRIDE;
57  virtual double GetDefaultZoomLevel() const OVERRIDE;
58  virtual void SetDefaultZoomLevel(double level) OVERRIDE;
59  virtual scoped_ptr<Subscription> AddZoomLevelChangedCallback(
60      const ZoomLevelChangedCallback& callback) OVERRIDE;
61
62  // Returns the current zoom level for the specified WebContents. This may
63  // be a temporary zoom level, depending on UsesTemporaryZoomLevel().
64  double GetZoomLevelForWebContents(
65      const WebContentsImpl& web_contents_impl) const;
66
67  // Sets the zoom level for this WebContents. If this WebContents is using
68  // a temporary zoom level, then level is only applied to this WebContents.
69  // Otherwise, the level will be applied on a host level.
70  void SetZoomLevelForWebContents(const WebContentsImpl& web_contents_impl,
71                                  double level);
72
73  // Sets the zoom level for the specified view. The level may be set for only
74  // this view, or for the host, depending on UsesTemporaryZoomLevel().
75  void SetZoomLevelForView(int render_process_id,
76                           int render_view_id,
77                           double level,
78                           const std::string& host);
79
80  // Returns the temporary zoom level that's only valid for the lifetime of
81  // the given WebContents (i.e. isn't saved and doesn't affect other
82  // WebContentses) if it exists, the default zoom level otherwise.
83  //
84  // This may be called on any thread.
85  double GetTemporaryZoomLevel(int render_process_id,
86                               int render_view_id) const;
87
88  // NotificationObserver implementation.
89  virtual void Observe(int type,
90                       const NotificationSource& source,
91                       const NotificationDetails& details) OVERRIDE;
92
93 private:
94  typedef std::map<std::string, double> HostZoomLevels;
95  typedef std::map<std::string, HostZoomLevels> SchemeHostZoomLevels;
96
97  struct RenderViewKey {
98    int render_process_id;
99    int render_view_id;
100    RenderViewKey(int render_process_id, int render_view_id)
101        : render_process_id(render_process_id),
102          render_view_id(render_view_id) {}
103    bool operator<(const RenderViewKey& other) const {
104      return render_process_id < other.render_process_id ||
105             ((render_process_id == other.render_process_id) &&
106              (render_view_id < other.render_view_id));
107    }
108  };
109
110  typedef std::map<RenderViewKey, double> TemporaryZoomLevels;
111
112  double GetZoomLevelForHost(const std::string& host) const;
113
114  // Notifies the renderers from this browser context to change the zoom level
115  // for the specified host and scheme.
116  // TODO(wjmaclean) Should we use a GURL here? crbug.com/384486
117  void SendZoomLevelChange(const std::string& scheme,
118                           const std::string& host,
119                           double level);
120
121  // Callbacks called when zoom level changes.
122  base::CallbackList<void(const ZoomLevelChange&)>
123      zoom_level_changed_callbacks_;
124
125  // Copy of the pref data, so that we can read it on the IO thread.
126  HostZoomLevels host_zoom_levels_;
127  SchemeHostZoomLevels scheme_host_zoom_levels_;
128  double default_zoom_level_;
129
130  // Don't expect more than a couple of tabs that are using a temporary zoom
131  // level, so vector is fine for now.
132  TemporaryZoomLevels temporary_zoom_levels_;
133
134  // Used around accesses to |host_zoom_levels_|, |default_zoom_level_| and
135  // |temporary_zoom_levels_| to guarantee thread safety.
136  mutable base::Lock lock_;
137
138  NotificationRegistrar registrar_;
139
140  DISALLOW_COPY_AND_ASSIGN(HostZoomMapImpl);
141};
142
143}  // namespace content
144
145#endif  // CONTENT_BROWSER_HOST_ZOOM_MAP_IMPL_H_
146