using MsgPack;
using System.IO;
using System;
using System.Collections;
using System.Collections.Generic;
using CodeStage.AntiCheat.ObscuredTypes;

namespace metagen {

//NOTE: don't change existing values
public enum MetaIoError
{
  NONE                   = 0,
  NO_SPACE_LEFT_IN_ARRAY = 1,
  HAS_LEFT_SPACE         = 2,
  ARRAY_STACK_IS_EMPTY   = 3,
  FAIL_READ              = 4,
  TYPE_DONT_MATCH        = 5,
  DATA_MISSING           = 7,
  GENERIC                = 10,
}

public class MetaException : Exception
{
  public MetaIoError err;

  public MetaException(MetaIoError err)
  {
    this.err = err;
  }
}

[System.Flags]
public enum MetaSyncContextOpts
{
  NONE     = 0,
  USE_MASK = 1
}

[System.Flags]
public enum MetaSyncFieldOpts
{
  NONE               = 0,
  SKIP_NOT_IN_MASK   = 1,
  SKIP_OPTIONAL      = 2
}

public struct MetaSyncContext
{
  public bool is_read;
  public IDataReader reader;
  public IDataWriter writer;
  public Func<uint, IMetaStruct> factory;
  public MetaSyncContextOpts opts;

  public bool CanReadField(MetaSyncFieldOpts opts)
  {
    return is_read && (opts & MetaSyncFieldOpts.SKIP_NOT_IN_MASK) != MetaSyncFieldOpts.SKIP_NOT_IN_MASK;
  }

  public bool CanWriteField(MetaSyncFieldOpts opts)
  {
    return !is_read && (opts & MetaSyncFieldOpts.SKIP_NOT_IN_MASK) != MetaSyncFieldOpts.SKIP_NOT_IN_MASK;
  }

  public bool IsMaskUsed() 
  {
    return (opts & MetaSyncContextOpts.USE_MASK) > 0;
  }

  public static MetaSyncContext NewForRead(Func<uint, IMetaStruct> factory, IDataReader reader, MetaSyncContextOpts opts = 0)
  {
    var ctx = new MetaSyncContext() {
      is_read = true,
      reader = reader,
      writer = null,
      factory = factory,
      opts = opts
    };
    return ctx;
  }

  public static MetaSyncContext NewForWrite(IDataWriter writer, MetaSyncContextOpts opts = 0)
  {
    var ctx = new MetaSyncContext() {
      is_read = false,
      reader = null,
      writer = writer,
      opts = opts
    };
    return ctx;
  }
}

public interface IMetaStruct 
{
  uint CLASS_ID();

  int getFieldsCount();
  int getWritableFieldsCount();

  void syncFields(MetaSyncContext ctx);

  void reset();
}

public interface IMetaCloneable
{
  void copy(IMetaStruct source);
  IMetaStruct clone();
}

public abstract class BaseMetaStruct : IMetaStruct
{
  public virtual uint CLASS_ID() { return 0; }

  public virtual int getFieldsCount() { return 0; }
  public virtual int getWritableFieldsCount() { return 0; }

  public virtual void reset() {}

  public virtual void syncFields(MetaSyncContext ctx) {}
}

public interface IRpcError
{
  bool isOk();
}

public interface IRpc
{
  int getCode();
  IMetaStruct getRequest();
  IMetaStruct getResponse();
  IRpcError getError();
  void setError(IRpcError err);
}

public interface IDataReader 
{
  MetaIoError ReadI8(ref sbyte v);
  MetaIoError ReadU8(ref byte v);
  MetaIoError ReadI16(ref short v);
  MetaIoError ReadU16(ref ushort v);
  MetaIoError ReadI32(ref int v);
  MetaIoError ReadU32(ref uint v);
  MetaIoError ReadU64(ref ulong v);
  MetaIoError ReadI64(ref long v);
  MetaIoError ReadFloat(ref float v);
  MetaIoError ReadBool(ref bool v);
  MetaIoError ReadDouble(ref double v);
  MetaIoError ReadString(ref string v);
  MetaIoError ReadRaw(ref byte[] v, ref int vlen);
  MetaIoError ReadNil();
  MetaIoError BeginContainer(); 
  MetaIoError GetContainerSize(ref int v);
  MetaIoError EndContainer(); 
}

