refactor (#6)

Reviewed-on: #6

Autoloads/SaveSystem.cs

@@ -1,61 +1,192 @@
+using System.Collections.Generic;
+using System.Text.Json;
 using Godot;
-using Godot.Collections;
 using Mr.BrickAdventures.scripts.Resources;
+using Mr.BrickAdventures.scripts.State;
 
 namespace Mr.BrickAdventures.Autoloads;
 
+/// <summary>
+/// Save system that serializes state to JSON using DTOs.
+/// </summary>
 public partial class SaveSystem : Node
 {
-    [Export] public string SavePath { get; set; } = "user://savegame.save";
-    [Export] public int Version { get; set; } = 1;
+    [Export] public string SavePath { get; set; } = "user://savegame.json";
+    [Export] public int Version { get; set; } = 2;
 
-    private GameManager _gameManager;
+    public static SaveSystem Instance { get; private set; }
+
+    private static readonly JsonSerializerOptions JsonOptions = new()
+    {
+        WriteIndented = true,
+        PropertyNamingPolicy = JsonNamingPolicy.CamelCase
+    };
 
     public override void _Ready()
     {
-        _gameManager = GetNode<GameManager>("/root/GameManager");
+        Instance = this;
+    }
+
+    public override void _ExitTree()
+    {
+        if (Instance == this) Instance = null;
     }
 
     public void SaveGame()
     {
-        var saveData = new Dictionary
+        var store = GameStateStore.Instance;
+        if (store == null)
         {
-            { "player_state", _gameManager.PlayerState},
-            { "version", Version}
+            GD.PrintErr("SaveSystem: GameStateStore not available.");
+            return;
+        }
+
+        // Convert to DTO (only serializable data)
+        var saveData = new SaveDataDto
+        {
+            Version = Version,
+            Coins = store.Player.Coins,
+            Lives = store.Player.Lives,
+            CurrentLevel = store.Session.CurrentLevel,
+            CompletedLevels = [.. store.Player.CompletedLevels],
+            UnlockedLevels = new List<int>(store.Player.UnlockedLevels),
+            UnlockedSkillNames = GetSkillNames(store.Player.UnlockedSkills),
+            UnlockedAchievements = new List<string>(store.Player.UnlockedAchievements),
+            Statistics = new Dictionary<string, int>(store.Player.Statistics)
         };
 
-        using var file = FileAccess.Open(SavePath, FileAccess.ModeFlags.Write);
-        file.StoreVar(saveData);
-        GD.Print("Game state saved to: ", SavePath);
+        try
+        {
+            var json = JsonSerializer.Serialize(saveData, JsonOptions);
+            using var file = FileAccess.Open(SavePath, FileAccess.ModeFlags.Write);
+            file.StoreString(json);
+            GD.Print("Game saved to: ", SavePath);
+            EventBus.EmitGameSaved();
+        }
+        catch (System.Exception e)
+        {
+            GD.PrintErr($"SaveSystem: Failed to save game: {e.Message}");
+        }
     }
 
     public bool LoadGame()
     {
         if (!FileAccess.FileExists(SavePath))
-            return false;
-
-        using var file = FileAccess.Open(SavePath, FileAccess.ModeFlags.Read);
-        var saveDataObj = (Dictionary)file.GetVar();
-
-        if (saveDataObj.ContainsKey("version") && (int)saveDataObj["version"] != Version)
         {
-            GD.Print($"Save file version mismatch. Expected: {Version}, Found: {saveDataObj["version"]}");
+            GD.Print("SaveSystem: No save file found.");
             return false;
         }
 
