// Copyright 2015 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.

#ifndef CHROME_BROWSER_UI_ASH_VPN_DELEGATE_CHROMEOS_H_
#define CHROME_BROWSER_UI_ASH_VPN_DELEGATE_CHROMEOS_H_

#include <vector>

#include "ash/system/chromeos/network/vpn_delegate.h"
#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "content/public/browser/notification_observer.h"
#include "content/public/browser/notification_registrar.h"
#include "extensions/browser/extension_registry_observer.h"

namespace extensions {
class ExtensionRegistry;
}

// Chrome OS implementation of a delegate that provides UI code in ash with
// access to the VPN providers enabled in the primary user's profile.
class VPNDelegateChromeOS : public ash::VPNDelegate,
                            public extensions::ExtensionRegistryObserver,
                            public content::NotificationObserver {
 public:
  VPNDelegateChromeOS();
  ~VPNDelegateChromeOS() override;

  // ash::VPNDelegate:
  bool HaveThirdPartyVPNProviders() const override;
  const std::vector<ash::VPNProvider>& GetVPNProviders() const override;
  void ShowAddPage(const ash::VPNProvider::Key& key) override;

  // extensions::ExtensionRegistryObserver:
  void OnExtensionLoaded(content::BrowserContext* browser_context,
                         const extensions::Extension* extension) override;
  void OnExtensionUnloaded(
      content::BrowserContext* browser_context,
      const extensions::Extension* extension,
      extensions::UnloadedExtensionInfo::Reason reason) override;
  void OnShutdown(extensions::ExtensionRegistry* registry) override;

  // content::NotificationObserver:
  void Observe(int type,
               const content::NotificationSource& source,
               const content::NotificationDetails& details) override;

 private:
  // Retrieves the current list of VPN providers enabled in the primary user's
  // profile and notifies observers that it has changed. Must only be called
  // when a user is logged in and the primary user's extension registry is being
  // observed.
  void UpdateVPNProviders();

  // Starts observing the primary user's extension registry to detect changes to
  // the list of VPN providers enabled in the user's profile and caches the
  // initial list. Must only be called when a user is logged in.
  void AttachToPrimaryUserExtensionRegistry();

  // The primary user's extension registry, if a user is logged in.
  extensions::ExtensionRegistry* extension_registry_ = nullptr;

  // A cache of the VPN providers enabled in the primary user's profile.
  std::vector<ash::VPNProvider> vpn_providers_;

  content::NotificationRegistrar registrar_;

  base::WeakPtrFactory<VPNDelegateChromeOS> weak_factory_;

  DISALLOW_COPY_AND_ASSIGN(VPNDelegateChromeOS);
};

#endif  // CHROME_BROWSER_UI_ASH_VPN_DELEGATE_CHROMEOS_H_