public interface IDataWriter 
{
  MetaIoError WriteI8(sbyte v);
  MetaIoError WriteU8(byte v);
  MetaIoError WriteI16(short v);
  MetaIoError WriteU16(ushort v);
  MetaIoError WriteI32(int v);
  MetaIoError WriteU32(uint v);
  MetaIoError WriteI64(long v);
  MetaIoError WriteU64(ulong v);
  MetaIoError WriteFloat(float v);
  MetaIoError WriteBool(bool v);
  MetaIoError WriteDouble(double v);
  MetaIoError WriteString(string v);
  MetaIoError WriteRaw(byte[] v);
  MetaIoError BeginContainer(int len); 
  MetaIoError EndContainer(); 
  MetaIoError End(); 
  MetaIoError WriteNil();
}

public static class Meta
{
  public delegate void LogCb(string text);
  public static LogCb LogError = DefaultLog;
  public static LogCb LogWarn = DefaultLog;
  public static LogCb LogDebug = DefaultLog;

  public struct BitfieldsContext
  {
    long fields_mask;
    int curr_field_idx;

    MetaSyncContext ctx;

    readonly bool use_mask;
    
    public BitfieldsContext(MetaSyncContext ctx, long fields_mask)
    {
      this.ctx = ctx;
      this.use_mask = ctx.IsMaskUsed();
      this.fields_mask = fields_mask;
      this.curr_field_idx = -1;
    }

    public void SyncMaskHeader() 
    {
      if(!use_mask)
        return;
      
      if(ctx.is_read)
      {
        ensure(ctx.reader.ReadNil());
        ensure(ctx.reader.ReadI64(ref fields_mask));
      }
      else
      {
        ensure(ctx.writer.WriteNil());
        ensure(ctx.writer.WriteI64(fields_mask));
      }
    }

    public MetaSyncFieldOpts GetCurrentOpts()
    {
      if(!use_mask || curr_field_idx < 0 || curr_field_idx > 63)
        return 0;

      long curr_field_ptr = 1L << curr_field_idx;
      if((curr_field_ptr & fields_mask) == 0)
        return MetaSyncFieldOpts.SKIP_NOT_IN_MASK;

      return 0;
    }

    public MetaSyncFieldOpts GetNextOpts()
    {
      Advance();
      return GetCurrentOpts();
    }

    public void Advance()
    {
      curr_field_idx++;
#if DEBUG
      if(curr_field_idx > 64)
      {
        LogError("overflow in @bitfields struct. Does it have > 64 fields?");
        throw new MetaException(MetaIoError.GENERIC);
      }
#endif
    }
  }
  
  public const int MASK_HEADER_FIELDS_COUNT = 2;

  public static List<int> tmp_enums_list = new List<int>(); 

  static void DefaultLog(string s)
  {}

  public delegate string L_TCb(string text);
  public static L_TCb L_T;

  public delegate string L_FromListCb(IList<string> list);
  public static L_FromListCb L_FromList;

  public delegate string L_PFromListCb(IList<string> list, double force_n = double.NaN);
  public static L_PFromListCb L_Pluralize;

  public delegate bool L_PListCheckCb(IList<string> list, string plural_mark);
  public static L_PListCheckCb L_IsPlural;

  public static void ensure(MetaIoError err)
  {
    if(err != 0)
      throw new MetaException(err);
  }
  
  static bool canSkipOptionalRead(MetaIoError err, MetaSyncFieldOpts opts)
  {
    return err != 0 && (opts & MetaSyncFieldOpts.SKIP_OPTIONAL) == MetaSyncFieldOpts.SKIP_OPTIONAL;
  }

  static MetaIoError checkRead(MetaIoError err, MetaSyncFieldOpts opts)
  {
    if(canSkipOptionalRead(err, opts))
    {
      LogWarn("Skipping optional field");
      return MetaIoError.NONE;
    }
    else
      return err;
  }

