WIP - Refactor programmatic downloads

content/browser/download/download_manager_impl.cc

Index: content/browser/download/download_manager_impl.cc
diff --git a/content/browser/download/download_manager_impl.cc b/content/browser/download/download_manager_impl.cc
index ccfb4cc0a5111a7eb5fcfd0ba87060ded15cf770..4ccab3a3e1c9fcd4d605664a248e4e29ae339aa7 100644
--- a/content/browser/download/download_manager_impl.cc
+++ b/content/browser/download/download_manager_impl.cc
@@ -24,6 +24,7 @@
 #include "content/browser/download/download_item_factory.h"
 #include "content/browser/download/download_item_impl.h"
 #include "content/browser/download/download_stats.h"
+#include "content/browser/download/url_downloader.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
@@ -47,91 +48,6 @@
 namespace content {
 namespace {
 
-void BeginDownload(scoped_ptr<DownloadUrlParameters> params,
-                   uint32 download_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  // ResourceDispatcherHost{Base} is-not-a URLRequest::Delegate, and
-  // DownloadUrlParameters can-not include resource_dispatcher_host_impl.h, so
-  // we must down cast. RDHI is the only subclass of RDH as of 2012 May 4.
-  scoped_ptr<net::URLRequest> request(
-      params->resource_context()->GetRequestContext()->CreateRequest(
-          params->url(), NULL));
-  request->set_load_flags(request->load_flags() | params->load_flags());
-  request->set_method(params->method());
-  if (!params->post_body().empty()) {
-    const std::string& body = params->post_body();
-    scoped_ptr<net::UploadElementReader> reader(
-        net::UploadOwnedBytesElementReader::CreateWithString(body));
-    request->set_upload(make_scoped_ptr(
-        net::UploadDataStream::CreateWithReader(reader.Pass(), 0)));
-  }
-  if (params->post_id() >= 0) {
-    // The POST in this case does not have an actual body, and only works
-    // when retrieving data from cache. This is done because we don't want
-    // to do a re-POST without user consent, and currently don't have a good
-    // plan on how to display the UI for that.
-    DCHECK(params->prefer_cache());
-    DCHECK(params->method() == "POST");
-    ScopedVector<net::UploadElementReader> element_readers;
-    request->set_upload(make_scoped_ptr(
-        new net::UploadDataStream(&element_readers, params->post_id())));
-  }
-
-  // If we're not at the beginning of the file, retrieve only the remaining
-  // portion.
-  bool has_last_modified = !params->last_modified().empty();
-  bool has_etag = !params->etag().empty();
-
-  // If we've asked for a range, we want to make sure that we only
-  // get that range if our current copy of the information is good.
-  // We shouldn't be asked to continue if we don't have a verifier.
-  DCHECK(params->offset() == 0 || has_etag || has_last_modified);
-
-  if (params->offset() > 0) {
-    request->SetExtraRequestHeaderByName(
-        "Range",
-        base::StringPrintf("bytes=%" PRId64 "-", params->offset()),
-        true);
-
-    if (has_last_modified) {
-      request->SetExtraRequestHeaderByName("If-Unmodified-Since",
-                                           params->last_modified(),
-                                           true);
-    }
-    if (has_etag) {
-      request->SetExtraRequestHeaderByName("If-Match", params->etag(), true);
-    }
-  }
-
-  for (DownloadUrlParameters::RequestHeadersType::const_iterator iter
-           = params->request_headers_begin();
-       iter != params->request_headers_end();
-       ++iter) {
-    request->SetExtraRequestHeaderByName(
-        iter->first, iter->second, false/*overwrite*/);
-  }
-
-  scoped_ptr<DownloadSaveInfo> save_info(new DownloadSaveInfo());
-  save_info->file_path = params->file_path();
-  save_info->suggested_name = params->suggested_name();
-  save_info->offset = params->offset();
-  save_info->hash_state = params->hash_state();
-  save_info->prompt_for_save_location = params->prompt();
-  save_info->file_stream = params->GetFileStream();
-
-  ResourceDispatcherHost::Get()->BeginDownload(
-      request.Pass(),
-      params->referrer(),
-      params->content_initiated(),
-      params->resource_context(),
-      params->render_process_host_id(),
-      params->render_view_host_routing_id(),
-      params->prefer_cache(),
-      save_info.Pass(),
-      download_id,
-      params->callback());
-}
-
 class MapValueIteratorAdapter {
  public:
   explicit MapValueIteratorAdapter(
@@ -213,19 +129,6 @@ class DownloadItemFactoryImpl : public DownloadItemFactory {
       const net::BoundNetLog& bound_net_log) OVERRIDE {
     return new DownloadItemImpl(delegate, download_id, info, bound_net_log);
   }
-
-  virtual DownloadItemImpl* CreateSavePageItem(
-      DownloadItemImplDelegate* delegate,
-      uint32 download_id,
-      const base::FilePath& path,
-      const GURL& url,
-      const std::string& mime_type,
-      scoped_ptr<DownloadRequestHandleInterface> request_handle,
-      const net::BoundNetLog& bound_net_log) OVERRIDE {
-    return new DownloadItemImpl(delegate, download_id, path, url,
-                                mime_type, request_handle.Pass(),
-                                bound_net_log);
-  }
 };
 
