using System.Collections.Generic;

namespace Obfuz.EncryptionVM.Instructions
{
    public class AddInstruction : EncryptionInstructionBase
    {
        private readonly int _addValue;
        private readonly int _opKeyIndex;

        public AddInstruction(int addValue, int opKeyIndex)
        {
            _addValue = addValue;
            _opKeyIndex = opKeyIndex;
        }
        public override int Encrypt(int value, int[] secretKey, int salt)
        {
            return (value ^ secretKey[_opKeyIndex] ^ salt) + _addValue;
        }

        public override int Decrypt(int value, int[] secretKey, int salt)
        {
            return (value - _addValue) ^ secretKey[_opKeyIndex] ^ salt;
        }

        public override void GenerateEncryptCode(List<string> lines, string indent)
        {
            lines.Add(indent + $"value = (value ^ _secretKey[{_opKeyIndex}] ^ salt) + {_addValue};");
        }

        public override void GenerateDecryptCode(List<string> lines, string indent)
        {
            lines.Add(indent + $"value = (value  - {_addValue}) ^ _secretKey[{_opKeyIndex}] ^ salt;");
        }
    }
}