using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using UnityEngine;

public class OldSavefileEncryption
{
    public const string BAZOOKA_MANAGER_KEY = "5de0d5798d4eb751e13b668c1fc5297d";
    public const string BAZOOKA_MANAGER_FILE_KEY = "e74af7ba21b8b4edd0e3f1d572d63c67";

    public static string DecryptRaw(byte[] data)
    {
        if (BAZOOKA_MANAGER_KEY.Trim() == string.Empty)
        {
            Debug.LogError("Failed to decrypt: Encryption/Decryption keys not present");
            return null;
        }
        try
        {
            using Aes aes = Aes.Create();
            aes.Key = Encoding.UTF8.GetBytes(BAZOOKA_MANAGER_KEY);
            aes.Mode = CipherMode.CBC;
            aes.Padding = PaddingMode.PKCS7;

            byte[] iv = new byte[16];
            Array.Copy(data, 0, iv, 0, iv.Length);
            aes.IV = iv;

            using MemoryStream ms = new(data, iv.Length, data.Length - iv.Length);
            using var cryptoStream = new CryptoStream(ms, aes.CreateDecryptor(), CryptoStreamMode.Read);
            using StreamReader reader = new(cryptoStream);

            return reader.ReadToEnd();
        }
        catch
        {
            return null;
        }
    }
}