  public static void Sync(MetaSyncContext ctx, ref byte[] v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      int len = 0;
      ensure(checkRead(ctx.reader.ReadRaw(ref v, ref len), opts));
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteRaw(v));
  }

  public static void Sync(MetaSyncContext ctx, ref string v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadString(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteString(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredString v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      string tmp = string.Empty;
      ensure(checkRead(ctx.reader.ReadString(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteString(v));
  }

  public static void Sync(MetaSyncContext ctx, ref long v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadI64(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI64(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredLong v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      long tmp = 0;
      ensure(checkRead(ctx.reader.ReadI64(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI64(v));
  }

  public static void Sync(MetaSyncContext ctx, ref int v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadI32(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI32(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredInt v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      int tmp = 0;
      ensure(checkRead(ctx.reader.ReadI32(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI32(v));
  }

  public static void Sync(MetaSyncContext ctx, ref short v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadI16(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI16(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredShort v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      short tmp = 0;
      ensure(checkRead(ctx.reader.ReadI16(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI16(v));
  }

  public static void Sync(MetaSyncContext ctx, ref sbyte v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadI8(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI8(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredSByte v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      sbyte tmp = 0;
      ensure(checkRead(ctx.reader.ReadI8(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteI8(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ulong v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadU64(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU64(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredULong v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      ulong tmp = 0;
      ensure(checkRead(ctx.reader.ReadU64(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU64(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ushort v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadU16(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU16(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredUShort v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      ushort tmp = 0;
      ensure(checkRead(ctx.reader.ReadU16(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU16(v));
  }

  public static void Sync(MetaSyncContext ctx, ref uint v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadU32(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU32(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredUInt v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      uint tmp = 0;
      ensure(checkRead(ctx.reader.ReadU32(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU32(v));
  }

  public static void Sync(MetaSyncContext ctx, ref byte v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadU8(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU8(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredByte v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      byte tmp = 0;
      ensure(checkRead(ctx.reader.ReadU8(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteU8(v));
  }

  public static void Sync(MetaSyncContext ctx, ref bool v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadBool(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteBool(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredBool v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      bool tmp = false;
      ensure(checkRead(ctx.reader.ReadBool(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteBool(v));
  }

  public static void Sync(MetaSyncContext ctx, ref float v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadFloat(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteFloat(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredFloat v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      float tmp = 0f;
      ensure(checkRead(ctx.reader.ReadFloat(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteFloat(v));
  }

  public static void Sync(MetaSyncContext ctx, ref double v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
      ensure(checkRead(ctx.reader.ReadDouble(ref v), opts));
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteDouble(v));
  }

  public static void Sync(MetaSyncContext ctx, ref ObscuredDouble v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      double tmp = 0;
      ensure(checkRead(ctx.reader.ReadDouble(ref tmp), opts));
      v = tmp;
    }
    else if(ctx.CanWriteField(opts))
      ensure(ctx.writer.WriteDouble(v));
  }

  static int SyncBeginListGetSize(MetaSyncContext ctx, IList v, MetaSyncFieldOpts opts)
  {
    if(ctx.CanReadField(opts))
    {
      var err = ctx.reader.BeginContainer(); 
      if(canSkipOptionalRead(err, opts))
      {
        LogWarn("Skipping optional array field");
        return -1;
      }
      ensure(err);

      int size = 0;
      ensure(ctx.reader.GetContainerSize(ref size));

      return size;
    }
    else if(ctx.CanWriteField(opts))
    {
      int size = v == null ? 0 : v.Count;
      ensure(ctx.writer.BeginContainer(size));
      return size;
    }
    else
      return -1;
  }

  static int SyncBeginList<T>(MetaSyncContext ctx, List<T> v, ref MetaSyncFieldOpts opts)
  {
    int size = SyncBeginListGetSize(ctx, v, opts);
    if(size == -1)
      return size;

    if(ctx.is_read && v.Capacity < size)
      v.Capacity = size;

