chrome/browser/ash/fileapi/recent_arc_media_source.h

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_ASH_FILEAPI_RECENT_ARC_MEDIA_SOURCE_H_
#define CHROME_BROWSER_ASH_FILEAPI_RECENT_ARC_MEDIA_SOURCE_H_

#include <memory>
#include <optional>
#include <vector>

#include "base/gtest_prod_util.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/time/time.h"
#include "chrome/browser/ash/fileapi/recent_source.h"

class Profile;

namespace ash {

class RecentFile;

// RecentSource implementation for ARC media view.
//
// All member functions must be called on the UI thread.
class RecentArcMediaSource : public RecentSource {
 public:
  // Creates a recent file sources that scans Arc media. The `profile` is used
  // to create scanners for all known media roots (Documents, Movies, etc.). The
  // `max_files` parameter limits the maximum number of files returned by this
  // source to the callback specified in the parameters of the GetRecentFiles
  // method.
  RecentArcMediaSource(Profile* profile, size_t max_files);

  RecentArcMediaSource(const RecentArcMediaSource&) = delete;
  RecentArcMediaSource& operator=(const RecentArcMediaSource&) = delete;

  ~RecentArcMediaSource() override;

  // RecentSource overrides:
  void GetRecentFiles(Params params, GetRecentFilesCallback callback) override;

 private:
  FRIEND_TEST_ALL_PREFIXES(RecentArcMediaSourceTest, UmaStats);
  FRIEND_TEST_ALL_PREFIXES(RecentArcMediaSourceTest, UmaStats_Deferred);

  class MediaRoot;

  static const char kLoadHistogramName[];

  void OnGetRecentFilesForRoot(std::vector<RecentFile> files);
  void OnComplete();

  bool WillArcFileSystemOperationsRunImmediately();

  const raw_ptr<Profile> profile_;
  std::vector<std::unique_ptr<MediaRoot>> roots_;

  // Time when the build started.
  base::TimeTicks build_start_time_;

  int num_inflight_roots_ = 0;
  std::vector<RecentFile> files_;

  const size_t max_files_;

  // The callback to be called once all files are gathered. We do not know ahead
  // of time when this may be the case, due to nested directories. Thus this
  // class behaves similarly to a Barrier class, except that the number of times
  // the barrier has to be called varies.
  GetRecentFilesCallback callback_;

  base::WeakPtrFactory<RecentArcMediaSource> weak_ptr_factory_{this};
};

}  // namespace ash

#endif  // CHROME_BROWSER_ASH_FILEAPI_RECENT_ARC_MEDIA_SOURCE_H_