 }  // namespace
@@ -249,7 +152,8 @@ DownloadManagerImpl::~DownloadManagerImpl() {
 }
 
 DownloadItemImpl* DownloadManagerImpl::CreateActiveItem(
-    uint32 id, const DownloadCreateInfo& info) {
+    uint32 id,
+    const DownloadCreateInfo& info) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!ContainsKey(downloads_, id));
   net::BoundNetLog bound_net_log =
@@ -356,54 +260,74 @@ void DownloadManagerImpl::Shutdown() {
   delegate_ = NULL;
 }
 
-void DownloadManagerImpl::StartDownload(
-    scoped_ptr<DownloadCreateInfo> info,
-    scoped_ptr<ByteStreamReader> stream,
-    const DownloadUrlParameters::OnStartedCallback& on_started) {
+void DownloadManagerImpl::StartDownloadWithActiveRequest(
+    scoped_ptr<DownloadRequestHandle> request_handle,
+    scoped_ptr<DownloadCreateInfo> info) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(info);
-  uint32 download_id = info->download_id;
-  const bool new_download = (download_id == content::DownloadItem::kInvalidId);
-  base::Callback<void(uint32)> got_id(base::Bind(
-      &DownloadManagerImpl::StartDownloadWithId,
-      weak_factory_.GetWeakPtr(),
-      base::Passed(info.Pass()),
-      base::Passed(stream.Pass()),
-      on_started,
-      new_download));
-  if (new_download) {
-    GetNextId(got_id);
-  } else {
-    got_id.Run(download_id);
-  }
+  GetNextId(base::Bind(&DownloadManagerImpl::StartDownloadWithId,
+                       weak_factory_.GetWeakPtr(),
+                       base::Passed(&request_handle),
+                       base::Passed(&info)));
 }
 
