Support dragging a virtual file out of the browser on Linux. This is based on the discussion of drag-out feature on whatwg: http://list.whatwg.org/htdig.cgi/whatwg-whatwg.org/2009-August/022122.html

BUG=none
TEST=To test, drag an element that adds the DownloadURL format data via event.DataTransfer.setData, to the desktop or a folder.

Review URL: http://codereview.chromium.org/600154

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@39405 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 231 insertions, 72 deletions

diff --git a/chrome/browser/cocoa/web_drag_source.mm b/chrome/browser/cocoa/web_drag_source.mm
index b7818a6..1408db9 100644
--- a/chrome/browser/cocoa/web_drag_source.mm
+++ b/chrome/browser/cocoa/web_drag_source.mm
@@ -5,7 +5,6 @@
 #import "chrome/browser/cocoa/web_drag_source.h"
 
 #include "base/file_path.h"
-#include "base/file_util.h"
 #include "base/nsimage_cache_mac.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
@@ -19,7 +18,6 @@
 #include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/browser/tab_contents/tab_contents_view_mac.h"
 #include "net/base/file_stream.h"
-#include "net/base/net_errors.h"
 #include "net/base/net_util.h"
 #import "third_party/mozilla/include/NSPasteboard+Utils.h"
 #include "webkit/glue/webdropdata.h"
@@ -104,42 +102,6 @@ void PromiseWriterTask::Run() {
   // Let our destructor take care of business.
 }
 
-class PromiseFileFinalizer : public DownloadFileObserver {
- public:
-  PromiseFileFinalizer(DragDownloadFile* drag_file_downloader)
-      : drag_file_downloader_(drag_file_downloader) {
-  }
-  virtual ~PromiseFileFinalizer() { }
-
-  // DownloadFileObserver methods.
-  virtual void OnDownloadCompleted(const FilePath& file_path);
-  virtual void OnDownloadAborted();
-
- private:
-  void Cleanup();
-
-  scoped_refptr<DragDownloadFile> drag_file_downloader_;
-
-  DISALLOW_COPY_AND_ASSIGN(PromiseFileFinalizer);
-};
-
-void PromiseFileFinalizer::Cleanup() {
-  if (drag_file_downloader_.get())
-    drag_file_downloader_ = NULL;
-}
-
-void PromiseFileFinalizer::OnDownloadCompleted(const FilePath& file_path) {
-  ChromeThread::PostTask(
-      ChromeThread::UI, FROM_HERE,
-      NewRunnableMethod(this, &PromiseFileFinalizer::Cleanup));
-}
-
-void PromiseFileFinalizer::OnDownloadAborted() {
-  ChromeThread::PostTask(
-      ChromeThread::UI, FROM_HERE,
-      NewRunnableMethod(this, &PromiseFileFinalizer::Cleanup));
-}
-
 }  // namespace
 
 
@@ -310,35 +272,14 @@ void PromiseFileFinalizer::OnDownloadAborted() {
     return nil;
   }
 
-  FileStream* fileStream = new FileStream;
-  DCHECK(fileStream);
-  if (!fileStream)
-    return nil;
-
-  FilePath baseFileName = downloadFileName_.empty() ?
+  FilePath fileName = downloadFileName_.empty() ?
       GetFileNameFromDragData(*dropData_) : downloadFileName_;
-  FilePath pathName(SysNSStringToUTF8(path));
-  FilePath fileName;
-  FilePath filePath;
-  unsigned seq;
-  const unsigned kMaxSeq = 99;
-  for (seq = 0; seq <= kMaxSeq; seq++) {
-    fileName = (seq == 0) ? baseFileName :
-        baseFileName.InsertBeforeExtension(
-            std::string("-") + UintToString(seq));
-    filePath = pathName.Append(fileName);
-
-    // Explicitly (and redundantly check) for file -- despite the fact that our
-    // open won't overwrite -- just to avoid log spew.
-    if (!file_util::PathExists(filePath) &&
-        fileStream->Open(filePath,
-            base::PLATFORM_FILE_CREATE | base::PLATFORM_FILE_WRITE) == net::OK)
-      break;
-  }
-  if (seq > kMaxSeq) {
-    delete fileStream;
+  FilePath filePath(SysNSStringToUTF8(path));
+  filePath = filePath.Append(fileName);
+  FileStream* fileStream =
+      drag_download_util::CreateFileStreamForDrop(&filePath);
+  if (!fileStream)
     return nil;
-  }
 
   if (downloadURL_.is_valid()) {
     TabContents* tabContents = [contentsView_ tabContents];
@@ -352,7 +293,7 @@ void PromiseFileFinalizer::OnDownloadAborted() {
 
