chrome/browser/media_galleries/media_folder_finder.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 CHROME_BROWSER_MEDIA_GALLERIES_MEDIA_FOLDER_FINDER_H_
   6 #define CHROME_BROWSER_MEDIA_GALLERIES_MEDIA_FOLDER_FINDER_H_
   7
   8 #include <map>
   9 #include <vector>
  10
  11 #include "base/callback.h"
  12 #include "base/files/file_path.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/memory/weak_ptr.h"
  15 #include "base/sequenced_task_runner.h"
  16 #include "chrome/browser/media_galleries/media_scan_types.h"
  17
  18 // MediaFolderFinder scans local hard drives and look for folders that contain
  19 // media files.
  20 class MediaFolderFinder {
  21  public:
  22   // Key: path to a folder
  23   // Value: scan results for that folder, non-recursive.
  24   typedef std::map<base::FilePath, MediaGalleryScanResult>
  25       MediaFolderFinderResults;
  26
  27   // |results| never contains entries for |graylisted_folders_| or parent
  28   // directories of |graylisted_folders_|.
  29   typedef base::Callback<void(bool /*success*/,
  30                               const MediaFolderFinderResults& /*results*/)>
  31       MediaFolderFinderResultsCallback;
  32
  33   // |callback| will get called when the scan finishes. If the object is deleted
  34   // before it finishes, the scan will stop and |callback| will get called with
  35   // success = false.
  36   // MediaFolderFinder has a default set of per-platform paths to scan.
  37   // Override in tests with SetRootsForTesting().
  38   explicit MediaFolderFinder(const MediaFolderFinderResultsCallback& callback);
  39   virtual ~MediaFolderFinder();
  40
  41   // Start the scan.
  42   virtual void StartScan();
  43
  44   const std::vector<base::FilePath>& graylisted_folders() const;
  45
  46  private:
  47   friend class MediaFolderFinderTest;
  48   friend class MediaGalleriesPlatformAppBrowserTest;
  49
  50   class Worker;
  51   struct WorkerReply {
  52     WorkerReply();
  53     ~WorkerReply();
  54
  55     MediaGalleryScanResult scan_result;
  56     std::vector<base::FilePath> new_folders;
  57   };
  58
  59   enum ScanState {
  60     SCAN_STATE_NOT_STARTED,
  61     SCAN_STATE_STARTED,
  62     SCAN_STATE_FINISHED,
  63   };
  64
  65   void SetRootsForTesting(const std::vector<base::FilePath>& roots);
  66
  67   void OnInitialized(const std::vector<base::FilePath>& roots);
  68
  69   // Scan a folder from |folders_to_scan_|.
  70   void ScanFolder();
  71
  72   // Callback that handles the |reply| from |worker_| for a scanned |path|.
  73   void GotScanResults(const base::FilePath& path, const WorkerReply& reply);
  74
  75   const MediaFolderFinderResultsCallback results_callback_;
  76   MediaFolderFinderResults results_;
  77
  78   std::vector<base::FilePath> graylisted_folders_;
  79   std::vector<base::FilePath> folders_to_scan_;
  80   ScanState scan_state_;
  81
  82   scoped_refptr<base::SequencedTaskRunner> worker_task_runner_;
  83
  84   // Owned by MediaFolderFinder, but lives on |worker_task_runner_|.
  85   Worker* worker_;
  86
  87   // Set of roots to scan for testing.
  88   bool has_roots_for_testing_;
  89   std::vector<base::FilePath> roots_for_testing_;
  90
  91   base::WeakPtrFactory<MediaFolderFinder> weak_factory_;
  92
  93   DISALLOW_COPY_AND_ASSIGN(MediaFolderFinder);
  94 };
  95
  96 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_MEDIA_FOLDER_FINDER_H_