using System;
using CPUx86 = Cosmos.Compiler.Assembler.X86;

namespace Cosmos.IL2CPU.X86.IL
{
	[Cosmos.IL2CPU.OpCode(ILOpCode.Code.Rem)]
	public class Rem: ILOp
	{
		public Rem(Cosmos.Compiler.Assembler.Assembler aAsmblr):base(aAsmblr)
		{
		}

    public override void Execute(MethodInfo aMethod, ILOpCode aOpCode) {

        var xStackItem = Assembler.Stack.Pop();
        var xSize = Math.Max(xStackItem.Size, Assembler.Stack.Pop().Size);
        if( xSize > 4 )
        {
            if (xStackItem.IsFloat)
            {
                new CPUx86.SSE.MoveSS { DestinationReg = CPUx86.Registers.XMM0, SourceReg = CPUx86.Registers.ESP, SourceIsIndirect = true };
                new CPUx86.Add { DestinationReg = CPUx86.Registers.ESP, SourceValue = 8 };
                new CPUx86.SSE.MoveSS { DestinationReg = CPUx86.Registers.XMM1, SourceReg = CPUx86.Registers.ESP, SourceIsIndirect = true };
                new CPUx86.SSE.XorPS { DestinationReg = CPUx86.Registers.XMM2, SourceReg = CPUx86.Registers.XMM2 };
                new CPUx86.SSE.DivPS { DestinationReg = CPUx86.Registers.XMM0, SourceReg = CPUx86.Registers.XMM1 };
                new CPUx86.SSE.MoveSS { SourceReg = CPUx86.Registers.XMM2, DestinationReg = CPUx86.Registers.ESP, DestinationIsIndirect = true };
            }
            else
            {
                new CPUx86.Pop { DestinationReg = CPUx86.Registers.ECX };
                new CPUx86.Add { DestinationReg = CPUx86.Registers.ESP, SourceValue = 4 };
                new CPUx86.Pop { DestinationReg = CPUx86.Registers.EAX }; // gets devised by ecx
                new CPUx86.Xor { DestinationReg = CPUx86.Registers.EDX, SourceReg = CPUx86.Registers.EDX };

                new CPUx86.Divide { DestinationReg = CPUx86.Registers.ECX }; // => EAX / ECX 
                new CPUx86.Push { DestinationReg = CPUx86.Registers.EDX };
            }

        }
        else
        {
            if (xStackItem.IsFloat)
            {
                new CPUx86.SSE.MoveSS { DestinationReg = CPUx86.Registers.XMM0, SourceReg = CPUx86.Registers.ESP, SourceIsIndirect = true };
                new CPUx86.Add { DestinationReg = CPUx86.Registers.ESP, SourceValue = 4 };
                new CPUx86.SSE.MoveSS { DestinationReg = CPUx86.Registers.XMM1, SourceReg = CPUx86.Registers.ESP, SourceIsIndirect = true };
                new CPUx86.Add { DestinationReg = CPUx86.Registers.ESP, SourceValue = 4 };
                new CPUx86.SSE.XorPS { DestinationReg = CPUx86.Registers.XMM2, SourceReg = CPUx86.Registers.XMM2 };
                new CPUx86.SSE.DivSS { DestinationReg = CPUx86.Registers.XMM0, SourceReg = CPUx86.Registers.XMM1 };
                new CPUx86.Sub { DestinationReg = CPUx86.Registers.ESP, SourceValue = 4 };
                new CPUx86.SSE.MoveSS { SourceReg = CPUx86.Registers.XMM2, DestinationReg = CPUx86.Registers.ESP, DestinationIsIndirect = true };
            }
            else
            {
                new CPUx86.Pop { DestinationReg = CPUx86.Registers.ECX };
                new CPUx86.Pop { DestinationReg = CPUx86.Registers.EAX }; // gets devised by ecx
                new CPUx86.Xor { DestinationReg = CPUx86.Registers.EDX, SourceReg = CPUx86.Registers.EDX };

                new CPUx86.Divide { DestinationReg = CPUx86.Registers.ECX }; // => EAX / ECX 
                new CPUx86.Push { DestinationReg = CPUx86.Registers.EDX };
            }
        }
        Assembler.Stack.Push( xStackItem );
     }
	}
}