 void DownloadManagerImpl::StartDownloadWithId(
+    scoped_ptr<DownloadRequestHandle> request_handle,
     scoped_ptr<DownloadCreateInfo> info,
-    scoped_ptr<ByteStreamReader> stream,
-    const DownloadUrlParameters::OnStartedCallback& on_started,
-    bool new_download,
     uint32 id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  DCHECK_NE(content::DownloadItem::kInvalidId, id);
-  DownloadItemImpl* download = NULL;
-  if (new_download) {
-    download = CreateActiveItem(id, *info);
-  } else {
-    DownloadMap::iterator item_iterator = downloads_.find(id);
-    // Trying to resume an interrupted download.
-    if (item_iterator == downloads_.end() ||
-        (item_iterator->second->GetState() == DownloadItem::CANCELLED)) {
-      // If the download is no longer known to the DownloadManager, then it was
-      // removed after it was resumed. Ignore. If the download is cancelled
-      // while resuming, then also ignore the request.
-      info->request_handle.CancelRequest();
-      if (!on_started.is_null())
-        on_started.Run(NULL, net::ERR_ABORTED);
-      return;
-    }
-    download = item_iterator->second;
-    DCHECK_EQ(DownloadItem::INTERRUPTED, download->GetState());
+  pending_requests_.push_back(request_handle.release());
+  OnDownloadRequestStarted(id,
+                           true /* new download */,
+                           DownloadUrlParameters::OnStartedCallback(),
+                           pending_requests_.back(),
+                           DOWNLOAD_INTERRUPT_REASON_NONE,
+                           info.Pass());
+}
+
+DownloadItemImpl* DownloadManagerImpl::UpdateAndGetResumedDownloadItem(
+    uint32 download_id,
+    DownloadRequestHandle* request_handle,
+    const DownloadCreateInfo& new_create_info) {
+  DownloadMap::iterator item_iterator = downloads_.find(download_id);
+  // Trying to resume an interrupted download.
+  if (item_iterator == downloads_.end() ||
+      (item_iterator->second->GetState() == DownloadItem::CANCELLED)) {
+    // If the download is no longer known to the DownloadManager, then it was
+    // removed after it was resumed. Ignore. If the download is cancelled
+    // while resuming, then also ignore the request.
+    request_handle->CancelRequest();
+    return NULL;
+  }
+  DownloadItemImpl* download = item_iterator->second;
+  DCHECK_EQ(DownloadItem::INTERRUPTED, download->GetState());
+  download->MergeOriginInfoOnResume(new_create_info);
+  return download;
+}
+
+void DownloadManagerImpl::OnDownloadRequestStarted(
+    uint32 download_id,
+    bool new_download,
+    const DownloadUrlParameters::OnStartedCallback& on_started,
+    DownloadRequestHandle* request_handle,
+    DownloadInterruptReason interrupt_reason,
+    scoped_ptr<DownloadCreateInfo> info) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_NE(content::DownloadItem::kInvalidId, download_id);
+  DCHECK(info);
+  ScopedVector<DownloadRequestHandle>::iterator handle_iter = std::find(
+      pending_requests_.begin(), pending_requests_.end(), request_handle);
+  DCHECK(pending_requests_.end() != handle_iter);
+  pending_requests_.weak_erase(handle_iter);
+  scoped_ptr<DownloadRequestHandle> owned_request_handle(request_handle);
+  DownloadItemImpl* download =
+      new_download
+          ? CreateActiveItem(download_id, *info)
+          : UpdateAndGetResumedDownloadItem(download_id, request_handle, *info);
+  if (!download) {
+    if (!on_started.is_null())
+      on_started.Run(NULL, DOWNLOAD_INTERRUPT_REASON_USER_CANCELED);
+    return;
   }
 
   base::FilePath default_download_directory;
@@ -416,12 +340,14 @@ void DownloadManagerImpl::StartDownloadWithId(
 
   // Create the download file and start the download.
   scoped_ptr<DownloadFile> download_file(
-      file_factory_->CreateFile(
-          info->save_info.Pass(), default_download_directory,
-          info->url(), info->referrer_url,
-          delegate_->GenerateFileHash(),
-          stream.Pass(), download->GetBoundNetLog(),
-          download->DestinationObserverAsWeakPtr()));
+      file_factory_->CreateFile(info->save_info.Pass(),
+                                default_download_directory,
+                                info->url(),
+                                info->referrer_url,
+                                delegate_->GenerateFileHash(),
+                                info->stream_reader.Pass(),
+                                download->GetBoundNetLog(),
+                                download->DestinationObserverAsWeakPtr()));
 
   // Attach the client ID identifying the app to the AV system.
   if (download_file.get() && delegate_) {
@@ -429,9 +355,7 @@ void DownloadManagerImpl::StartDownloadWithId(
         delegate_->ApplicationClientIdForFileScanning());
   }
 
-  scoped_ptr<DownloadRequestHandleInterface> req_handle(
-      new DownloadRequestHandle(info->request_handle));
-  download->Start(download_file.Pass(), req_handle.Pass());
+  download->Start(download_file.Pass(), owned_request_handle.Pass());
 
   // For interrupted downloads, Start() will transition the state to
   // IN_PROGRESS and consumers will be notified via OnDownloadUpdated().
@@ -442,7 +366,7 @@ void DownloadManagerImpl::StartDownloadWithId(
     FOR_EACH_OBSERVER(Observer, observers_, OnDownloadCreated(this, download));
 
   if (!on_started.is_null())
-    on_started.Run(download, net::OK);
+    on_started.Run(download, DOWNLOAD_INTERRUPT_REASON_NONE);
 }
 
 void DownloadManagerImpl::CheckForHistoryFilesRemoval() {
@@ -466,6 +390,27 @@ void DownloadManagerImpl::CheckForFileRemoval(DownloadItemImpl* download_item) {
   }
 }
 