     // The finalizer will take care of closing and deletion.
     dragFileDownloader->Start(
-        new PromiseFileFinalizer(dragFileDownloader));
+        new drag_download_util::PromiseFileFinalizer(dragFileDownloader));
   } else {
     // The writer will take care of closing and deletion.
     g_browser_process->file_thread()->message_loop()->PostTask(FROM_HERE,
@@ -360,7 +301,7 @@ void PromiseFileFinalizer::OnDownloadAborted() {
   }
 
   // Once we've created the file, we should return the file name.
-  return SysUTF8ToNSString(fileName.value());
+  return SysUTF8ToNSString(filePath.BaseName().value());
 }
 
 @end  // @implementation WebDragSource
diff --git a/chrome/browser/download/drag_download_file.cc b/chrome/browser/download/drag_download_file.cc
index e55ccf5..8267621 100644
--- a/chrome/browser/download/drag_download_file.cc
+++ b/chrome/browser/download/drag_download_file.cc
@@ -33,7 +33,7 @@ DragDownloadFile::DragDownloadFile(
 #if defined(OS_WIN)
   DCHECK(!file_name_or_path.empty() && !file_stream.get());
   file_name_ = file_name_or_path;
-#elif defined(OS_MACOSX)
+#elif defined(OS_POSIX)
   DCHECK(!file_name_or_path.empty() && file_stream.get());
   file_path_ = file_name_or_path;
 #endif
diff --git a/chrome/browser/download/drag_download_util.cc b/chrome/browser/download/drag_download_util.cc
index ed34e70..a617d41 100644
--- a/chrome/browser/download/drag_download_util.cc
+++ b/chrome/browser/download/drag_download_util.cc
@@ -5,8 +5,17 @@
 #include "chrome/browser/download/drag_download_util.h"
 
 #include "base/string_util.h"
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/scoped_ptr.h"
+#include "base/task.h"
 #include "base/utf_string_conversions.h"
+#include "chrome/browser/chrome_thread.h"
 #include "googleurl/src/gurl.h"
+#include "net/base/file_stream.h"
+#include "net/base/net_errors.h"
+
+using net::FileStream;
 
 namespace drag_download_util {
 
@@ -45,4 +54,52 @@ bool ParseDownloadMetadata(const string16& metadata,
   return true;
 }
 
+FileStream* CreateFileStreamForDrop(FilePath* file_path) {
+  DCHECK(file_path && !file_path->empty());
+
+  scoped_ptr<FileStream> file_stream(new FileStream);
+  const int kMaxSeq = 99;
+  for (int seq = 0; seq <= kMaxSeq; seq++) {
+    FilePath new_file_path;
+    if (seq == 0) {
+      new_file_path = *file_path;
+    } else {
+ #if defined(OS_WIN)
+      std::wstring suffix = std::wstring(L"-") + IntToWString(seq);
+ #else
+      std::string suffix = std::string("-") + IntToString(seq);
+ #endif
+      new_file_path = file_path->InsertBeforeExtension(suffix);
+    }
+
+    // Explicitly (and redundantly check) for file -- despite the fact that our
+    // open won't overwrite -- just to avoid log spew.
+    if (!file_util::PathExists(new_file_path) &&
+        file_stream->Open(new_file_path, base::PLATFORM_FILE_CREATE |
+                              base::PLATFORM_FILE_WRITE) == net::OK) {
+      *file_path = new_file_path;
+      return file_stream.release();
+    }
+  }
+
+  return NULL;
+}
+
+void PromiseFileFinalizer::Cleanup() {
+  if (drag_file_downloader_.get())
+    drag_file_downloader_ = NULL;
+}
+
+void PromiseFileFinalizer::OnDownloadCompleted(const FilePath& file_path) {
+  ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
+      NewRunnableMethod(this, &PromiseFileFinalizer::Cleanup));
+}
+
+void PromiseFileFinalizer::OnDownloadAborted() {
+  ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
+      NewRunnableMethod(this, &PromiseFileFinalizer::Cleanup));
+}
+
 }  // namespace drag_download_util
diff --git a/chrome/browser/download/drag_download_util.h b/chrome/browser/download/drag_download_util.h
index 914dfda..c6f8442 100644
--- a/chrome/browser/download/drag_download_util.h
+++ b/chrome/browser/download/drag_download_util.h
@@ -5,10 +5,17 @@
 #ifndef CHROME_BROWSER_DOWNLOAD_DRAG_DOWNLOAD_UTIL_H_
 #define CHROME_BROWSER_DOWNLOAD_DRAG_DOWNLOAD_UTIL_H_
 
