using System;
using System.Linq;
using Indy.IL2CPU.Assembler;
using Indy.IL2CPU.Assembler.X86;
using CPUx86 = Indy.IL2CPU.Assembler.X86;
using Indy.IL2CPU.Compiler;

namespace Indy.IL2CPU.IL.X86
{
    public class X86MethodFooterOp : MethodFooterOp
    {
        public readonly uint TotalArgsSize = 0;
        public readonly uint ReturnSize = 0;
        public readonly MethodInformation.Variable[] Locals;
        public readonly MethodInformation.Argument[] Args;
        public readonly bool DebugMode;
        public readonly bool MethodIsNonDebuggable;
        public readonly int LocAllocItemCount;

        public X86MethodFooterOp(ILReader aReader, MethodInformation aMethodInfo)
            : base(aReader, aMethodInfo)
        {
            if (aMethodInfo != null)
            {
                //			if (aMethodInfo.Locals.Length > 0) {
                //				TotalLocalsSize += aMethodInfo.Locals[aMethodInfo.Locals.Length - 1].Offset + aMethodInfo.Locals[aMethodInfo.Locals.Length - 1].Size;
                //			}
                Locals = aMethodInfo.Locals.ToArray();
                Args = aMethodInfo.Arguments.ToArray();
                ReturnSize = aMethodInfo.ReturnSize;
                DebugMode = aMethodInfo.DebugMode;
                MethodIsNonDebuggable = aMethodInfo.IsNonDebuggable;
                LocAllocItemCount = 0;
                //if (aMethodInfo.MethodData.ContainsKey(Localloc.LocAllocCountMethodDataEntry)) {
                //    LocAllocItemCount = (int)aMethodInfo.MethodData[Localloc.LocAllocCountMethodDataEntry];
                //}
            }
        }

        public override void DoAssemble()
        {
            //uint xArgSize = 0;
            //foreach (var xItem in Args) {
            //    xArgSize += xItem.Size;
            //}
            //var xDecRefInfo = GetService<IMetaDataInfoService>().GetMethodInfo(GCImplementationRefs.DecRefCountRef,
            //                                                                   false);
            //var xHeapFreeInfo =
            //    GetService<IMetaDataInfoService>().GetMethodInfo(typeof (RuntimeEngine).GetMethod("Heap_Free"), false);
            //AssembleFooter(ReturnSize, Assembler, Locals, Args, xArgSize, DebugMode, MethodIsNonDebuggable,
            //               (uint) LocAllocItemCount, GetService<IMetaDataInfoService>().SizeOfType,
            //               xDecRefInfo.LabelName, xHeapFreeInfo.LabelName);
        }

        public static void AssembleFooter(uint aReturnSize, Assembler.Assembler aAssembler, MethodInformation.Variable[] aLocals, MethodInformation.Argument[] aArgs, uint aTotalArgsSize, bool aDebugMode, bool aIsNonDebuggable, uint aLocAllocItemCount, Func<Type, uint> aGetStorageSizeDelegate, string aDecRefLabel, string aHeapFreeLabel)
        {
            //uint xReturnSize = aReturnSize;
            //if (xReturnSize % 4 > 0)
            //{
            //    xReturnSize += 4 - xReturnSize % 4;
            //}
            //new Label(EndOfMethodLabelNameNormal);
            //new CPUx86.Move { DestinationReg = CPUx86.Registers.ECX, SourceValue = 0 };
            //if (aReturnSize > 0)
            //{
            //    //var xArgSize = (from item in aArgs
            //    //                let xSize = item.Size + item.Offset
            //    //                select xSize).FirstOrDefault();
            //    //new Comment(String.Format("ReturnSize = {0}, ArgumentSize = {1}",
            //    //                          aReturnSize,
            //    //                          xArgSize));
            //    //int xOffset = 4;
            //    //if(xArgSize>0) {
            //    //    xArgSize -= xReturnSize;
            //    //    xOffset = xArgSize;
            //    //}
            //    int xOffset = 4;
            //    if (aArgs.Length > 0)
            //    {
            //        // old code:
            //        //xOffset = aArgs.First().Offset + 4;
            //        //if (xOffset < 0)
            //        //{
            //        //    xOffset = 0;
            //        //}

            //        // new code:
            //        xOffset = (int)((from item in aArgs
            //                   select item.Offset + item.Size).First());
            //    }
            //    for (int i = 0; i < xReturnSize / 4; i++)
            //    {
            //        new CPUx86.Pop { DestinationReg = CPUx86.Registers.EAX }; 
            //        new CPUx86.Move {
            //            DestinationReg = CPUx86.Registers.EBP,
            //            DestinationIsIndirect = true,
            //            DestinationDisplacement = (int)(xOffset + ((i + 1) * 4) + 4 - xReturnSize),
            //            SourceReg = Registers.EAX
            //        };
            //    }
            //}
            //new CPUx86.Jump { DestinationLabel = EndOfMethodLabelNameException };
            //new Label(EndOfMethodLabelNameException);
            //for (int i = 0; i < aLocAllocItemCount;i++ )
            //{
            //    new CPUx86.Call { DestinationLabel = aHeapFreeLabel };
            //}
            //if (aDebugMode && aIsNonDebuggable)
            //{
            //    new CPUx86.Call { DestinationLabel = "DebugPoint_DebugResume" };
            //}
            
            //if ((from xLocal in aLocals
            //     where xLocal.IsReferenceType
            //     select 1).Count() > 0 || (from xArg in aArgs
            //                               where xArg.IsReferenceType
            //                               select 1).Count() > 0) {
            //    new CPUx86.Push { DestinationReg = Registers.ECX };
            //    foreach (MethodInformation.Variable xLocal in aLocals) {
            //        if (xLocal.IsReferenceType) {
            //            Op.Ldloc(aAssembler,
            //                     xLocal,
            //                     false,
            //                     aGetStorageSizeDelegate(xLocal.VariableType));
            //            new CPUx86.Call { DestinationLabel = aDecRefLabel };
            //        }
            //    }
            //    foreach (MethodInformation.Argument xArg in aArgs) {
            //        if (xArg.IsReferenceType) {
            //            Op.Ldarg(aAssembler,
            //                     xArg,
            //                     false);
            //            //,                                 aGetStorageSizeDelegate(xArg.ArgumentType)
            //            new CPUx86.Call { DestinationLabel = aDecRefLabel };
            //        }
            //    }
            //    new CPUx86.Pop { DestinationReg = CPUx86.Registers.ECX };
            //}
            //for (int j = aLocals.Length - 1; j >= 0; j--)
            //{
            //    int xLocalSize = aLocals[j].Size;
            //    new CPUx86.Add { DestinationReg = CPUx86.Registers.ESP, SourceValue = (uint)xLocalSize };
            //}
            ////new CPUx86.Add(CPUx86.Registers_Old.ESP, "0x4");
            //new CPUx86.Pop { DestinationReg = CPUx86.Registers.EBP };
            //var xRetSize = ((int)aTotalArgsSize) - ((int)xReturnSize);
            //if(xRetSize<0) {
            //    xRetSize = 0;
            //}
            //new CPUx86.Return { DestinationValue = (uint)xRetSize };
        }
    }
}