    //NOTE: unsetting opts for array items
    opts &= ~MetaSyncFieldOpts.SKIP_OPTIONAL;
    opts &= ~MetaSyncFieldOpts.SKIP_NOT_IN_MASK;
    return size;
  }

  static void SyncEndList(MetaSyncContext ctx, IList v)
  {
    if(ctx.is_read)
      ensure(ctx.reader.EndContainer());
    else
      ensure(ctx.writer.EndContainer());
  }

  public static void Sync(MetaSyncContext ctx, List<string> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? "" : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<long> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(long) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<int> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(int) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<short> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(short) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<sbyte> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(sbyte) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<ulong> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(ulong) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<uint> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(uint) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<ushort> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(ushort) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<byte> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(byte) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<bool> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(bool) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<float> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(float) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync(MetaSyncContext ctx, List<double> v, MetaSyncFieldOpts opts = 0)
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? default(double) : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }
  
  public static void Sync<T>(MetaSyncContext ctx, List<T> v, MetaSyncFieldOpts opts = 0) where T : IMetaStruct, new()
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;

    if(ctx.is_read)
      v.Clear();

    for(int i = 0; i < size; ++i)
    {
      var tmp = ctx.is_read ? new T() : v[i];
      Sync(ctx, ref tmp, opts);
      if(ctx.is_read)
        v.Add(tmp);
    }
    SyncEndList(ctx, v);
  }

  public static IMetaStruct SyncGeneric(MetaSyncContext ctx, IMetaStruct v, MetaSyncFieldOpts opts = 0)
  {
    if(ctx.CanReadField(opts))
    {
      ensure(ctx.reader.BeginContainer());

      uint clid = 0;
      ensure(ctx.reader.ReadU32(ref clid));
      
      //NOTE: when reading we ignore the passed argument
      v = ctx.factory(clid);
      if(v == null)
      {
        LogError("Could not create struct: " + clid);
        ensure(MetaIoError.TYPE_DONT_MATCH);
      }

      v.reset();
      v.syncFields(ctx);
      ensure(ctx.reader.EndContainer());
    }
    else if(ctx.CanWriteField(opts))
    {
      ensure(ctx.writer.BeginContainer(v.getFieldsCount() + 1));
      ensure(ctx.writer.WriteU32(v.CLASS_ID()));
      v.syncFields(ctx);
      ensure(ctx.writer.EndContainer());

    }
    return v;
  }

  public static void SyncGeneric<T>(MetaSyncContext ctx, List<T> v, MetaSyncFieldOpts opts = 0) where T : IMetaStruct, new()
  {
    int size = SyncBeginList(ctx, v, ref opts);
    if(size == -1)
      return;
    for(int i = 0; i < size; ++i)
    {
      var tmp = SyncGeneric(ctx, ctx.is_read ? default(T) : v[i]);
      if(ctx.is_read)
        v.Add((T)tmp);
    }
    SyncEndList(ctx, v);
  }

  public static void Sync<T>(MetaSyncContext ctx, ref T v, MetaSyncFieldOpts opts = 0) where T : IMetaStruct
  {
    if(ctx.CanReadField(opts))
    {
      var err = ctx.reader.BeginContainer();
      if(canSkipOptionalRead(err, opts))
      {
        LogWarn("Skipping optional struct field");
        return;
      }

      ensure(err);
      v.reset();
      v.syncFields(ctx);
      ensure(ctx.reader.EndContainer());  
    }
    else if(ctx.CanWriteField(opts))
    {
      int array_size = getWriteFieldsCount(ctx, v);
      ensure(ctx.writer.BeginContainer(array_size));
      v.syncFields(ctx);
      ensure(ctx.writer.EndContainer());
    }
  }

  public static MetaIoError SyncSafe<T>(MetaSyncContext ctx, ref T v, MetaSyncFieldOpts opts = 0) where T : IMetaStruct
  {
    try 
    {
      Sync(ctx, ref v, opts);
    }
    catch(MetaException e)
    {
      LogError(e.Message + " " + e.StackTrace);
      return e.err;
    }
    catch(Exception e)
    {
      LogError(e.Message + " " + e.StackTrace);
      return MetaIoError.GENERIC;
    }
    return MetaIoError.NONE;
  }

