using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Indy.IL2CPU.Assembler.X86 {
    [OpCode("jmp")]
    public class JumpToSegment: Instruction {
        public ElementReference DestinationRef {
            get;
            set;
        }

        public ushort Segment {
            get;
            set;
        }

        public override string ToString() {
            if (DestinationRef != null) {
                return "jmp " + Segment + ":" + DestinationRef.ToString();
            } else {
                return "jmp " + Segment + ":0x0";
            }
        }

        public string DestinationLabel {
            get {
                if (DestinationRef != null) {
                    return DestinationRef.Name;
                }
                return String.Empty;
            }
            set {
                DestinationRef = new ElementReference(value);
            }
        }

        public override bool IsComplete(Indy.IL2CPU.Assembler.Assembler aAssembler) {
            ulong xAddress;
            return DestinationRef == null || DestinationRef.Resolve(aAssembler, out xAddress);
        }

        public override bool DetermineSize(Indy.IL2CPU.Assembler.Assembler aAssembler, out ulong aSize) {
            aSize = 7;
            return true;
        }

        public override byte[] GetData(Indy.IL2CPU.Assembler.Assembler aAssembler) {
            var xResult = new byte[7];
            xResult[0] = 0xEA;
            ulong xAddress = 0;
            if (DestinationRef != null && DestinationRef.Resolve(aAssembler, out xAddress)) {
                xAddress = (ulong)(((long)xAddress) + DestinationRef.Offset);
            }
            Array.Copy(BitConverter.GetBytes((uint)(xAddress)), 0, xResult, 1, 4);
            Array.Copy(BitConverter.GetBytes(Segment), 0, xResult, 5, 2);
            return xResult;
        }
    }
}