// Copyright (c) 2012 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 CHROME_BROWSER_UI_TOOLBAR_BACK_FORWARD_MENU_MODEL_H_
#define CHROME_BROWSER_UI_TOOLBAR_BACK_FORWARD_MENU_MODEL_H_
#include <set>
#include <string>
#include "base/basictypes.h"
#include "base/gtest_prod_util.h"
#include "base/strings/string16.h"
#include "base/task/cancelable_task_tracker.h"
#include "chrome/browser/favicon/favicon_service.h"
#include "ui/base/models/menu_model.h"
#include "ui/base/window_open_disposition.h"
class Browser;
namespace chrome {
struct FaviconImageResult;
}
namespace content {
class NavigationEntry;
class WebContents;
}
namespace gfx {
class Image;
}
///////////////////////////////////////////////////////////////////////////////
//
// BackForwardMenuModel
//
// Interface for the showing of the dropdown menu for the Back/Forward buttons.
// Actual implementations are platform-specific.
///////////////////////////////////////////////////////////////////////////////
class BackForwardMenuModel : public ui::MenuModel {
public:
// These are IDs used to identify individual UI elements within the
// browser window using View::GetViewByID.
enum ModelType {
FORWARD_MENU = 1,
BACKWARD_MENU = 2
};
BackForwardMenuModel(Browser* browser, ModelType model_type);
virtual ~BackForwardMenuModel();
// MenuModel implementation.
virtual bool HasIcons() const OVERRIDE;
// Returns how many items the menu should show, including history items,
// chapter-stops, separators and the Show Full History link. This function
// uses GetHistoryItemCount() and GetChapterStopCount() internally to figure
// out the total number of items to show.
virtual int GetItemCount() const OVERRIDE;
virtual ItemType GetTypeAt(int index) const OVERRIDE;
virtual ui::MenuSeparatorType GetSeparatorTypeAt(int index) const OVERRIDE;
virtual int GetCommandIdAt(int index) const OVERRIDE;
virtual base::string16 GetLabelAt(int index) const OVERRIDE;
virtual bool IsItemDynamicAt(int index) const OVERRIDE;
virtual bool GetAcceleratorAt(int index,
ui::Accelerator* accelerator) const OVERRIDE;
virtual bool IsItemCheckedAt(int index) const OVERRIDE;
virtual int GetGroupIdAt(int index) const OVERRIDE;
virtual bool GetIconAt(int index, gfx::Image* icon) OVERRIDE;
virtual ui::ButtonMenuItemModel* GetButtonMenuItemAt(
int index) const OVERRIDE;
virtual bool IsEnabledAt(int index) const OVERRIDE;
virtual MenuModel* GetSubmenuModelAt(int index) const OVERRIDE;
virtual void HighlightChangedTo(int index) OVERRIDE;
virtual void ActivatedAt(int index) OVERRIDE;
virtual void ActivatedAt(int index, int event_flags) OVERRIDE;
virtual void MenuWillShow() OVERRIDE;
// Is the item at |index| a separator?
bool IsSeparator(int index) const;
// Set the delegate for triggering OnIconChanged.
virtual void SetMenuModelDelegate(
ui::MenuModelDelegate* menu_model_delegate) OVERRIDE;
virtual ui::MenuModelDelegate* GetMenuModelDelegate() const OVERRIDE;
protected:
ui::MenuModelDelegate* menu_model_delegate() { return menu_model_delegate_; }
private:
friend class BackFwdMenuModelTest;
FRIEND_TEST_ALL_PREFIXES(BackFwdMenuModelTest, BasicCase);
FRIEND_TEST_ALL_PREFIXES(BackFwdMenuModelTest, MaxItemsTest);
FRIEND_TEST_ALL_PREFIXES(BackFwdMenuModelTest, ChapterStops);
FRIEND_TEST_ALL_PREFIXES(BackFwdMenuModelTest, EscapeLabel);
FRIEND_TEST_ALL_PREFIXES(BackFwdMenuModelTest, FaviconLoadTest);
// Requests a favicon from the FaviconService. Called by GetIconAt if the
// NavigationEntry has an invalid favicon.
void FetchFavicon(content::NavigationEntry* entry);
// Callback from the favicon service.
void OnFavIconDataAvailable(
int navigation_entry_unique_id,
const chrome::FaviconImageResult& image_result);
// Allows the unit test to use its own dummy tab contents.
