components/favicon/core/favicon_driver.h

   1 // Copyright 2014 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 COMPONENTS_FAVICON_CORE_FAVICON_DRIVER_H_
   6 #define COMPONENTS_FAVICON_CORE_FAVICON_DRIVER_H_
   7
   8 #include "base/macros.h"
   9 #include "base/observer_list.h"
  10 #include "base/strings/string16.h"
  11
  12 class GURL;
  13
  14 namespace gfx {
  15 class Image;
  16 }
  17
  18 namespace favicon {
  19
  20 class FaviconDriverObserver;
  21
  22 // Interface that allows favicon core code to obtain information about the
  23 // current page. This is partially implemented by FaviconDriverImpl, and
  24 // concrete implementation should be based on that class instead of directly
  25 // subclassing FaviconDriver.
  26 class FaviconDriver {
  27  public:
  28   // Adds/Removes an observer.
  29   void AddObserver(FaviconDriverObserver* observer);
  30   void RemoveObserver(FaviconDriverObserver* observer);
  31
  32   // Initiates loading the favicon for the specified url.
  33   virtual void FetchFavicon(const GURL& url) = 0;
  34
  35   // Returns the favicon for this tab, or IDR_DEFAULT_FAVICON if the tab does
  36   // not have a favicon. The default implementation uses the current navigation
  37   // entry. Returns an empty bitmap if there are no navigation entries, which
  38   // should rarely happen.
  39   virtual gfx::Image GetFavicon() const = 0;
  40
  41   // Returns true if we have the favicon for the page.
  42   virtual bool FaviconIsValid() const = 0;
  43
  44   // Starts the download for the given favicon. When finished, the driver
  45   // will call OnDidDownloadFavicon() with the results.
  46   // Returns the unique id of the download request. The id will be passed
  47   // in OnDidDownloadFavicon().
  48   // Bitmaps with pixel sizes larger than |max_bitmap_size| are filtered out
  49   // from the bitmap results. If there are no bitmap results <=
  50   // |max_bitmap_size|, the smallest bitmap is resized to |max_bitmap_size| and
  51   // is the only result. A |max_bitmap_size| of 0 means unlimited.
  52   virtual int StartDownload(const GURL& url, int max_bitmap_size) = 0;
  53
  54   // Returns whether the user is operating in an off-the-record context.
  55   virtual bool IsOffTheRecord() = 0;
  56
  57   // Returns whether |url| is bookmarked.
  58   virtual bool IsBookmarked(const GURL& url) = 0;
  59
  60   // Returns the URL of the current page, if any. Returns an invalid URL
  61   // otherwise.
  62   virtual GURL GetActiveURL() = 0;
  63
  64   // Returns whether the page's favicon is valid (returns false if the default
  65   // favicon is being used). Requires GetActiveURL() to be valid.
  66   virtual bool GetActiveFaviconValidity() = 0;
  67
  68   // Sets whether the page's favicon is valid (if false, the default favicon is
  69   // being used).
  70   virtual void SetActiveFaviconValidity(bool valid) = 0;
  71
  72   // Returns the URL of the current page's favicon. Requires GetActiveURL() to
  73   // be valid.
  74   virtual GURL GetActiveFaviconURL() = 0;
  75
  76   // Sets the URL of the favicon's bitmap.
  77   virtual void SetActiveFaviconURL(const GURL& url) = 0;
  78
  79   // Sets the bitmap of the current page's favicon.
  80   virtual void SetActiveFaviconImage(const gfx::Image& image) = 0;
  81
  82   // Notifies the driver a favicon image is available. |image| is not
  83   // necessarily 16x16. |icon_url| is the url the image is from. If
  84   // |is_active_favicon| is true the image corresponds to the favicon
  85   // (possibly empty) of the page.
  86   virtual void OnFaviconAvailable(const gfx::Image& image,
  87                                   const GURL& icon_url,
  88                                   bool is_active_favicon) = 0;
  89
  90   // Returns whether the driver is waiting for a download to complete or for
  91   // data from the FaviconService. Reserved for testing.
  92   virtual bool HasPendingTasksForTest() = 0;
  93
  94  protected:
  95   FaviconDriver();
  96   virtual ~FaviconDriver();
  97
  98   // Informs FaviconDriverObservers that favicon |image| has been retrieved from
  99   // either website or cached storage.
 100   void NotifyFaviconAvailable(const gfx::Image& image);
 101
 102   // Informs FaviconDriverObservers that favicon has changed for the current
 103   // page. |icon_url_changed| is true if the favicon URL has also changed since
 104   // the last call.
 105   virtual void NotifyFaviconUpdated(bool icon_url_changed);
 106
 107  private:
 108   base::ObserverList<FaviconDriverObserver> observer_list_;
 109
 110   DISALLOW_COPY_AND_ASSIGN(FaviconDriver);
 111 };
 112
 113 }  // namespace favicon
 114
 115 #endif  // COMPONENTS_FAVICON_CORE_FAVICON_DRIVER_H_