  static int getWriteFieldsCount(MetaSyncContext ctx, IMetaStruct v)
  {
    if(ctx.IsMaskUsed())
      return v.getWritableFieldsCount();
    else
      return v.getFieldsCount();
  }

  public static MetaSyncContext PrepareForClone<T>(ref T src) where T : IMetaStruct
  {
    var stream = new MemoryStream();

    var ctx = new MetaSyncContext() {
      is_read = false,
      reader = new MsgPackDataReader(stream),
      writer = new MsgPackDataWriter(stream),
      opts = 0
    };

    Sync(ctx, ref src);

    ctx.is_read = true;
    stream.Position = 0;

    return ctx;
  }

  //Shared mask utils below

  public static int GetDirtyFieldsCount(long fields_mask, int fields_count)
  {
    int changed_fields = 0;
    long ptr = 1L;
    for(int i=0; i<fields_count; ++i, ptr = ptr << 1)
    {
      if((ptr & fields_mask) != 0)
        changed_fields++;
    }
    return changed_fields;
  }

  public static void SetFieldDirty(ref long fields_mask, int field_index)
  {
    long diff = 1L << field_index;
    fields_mask |= diff;
  }

  public static bool IsFieldDirty(long fields_mask, int field_index)
  {
    return (fields_mask & 1L << field_index) != 0;
  }

  public static void ClearList<T>(ref List<T> v) 
  {
    if(v == null) 
      v = new List<T>(); 
    v.Clear();
  }

  public static string I18NPick(string raw_val, List<string> list_val, string plural_marker, double pluralize_for_n)
  {
    if(raw_val.Length != 0) 
      return Meta.L_T(raw_val);

    if(Meta.L_IsPlural(list_val, plural_marker)) 
      return Meta.L_Pluralize(list_val, pluralize_for_n);

    return Meta.L_FromList(list_val);
  }

  public static void Reset<T>(ref T v) where T : IMetaStruct, new()
  {
    if(v == null) 
      v = new T(); 
    v.reset();
  }
}

public class MsgPackDataWriter : IDataWriter 
{
  Stream stream;
  MsgPackWriter io;
  Stack<int> space = new Stack<int>();

  public MsgPackDataWriter(Stream _stream) 
  {
    reset(_stream);
  }

  public void reset(Stream _stream)
  {
    stream = _stream;
    io = new MsgPackWriter(stream);
    space.Clear();
    space.Push(1);
  }

  MetaIoError decSpace() 
  {
    if(space.Count == 0)
      return MetaIoError.NO_SPACE_LEFT_IN_ARRAY;
    
    int left = space.Pop();
    left--;
    if(left < 0)
      return MetaIoError.NO_SPACE_LEFT_IN_ARRAY;
    
    space.Push(left);
    return 0;
  }

  public MetaIoError BeginContainer(int size) 
  {
    MetaIoError err = decSpace();
    if(err != 0)
      return err;
    
    space.Push(size);
    io.WriteArrayHeader(size);
    return 0;
  }

  public MetaIoError EndContainer() 
  {
    if(space.Count <= 1)
      return MetaIoError.ARRAY_STACK_IS_EMPTY;
    
    int left = space.Pop();
    if(left != 0)
      return MetaIoError.HAS_LEFT_SPACE;
    
    return 0;
  }
  
  public MetaIoError End() 
  {
    if(space.Count != 1)
      return MetaIoError.ARRAY_STACK_IS_EMPTY;
    
    return 0;
  }

  public MetaIoError WriteI8(sbyte v) 
  {
    io.Write(v);
    return decSpace();
  }
 
  public MetaIoError WriteU8(byte v) 
  {
    io.Write(v);
    return decSpace();
  }
  
  public MetaIoError WriteI16(short v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteU16(ushort v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteI32(int v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteU32(uint v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteU64(ulong v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteI64(long v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteBool(bool v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteFloat(float v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteDouble(double v) 
  {
    io.Write(v);
    return decSpace();
  }