-        GD.Print("Game state loaded from: ", SavePath);
-        GD.Print("Player state: ", saveDataObj["player_state"]);
-        _gameManager.PlayerState = (Dictionary)saveDataObj["player_state"];
-        
-        var skills = new Array<SkillData>();
-        foreach (var skill in (Array<SkillData>)_gameManager.PlayerState["unlocked_skills"])
+        try
         {
-            skills.Add(skill);
+            using var file = FileAccess.Open(SavePath, FileAccess.ModeFlags.Read);
+            var json = file.GetAsText();
+            var saveData = JsonSerializer.Deserialize<SaveDataDto>(json, JsonOptions);
+
+            if (saveData == null)
+            {
+                GD.PrintErr("SaveSystem: Failed to deserialize save data.");
+                return false;
+            }
+
+            if (saveData.Version != Version)
+            {
+                GD.PrintErr($"SaveSystem: Version mismatch. Expected {Version}, found {saveData.Version}");
+                return false;
+            }
+
+            var store = GameStateStore.Instance;
+            if (store == null)
+            {
+                GD.PrintErr("SaveSystem: GameStateStore not available.");
+                return false;
+            }
+
+            // Apply loaded state
+            store.Player.Coins = saveData.Coins;
+            store.Player.Lives = saveData.Lives;
+            store.Session.CurrentLevel = saveData.CurrentLevel;
+
+            store.Player.CompletedLevels = saveData.CompletedLevels ?? new List<int>();
+            store.Player.UnlockedLevels = saveData.UnlockedLevels ?? new List<int> { 0 };
+            store.Player.UnlockedAchievements = saveData.UnlockedAchievements ?? new List<string>();
+            store.Player.Statistics = saveData.Statistics ?? new Dictionary<string, int>();
+
+            // Reload skills by name from SkillManager
+            store.Player.UnlockedSkills = LoadSkillsByName(saveData.UnlockedSkillNames);
+
+            GD.Print("Game loaded from: ", SavePath);
+            return true;
+        }
+        catch (System.Exception e)
+        {
+            GD.PrintErr($"SaveSystem: Failed to load game: {e.Message}");
+            return false;
         }
-        
-        _gameManager.UnlockSkills(skills);
-        return true;
     }
-    
+
+    private static List<string> GetSkillNames(List<SkillData> skills)
+    {
+        var names = new List<string>();
+        foreach (var skill in skills)
+        {
+            if (skill != null)
+                names.Add(skill.Name);
+        }
+        return names;
+    }
+
+    private List<SkillData> LoadSkillsByName(List<string> skillNames)
+    {
+        var skills = new List<SkillData>();
+        if (skillNames == null) return skills;
+
+        var skillManager = GetNodeOrNull<SkillManager>(Constants.SkillManagerPath);
+        if (skillManager == null)
+        {
+            GD.PrintErr("SaveSystem: SkillManager not available to resolve skill names.");
+            return skills;
+        }
+
+        foreach (var name in skillNames)
+        {
+            var skill = skillManager.GetSkillByName(name);
+            if (skill != null)
+            {
+                skills.Add(skill);
+            }
+            else
+            {
+                GD.PrintErr($"SaveSystem: Skill '{name}' not found in SkillManager.");
+            }
+        }
+        return skills;
+    }
+
     public bool CheckSaveExists() => FileAccess.FileExists(SavePath);
+
+    public void DeleteSave()
+    {
+        if (FileAccess.FileExists(SavePath))
+        {
+            DirAccess.RemoveAbsolute(ProjectSettings.GlobalizePath(SavePath));
+            GD.Print("Save file deleted.");
+        }
+    }
+}
+
+/// <summary>
+/// Serializable DTO for save data - no Godot types.
+/// </summary>
+public class SaveDataDto
+{
+    public int Version { get; set; }
+    public int Coins { get; set; }
+    public int Lives { get; set; }
+    public int CurrentLevel { get; set; }
+    public List<int> CompletedLevels { get; set; }
+    public List<int> UnlockedLevels { get; set; }
+    public List<string> UnlockedSkillNames { get; set; }
+    public List<string> UnlockedAchievements { get; set; }
+    public Dictionary<string, int> Statistics { get; set; }
 }