Add drive::FileSystem::GetFileByPathForSaving().

chrome/browser/chromeos/drive/file_system/get_file_for_saving_operation.cc

Index: chrome/browser/chromeos/drive/file_system/get_file_for_saving_operation.cc
diff --git a/chrome/browser/chromeos/drive/file_system/get_file_for_saving_operation.cc b/chrome/browser/chromeos/drive/file_system/get_file_for_saving_operation.cc
new file mode 100644
index 0000000000000000000000000000000000000000..79648764d98c93dc08f83e8d70256e9c319bd959
--- /dev/null
+++ b/chrome/browser/chromeos/drive/file_system/get_file_for_saving_operation.cc
@@ -0,0 +1,146 @@
+// 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.
+
+#include "chrome/browser/chromeos/drive/file_system/get_file_for_saving_operation.h"
+
+#include "base/bind.h"
+#include "chrome/browser/chromeos/drive/file_system/create_file_operation.h"
+#include "chrome/browser/chromeos/drive/file_system/download_operation.h"
+#include "chrome/browser/chromeos/drive/file_write_watcher.h"
+#include "content/public/browser/browser_thread.h"
+
+using content::BrowserThread;
+
+namespace drive {
+namespace file_system {
+
+GetFileForSavingOperation::GetFileForSavingOperation(
+    base::SequencedTaskRunner* blocking_task_runner,
+    OperationObserver* observer,
+    JobScheduler* scheduler,
+    internal::ResourceMetadata* metadata,
+    internal::FileCache* cache,
+    const base::FilePath& temporary_file_directory)
+    : create_file_operation_(new CreateFileOperation(blocking_task_runner,
+                                                     observer,
+                                                     scheduler,
+                                                     metadata,
+                                                     cache)),
+      download_operation_(new DownloadOperation(blocking_task_runner,
+                                                observer,
+                                                scheduler,
+                                                metadata,
+                                                cache,
+                                                temporary_file_directory)),
+      file_write_watcher_(new internal::FileWriteWatcher(observer)),
+      cache_(cache),
+      weak_ptr_factory_(this) {
+}
+
+GetFileForSavingOperation::~GetFileForSavingOperation() {
+}
+
+void GetFileForSavingOperation::GetFileForSaving(
+    const base::FilePath& file_path,
+    const GetFileCallback& callback) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(!callback.is_null());
+
+  create_file_operation_->CreateFile(
+      file_path,
+      false,  // error_if_already_exists
+      base::Bind(&GetFileForSavingOperation::GetFileForSavingAfterCreate,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 file_path,
+                 callback));
+}
+
+void GetFileForSavingOperation::GetFileForSavingAfterCreate(
+    const base::FilePath& file_path,
+    const GetFileCallback& callback,
+    FileError error) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(!callback.is_null());
+
+  if (error != FILE_ERROR_OK) {
+    callback.Run(error, base::FilePath(), scoped_ptr<ResourceEntry>());
+    return;
+  }
+
+  download_operation_->EnsureFileDownloadedByPath(
+      file_path,
+      ClientContext(USER_INITIATED),
+      GetFileContentInitializedCallback(),
+      google_apis::GetContentCallback(),
+      base::Bind(&GetFileForSavingOperation::GetFileForSavingAfterDownload,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 callback));
+}
+
+void GetFileForSavingOperation::GetFileForSavingAfterDownload(
+    const GetFileCallback& callback,
+    FileError error,
+    const base::FilePath& cache_path,
+    scoped_ptr<ResourceEntry> entry) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(!callback.is_null());
+
+  if (error != FILE_ERROR_OK) {
+    callback.Run(error, base::FilePath(), scoped_ptr<ResourceEntry>());
+    return;
+  }
+
+  const std::string& resource_id = entry->resource_id();
+  cache_->MarkDirtyOnUIThread(
+      resource_id,
+      base::Bind(&GetFileForSavingOperation::GetFileForSavingAfterMarkDirty,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 callback,
+                 cache_path,
+                 base::Passed(&entry)));
+}
+
+void GetFileForSavingOperation::GetFileForSavingAfterMarkDirty(
+    const GetFileCallback& callback,
+    const base::FilePath& cache_path,
+    scoped_ptr<ResourceEntry> entry,
+    FileError error) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(!callback.is_null());
+
+  if (error != FILE_ERROR_OK) {
+    callback.Run(error, base::FilePath(), scoped_ptr<ResourceEntry>());
+    return;
+  }
+
+  const std::string& resource_id = entry->resource_id();
+  file_write_watcher_->StartWatch(
+      cache_path,
+      resource_id,
+      base::Bind(&GetFileForSavingOperation::GetFileForSavingAfterWatch,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 callback,
+                 cache_path,
+                 base::Passed(&entry)));
+}
+
+void GetFileForSavingOperation::GetFileForSavingAfterWatch(
+    const GetFileCallback& callback,
+    const base::FilePath& cache_path,
+    scoped_ptr<ResourceEntry> entry,
+    bool success) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(!callback.is_null());
+
+  if (!success) {
+    callback.Run(FILE_ERROR_FAILED,
+                 base::FilePath(), scoped_ptr<ResourceEntry>());
+    return;
+  }
+
+  callback.Run(FILE_ERROR_OK, cache_path, entry.Pass());
+}
+
+}  // namespace file_system
+}  // namespace drive