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   typedef std::map<base::FilePath, MediaGalleryScanResult>
  23       MediaFolderFinderResults;
  24   typedef base::Callback<void(bool /*success*/,
  25                               const MediaFolderFinderResults& /*results*/)>
  26       MediaFolderFinderResultsCallback;
  27
  28   // |callback| will get called when the scan finishes. If the object is deleted
  29   // before it finishes, the scan will stop and |callback| will get called with
  30   // success = false.
  31   // MediaFolderFinder has a default set of per-platform paths to scan.
  32   // Override in tests with SetRootsForTesting().
  33   explicit MediaFolderFinder(const MediaFolderFinderResultsCallback& callback);
  34   virtual ~MediaFolderFinder();
  35
  36   // Start the scan.
  37   virtual void StartScan();
  38
  39  private:
  40   friend class MediaFolderFinderTest;
  41
  42   class Worker;
  43   struct WorkerReply {
  44     WorkerReply();
  45     ~WorkerReply();
  46
  47     MediaGalleryScanResult scan_result;
  48     std::vector<base::FilePath> new_folders;
  49   };
  50
  51   enum ScanState {
  52     SCAN_STATE_NOT_STARTED,
  53     SCAN_STATE_STARTED,
  54     SCAN_STATE_FINISHED,
  55   };
  56
  57   void SetRootsForTesting(const std::vector<base::FilePath>& roots);
  58
  59   void OnInitialized(const std::vector<base::FilePath>& roots);
  60
  61   // Scan a folder from |folders_to_scan_|.
  62   void ScanFolder();
  63
  64   // Callback that handles the |reply| from |worker_| for a scanned |path|.
  65   void GotScanResults(const base::FilePath& path, const WorkerReply& reply);
  66
  67   const MediaFolderFinderResultsCallback results_callback_;
  68   MediaFolderFinderResults results_;
  69
  70   std::vector<base::FilePath> folders_to_scan_;
  71   ScanState scan_state_;
  72
  73   scoped_refptr<base::SequencedTaskRunner> worker_task_runner_;
  74
  75   // Owned by MediaFolderFinder, but lives on |worker_task_runner_|.
  76   Worker* worker_;
  77
  78   // Set of roots to scan for testing.
  79   bool has_roots_for_testing_;
  80   std::vector<base::FilePath> roots_for_testing_;
  81
  82   base::WeakPtrFactory<MediaFolderFinder> weak_factory_;
  83
  84   DISALLOW_COPY_AND_ASSIGN(MediaFolderFinder);
  85 };
  86
  87 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_MEDIA_FOLDER_FINDER_H_