using BaseNcoding;
using System;
using System.Security.Cryptography;
using System.Text;
using UnityEngine;
public class ManifestEntry
{
    public static byte[] CalHame(ulong checksum, ulong size, byte[] name)
    {
        if (name == null) return null;
        SHA1CryptoServiceProvider sha1 = new SHA1CryptoServiceProvider();
        byte[] allbyte = new byte[name.Length + 16];
        byte[] checksumByte = BitConverter.GetBytes(checksum);
        byte[] sizeByte = BitConverter.GetBytes(size);
        for (int i = 0; i < 16; i++)
        {
            allbyte[i] = (i < 8 ? checksumByte[7 - i] : sizeByte[15 - i]);
        }
        Buffer.BlockCopy(name, 0, allbyte, 16, name.Length);
        return sha1.ComputeHash(allbyte);
    }

    public static string CalHameString(ulong checksum, ulong size, byte[] name)
    {
        var bytes = CalHame(checksum, size, name);
        Base32 base32 = new Base32();
        return base32.Encode(bytes);
    }

    public static string CalHameString(ulong checksum, ulong size, string name)
    {
        return CalHameString(checksum, size, Encoding.UTF8.GetBytes(name));
    }
}