  public MetaIoError WriteString(string v) 
  {
    if(v == null) 
      io.Write("");
    else
      io.Write(v);
    
    return decSpace();
  }

  public MetaIoError WriteNil()
  {
    io.WriteNil();
    
    return decSpace();
  }

  public MetaIoError WriteRaw(byte[] v) 
  {
    io.Write(v);

    return decSpace();
  }
}

public class MsgPackDataReader : IDataReader 
{
  Stream stream;
  MsgPackReader io;

  public struct ContainerPosition
  {
    public int max;
    public int curr;

    public ContainerPosition(int length)
    {
      curr = 0;
      max = length - 1;
    }
  }

  Stack<ContainerPosition> stack = new Stack<ContainerPosition>();
  
  public MsgPackDataReader(Stream _stream) 
  { 
    reset(_stream);
  }

  public void reset(Stream _stream)
  {
    stream = _stream;
    stack.Clear();
    io = new MsgPackReader(stream);
  }

  public void setPos(long pos)
  {
    stream.Position = pos;
    stack.Clear();
  }

  int nextInt(ref MetaIoError err) 
  {
    if(!ContainerPositionValid())
    {
      err = MetaIoError.DATA_MISSING;
      return 0;
    }

    if(!io.Read()) 
    {
      err = MetaIoError.FAIL_READ;
      return 0;
    }
    
    ContainerPositionMoveNext();
    
    if(io.IsSigned())
      return io.ValueSigned;
    else if(io.IsUnsigned())
      return (int)io.ValueUnsigned;
    else
    {
      Meta.LogWarn("Got type: " + io.Type);
      err = MetaIoError.TYPE_DONT_MATCH; 
      return 0;
    }
  }
   
  uint nextUint(ref MetaIoError err) 
  {
    if(!ContainerPositionValid())
    {
      err = MetaIoError.DATA_MISSING;
      return 0;
    }

    if(!io.Read()) 
    {
      err = MetaIoError.FAIL_READ;
      return 0;
    }
    
    ContainerPositionMoveNext();
    
    if(io.IsUnsigned())
      return io.ValueUnsigned;
    else if(io.IsSigned())
      return (uint)io.ValueSigned;
    else
    {
      Meta.LogWarn("Got type: " + io.Type);
      err = MetaIoError.TYPE_DONT_MATCH; 
      return 0;
    }
  }

  bool nextBool(ref MetaIoError err) 
  {
    if(!ContainerPositionValid())
    {
      err = MetaIoError.DATA_MISSING;
      return false;
    }

    if(!io.Read()) 
    {
      err = MetaIoError.FAIL_READ;
      return false;
    }
    
    ContainerPositionMoveNext();
    
    if(io.IsBoolean())
      return (bool)io.ValueBoolean;
    else if(io.IsUnsigned())
      return io.ValueUnsigned != 0;
    else if(io.IsSigned())
      return (uint)io.ValueSigned != 0;
    else
    {
      Meta.LogWarn("Got type: " + io.Type);
      err = MetaIoError.TYPE_DONT_MATCH; 
      return false;
    }
  }

  ulong nextUint64(ref MetaIoError err) 
  {
    if(!ContainerPositionValid())
    {
      err = MetaIoError.DATA_MISSING;
      return 0;
    }

    if(!io.Read()) 
    {
      err = MetaIoError.FAIL_READ;
      return 0;
    }
    
    ContainerPositionMoveNext();

    if(io.IsUnsigned())
      return io.ValueUnsigned;
    else if(io.IsSigned())
      return (ulong)io.ValueSigned;
    else if(io.IsUnsigned64())
      return io.ValueUnsigned64;
    else if(io.IsSigned64())
      return (ulong)io.ValueSigned64;
    else
    {
      Meta.LogWarn("Got type: " + io.Type);
      err = MetaIoError.TYPE_DONT_MATCH; 
      return 0;
    }
  }