+void DownloadManagerImpl::DownloadUrlWithId(
+    scoped_ptr<DownloadUrlParameters> params,
+    bool new_download,
+    uint32 download_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_NE(DownloadItem::kInvalidId, download_id);
+  DownloadUrlParameters::OnStartedCallback on_started_callback =
+      params->callback();
+  scoped_ptr<DownloadRequestHandle> request_handle(
+      UrlDownloader::CreateDownloadRequest(params.Pass()));
+  pending_requests_.push_back(request_handle.release());
+  DownloadRequestHandle::RequestStartedCallback started_callback =
+      base::Bind(&DownloadManagerImpl::OnDownloadRequestStarted,
+                 weak_factory_.GetWeakPtr(),
+                 download_id,
+                 new_download,
+                 on_started_callback,
+                 pending_requests_.back());
+  pending_requests_.back()->Start(started_callback);
+}
+
 void DownloadManagerImpl::OnFileExistenceChecked(uint32 download_id,
                                                  bool result) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
@@ -480,47 +425,25 @@ BrowserContext* DownloadManagerImpl::GetBrowserContext() const {
 }
 
 void DownloadManagerImpl::CreateSavePackageDownloadItem(
-    const base::FilePath& main_file_path,
-    const GURL& page_url,
-    const std::string& mime_type,
-    scoped_ptr<DownloadRequestHandleInterface> request_handle,
-    const DownloadItemImplCreated& item_created) {
+    scoped_ptr<DownloadCreateInfo> create_info,
+    const DownloadItemImplCreated& download_created_callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  GetNextId(base::Bind(
-      &DownloadManagerImpl::CreateSavePackageDownloadItemWithId,
-      weak_factory_.GetWeakPtr(),
-      main_file_path,
-      page_url,
-      mime_type,
-      base::Passed(request_handle.Pass()),
-      item_created));
+  DCHECK(create_info->is_save_package_download);
+
+  GetNextId(
+      base::Bind(&DownloadManagerImpl::CreateSavePackageDownloadItemWithId,
+                 weak_factory_.GetWeakPtr(),
+                 base::Passed(&create_info),
+                 download_created_callback));
 }
 
 void DownloadManagerImpl::CreateSavePackageDownloadItemWithId(
-    const base::FilePath& main_file_path,
-    const GURL& page_url,
-    const std::string& mime_type,
-    scoped_ptr<DownloadRequestHandleInterface> request_handle,
-    const DownloadItemImplCreated& item_created,
+    scoped_ptr<DownloadCreateInfo> create_info,
+    const DownloadItemImplCreated& download_created_callback,
     uint32 id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  DCHECK_NE(content::DownloadItem::kInvalidId, id);
-  DCHECK(!ContainsKey(downloads_, id));
-  net::BoundNetLog bound_net_log =
-      net::BoundNetLog::Make(net_log_, net::NetLog::SOURCE_DOWNLOAD);
-  DownloadItemImpl* download_item = item_factory_->CreateSavePageItem(
-      this,
-      id,
-      main_file_path,
-      page_url,
-      mime_type,
-      request_handle.Pass(),
-      bound_net_log);
-  downloads_[download_item->GetId()] = download_item;
-  FOR_EACH_OBSERVER(Observer, observers_, OnDownloadCreated(
-      this, download_item));
-  if (!item_created.is_null())
-    item_created.Run(download_item);
+  DownloadItemImpl* item = CreateActiveItem(id, *create_info);
+  download_created_callback.Run(item);
 }
 
 void DownloadManagerImpl::OnSavePackageSuccessfullyFinished(
@@ -536,10 +459,7 @@ void DownloadManagerImpl::ResumeInterruptedDownload(
     scoped_ptr<content::DownloadUrlParameters> params,
     uint32 id) {
   RecordDownloadSource(INITIATED_BY_RESUMPTION);
-  BrowserThread::PostTask(
-      BrowserThread::IO,
-      FROM_HERE,
-      base::Bind(&BeginDownload, base::Passed(&params), id));
+  DownloadUrlWithId(params.Pass(), false /* new_download */, id);
 }
 
 void DownloadManagerImpl::SetDownloadItemFactoryForTesting(
@@ -607,9 +527,11 @@ void DownloadManagerImpl::DownloadUrl(
     DCHECK(params->prefer_cache());
     DCHECK(params->method() == "POST");
   }
-  BrowserThread::PostTask(BrowserThread::IO, FROM_HERE, base::Bind(
-      &BeginDownload, base::Passed(&params),
-      content::DownloadItem::kInvalidId));
+
+  GetNextId(base::Bind(&DownloadManagerImpl::DownloadUrlWithId,
+                       weak_factory_.GetWeakPtr(),
+                       base::Passed(&params),
+                       true /* new_download */));
 }
 
 void DownloadManagerImpl::AddObserver(Observer* observer) {