// 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 "extensions/browser/event_router.h"

#include <string>

#include "base/bind.h"
#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/scoped_ptr.h"
#include "base/values.h"
#include "content/public/browser/notification_service.h"
#include "extensions/browser/event_listener_map.h"
#include "extensions/browser/extensions_test.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace extensions {

namespace {

// A simple mock to keep track of listener additions and removals.
class MockEventRouterObserver : public EventRouter::Observer {
 public:
  MockEventRouterObserver()
      : listener_added_count_(0),
        listener_removed_count_(0) {}
  virtual ~MockEventRouterObserver() {}

  int listener_added_count() const { return listener_added_count_; }
  int listener_removed_count() const { return listener_removed_count_; }
  const std::string& last_event_name() const { return last_event_name_; }

  void Reset() {
    listener_added_count_ = 0;
    listener_removed_count_ = 0;
    last_event_name_.clear();
  }

  // EventRouter::Observer overrides:
  void OnListenerAdded(const EventListenerInfo& details) override {
    listener_added_count_++;
    last_event_name_ = details.event_name;
  }

  void OnListenerRemoved(const EventListenerInfo& details) override {
    listener_removed_count_++;
    last_event_name_ = details.event_name;
  }

 private:
  int listener_added_count_;
  int listener_removed_count_;
  std::string last_event_name_;

  DISALLOW_COPY_AND_ASSIGN(MockEventRouterObserver);
};

typedef base::Callback<scoped_ptr<EventListener>(
    const std::string&,           // event_name
    content::RenderProcessHost*,  // process
    base::DictionaryValue*        // filter (takes ownership)
    )> EventListenerConstructor;

scoped_ptr<EventListener> CreateEventListenerForExtension(
    const std::string& extension_id,
    const std::string& event_name,
    content::RenderProcessHost* process,
    base::DictionaryValue* filter) {
  return EventListener::ForExtension(
      event_name, extension_id, process, make_scoped_ptr(filter));
}

scoped_ptr<EventListener> CreateEventListenerForURL(
    const GURL& listener_url,
    const std::string& event_name,
    content::RenderProcessHost* process,
    base::DictionaryValue* filter) {
  return EventListener::ForURL(
      event_name, listener_url, process, make_scoped_ptr(filter));
}

}  // namespace

class EventRouterTest : public ExtensionsTest {
 public:
  EventRouterTest()
      : notification_service_(content::NotificationService::Create()) {}

 protected:
  // Tests adding and removing observers from EventRouter.
  void RunEventRouterObserverTest(const EventListenerConstructor& constructor);

 private:
  scoped_ptr<content::NotificationService> notification_service_;

  DISALLOW_COPY_AND_ASSIGN(EventRouterTest);
};

TEST_F(EventRouterTest, GetBaseEventName) {
  // Normal event names are passed through unchanged.
  EXPECT_EQ("foo.onBar", EventRouter::GetBaseEventName("foo.onBar"));

  // Sub-events are converted to the part before the slash.
  EXPECT_EQ("foo.onBar", EventRouter::GetBaseEventName("foo.onBar/123"));
}

// Tests adding and removing observers from EventRouter.
void EventRouterTest::RunEventRouterObserverTest(
    const EventListenerConstructor& constructor) {
  EventRouter router(NULL, NULL);
  scoped_ptr<EventListener> listener =
      constructor.Run("event_name", NULL, new base::DictionaryValue());

  // Add/remove works without any observers.
  router.OnListenerAdded(listener.get());
  router.OnListenerRemoved(listener.get());

  // Register observers that both match and don't match the event above.
  MockEventRouterObserver matching_observer;
  router.RegisterObserver(&matching_observer, "event_name");
  MockEventRouterObserver non_matching_observer;
  router.RegisterObserver(&non_matching_observer, "other");

  // Adding a listener notifies the appropriate observers.
  router.OnListenerAdded(listener.get());
  EXPECT_EQ(1, matching_observer.listener_added_count());
  EXPECT_EQ(0, non_matching_observer.listener_added_count());

  // Removing a listener notifies the appropriate observers.
  router.OnListenerRemoved(listener.get());
  EXPECT_EQ(1, matching_observer.listener_removed_count());
  EXPECT_EQ(0, non_matching_observer.listener_removed_count());

  // Adding the listener again notifies again.
  router.OnListenerAdded(listener.get());
  EXPECT_EQ(2, matching_observer.listener_added_count());
  EXPECT_EQ(0, non_matching_observer.listener_added_count());

  // Removing the listener again notifies again.
  router.OnListenerRemoved(listener.get());
  EXPECT_EQ(2, matching_observer.listener_removed_count());
  EXPECT_EQ(0, non_matching_observer.listener_removed_count());

  // Adding a listener with a sub-event notifies the main observer with
  // proper details.
  matching_observer.Reset();
  scoped_ptr<EventListener> sub_event_listener =
      constructor.Run("event_name/1", NULL, new base::DictionaryValue());
  router.OnListenerAdded(sub_event_listener.get());
  EXPECT_EQ(1, matching_observer.listener_added_count());
  EXPECT_EQ(0, matching_observer.listener_removed_count());
  EXPECT_EQ("event_name/1", matching_observer.last_event_name());

  // Ditto for removing the listener.
  matching_observer.Reset();
  router.OnListenerRemoved(sub_event_listener.get());
  EXPECT_EQ(0, matching_observer.listener_added_count());
  EXPECT_EQ(1, matching_observer.listener_removed_count());
  EXPECT_EQ("event_name/1", matching_observer.last_event_name());
}

TEST_F(EventRouterTest, EventRouterObserverForExtensions) {
  RunEventRouterObserverTest(
      base::Bind(&CreateEventListenerForExtension, "extension_id"));
}

TEST_F(EventRouterTest, EventRouterObserverForURLs) {
  RunEventRouterObserverTest(
      base::Bind(&CreateEventListenerForURL, GURL("http://google.com/path")));
}

}  // namespace extensions