using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.IO;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
using System.Runtime.CompilerServices;
using Microsoft.CSharp.RuntimeBinder;
using NIFLib.Enums;
using NIFLib.Nodes;
using Binder = Microsoft.CSharp.RuntimeBinder.Binder;

namespace NIFLib.Core
{
    public class NiFile : IDisposable
    {
        private readonly BinaryReader _reader;

        [CompilerGenerated]
        [SuppressMessage("ReSharper", "InconsistentNaming")]
        private static class O__11
        {
            /// <summary>
            /// The P__0
            /// </summary>
            public static CallSite<Action<CallSite, object, NiFile>> p__0;
        
            /// <summary>
            /// The P__1
            /// </summary>
            public static CallSite<Func<CallSite, object, object>> p__1;
        
            /// <summary>
            /// The P__2
            /// </summary>
            public static CallSite<Func<CallSite, object, bool>> p__2;
        
            /// <summary>
            /// The P__3
            /// </summary>
            public static CallSite<Func<CallSite, object, object>> p__3;
        
            /// <summary>
            /// The P__4
            /// </summary>
            public static CallSite<Func<CallSite, object, object, object>> p__4;
        
            /// <summary>
            /// The P__5
            /// </summary>
            public static CallSite<Func<CallSite, object, bool>> p__5;
        
            /// <summary>
            /// The P__6
            /// </summary>
            public static CallSite<Action<CallSite, object, NiFile>> p__6;
        }

        public const uint InvalidRef = 4294967295u;
        public const string CmdTopLevelObject = "Top Level Object";
        public const string CmdEndOfFile = "End Of File";

        public NiHeader Header;
        public NiFooter Footer;
        public readonly Dictionary<uint, NiObject> ObjectsByRef = new Dictionary<uint, NiObject>();
        public NifVersion Version => Header.Version;

        public NiFile(string filePath) : this(new BinaryReader(File.OpenRead(filePath))) { }



        public NiFile(BinaryReader reader)
        {
            _reader = reader;
            Header = new NiHeader(this, reader);
            ReadNiObjects();
            Footer = new NiFooter(this, reader);
            FixRefs();
        }
        
        private void ReadNiObjects()
        {
            var num = 0;
            string text;
            while (true)
            {
                if (Version >= NifVersion.VER_5_0_0_1)
                {
                    if (Version <= NifVersion.VER_10_1_0_106 && _reader.ReadUInt32() != 0u)
                    {
                        break;
                    }
                    text = Header.BlockTypes[Header.BlockTypeIndex[num]].Value;
                }
                else
                {
                    var num2 = _reader.ReadUInt32();
                    if (num2 > 30u || num2 < 6u)
                    {
                        goto IL_74;
                    }
                    text = new string(_reader.ReadChars((int)num2));
                    if (Header.Version < NifVersion.VER_3_3_0_13)
                    {
                        switch (text)
                        {
                            case "Top Level Object":
                                continue;
                            case "End Of File":
                                return;
                        }
                    }
                }
                uint key;
                if (Version < NifVersion.VER_3_3_0_13)
                {
                    key = _reader.ReadUInt32();
                }
                else
                {
                    key = (uint)num;
                }
                var exprE7 = Type.GetType("Niflib." + text);
                if (exprE7 == null)
                {
                    goto Block_8;
                }
                var value = (NiObject)Activator.CreateInstance(exprE7, this, _reader);
                ObjectsByRef.Add(key, value);
                if (Version < NifVersion.VER_3_3_0_13) continue;
                num++;
                if (num >= Header.NumBlocks)
                {
                    return;
                }
            }
            throw new Exception("Check value is not zero! Invalid file?");
        IL_74:
            throw new Exception("Invalid object type string length!");
        Block_8:
            throw new NotImplementedException(text);
        }

        
        private void FixRefs()
        {
            // Fix Object Refs
            foreach (var current in ObjectsByRef.Values)
            {
                FixRefs(current);
            }

            // Fix Footer Refs
            foreach (var niRef in Footer.RootNodes)
            {
                niRef.SetRef(this);
            }
        }