  long nextInt64(ref MetaIoError err) 
  {
    if(!ContainerPositionValid())
    {
      err = MetaIoError.DATA_MISSING;
      return 0;
    }

    if(!io.Read()) 
    {
      err = MetaIoError.FAIL_READ;
      return 0;
    }
    
    ContainerPositionMoveNext();

    if(io.IsUnsigned())
      return (long)io.ValueUnsigned;
    else if(io.IsSigned())
      return io.ValueSigned;
    else if(io.IsUnsigned64())
      return (long)io.ValueUnsigned64;
    else if(io.IsSigned64())
      return io.ValueSigned64;
    else
    {
      Meta.LogWarn("Got type: " + io.Type);
      err = MetaIoError.TYPE_DONT_MATCH; 
      return 0;
    }
  }
  
  public MetaIoError ReadI8(ref sbyte v) 
  {
    MetaIoError err = 0;
    v = (sbyte) nextInt(ref err);
    return err;
  }
  
  public MetaIoError ReadI16(ref short v) 
  {
    MetaIoError err = 0;
    v = (short) nextInt(ref err);
    return err;
  }
  
  public MetaIoError ReadI32(ref int v) 
  {
    MetaIoError err = 0;
    v = nextInt(ref err);
    return err;
  }
  
  public MetaIoError ReadU8(ref byte v) 
  {
    MetaIoError err = 0;
    v = (byte) nextUint(ref err);
    return err;
  }
  
  public MetaIoError ReadU16(ref ushort v) 
  {
    MetaIoError err = 0;
    v = (ushort) nextUint(ref err);
    return err;
  }
  
  public MetaIoError ReadU32(ref uint v) 
  {
    MetaIoError err = 0;
    v = nextUint(ref err);
    return err;
  }

  public MetaIoError ReadU64(ref ulong v) 
  {
    MetaIoError err = 0;
    v = nextUint64(ref err);
    return err;
  }

  public MetaIoError ReadI64(ref long v) 
  {
    MetaIoError err = 0;
    v = nextInt64(ref err);
    return err;
  }

  public MetaIoError ReadBool(ref bool v) 
  {
    MetaIoError err = 0;
    v = nextBool(ref err);
    return err;
  }

  public MetaIoError ReadFloat(ref float v) 
  {
    if(!ContainerPositionValid())
      return MetaIoError.DATA_MISSING;

    if(!io.Read()) 
    {
      return MetaIoError.FAIL_READ;
    }

    if(io.IsUnsigned()) 
    {
      v = io.ValueUnsigned;
    } 
    else if(io.IsSigned()) 
    {
      v = io.ValueSigned;
    } 
    else 
    {
      switch(io.Type)
      {
        case TypePrefixes.Float:
          v = io.ValueFloat;
          break;
        case TypePrefixes.Double:
          var tmp = io.ValueDouble;
          //TODO:
          //if(tmp > float.MaxValue || tmp < float.MinValue)
          //{
          //  Meta.LogWarn("Double -> Float bad conversion: " + tmp);
          //  return MetaIoError.TYPE_DONT_MATCH; 
          //}
          v = (float) tmp;
          break;
        default:
          Meta.LogWarn("Got type: " + io.Type);
          return MetaIoError.TYPE_DONT_MATCH; 
      }
    }
    ContainerPositionMoveNext();
    return 0;
  }

  public MetaIoError ReadDouble(ref double v) 
  {
    if(!ContainerPositionValid())
      return MetaIoError.DATA_MISSING;

    if(!io.Read()) 
    {
      return MetaIoError.FAIL_READ;
    }

    if(io.IsUnsigned()) 
    {
      v = io.ValueUnsigned;
    } 
    else if(io.IsSigned()) 
    {
      v = io.ValueSigned;
    } 
    else 
    {
      switch(io.Type)
      {
        case TypePrefixes.Float:
          v = (double) io.ValueFloat;
          break;
        case TypePrefixes.Double:
          v = io.ValueDouble;
          break;
        case TypePrefixes.UInt64:
          v = (double) io.ValueUnsigned64;
          break;
        case TypePrefixes.Int64:
          v = (double) io.ValueSigned64;    
          break;
        default:
          Meta.LogWarn("Got type: " + io.Type);
          return MetaIoError.TYPE_DONT_MATCH; 
      }
    }
    ContainerPositionMoveNext();
    return 0;
  }

