public override void Write(IBitWriter writer)
        {
            base.Write(writer);

            writer.WriteUInt64(ExportTimestamp(this._Timestamp));
            writer.WriteString(this._SaveFileName);
            writer.WriteUInt16(3);  // gameVersion
            writer.WriteUInt16(22); // saveVersion
            writer.WriteUInt16(10); // ??
            writer.WriteUInt16(0);  // ??
            writer.WriteUInt32(this._UserBuildInfo);
            writer.WriteString(this._LevelName);
            writer.WriteUInt32(this._Unknown1);
            writer.WriteStringList(this._PreloadedBundleNames);
            writer.WriteStringDictionary(this._LayerInclusion);

            writer.WriteUInt16((ushort)this._BundleHeaps.Count, 12);
            foreach (var instance in this._BundleHeaps)
            {
                writer.PushFrameLength(24);
                writer.WriteString(instance.Unknown1);
                writer.WriteUInt32(instance.Unknown2);
                writer.WriteUInt32(instance.Unknown3);
                writer.WriteUInt8((byte)instance.Type);
                writer.WriteUInt32(instance.Unknown4);
                writer.WriteBoolean(instance.Unknown5);
                writer.WriteUInt8(instance.Unknown6);
                writer.WriteUInt8(instance.Unknown7);
                writer.WriteUInt32(instance.Unknown8);
                writer.PopFrameLength();
            }

            writer.WriteUInt16((ushort)this._Unknown2.Count, 12);
            foreach (var instance in this._Unknown2)
            {
                writer.PushFrameLength(24);
                writer.WriteUInt16(instance.Unknown1);
                writer.WriteUInt16(instance.Unknown2);
                writer.WriteUInt8(instance.Unknown3);
                writer.PopFrameLength();
            }

            writer.WriteGuid(this._LevelHash);

            writer.WriteUInt32(0, 20); // unknown5

            writer.WriteUInt16(this._Unknown3);
            if (this._Unknown3 >= 5)
            {
                writer.WriteUInt16(this._Unknown4);
            }
            writer.WriteBoolean(this._Unknown5);

            writer.PushFramePosition(26);

            var componentDataPositionPosition = writer.Position;

            writer.WriteUInt32(0, 26);

            var entityDataOffsets = new List <Tuple <Entities.RawEntity, uint?, uint?> >();

            writer.PushFrameLength(32);
            foreach (var rawEntity in this._Entities)
            {
                uint?entityData0Offset = null;
                if (rawEntity.Data0Bytes != null)
                {
                    entityData0Offset = (uint)writer.Position;
                    writer.PushFrameLength(24);
                    writer.WriteBits(rawEntity.Data0Bytes, rawEntity.Data0Length);
                    writer.PopFrameLength();
                }
                uint?entityData1Offset = null;
                if (rawEntity.Data1Bytes != null)
                {
                    entityData1Offset = (uint)writer.Position;
                    writer.PushFrameLength(24);
                    writer.WriteBits(rawEntity.Data1Bytes, rawEntity.Data1Length);
                    writer.PopFrameLength();
                }
                entityDataOffsets.Add(
                    new Tuple <Entities.RawEntity, uint?, uint?>(
                        rawEntity,
                        entityData0Offset,
                        entityData1Offset));
            }
            writer.PopFrameLength();

            var unknown9 = writer.Position;

            writer.PushFrameLength(24);
            writer.PushFrameLength(24);
            writer.WriteString(this._Unknown6);
            writer.WriteString(this._Unknown7);
            writer.WriteString(this._SaveName);
            writer.PopFrameLength();
            writer.WriteUInt32(this._Unknown8);
            writer.WriteGuid(this._Unknown9);
            writer.WriteUInt32(this._Unknown10);
            writer.PopFrameLength();
            writer.WriteUInt32((uint)unknown9, 26);

            var agentDataOffsetLookup = new Dictionary <byte, uint[]>();

            writer.PushFrameLength(32);
            WriteAgentData(writer, this._Agents, agentDataOffsetLookup, 0, (w, t) => t.Write1(w, this._Unknown4));
            WriteAgentData(writer, this._Agents, agentDataOffsetLookup, 1, (w, t) => t.Write2(w));
            WriteAgentData(writer, this._Agents, agentDataOffsetLookup, 2, (w, t) => t.Write3(w, this._Unknown4));
            WriteAgentData(writer, this._Agents, agentDataOffsetLookup, 3, (w, t) => t.Write4(w));
            WriteAgentData(writer, this._Agents, agentDataOffsetLookup, 4, (w, t) => t.Write5(w));
            writer.PopFrameLength();

            writer.WriteUInt8((byte)agentDataOffsetLookup.Count, 4);
            foreach (var kv in agentDataOffsetLookup)
            {
                writer.WriteUInt8(kv.Key);
                for (int j = 0; j < 5; j++)
                {
                    writer.WriteUInt32(kv.Value[j], 26);
                }
            }

            writer.PushFrameLength(24);

