1// Copyright (c) 2011 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 CHROME_BROWSER_AUTOMATION_AUTOMATION_TAB_HELPER_H_
6#define CHROME_BROWSER_AUTOMATION_AUTOMATION_TAB_HELPER_H_
7#pragma once
8
9#include <set>
10#include <vector>
11
12#include "base/basictypes.h"
13#include "base/observer_list.h"
14#include "base/memory/weak_ptr.h"
15#include "content/browser/tab_contents/tab_contents_observer.h"
16
17class TabContents;
18class AutomationTabHelper;
19
20namespace IPC {
21class Message;
22}
23
24// An observer API implemented by classes which are interested in various
25// tab events from AutomationTabHelper(s).
26class TabEventObserver {
27 public:
28  // |LOAD_START| and |LOAD_STOP| notifications may occur several times for a
29  // sequence of loads that may appear as one complete navigation to a user.
30  // For instance, navigating to a non-existent page will cause a load start
31  // and stop for the non-existent page; following that, Chrome will schedule
32  // a navigation to an error page which causes another load start and stop.
33  //
34  // A pending load is a load that is currently in progress or one that is
35  // scheduled to occur immediately. The only scheduled loads that are
36  // tracked are client redirects, such as javascript redirects.
37  // TODO(kkania): Handle redirects that are scheduled to occur later, and
38  // change this definition of a pending load.
39  // TODO(kkania): Track other types of scheduled navigations.
40
41  // Called when the tab that had no pending loads now has a new pending
42  // load. |tab_contents| will always be valid.
43  virtual void OnFirstPendingLoad(TabContents* tab_contents) { }
44
45  // Called when the tab that had one or more pending loads now has no
46  // pending loads. |tab_contents| will always be valid.
47  //
48  // This method will always be called if |OnFirstPendingLoad| was called.
49  virtual void OnNoMorePendingLoads(TabContents* tab_contents) { }
50
51 protected:
52  TabEventObserver();
53  virtual ~TabEventObserver();
54
55  // On construction, this class does not observe any events. This method
56  // sets us up to observe events from the given |AutomationTabHelper|.
57  void StartObserving(AutomationTabHelper* tab_helper);
58
59  // Stop observing events from the given |AutomationTabHelper|. This does not
60  // need to be called before the helper dies, and it is ok if this object is
61  // destructed while it is still observing an |AutomationTabHelper|.
62  void StopObserving(AutomationTabHelper* tab_helper);
63
64 private:
65  friend class AutomationTabHelperTest;
66  typedef std::vector<base::WeakPtr<AutomationTabHelper> > EventSourceVector;
67
68  // Vector of all the event sources we are observing. Tracked so that this
69  // class can remove itself from each source at its destruction.
70  EventSourceVector event_sources_;
71
72  DISALLOW_COPY_AND_ASSIGN(TabEventObserver);
73};
74
75// Per-tab automation support class. Receives automation/testing messages
76// from the renderer. Broadcasts tab events to |TabEventObserver|s.
77class AutomationTabHelper
78    : public TabContentsObserver,
79      public base::SupportsWeakPtr<AutomationTabHelper> {
80 public:
81  explicit AutomationTabHelper(TabContents* tab_contents);
82  virtual ~AutomationTabHelper();
83
84  void AddObserver(TabEventObserver* observer);
85  void RemoveObserver(TabEventObserver* observer);
86
87  // Returns true if the tab is loading or the tab is scheduled to load
88  // immediately. Note that scheduled loads may be canceled.
89  bool has_pending_loads() const;
90
91 private:
92  friend class AutomationTabHelperTest;
93
94  // TabContentsObserver implementation.
95  virtual void DidStartLoading();
96  virtual void DidStopLoading();
97  virtual void RenderViewGone();
98  virtual void TabContentsDestroyed(TabContents* tab_contents);
99  virtual bool OnMessageReceived(const IPC::Message& message);
100
101  void OnWillPerformClientRedirect(int64 frame_id, double delay_seconds);
102  void OnDidCompleteOrCancelClientRedirect(int64 frame_id);
103  void OnTabOrRenderViewDestroyed(TabContents* tab_contents);
104
105  // True if the tab is currently loading. If a navigation is scheduled but not
106  // yet loading, this will be false.
107  bool is_loading_;
108
109  // Set of all the frames (by frame ID) that are scheduled to perform a client
110  // redirect.
111  std::set<int64> pending_client_redirects_;
112
113  // List of all the |TabEventObserver|s, which we broadcast events to.
114  ObserverList<TabEventObserver> observers_;
115
116  DISALLOW_COPY_AND_ASSIGN(AutomationTabHelper);
117};
118
119#endif  // CHROME_BROWSER_AUTOMATION_AUTOMATION_TAB_HELPER_H_
120