  public MetaIoError ReadRaw(ref byte[] v, ref int vlen) 
  {
    if(!ContainerPositionValid())
      return MetaIoError.DATA_MISSING;

    if(!io.Read()) 
      return MetaIoError.FAIL_READ;

    if(!io.IsRaw()) 
    {
      Meta.LogWarn("Got type: " + io.Type);
      return MetaIoError.TYPE_DONT_MATCH;
    }

    vlen = (int)io.Length;
    if(v == null)
      v = new byte[vlen];
    else if(v.Length < vlen)
      Array.Resize(ref v, vlen);
    io.ReadValueRaw(v, 0, vlen);
    ContainerPositionMoveNext();
    return 0;
  }

  public MetaIoError ReadNil()
  {
    if(!ContainerPositionValid())
      return MetaIoError.DATA_MISSING;

    if(!io.Read()) 
      return MetaIoError.FAIL_READ;

    if(io.Type != TypePrefixes.Nil)
    {
      Meta.LogWarn("Got type: " + io.Type);
      return MetaIoError.TYPE_DONT_MATCH;
    }

    ContainerPositionMoveNext();
    return 0;
  }

  public MetaIoError ReadString(ref string v) 
  {
    if(!ContainerPositionValid())
      return MetaIoError.DATA_MISSING;

    if(!io.Read()) 
      return MetaIoError.FAIL_READ;

    if(!io.IsRaw()) 
    {
      Meta.LogWarn("Got type: " + io.Type);
      return MetaIoError.TYPE_DONT_MATCH;
    }

    //TODO: use shared buffer for strings loading
    byte[] strval = new byte[io.Length];
    io.ReadValueRaw(strval, 0, strval.Length);
    v = System.Text.Encoding.UTF8.GetString(strval);
    ContainerPositionMoveNext();
    return 0;
  }

  public MetaIoError BeginContainer() 
  {
    if(!ContainerPositionValid())
      return MetaIoError.DATA_MISSING;

    if(!io.Read())
      return MetaIoError.FAIL_READ;

    if(!io.IsArray())
    {
      Meta.LogWarn("Got type: " + io.Type);
      return MetaIoError.TYPE_DONT_MATCH;
    }

    ContainerPosition ap = new ContainerPosition((int)io.Length);
    stack.Push(ap);
    return 0;
  } 

  public MetaIoError GetContainerSize(ref int v) 
  {
    if(!io.IsArray())
    {
      Meta.LogWarn("Got type: " + io.Type);
      return MetaIoError.TYPE_DONT_MATCH;
    }

    v = (int) io.Length;
    return 0;
  }

  void SkipField()
  {
    if(!io.Read())
      return;

    if(!io.IsArray() && !io.IsMap())
    {
      //NOTE: if value is a raw string we need to read all of its data
      if(io.IsRaw())
        io.ReadRawString();
      return;
    }
    
    uint array_len = io.Length; 
    for(uint i=0; i<array_len; ++i)
      SkipField();
  }

  void SkipTrailingFields() 
  {
    while(ContainerEntriesLeft() > -1)
    {
      SkipField();
      ContainerPositionMoveNext();
    }
  }

  public MetaIoError EndContainer() 
  {
    SkipTrailingFields();
    stack.Pop();
    ContainerPositionMoveNext();
    return 0;
  }

  int ContainerEntriesLeft()
  {
    if(stack.Count == 0)
      return 0;
    ContainerPosition ap = stack.Peek();
    return ap.max - ap.curr;
  }

  bool ContainerPositionValid()
  {
    return ContainerEntriesLeft() >= 0;
  }

  void ContainerPositionMoveNext()
  {
    if(stack.Count > 0)
    {
      ContainerPosition ap = stack.Pop();
      ap.curr++;
      stack.Push(ap);
    }
  }
}

} //namespace metagen