// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef IOS_CHROME_BROWSER_DEVICE_SHARING_MODEL_DEVICE_SHARING_BROWSER_AGENT_H_
#define IOS_CHROME_BROWSER_DEVICE_SHARING_MODEL_DEVICE_SHARING_BROWSER_AGENT_H_

#import "base/memory/raw_ref.h"
#import "base/scoped_observation.h"
#import "ios/chrome/browser/shared/model/browser/browser_user_data.h"
#import "ios/chrome/browser/shared/model/web_state_list/web_state_list_observer.h"
#import "ios/web/public/web_state.h"
#import "ios/web/public/web_state_observer.h"

class Browser;
class DeviceSharingManager;

// A browser agent (Brower-scoped model extension) that monitors the browser's
// web states for activations and navigations and updates the assoicated
// DeviceSharingService as the active URL changes. For browsers with incognito
// browser states, all updates clear the shared URL.
class DeviceSharingBrowserAgent
    : public BrowserUserData<DeviceSharingBrowserAgent>,
      public WebStateListObserver,
      public web::WebStateObserver {
 public:
  // Not copyable or moveable
  DeviceSharingBrowserAgent(const DeviceSharingBrowserAgent&) = delete;
  DeviceSharingBrowserAgent& operator=(const DeviceSharingBrowserAgent&) =
      delete;
  ~DeviceSharingBrowserAgent() override;

  // Tell the device sharing manager that this is the active browser.
  void UpdateForActiveBrowser();

 private:
  friend class BrowserUserData<DeviceSharingBrowserAgent>;

  explicit DeviceSharingBrowserAgent(Browser* browser,
                                     DeviceSharingManager* manager);

  // Update the active URL for the current web state of the browser.
  void UpdateForActiveWebState(web::WebState* active_web_state);

  // WebStateListObserver
  void WebStateListDidChange(WebStateList* web_state_list,
                             const WebStateListChange& change,
                             const WebStateListStatus& status) override;

  // web::WebStateObserver
  void DidFinishNavigation(web::WebState* web_state,
                           web::NavigationContext* navigation_context) override;

  // web::WebStateObserver
  void TitleWasSet(web::WebState* web_state) override;

  // DeviceSharingManager instance.
  raw_ref<DeviceSharingManager> manager_;

  // Observation of the WebStateList.
  base::ScopedObservation<WebStateList, WebStateListObserver>
      web_state_list_observation_{this};

  // Observation of the active WebState.
  base::ScopedObservation<web::WebState, web::WebStateObserver>
      active_web_state_observation_{this};
};

#endif  // IOS_CHROME_BROWSER_DEVICE_SHARING_MODEL_DEVICE_SHARING_BROWSER_AGENT_H_