+#include "app/download_file_interface.h"
 #include "base/basictypes.h"
-#include "base/file_path.h"
+#include "base/ref_counted.h"
+#include "base/string16.h"
+#include "chrome/browser/download/drag_download_file.h"
 
+class FilePath;
 class GURL;
+namespace net {
+class FileStream;
+}
 
 namespace drag_download_util {
 
@@ -26,6 +33,31 @@ bool ParseDownloadMetadata(const string16& metadata,
                            FilePath* file_name,
                            GURL* url);
 
+// Create a new file at the specified path. If the file already exists, try to
+// insert the sequential unifier to produce a new file, like foo-01.txt.
+// Return a FileStream if successful.
+net::FileStream* CreateFileStreamForDrop(FilePath* file_path);
+
+// Implementation of DownloadFileObserver to finalize the download process.
+class PromiseFileFinalizer : public DownloadFileObserver {
+ public:
+  explicit PromiseFileFinalizer(DragDownloadFile* drag_file_downloader)
+      : drag_file_downloader_(drag_file_downloader) {
+  }
+  virtual ~PromiseFileFinalizer() { }
+
+  // DownloadFileObserver methods.
+  virtual void OnDownloadCompleted(const FilePath& file_path);
+  virtual void OnDownloadAborted();
+
+ private:
+  void Cleanup();
+
+  scoped_refptr<DragDownloadFile> drag_file_downloader_;
+
+  DISALLOW_COPY_AND_ASSIGN(PromiseFileFinalizer);
+};
+
 }  // namespace drag_download_util
 
 #endif  // CHROME_BROWSER_DOWNLOAD_DRAG_DOWNLOAD_UTIL_H_
diff --git a/chrome/browser/gtk/tab_contents_drag_source.cc b/chrome/browser/gtk/tab_contents_drag_source.cc
index 15b111c..22b78b2 100644
--- a/chrome/browser/gtk/tab_contents_drag_source.cc
+++ b/chrome/browser/gtk/tab_contents_drag_source.cc
@@ -5,13 +5,19 @@
 #include "chrome/browser/gtk/tab_contents_drag_source.h"
 
 #include "app/gtk_dnd_util.h"
+#include "base/file_util.h"
 #include "base/mime_util.h"
 #include "base/string_util.h"
+#include "chrome/browser/download/download_manager.h"
+#include "chrome/browser/download/drag_download_file.h"
+#include "chrome/browser/download/drag_download_util.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
 #include "chrome/browser/renderer_host/render_view_host_delegate.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/browser/tab_contents/tab_contents_view.h"
 #include "chrome/common/gtk_util.h"
+#include "net/base/file_stream.h"
+#include "net/base/net_util.h"
 #include "webkit/glue/webdropdata.h"
 
