using System.Collections;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
using UnityEngine.SceneManagement;

public class DataPersistenceManager : MonoBehaviour
{
    // [Header("Debugging")]
    // [SerializeField] private bool initializeDataIfNull = false;

    [Header("File Storage Config")]
    [SerializeField]
    private string fileName;

    [SerializeField]
    private bool useEncryption;

    [Header("Auto Saving Configuration")]
    [SerializeField]
    private float autoSaveTimeSeconds = 60f;

    private GameData gameData = new GameData();
    private List<IDataPersistence<GameData>> dataPersistenceObjects;
    private FileDataHandler dataHandler;

    private Coroutine autoSaveCoroutine;

    public static DataPersistenceManager instance { get; private set; }

    private void Awake()
    {
        if (instance != null)
        {
            Debug.Log(
                "Found more than one Data Persistence Manager in the scene. Destroying the newest one."
            );
            Destroy(this.gameObject);
            return;
        }
        instance = this;
        DontDestroyOnLoad(this.gameObject);

        this.dataHandler = new FileDataHandler(
            Application.persistentDataPath,
            fileName,
            useEncryption
        );
    }

    private void OnEnable()
    {
        SceneManager.sceneLoaded += OnSceneLoaded;

        Initialize();
    }

    private void OnDisable()
    {
        SceneManager.sceneLoaded -= OnSceneLoaded;
    }

    public void OnSceneLoaded(Scene scene, LoadSceneMode mode)
    {
        // Start();
    }

    private void Initialize()
    {
        LoadGame();

        // start up the auto saving coroutine
        if (autoSaveCoroutine != null)
        {
            StopCoroutine(autoSaveCoroutine);
        }
        autoSaveCoroutine = StartCoroutine(AutoSave());
    }

    public void NewGame()
    {
        Debug.Log("new game");
        this.gameData = new GameData();
    }

    public void LoadGame()
    {
        Debug.Log("Loading game");

        this.dataPersistenceObjects = FindAllDataPersistenceObjects();

        // load any saved data from a file using the data handler
        this.gameData = dataHandler.Load();

        // start a new game if the data is null and we're configured to initialize data for debugging purposes
        if (this.gameData == null)
        {
            NewGame();
            return;
        }

        // if no data can be loaded, don't continue
        // if (this.gameData == null)
        // {
        //     Debug.Log("No data was found. A New Game needs to be started before data can be loaded.");
        //     return;
        // }

        // push the loaded data to all other scripts that need it
        foreach (IDataPersistence<GameData> dataPersistenceObj in dataPersistenceObjects)
        {
            dataPersistenceObj.LoadData(gameData);
        }
    }

    public void SaveGame()
    {
        Debug.Log("Saving game");

        this.dataPersistenceObjects = FindAllDataPersistenceObjects();

        // if we don't have any data to save, log a warning here
        if (this.gameData == null)
        {
            Debug.LogWarning(
                "No data was found. A New Game needs to be started before data can be saved."
            );
            return;
        }

        // pass the data to other scripts so they can update it
        foreach (IDataPersistence<GameData> dataPersistenceObj in dataPersistenceObjects)
        {
            dataPersistenceObj.SaveData(gameData);
        }

        // timestamp the data so we know when it was last saved
        gameData.lastUpdated = System.DateTime.Now.ToBinary();

        // save that data to a file using the data handler
        dataHandler.Save(gameData);
    }

    private void OnApplicationQuit()
    {
        SaveGame();
    }

    private List<IDataPersistence<GameData>> FindAllDataPersistenceObjects()
    {
        // FindObjectsofType takes in an optional boolean to include inactive gameobjects
        IEnumerable<IDataPersistence<GameData>> dataPersistenceObjects =
            FindObjectsByType<MonoBehaviour>(FindObjectsSortMode.None)
                .OfType<IDataPersistence<GameData>>();

        var list = new List<IDataPersistence<GameData>>(dataPersistenceObjects);
        return list;
    }

    private IEnumerator AutoSave()
    {
        while (true)
        {
            yield return new WaitForSeconds(autoSaveTimeSeconds);
            SaveGame();
            Debug.Log("Auto Saved Game");
        }
    }
}