using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using UnityEngine;

public static class CommandSaveUtil 
{

    private static JsonSerializerSettings getSettings()
    {
        return new JsonSerializerSettings
        {
            Formatting = Formatting.Indented,
            TypeNameHandling = TypeNameHandling.Auto,
            ReferenceLoopHandling = ReferenceLoopHandling.Ignore // Prevents circular reference issues
        };
    }

    public static bool saveLinkedList(LinkedList<CommandDTO> list, string saveFilePath)
    {
        if (list == null)
        {
            Debug.LogWarning("Cannot save null list");
            return false;
        }

        try
        {
            string json = JsonConvert.SerializeObject(list, getSettings());
            File.WriteAllText(saveFilePath, json);
            Debug.Log($"LinkedList saved successfully: {saveFilePath} ({list.Count} commands)");
            return true;
        }
        catch (Exception e)
        {
            Debug.LogError($"Failed to save LinkedList: {e.Message}");
            return false;
        }
    }

    public static LinkedList<CommandDTO> loadLinkedList(string saveFilePath)
    {
        if (!File.Exists(saveFilePath))
        {
            Debug.LogWarning($"Save file not found at: {saveFilePath}");
            return new LinkedList<CommandDTO>(); // Return empty list instead of null
        }

        try
        {
            string json = File.ReadAllText(saveFilePath);

            // Check if file is empty
            if (string.IsNullOrWhiteSpace(json))
            {
                Debug.LogWarning("Save file is empty");
                return new LinkedList<CommandDTO>();
            }

            LinkedList<CommandDTO> list = JsonConvert.DeserializeObject<LinkedList<CommandDTO>>(json, getSettings());
            Debug.Log($"LinkedList loaded successfully ({list?.Count ?? 0} commands)");
            return list ?? new LinkedList<CommandDTO>();
        }
        catch (Exception e)
        {
            Debug.LogError($"Failed to load LinkedList: {e.Message}");
            return new LinkedList<CommandDTO>(); // Return empty list on error
        }
    }

    public static void deleteSaveFile(string saveFilePath)
    {
        try
        {
            if (File.Exists(saveFilePath))
            {
                File.Delete(saveFilePath);
                Debug.Log("Save file deleted");
            }
        }
        catch (Exception e)
        {
            Debug.LogError($"Failed to delete save file: {e.Message}");
        }
    }

    public static bool hasSaveFile(string saveFilePath)
    {
        return File.Exists(saveFilePath);
    }
}