void set_test_web_contents(content::WebContents* test_web_contents) {
test_web_contents_ = test_web_contents;
}
// Returns how many history items the menu should show. For example, if the
// navigation controller of the current tab has a current entry index of 5 and
// forward_direction_ is false (we are the back button delegate) then this
// function will return 5 (representing 0-4). If forward_direction_ is
// true (we are the forward button delegate), then this function will return
// the number of entries after 5. Note, though, that in either case it will
// not report more than kMaxHistoryItems. The number returned also does not
// include the separator line after the history items (nor the separator for
// the "Show Full History" link).
int GetHistoryItemCount() const;
// Returns how many chapter-stop items the menu should show. For the
// definition of a chapter-stop, see GetIndexOfNextChapterStop(). The number
// returned does not include the separator lines before and after the
// chapter-stops.
int GetChapterStopCount(int history_items) const;
// Finds the next chapter-stop in the NavigationEntryList starting from
// the index specified in |start_from| and continuing in the direction
// specified (|forward|) until either a chapter-stop is found or we reach the
// end, in which case -1 is returned. If |start_from| is out of bounds, -1
// will also be returned. A chapter-stop is defined as the last page the user
// browsed to within the same domain. For example, if the user's homepage is
// Google and she navigates to Google pages G1, G2 and G3 before heading over
// to WikiPedia for pages W1 and W2 and then back to Google for pages G4 and
// G5 then G3, W2 and G5 are considered chapter-stops. The return value from
// this function is an index into the NavigationEntryList vector.
int GetIndexOfNextChapterStop(int start_from, bool forward) const;
// Finds a given chapter-stop starting at the currently active entry in the
// NavigationEntryList vector advancing first forward or backward by |offset|
// (depending on the direction specified in parameter |forward|). It also
// allows you to skip chapter-stops by specifying a positive value for |skip|.
// Example: FindChapterStop(5, false, 3) starts with the currently active
// index, subtracts 5 from it and then finds the fourth chapter-stop before
// that index (skipping the first 3 it finds).
// Example: FindChapterStop(0, true, 0) is functionally equivalent to
// calling GetIndexOfNextChapterStop(GetCurrentEntryIndex(), true).
//
// NOTE: Both |offset| and |skip| must be non-negative. The return value from
// this function is an index into the NavigationEntryList vector. If |offset|
// is out of bounds or if we skip too far (run out of chapter-stops) this
// function returns -1.
int FindChapterStop(int offset, bool forward, int skip) const;
// How many items (max) to show in the back/forward history menu dropdown.
static const int kMaxHistoryItems;
// How many chapter-stops (max) to show in the back/forward dropdown list.
static const int kMaxChapterStops;
// Takes a menu item index as passed in through one of the menu delegate
// functions and converts it into an index into the NavigationEntryList
// vector. |index| can point to a separator, or the
// "Show Full History" link in which case this function returns -1.
int MenuIndexToNavEntryIndex(int index) const;
// Does the item have a command associated with it?
bool ItemHasCommand(int index) const;
// Returns true if there is an icon for this menu item.
bool ItemHasIcon(int index) const;
// Allow the unit test to use the "Show Full History" label.
base::string16 GetShowFullHistoryLabel() const;
// Looks up a NavigationEntry by menu id.
content::NavigationEntry* GetNavigationEntry(int index) const;
// Retrieves the WebContents pointer to use, which is either the one that
// the unit test sets (using set_test_web_contents) or the one from
// the browser window.
content::WebContents* GetWebContents() const;
// Build a string version of a user action on this menu, used as an
// identifier for logging user behavior.
// E.g. BuildActionName("Click", 2) returns "BackMenu_Click2".
// An index of -1 means no index.
std::string BuildActionName(const std::string& name, int index) const;
Browser* browser_;
// The unit tests will provide their own WebContents to use.
content::WebContents* test_web_contents_;
// Represents whether this is the delegate for the forward button or the
// back button.
ModelType model_type_;
// Keeps track of which favicons have already been requested from the history
// to prevent duplicate requests, identified by
// NavigationEntry->GetUniqueID().
std::set<int> requested_favicons_;
// Used for loading favicons.
base::CancelableTaskTracker cancelable_task_tracker_;
// Used for receiving notifications when an icon is changed.
ui::MenuModelDelegate* menu_model_delegate_;
DISALLOW_COPY_AND_ASSIGN(BackForwardMenuModel);
};
#endif // CHROME_BROWSER_UI_TOOLBAR_BACK_FORWARD_MENU_MODEL_H_