// SIDFX
// Copyright (C) 2004  Ian Cowburn
// 
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
//
// $Id$
//
using System;
using HardsidInterface;

namespace SIDFX
{
	/// <summary>
	/// Description of SID.	
	/// </summary>
	public class SID
	{
		[Flags]
		public enum ControlFlag
		{
			NOISE=128,
			PULSE=64,
			SAW=32,
			TRIANGLE=16,
			TEST=8,
			RING=4,
			SYNC=2,
			GATE=1,
			NONE=0
		};

		[Flags]
		public enum FilterFlag
		{
			OFF3=128,
			HP=64,
			BP=32,
			LP=16,
			EXT=8,
			V3=4,
			V2=2,
			V1=1,
			NONE=0
		};
			
		public static void Volume(byte volume)
		{
			byte v=(byte)(Hardsid.Read(24)&0xf0u);
			
			v|=volume;
			Hardsid.Write(24,v);
		}
		
		public static void Frequency(byte voice, uint val)
		{
			byte r=(byte)(voice*7);
			byte h=(byte)(val>>8);
			byte l=(byte)(val&0xff);
			
			Hardsid.Write(r,l);
			Hardsid.Write(r+1u,h);
		}
		
		public static void PulseWidth(byte voice, uint val)
		{
			byte r=(byte)(voice*7);
			byte h=(byte)(val>>8);
			byte l=(byte)(val&0xff);
			
			Hardsid.Write(r+2u,l);
			Hardsid.Write(r+3u,h);
		}
		
		public static void ADSR(byte voice,
		                        byte attack, byte decay,
		                        byte sustain, byte release)
		{
			byte r=(byte)(voice*7);
			byte ad=(byte)(((attack&0x0fu)<<4)|(decay&0x0fu));
			byte sr=(byte)(((sustain&0x0fu)<<4)|(release&0x0fu));
			
			Hardsid.Write(r+5u,ad);
			Hardsid.Write(r+6u,sr);
		}
		
		public static void Control(byte voice, ControlFlag control)
		{
			byte r=(byte)(voice*7);

			Hardsid.Write(r+4u,(uint)control);
		}
		
		public static void Cutoff(uint val)
		{
			byte h=(byte)(val>>3);
			byte l=(byte)(val&0x7);
			
			Hardsid.Write(21,l);
			Hardsid.Write(22+1u,h);
		}
		
		public static void Resonance(byte val)
		{
			byte v=(byte)(Hardsid.Read(23)&0x0fu);
			
			v|=(byte)((val&0x0fu)<<4);
			Hardsid.Write(23,v);
		}
		
		public static void Filter(FilterFlag flags)
		{
			byte h=(byte)((uint)flags&0xf0u);
			byte l=(byte)((uint)flags&0x0fu);

			byte v=(byte)(Hardsid.Read(23)&0xf0u);
			
			v|=l;
			Hardsid.Write(23,v);

			v=(byte)(Hardsid.Read(24)&0x0fu);
			
			v|=h;
			Hardsid.Write(24,v);
		}
		
		private SID() {}
	}
}