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// Copyright 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 CC_RESOURCES_SCOPED_UI_RESOURCE_H_
#define CC_RESOURCES_SCOPED_UI_RESOURCE_H_

#include "base/memory/ref_counted.h"
#include "cc/base/cc_export.h"
#include "cc/resources/ui_resource_bitmap.h"
#include "cc/resources/ui_resource_client.h"
#include "ui/gfx/size.h"

namespace cc {

class LayerTreeHost;

// ScopedUIResource creates an UIResource from a bitmap and a LayerTreeHost.
// This class holds a pointer to the host so that when the instance goes out of
// scope, the created resource is deleted.  On a GetBitmap call from the
// UIResource manager, ScopeUIResource always returns the reference to the
// initially given bitmap regardless of whether the request was due to lost
// resource or not.
class CC_EXPORT ScopedUIResource : public UIResourceClient {
 public:
  static scoped_ptr<ScopedUIResource> Create(LayerTreeHost* host,
                                             const UIResourceBitmap& bitmap);
  virtual ~ScopedUIResource();

  // UIResourceClient implementation.
  virtual UIResourceBitmap GetBitmap(UIResourceId uid,
                                     bool resource_lost) OVERRIDE;
  UIResourceId id() { return id_; }

 protected:
  ScopedUIResource(LayerTreeHost* host, const UIResourceBitmap& bitmap);

  UIResourceBitmap bitmap_;
  LayerTreeHost* host_;
  UIResourceId id_;

 private:
  DISALLOW_COPY_AND_ASSIGN(ScopedUIResource);
};

}  // namespace cc

#endif  // CC_RESOURCES_SCOPED_UI_RESOURCE_H_