        
        [SuppressMessage("ReSharper", "InconsistentNaming")]
        private void FixRefs(object obj)
        {
            var fields = obj.GetType().GetFields();
            foreach (var fieldInfo in fields)
            {
                if (fieldInfo.FieldType.Name.Contains("NiRef"))
                {
                    if (fieldInfo.FieldType.IsArray)
                    {
                        var enumerable = (IEnumerable)fieldInfo.GetValue(obj);
                        if (enumerable == null)
                        {
                            goto IL_303;
                        }
                        var enumerator = enumerable.GetEnumerator();
                        try
                        {
                            while (enumerator.MoveNext())
                            {
                                var current = enumerator.Current;
                                if (O__11.p__0 == null)
                                {
                                    O__11.p__0 = CallSite<Action<CallSite, object, NiFile>>.Create(Binder.InvokeMember(CSharpBinderFlags.ResultDiscarded, "SetRef", null, typeof(NiFile), new[]
                                    {
                                        CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null),
                                        CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.UseCompileTimeType, null)
                                    }));
                                }
                                O__11.p__0.Target(O__11.p__0, current, this);
                                if (fieldInfo.Name == "Children")
                                {
                                    if (O__11.p__2 == null)
                                    {
                                        O__11.p__2 = CallSite<Func<CallSite, object, bool>>.Create(Binder.UnaryOperation(CSharpBinderFlags.None, ExpressionType.IsTrue, typeof(NiFile), new[]
                                        {
                                            CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null)
                                        }));
                                    }
                                    var arg_16A_0 = O__11.p__2.Target;
                                    CallSite arg_16A_1 = O__11.p__2;
                                    if (O__11.p__1 == null)
                                    {
                                        O__11.p__1 = CallSite<Func<CallSite, object, object>>.Create(Binder.InvokeMember(CSharpBinderFlags.None, "IsValid", null, typeof(NiFile), new[]
                                        {
                                            CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null)
                                        }));
                                    }
                                    if (arg_16A_0(arg_16A_1, O__11.p__1.Target(O__11.p__1, current)))
                                    {
                                        if (O__11.p__3 == null)
                                        {
                                            O__11.p__3 = CallSite<Func<CallSite, object, object>>.Create(Binder.GetMember(CSharpBinderFlags.None, "Object", typeof(NiFile), new[]
                                            {
                                                CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null)
                                            }));
                                        }
                                        if (!(O__11.p__3.Target(O__11.p__3, current) is NiAVObject expr_1C2))
                                        {
                                            throw new Exception("no child");
                                        }
                                        expr_1C2.Parent = (NiNode)obj;
                                    }
                                }
                            }
                            goto IL_303;
                        }
                        finally
                        {
                            if (enumerator is IDisposable disposable)
                            {
                                disposable.Dispose();
                            }
                        }
                    }
                    var value = fieldInfo.GetValue(obj);
                    if (O__11.p__5 == null)
                    {
                        O__11.p__5 = CallSite<Func<CallSite, object, bool>>.Create(Binder.UnaryOperation(CSharpBinderFlags.None, ExpressionType.IsTrue, typeof(NiFile), new[]
                        {
                            CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null)
                        }));
                    }
                    var arg_2A0_0 = O__11.p__5.Target;
                    CallSite arg_2A0_1 = O__11.p__5;
                    if (O__11.p__4 == null)
                    {
                        O__11.p__4 = CallSite<Func<CallSite, object, object, object>>.Create(Binder.BinaryOperation(CSharpBinderFlags.None, ExpressionType.Equal, typeof(NiFile), new[]
                        {
                            CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null),
                            CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.Constant, null)
                        }));
                    }
                    if (!arg_2A0_0(arg_2A0_1, O__11.p__4.Target(O__11.p__4, value, null)))
                    {
                        if (O__11.p__6 == null)
                        {
                            O__11.p__6 = CallSite<Action<CallSite, object, NiFile>>.Create(Binder.InvokeMember(CSharpBinderFlags.ResultDiscarded, "SetRef", null, typeof(NiFile), new[]
                            {
                                CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null),
                                CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.UseCompileTimeType, null)
                            }));
                        }
                        O__11.p__6.Target(O__11.p__6, value, this);
                    }
                }
                IL_303:;
            }
        }
        

        public NiAVObject FindRoot()
        {
            var niAvObject = (from obj in ObjectsByRef.Values.OfType<NiAVObject>()
                select obj).FirstOrDefault();
            if (niAvObject == null)
            {
                return null;
            }
            while (niAvObject.Parent != null)
            {
                niAvObject = niAvObject.Parent;
            }
            return niAvObject;
        }

        public void PrintNifTree()
        {
            var niAvObject = FindRoot();
            if (niAvObject == null)
            {
                Console.WriteLine("No Root!");
                return;
            }
            const int depth = 0;
            PrintNifNode(niAvObject, depth);
        }

        private static void PrintNifNode(NiObjectNET root, int depth)
        {
            var text = string.Empty;
            for (var i = 0; i < depth; i++)
            {
                text += "*";
            }
            text += " ";
            Console.WriteLine(text + " " + root.Name);
            if (!(root is NiNode niNode)) return;

            var children = niNode.Children;
            foreach (var niRef in children)
            {
                if (niRef.IsValid())
                {
                    PrintNifNode(niRef.Object, depth + 1);
                }
            }
        }

        public void Dispose()
        {
            _reader?.Dispose();
        }
    }
}