Implement ComplexFeature to support permission features with multiple rules.

chrome/common/extensions/features/complex_feature.cc

+// 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 "chrome/common/extensions/features/complex_feature.h"
+
+#include "chrome/common/extensions/features/simple_feature.h"
+
+namespace extensions {
+
+ComplexFeature::ComplexFeature(scoped_ptr<FeatureList> features) {
+  DCHECK_GT(features->size(), 0UL);
+  features_.swap(*features);
+}
+
+ComplexFeature::~ComplexFeature() {
+}
+
+Feature::Availability ComplexFeature::IsAvailableToManifest(
+    const std::string& extension_id, Extension::Type type, Location location,
+    int manifest_version, Platform platform) const {
+  Feature::Availability first_availability =
+      features_[0]->IsAvailableToManifest(
+          extension_id, type, location, manifest_version, platform);
+  if (first_availability.is_available())
+    return first_availability;
+
+  for (FeatureList::const_iterator it = features_.begin() + 1;
+       it != features_.end(); ++it) {
+    Availability availability = (*it)->IsAvailableToManifest(
+        extension_id, type, location, manifest_version, platform);
+    if (availability.is_available())
+      return availability;
+  }
+  // If none of the SimpleFeatures are available, we return the availability
+  // info of the first SimpleFeature that was not available.
+  return first_availability;
+}
+
+Feature::Availability ComplexFeature::IsAvailableToContext(
+    const Extension* extension, Context context, Platform platform) const {
+  Feature::Availability first_availability =
+      features_[0]->IsAvailableToContext(extension, context, platform);
+  if (first_availability.is_available())
+    return first_availability;
+
+  for (FeatureList::const_iterator it = features_.begin() + 1;
+       it != features_.end(); ++it) {
+    Availability availability =
+        (*it)->IsAvailableToContext(extension, context, platform);
+    if (availability.is_available())
+      return availability;
+  }
+  // If none of the SimpleFeatures are available, we return the availability
+  // info of the first SimpleFeature that was not available.
+  return first_availability;
+}
+
+std::set<Feature::Context>* ComplexFeature::GetContexts() {
+  // TODO(justinlin): Current use cases for ComplexFeatures are simple (e.g.
+  // allow API in dev channel for everyone but stable channel for a whitelist),
+  // but if they get more complicated, we need to return some meaningful context
+  // set. Either that or remove this method from the Feature interface.
+  return features_[0]->GetContexts();
+}
+
+std::string ComplexFeature::GetAvailabilityMessage(AvailabilityResult result,
+                                                   Extension::Type type) const {
+  if (result == IS_AVAILABLE)
+    return "";
+
+  // TODO(justinlin): Form some kind of combined availabilities/messages from
+  // SimpleFeatures.
+  return features_[0]->GetAvailabilityMessage(result, type);
+}
+
+}  // namespace extensions