WIP - Refactor programmatic downloads

content/browser/download/download_request_handle.h

 // Copyright (c) 2012 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 CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_HANDLE_H_
 #define CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_HANDLE_H_
 
 #include <string>
 
-#include "base/compiler_specific.h"
-#include "base/memory/weak_ptr.h"
-#include "content/browser/download/download_resource_handler.h"
+#include "base/callback_forward.h"
+#include "base/memory/scoped_ptr.h"
 #include "content/common/content_export.h"
+#include "content/public/browser/download_interrupt_reasons.h"
 
 namespace content {
-class DownloadManager;
-class WebContents;
+struct DownloadCreateInfo;
 
-// A handle used by the download system for operations on the URLRequest
-// or objects conditional on it (e.g. WebContentsImpl).
-// This class needs to be copyable, so we can pass it across threads and not
-// worry about lifetime or const-ness.
-//
-// DownloadRequestHandleInterface is defined for mocking purposes.
-class CONTENT_EXPORT DownloadRequestHandleInterface {
+// A handle used by the download system for operations on the URLRequest.
+class CONTENT_EXPORT DownloadRequestHandle {
  public:
-  virtual ~DownloadRequestHandleInterface() {}
+  typedef base::Callback<
+      void(DownloadInterruptReason, scoped_ptr<DownloadCreateInfo>)>
+      RequestStartedCallback;
 
-  // These functions must be called on the UI thread.
-  virtual WebContents* GetWebContents() const = 0;
-  virtual DownloadManager* GetDownloadManager() const = 0;
+  virtual ~DownloadRequestHandle();
 
-  // Pauses or resumes the matching URL request.
+  // Start the request.
+  virtual void Start(const RequestStartedCallback& callback) = 0;
+
+  // Pauses or resumes the matching URL request. Every call to PauseRequest()
+  // should be balanced with a call to ResumeRequest().
   virtual void PauseRequest() const = 0;
   virtual void ResumeRequest() const = 0;
 
   // Cancels the request.
   virtual void CancelRequest() const = 0;
 
   // Describes the object.
   virtual std::string DebugString() const = 0;
 };
 
-
-class CONTENT_EXPORT DownloadRequestHandle
-    : public DownloadRequestHandleInterface {
- public:
-  virtual ~DownloadRequestHandle();
-
-  // Create a null DownloadRequestHandle: getters will return null, and
-  // all actions are no-ops.
-  // TODO(rdsmith): Ideally, actions would be forbidden rather than
-  // no-ops, to confirm that no non-testing code actually uses
-  // a null DownloadRequestHandle.  But for now, we need the no-op
-  // behavior for unit tests.  Long-term, this should be fixed by
-  // allowing mocking of ResourceDispatcherHost in unit tests.
-  DownloadRequestHandle();
-
-  // Note that |rdh| is required to be non-null.
-  DownloadRequestHandle(const base::WeakPtr<DownloadResourceHandler>& handler,
-                        int child_id,
-                        int render_view_id,
-                        int request_id);
-
-  // Implement DownloadRequestHandleInterface interface.
-  virtual WebContents* GetWebContents() const OVERRIDE;
-  virtual DownloadManager* GetDownloadManager() const OVERRIDE;
-  virtual void PauseRequest() const OVERRIDE;
-  virtual void ResumeRequest() const OVERRIDE;
-  virtual void CancelRequest() const OVERRIDE;
-  virtual std::string DebugString() const OVERRIDE;
-
- private:
-  base::WeakPtr<DownloadResourceHandler> handler_;
-
-  // The ID of the child process that started the download.
-  int child_id_;
-
-  // The ID of the render view that started the download.
-  int render_view_id_;
-
-  // The ID associated with the request used for the download.
-  int request_id_;
-};
-
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_HANDLE_H_