using System;

namespace func.brainfuck
{
    public class BrainfuckBasicCommands
    {
        public static void RegisterTo(IVirtualMachine vm, Func<int> read, Action<char> write)
        {
            var characters = "QWERTYUIOPASDFGHJKLZXCVBNMqwertyuiopasdfghjklzxcvbnm1234567890";

            vm.RegisterCommand('.', b => { write((char)b.Memory[b.MemoryPointer]); });
            vm.RegisterCommand('+', b =>
            {
                b.Memory[b.MemoryPointer] = (byte)((b.Memory[b.MemoryPointer] + 1) % 256);
                //b.Memory[b.MemoryPointer] = (byte)(b.Memory[b.MemoryPointer] << 31 + 1);
            });
            vm.RegisterCommand('-', b =>
            {
                b.Memory[b.MemoryPointer] = (byte)((b.Memory[b.MemoryPointer] + 255) % 256);
            });
            vm.RegisterCommand(',', b =>
            {
                b.Memory[b.MemoryPointer] = (byte)read();
            });
            vm.RegisterCommand('>', b =>
            {
                b.MemoryPointer = (b.MemoryPointer + 1) % b.Memory.Length;
            });
            vm.RegisterCommand('<', b =>
            {
                b.MemoryPointer =  (b.MemoryPointer + b.Memory.Length - 1) % b.Memory.Length;
            });

            foreach (var item in characters)
            {
                vm.RegisterCommand(item, b => { b.Memory[b.MemoryPointer] = (byte)item; });
            }
        }
    }
}