fix: save system

Assets/Scripts/DataPersistence.meta

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Assets/Scripts/DataPersistence/Data.meta

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Assets/Scripts/DataPersistence/Data/GameData.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+[System.Serializable]
+public class GameData
+{
+    public int currentLevel;
+    public Vector3 playerPosition;
+
+    // from PlayerHealth.cs
+    public int currentHealth;
+    public bool godMode;
+
+    // from PlayerMovement.cs
+    public float speed;
+    public bool isDoubleSpeed;
+
+    // from PlayerShooting.cs
+    public int damagePerShot;
+    public bool isOneHitKill;
+
+    // from PlayerGold.cs
+    public int currentGold;
+    public bool isMotherlode;
+
+    public List<PetData> pet = new List<PetData>();
+
+
+    // the values defined in this constructor will be the default values
+    // the game starts with when there's no data to load
+    public GameData()
+    {
+
+    }
+}
+
+[System.Serializable]
+public class PetData
+{
+    public string type;
+    public int currentHealth;
+    public int damagePerShot;
+    public float speed;
+}
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Assets/Scripts/DataPersistence/Data/GameData.cs.meta

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Assets/Scripts/DataPersistence/DataPersistenceManager.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using System.Linq;
+
+public class DataPersistenceManager : MonoBehaviour
+{
+    [Header("File Storage Config")]
+    [SerializeField] private string fileName;
+
+    private GameData gameData;
+    private List<IDataPersistence> dataPersistenceObjects;
+    private FileDataHandler dataHandler;
+
+    public static DataPersistenceManager instance { get; private set; }
+
+    private void Awake()
+    {
+        if (instance != null)
+        {
+            Debug.LogError("Found more than one Data Persistence Manager in the scene.")
+        };
+        instance = this;
+    }
+
+    private void Start()
+    {
+        this.dataHandler = new FileDataHandler(Application.persistentDataPath, fileName);
+        this.dataPersistenceObjects = FindAllDataPersistenceObjects();
+        LoadGame();
+    }
+
+    public void NewGame()
+    {
+        this.gameData = new GameData();
+    }
+
+    public void LoadGame()
+    {
+        // load any saved data from a file using data handler
+        this.gameData = dataHandler.Load();
+
+        // if no data can be loaded, initialize to a new game
+        if (this.gameData == null)
+        {
+            Debug.Log("Mo data was found. Initializing data to defaults");
+            NewGame();
+        }
+        // push the loaded data to all other scripts that need it
+        foreach (IDataPersistence dataPersistenceObj in dataPersistenceObjects) 
+        {
+            dataPersistenceObj.LoadData(gameData);
+        }
+        Debug.Log("Loaded game data");
+    }
+
+    public void SaveGame()
+    {
+        // pass the data to other scripts so they can update it
+        foreach (IDataPersistence dataPersistenceObj in dataPersistenceObjects)
+        {
+            dataPersistenceObj.SaveData(ref gameData);
+        }
+        Debug.Log("Saved game data");
+
+        // save that data to a file using data handler
+        dataHandler.Save(gameData);
+    }
+
+    private void OnApplicationQuit()
+    {
+        SaveGame();
+    }
+
+    private List<IDataPersistence> FindAllDataPersistenceObjects()
+    {
+        IEnumerable<IDataPersistence> dataPersistenceObjects = FindObjectsOfType<MonoBehaviour>().OfType<IDataPersistence>();
+        return new List<IDataPersistence>(dataPersistenceObjects);
+    }
+}

Assets/Scripts/DataPersistence/DataPersistenceManager.cs.meta

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Assets/Scripts/DataPersistence/FileDataHandler.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using System;
+using System.IO;
+
+public class FileDataHandler
+{
+    private string dataDirPath = "";
+    private string dataFileName = "";
+
+    public FileDataHandler(string dataDirPath, string dataFileName)
+    {
+        this.dataDirPath = dataDirPath;
+        this.dataFileName = dataFileName;
+    }
+
+    public GameData Load()
+    {
+        // use Path.combine to account for different OS's having different path separators
+        string fullPath = Path.Combine(dataDirPath, dataFileName);
+        GameData loadedData = null;
+        if (File.Exists(fullPath))
+        {
+            try
+            {
+                // load the serialized data from the file
+                string dataToLoad = "";
+                using (FileStream stream = new FileStream(fullPath, FileMode.Open))
+                {
+                    using (StreamReader reader = new StreamReader(stream))
+                    {
+                        dataToLoad = reader.ReadToEnd();
+                    }
+                }
+
+                //deserialize the data from Json back into the C# object
+                loadedData = JsonUtility.FromJson<GameData>(dataToLoad);
+            }
+            catch (Exception e)
+            {
+                Debug.LogError("Error occured when trying to load data to file: " + fullPath + "\n" + e);
+            }
+        }
+    }
+
+    public void Save(GameData data)
+    {
+        // use Path.combine to account for different OS's having different path separators
+        string fullPath = Path.Combine(dataDirPath, dataFileName);
+        try
+        {
+            // create the directory the file will be written to if it doesn't already exist
+            Directory.CreateDirectory(Path.GetDirectoryName(fullPath));
+
+            //serialize the C# game data object into Json
+            string dataToStore = JsonUtility.ToJson(data, true);
+
+            // write the serialized data to the file
+            using (FileStream stream = new FileStream(fullPath, FileMode.Create))
+            {
+                using (StreamWriter writer = new StreamWriter(stream)) 
+                {
+                    writer.Write(dataToStore);
+                }
+            }
+        }
+        catch (Exception e)
+        {
+            Debug.LogError("Error occured when trying to save data to file: " + fullPath + "\n" + e);
+        }
+    }
+}

Assets/Scripts/DataPersistence/FileDataHandler.cs.meta

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Assets/Scripts/DataPersistence/IDataPersistence.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public interface IDataPersistence
+{
+    void LoadData(GameData data);
+    void SaveData(ref GameData data);
+}

Assets/Scripts/DataPersistence/IDataPersistence.cs.meta

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Assets/Scripts/SaveData.cs

+/*
 using static UnityEditor.Progress;
 using System.Collections.Generic;
 using System;
@@ -60,3 +61,4 @@ public class PetData
     public int damagePerShot;
     public float speed;
 }
+*/
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