[cros login] Split login related classes into subfolders.

chrome/browser/chromeos/login/user_image_loader.h

-// Copyright (c) 2013 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_CHROMEOS_LOGIN_USER_IMAGE_LOADER_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_USER_IMAGE_LOADER_H_
-
-#include <map>
-#include <string>
-
-#include "base/callback.h"
-#include "base/compiler_specific.h"
-#include "base/memory/ref_counted.h"
-#include "chrome/browser/image_decoder.h"
-
-class SkBitmap;
-
-namespace base {
-class SequencedTaskRunner;
-}
-
-namespace chromeos {
-
-class UserImage;
-
-// Helper that reads, decodes and optionally resizes an image on a background
-// thread. Returns the image in the form of an SkBitmap.
-class UserImageLoader : public base::RefCountedThreadSafe<UserImageLoader>,
-                        public ImageDecoder::Delegate {
- public:
-  // Callback used to return the result of an image load operation.
-  typedef base::Callback<void(const UserImage& user_image)> LoadedCallback;
-
-  // All file I/O, decoding and resizing are done via |background_task_runner|.
-  UserImageLoader(
-      ImageDecoder::ImageCodec image_codec,
-      scoped_refptr<base::SequencedTaskRunner> background_task_runner);
-
-  // Load an image in the background and call |loaded_cb| with the resulting
-  // UserImage (which may be empty in case of error). If |pixels_per_side| is
-  // positive, the image is cropped to a square and shrunk so that it does not
-  // exceed |pixels_per_side|x|pixels_per_side|. The first variant of this
-  // method reads the image from |filepath| on disk, the second processes |data|
-  // read into memory already.
-  void Start(const std::string& filepath,
-             int pixels_per_side,
-             const LoadedCallback& loaded_cb);
-  void Start(scoped_ptr<std::string> data,
-             int pixels_per_side,
-             const LoadedCallback& loaded_cb);
-
- private:
-  friend class base::RefCountedThreadSafe<UserImageLoader>;
-
-  // Contains attributes we need to know about each image we decode.
-  struct ImageInfo {
-    ImageInfo(const std::string& file_path,
-              int pixels_per_side,
-              const LoadedCallback& loaded_cb);
-    ~ImageInfo();
-
-    const std::string file_path;
-    const int pixels_per_side;
-    const LoadedCallback loaded_cb;
-  };
-
-  typedef std::map<const ImageDecoder*, ImageInfo> ImageInfoMap;
-
-  virtual ~UserImageLoader();
-
-  // Reads the image from |image_info.file_path| and starts the decoding
-  // process. This method may only be invoked via the |background_task_runner_|.
-  void ReadAndDecodeImage(const ImageInfo& image_info);
-
-  // Decodes the image |data|. This method may only be invoked via the
-  // |background_task_runner_|.
-  void DecodeImage(const scoped_ptr<std::string> data,
-                   const ImageInfo& image_info);
-
-  // ImageDecoder::Delegate implementation. These callbacks will only be invoked
-  // via the |background_task_runner_|.
-  virtual void OnImageDecoded(const ImageDecoder* decoder,
-                              const SkBitmap& decoded_image) OVERRIDE;
-  virtual void OnDecodeImageFailed(const ImageDecoder* decoder) OVERRIDE;
-
-  // The foreground task runner on which |this| is instantiated, Start() is
-  // called and LoadedCallbacks are invoked.
-  scoped_refptr<base::SequencedTaskRunner> foreground_task_runner_;
-
-  // The background task runner on which file I/O, image decoding and resizing
-  // are done.
-  scoped_refptr<base::SequencedTaskRunner> background_task_runner_;
-
-  // Specify how the file should be decoded in the utility process.
-  const ImageDecoder::ImageCodec image_codec_;
-
-  // Holds information about the images currently being decoded. Accessed via
-  // |background_task_runner_| only.
-  ImageInfoMap image_info_map_;
-
-  DISALLOW_COPY_AND_ASSIGN(UserImageLoader);
-};
-
-}  // namespace chromeos
-
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USER_IMAGE_LOADER_H_