chrome/browser/ash/app_mode/kiosk_app_launcher.h

// 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 CHROME_BROWSER_ASH_APP_MODE_KIOSK_APP_LAUNCHER_H_
#define CHROME_BROWSER_ASH_APP_MODE_KIOSK_APP_LAUNCHER_H_

#include <optional>
#include <string>

#include "base/memory/raw_ptr.h"
#include "base/observer_list.h"
#include "base/observer_list_types.h"
#include "chrome/browser/ash/app_mode/kiosk_app_launch_error.h"

namespace ash {

// Abstract class responsible for the launch different type of kiosk apps.
//
//
// The launch flow goes like this:
// 1. Client creates KioskAppLauncher and calls Initialize() to set up
// everything.
// 2. After that, the KioskAppLauncher may emit one of the following events:
//  - OnAppPrepared()
//  - OnAppInstalling()
//  - OnLaunchFailed()
//  - InitializeNetwork(), which makes the client to be responsible to
//  initialize network and call ContinueWithNetworkReady() after that.
//
//  3. After the app is prepared, the client may want to launch the app by
//  calling LaunchApp(), which may in turn emit events:
//  - OnAppLaunched()
//  - OnAppWindowLaunched()
//  - OnLaunchFailed().
//
class KioskAppLauncher {
 public:
  class NetworkDelegate {
   public:
    virtual ~NetworkDelegate() = default;

    // Asks the client to initialize network.
    virtual void InitializeNetwork() = 0;
    // Whether the device is online.
    virtual bool IsNetworkReady() const = 0;
  };

  class Observer : public base::CheckedObserver {
   public:
    ~Observer() override = default;

    virtual void OnAppDataUpdated() {}
    virtual void OnAppInstalling() {}
    virtual void OnAppPrepared() {}
    virtual void OnAppLaunching() {}
    virtual void OnAppLaunched() {}
    virtual void OnAppWindowCreated(
        const std::optional<std::string>& app_name) {}
    virtual void OnLaunchFailed(KioskAppLaunchError::Error error) {}
  };

  class ObserverList {
   public:
    ObserverList();
    ObserverList(const ObserverList&) = delete;
    ObserverList& operator=(const ObserverList&) = delete;
    ~ObserverList();

    void AddObserver(Observer* observer);
    void RemoveObserver(Observer* observer);

    void NotifyAppDataUpdated();
    void NotifyAppInstalling();
    void NotifyAppPrepared();
    void NotifyAppLaunching();
    void NotifyAppLaunched();
    void NotifyAppWindowCreated(
        const std::optional<std::string>& app_id = std::nullopt);
    void NotifyLaunchFailed(KioskAppLaunchError::Error error);

   private:
    base::ObserverList<Observer> observers_;
  };

  KioskAppLauncher();
  explicit KioskAppLauncher(NetworkDelegate* delegate);
  KioskAppLauncher(const KioskAppLauncher&) = delete;
  KioskAppLauncher& operator=(const KioskAppLauncher&) = delete;
  virtual ~KioskAppLauncher();

  virtual void AddObserver(Observer* observer) = 0;
  virtual void RemoveObserver(Observer* observer) = 0;

  // Determine the initial configuration.
  virtual void Initialize() = 0;
  // This has to be called after launcher asked to configure network.
  virtual void ContinueWithNetworkReady() = 0;
  // Launches the kiosk app.
  virtual void LaunchApp() = 0;

 protected:
  raw_ptr<NetworkDelegate> delegate_ = nullptr;  // Not owned, owns us.
};

}  // namespace ash

#endif  // CHROME_BROWSER_ASH_APP_MODE_KIOSK_APP_LAUNCHER_H_