Implement media path filter

webkit/fileapi/media/media_path_filter.cc

Index: webkit/fileapi/media/media_path_filter.cc
diff --git a/webkit/fileapi/media/media_path_filter.cc b/webkit/fileapi/media/media_path_filter.cc
new file mode 100644
index 0000000000000000000000000000000000000000..1239f83e520d5fee4c73262922904ef0f79ee407
--- /dev/null
+++ b/webkit/fileapi/media/media_path_filter.cc
@@ -0,0 +1,51 @@
+// 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.
+
+#include "webkit/fileapi/media/media_path_filter.h"
+
+#include <algorithm>
+#include <string>
+
+#include "base/string_util.h"
+#include "net/base/mime_util.h"
+
+namespace fileapi {
+
+namespace {
+
+bool IsUnsupportedExtension(const FilePath::StringType& extension) {
+  std::string mime_type;
+  return !net::GetMimeTypeFromExtension(extension, &mime_type) ||
+      !net::IsSupportedMimeType(mime_type);
+}
+
+}  // namespace
+
+MediaPathFilter::MediaPathFilter() {
+  net::GetImageExtensions(&media_file_extensions_);
+  net::GetAudioExtensions(&media_file_extensions_);
+  net::GetVideoExtensions(&media_file_extensions_);
+
+  MediaFileExtensionList::iterator new_end =
+      std::remove_if(media_file_extensions_.begin(),
+                     media_file_extensions_.end(),
+                     &IsUnsupportedExtension);
+  media_file_extensions_.erase(new_end, media_file_extensions_.end());
+
+  for (MediaFileExtensionList::iterator itr = media_file_extensions_.begin();
+       itr != media_file_extensions_.end(); ++itr)
+    *itr = FilePath::kExtensionSeparator + *itr;
+  std::sort(media_file_extensions_.begin(), media_file_extensions_.end());
+}
+
+MediaPathFilter::~MediaPathFilter() {
+}
+
+bool MediaPathFilter::Match(const FilePath& path) const {
+  return std::binary_search(media_file_extensions_.begin(),
+                            media_file_extensions_.end(),
+                            StringToLowerASCII(path.Extension()));
+}
+
+}  // namespace fileapi