 using WebKit::WebDragOperation;
@@ -25,6 +31,8 @@ TabContentsDragSource::TabContentsDragSource(
   drag_widget_ = gtk_invisible_new();
   g_signal_connect(drag_widget_, "drag-failed",
                    G_CALLBACK(OnDragFailedThunk), this);
+  g_signal_connect(drag_widget_, "drag-begin", G_CALLBACK(OnDragBeginThunk),
+                   this);
   g_signal_connect(drag_widget_, "drag-end", G_CALLBACK(OnDragEndThunk), this);
   g_signal_connect(drag_widget_, "drag-data-get",
                    G_CALLBACK(OnDragDataGetThunk), this);
@@ -35,6 +43,8 @@ TabContentsDragSource::~TabContentsDragSource() {
   g_signal_handlers_disconnect_by_func(drag_widget_,
       reinterpret_cast<gpointer>(OnDragFailedThunk), this);
   g_signal_handlers_disconnect_by_func(drag_widget_,
+      reinterpret_cast<gpointer>(OnDragBeginThunk), this);
+  g_signal_handlers_disconnect_by_func(drag_widget_,
       reinterpret_cast<gpointer>(OnDragEndThunk), this);
   g_signal_handlers_disconnect_by_func(drag_widget_,
       reinterpret_cast<gpointer>(OnDragDataGetThunk), this);
@@ -71,6 +81,13 @@ void TabContentsDragSource::StartDragging(const WebDropData& drop_data,
     targets_mask |= GtkDndUtil::TEXT_HTML;
   if (!drop_data.file_contents.empty())
     targets_mask |= GtkDndUtil::CHROME_WEBDROP_FILE_CONTENTS;
+  if (!drop_data.download_metadata.empty() &&
+      drag_download_util::ParseDownloadMetadata(drop_data.download_metadata,
+                                                &wide_download_mime_type_,
+                                                &download_file_name_,
+                                                &download_url_)) {
+    targets_mask |= GtkDndUtil::DIRECT_SAVE_FILE;
+  }
 
   if (targets_mask == 0) {
     NOTIMPLEMENTED();
@@ -179,6 +196,64 @@ void TabContentsDragSource::OnDragDataGet(
       break;
     }
 
+    case GtkDndUtil::DIRECT_SAVE_FILE: {
+      char status_code = 'E';
+
+      // Retrieves the full file path (in file URL format) provided by the
+      // drop target by reading from the source window's XdndDirectSave0
+      // property.
+      gint file_url_len = 0;
+      guchar* file_url_value = NULL;
+      if (gdk_property_get(context->source_window,
+                           GtkDndUtil::GetAtomForTarget(
+                              GtkDndUtil::DIRECT_SAVE_FILE),
+                           GtkDndUtil::GetAtomForTarget(
+                              GtkDndUtil::TEXT_PLAIN_NO_CHARSET),
+                           0,
+                           1024,
+                           FALSE,
+                           NULL,
+                           NULL,
+                           &file_url_len,
+                           &file_url_value) &&
+          file_url_value) {
+        // Convert from the file url to the file path.
+        GURL file_url(std::string(reinterpret_cast<char*>(file_url_value),
+                                  file_url_len));
+        FilePath file_path;
+        if (net::FileURLToFilePath(file_url, &file_path)) {
+          // Open the file as a stream.
+          net::FileStream* file_stream =
+              drag_download_util::CreateFileStreamForDrop(&file_path);
+          if (file_stream) {
+              // Start downloading the file to the stream.
+              TabContents* tab_contents = tab_contents_view_->tab_contents();
+              scoped_refptr<DragDownloadFile> drag_file_downloader =
+                  new DragDownloadFile(file_path,
+                                       linked_ptr<net::FileStream>(file_stream),
+                                       download_url_,
+                                       tab_contents->GetURL(),
+                                       tab_contents->encoding(),
+                                       tab_contents);
+              drag_file_downloader->Start(
+                  new drag_download_util::PromiseFileFinalizer(
+                      drag_file_downloader));
+
+              // Set the status code to success.
+              status_code = 'S';
+          }
+        }
+
+        // Return the status code to the file manager.
+        gtk_selection_data_set(selection_data,
+                               selection_data->target,
+                               8,
+                               reinterpret_cast<guchar*>(&status_code),
+                               1);
+      }
+      break;
+    }
+
     default:
       NOTREACHED();
   }
@@ -200,9 +275,44 @@ gboolean TabContentsDragSource::OnDragFailed() {
   return FALSE;
 }
 
