using System;

using CPUx86 = Indy.IL2CPU.Assembler.X86;

namespace Indy.IL2CPU.IL.X86 {
	[OpCode(OpCodeEnum.Stobj)]
	public class Stobj: Op {
		public Stobj(ILReader aReader, MethodInformation aMethodInfo)
			: base(aReader, aMethodInfo) {
		}
		public override void DoAssemble() {
			int xFieldSize = Assembler.StackContents.Pop().Size;
			Assembler.StackContents.Pop();
            new CPUx86.Move { DestinationReg = CPUx86.Registers.ECX, SourceReg = CPUx86.Registers.ESP, SourceIsIndirect = true, SourceDisplacement = xFieldSize };
			for (int i = 0; i < (xFieldSize / 4); i++) {
                new CPUx86.Pop { DestinationReg = CPUx86.Registers.EAX };
                new CPUx86.Move { DestinationReg = CPUx86.Registers.ECX, DestinationIsIndirect = true, DestinationDisplacement = i * 4, SourceReg = CPUx86.Registers.EAX };
			}
			switch (xFieldSize % 4) {
				case 1: {
                        new CPUx86.Pop { DestinationReg = CPUx86.Registers.EAX };
                        new CPUx86.Move { DestinationReg = CPUx86.Registers.ECX, DestinationIsIndirect = true, DestinationDisplacement = ((xFieldSize / 4) * 4), SourceReg = CPUx86.Registers.AL };
						break;
					}
				case 2: {
                        new CPUx86.Pop { DestinationReg = CPUx86.Registers.EAX };
                        new CPUx86.Move { DestinationReg = CPUx86.Registers.ECX, DestinationIsIndirect = true, DestinationDisplacement = ((xFieldSize / 4) * 4), SourceReg = CPUx86.Registers.AX };
						break;
					}
				case 0: {
						break;
					}
				default:
					throw new Exception("Remainder size " + (xFieldSize % 4) + " not supported!");
			}
            new CPUx86.Add { DestinationReg = CPUx86.Registers.ESP, SourceValue = 4 };
		}
	}
}