using Cryville.Common.Pdt;
using System;

namespace Cryville.Crtr {
	public abstract class PropSrc {
		int _type;
		byte[] _buf = null;
		public void Get(out int type, out byte[] value) {
			if (_buf == null) InternalGet(out _type, out _buf);
			type = _type;
			value = _buf;
		}
		protected abstract void InternalGet(out int type, out byte[] value);
		public class Arbitrary : PropSrc {
			readonly new int _type;
			readonly byte[] _value;
			public Arbitrary(int type, byte[] value) {
				_type = type;
				_value = value;
			}
			protected override void InternalGet(out int type, out byte[] value) {
				type = _type;
				value = _value;
			}
		}
		public class Boolean : PropSrc {
			readonly Func<bool> _cb;
			public Boolean(Func<bool> cb) { _cb = cb; }
			protected override void InternalGet(out int type, out byte[] value) {
				type = PdtInternalType.Number;
				value = new byte[] { _cb() ? (byte)1 : (byte)0, 0, 0, 0 };
			}
		}
		public class Float : PropSrc {
			readonly Func<float> _cb;
			public Float(Func<float> cb) { _cb = cb; }
			protected override void InternalGet(out int type, out byte[] value) {
				type = PdtInternalType.Number;
				value = BitConverter.GetBytes(_cb());
			}
		}
		public class String : PropSrc {
			readonly Func<string> _cb;
			public String(Func<string> cb) { _cb = cb; }
			protected override unsafe void InternalGet(out int type, out byte[] value) {
				type = PdtInternalType.String;
				var v = _cb();
				int strlen = v.Length;
				value = new byte[strlen * sizeof(char) + sizeof(int)];
				fixed (byte* _ptr = value) {
					char* ptr = (char*)(_ptr + sizeof(int));
					*(int*)_ptr = strlen;
					int i = 0;
					foreach (var c in v) ptr[i++] = c;
				}
			}
		}
	}
}