-void TabContentsDragSource::OnDragEnd(WebDragOperation operation) {
+void TabContentsDragSource::OnDragBegin(GdkDragContext* drag_context) {
+  if (!download_url_.is_empty()) {
+    // Generate the file name based on both mime type and proposed file name.
+    std::string download_mime_type = UTF16ToUTF8(wide_download_mime_type_);
+    std::string content_disposition("attachment; filename=");
+    content_disposition += download_file_name_.value();
+    FilePath generated_download_file_name;
+    DownloadManager::GenerateFileName(download_url_,
+                                      content_disposition,
+                                      std::string(),
+                                      download_mime_type,
+                                      &generated_download_file_name);
+
+    // Pass the file name to the drop target by setting the source window's
+    // XdndDirectSave0 property.
+    gdk_property_change(drag_context->source_window,
+                        GtkDndUtil::GetAtomForTarget(
+                            GtkDndUtil::DIRECT_SAVE_FILE),
+                        GtkDndUtil::GetAtomForTarget(
+                            GtkDndUtil::TEXT_PLAIN_NO_CHARSET),
+                        8,
+                        GDK_PROP_MODE_REPLACE,
+                        reinterpret_cast<const guchar*>(
+                            generated_download_file_name.value().c_str()),
+                        generated_download_file_name.value().length());
+  }
+}
+
+void TabContentsDragSource::OnDragEnd(GdkDragContext* drag_context,
+                                      WebDragOperation operation) {
   MessageLoopForUI::current()->RemoveObserver(this);
 
+  if (!download_url_.is_empty()) {
+    gdk_property_delete(drag_context->source_window,
+                        GtkDndUtil::GetAtomForTarget(
+                            GtkDndUtil::DIRECT_SAVE_FILE));
+  }
+
   if (!drag_failed_) {
     gfx::Point root = gtk_util::ScreenPoint(GetContentNativeView());
     gfx::Point client = gtk_util::ClientPoint(GetContentNativeView());
diff --git a/chrome/browser/gtk/tab_contents_drag_source.h b/chrome/browser/gtk/tab_contents_drag_source.h
index 8a81647..edef7ad 100644
--- a/chrome/browser/gtk/tab_contents_drag_source.h
+++ b/chrome/browser/gtk/tab_contents_drag_source.h
@@ -9,7 +9,10 @@
 
 #include "app/gfx/native_widget_types.h"
 #include "base/basictypes.h"
+#include "base/file_path.h"
 #include "base/message_loop.h"
+#include "base/string16.h"
+#include "googleurl/src/gurl.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebDragOperation.h"
 
 class TabContents;
@@ -42,13 +45,20 @@ class TabContentsDragSource : public MessageLoopForUI::Observer {
     return handler->OnDragFailed();
   }
   gboolean OnDragFailed();
+  static void OnDragBeginThunk(GtkWidget* widget,
+                             GdkDragContext* drag_context,
+                             TabContentsDragSource* handler) {
+    handler->OnDragBegin(drag_context);
+  }
+  void OnDragBegin(GdkDragContext* drag_context);
   static void OnDragEndThunk(GtkWidget* widget,
                              GdkDragContext* drag_context,
                              TabContentsDragSource* handler) {
-    handler->OnDragEnd(WebKit::WebDragOperationCopy);
+    handler->OnDragEnd(drag_context, WebKit::WebDragOperationCopy);
     // TODO(snej): Pass actual operation instead of hardcoding copy
   }
-  void OnDragEnd(WebKit::WebDragOperation operation);
+  void OnDragEnd(GdkDragContext* drag_context,
+                 WebKit::WebDragOperation operation);
   static void OnDragDataGetThunk(GtkWidget* drag_widget,
                                  GdkDragContext* context,
                                  GtkSelectionData* selection_data,
@@ -81,6 +91,15 @@ class TabContentsDragSource : public MessageLoopForUI::Observer {
   // out.
   GtkWidget* drag_widget_;
 
+  // The file mime type for a drag-out download.
+  string16 wide_download_mime_type_;
+
+  // The file name to be saved to for a drag-out download.
+  FilePath download_file_name_;
+
+  // The URL to download from for a drag-out download.
+  GURL download_url_;
+
   DISALLOW_COPY_AND_ASSIGN(TabContentsDragSource);
 };