            writer.WriteUInt16((ushort)entityDataOffsets.Count);
            foreach (var tuple in entityDataOffsets)
            {
                var rawEntity         = tuple.Item1;
                var entityData0Offset = tuple.Item2;
                var entityData1Offset = tuple.Item3;
                writer.WriteUInt32(rawEntity.Id);
                writer.WriteBoolean(entityData0Offset.HasValue);
                if (entityData0Offset.HasValue == true)
                {
                    writer.WriteUInt32(entityData0Offset.Value, 26);
                }
                writer.WriteBoolean(entityData1Offset.HasValue);
                if (entityData1Offset.HasValue == true)
                {
                    writer.WriteUInt32(entityData1Offset.Value, 26);
                }
            }

            writer.WriteUInt16((ushort)this._Unknown11.Count);
            foreach (var unknown17 in this._Unknown11)
            {
                writer.WriteUInt32(unknown17);
            }

            writer.WriteUInt16(0); // unknown18

            writer.WriteUInt16((ushort)this._Unknown12.Count);
            foreach (var unknown21 in this._Unknown12)
            {
                writer.WriteUInt32(unknown21);
            }

            writer.PopFrameLength();

            writer.PopFramePosition();

            writer.PushFrameLength(24);
            writer.WriteUInt8((byte)this._Agents.Count, 4);
            foreach (var kv in this._Agents)
            {
                var index    = kv.Key;
                var agent    = kv.Value;
                var nameHash = AgentFactory.GetNameHash(agent.AgentName);
                writer.WriteUInt32(nameHash);
                writer.WriteUInt8(index);
                agent.Write0(writer, index);
            }
            writer.PopFrameLength();

            if (writer.FrameCount != 0)
            {
                throw new SaveFormatException();
            }

            var componentDataPosition = writer.Position;

            writer.Position = componentDataPositionPosition;
            writer.WriteUInt32((uint)componentDataPosition, 26);
            writer.Position = componentDataPosition;

            writer.PushFrameLength(32);
            writer.WriteUInt16(this._Unknown13);
            if (this._Unknown13 == 1)
            {
                writer.WriteUInt16((ushort)this._ComponentContainerAgents.Count);
                foreach (var component in this._ComponentContainerAgents)
                {
                    writer.PushFrameLength(24);
                    var componentNameHash = ComponentContainerAgentFactory.GetNameHash(component.AgentName);
                    writer.WriteUInt32(componentNameHash);
                    writer.WriteUInt16(component.AgentVersion);
                    component.Write(writer);
                    writer.PopFrameLength();
                }
            }
            writer.PopFrameLength();

            if (writer.FrameCount != 0)
            {
                throw new SaveFormatException();
            }
        }
        public override void Read(IBitReader reader)
        {
            base.Read(reader);

            this._Timestamp    = ImportTimestamp(reader.ReadUInt64());
            this._SaveFileName = reader.ReadString();
            var gameVersion = reader.ReadUInt16();
            var saveVersion = reader.ReadUInt16();
            var unknown1    = reader.ReadUInt16(); // 10
            var unknown2    = reader.ReadUInt16(); // 0

            this._UserBuildInfo = reader.ReadUInt32();

            if (gameVersion != 3)
            {
                throw new SaveFormatException("unsupported save data game version");
            }

            if (saveVersion < 20 || saveVersion > 22)
            {
                throw new SaveFormatException("unsupported save data save version");
            }

            if (unknown1 != 10 || unknown2 != 0)
            {
                throw new SaveFormatException("unsupported save data header data");
            }

            this._LevelName = reader.ReadString();
            this._Unknown1  = reader.ReadUInt32();
            reader.ReadStringList(this._PreloadedBundleNames);
            reader.ReadStringDictionary(this._LayerInclusion);

            var bundleHeapCount = reader.ReadUInt16(12);

            this._BundleHeaps.Clear();
            for (int i = 0; i < bundleHeapCount; i++)
            {
                reader.PushFrameLength(24);
                var bundleHeap = new Data.BundleHeapInfo();
                bundleHeap.Unknown1 = reader.ReadString();
                bundleHeap.Unknown2 = reader.ReadUInt32();
                bundleHeap.Unknown3 = reader.ReadUInt32();
                bundleHeap.Type     = (Data.BundleHeapType)reader.ReadUInt8();
                bundleHeap.Unknown4 = reader.ReadUInt32();
                bundleHeap.Unknown5 = reader.ReadBoolean();
                bundleHeap.Unknown6 = reader.ReadUInt8();
                bundleHeap.Unknown7 = reader.ReadUInt8();
                bundleHeap.Unknown8 = reader.ReadUInt32();
                if (saveVersion < 17)
                {
                    reader.SkipBoolean();
                }
                this._BundleHeaps.Add(bundleHeap);
                reader.PopFrameLength();
            }

            var unknown3Count = reader.ReadUInt16(12);

            this._Unknown2.Clear();
            for (int i = 0; i < unknown3Count; i++)
            {
                reader.PushFrameLength(24);
                var instance = new Data.SaveDataUnknown0();
                instance.Unknown1 = reader.ReadUInt16();
                instance.Unknown2 = reader.ReadUInt16();
                instance.Unknown3 = reader.ReadUInt8();
                this._Unknown2.Add(instance);
                reader.PopFrameLength();
            }

            // not actually a Guid, but we will borrow it for sake of simplicity
            this._LevelHash = reader.ReadGuid();

            var unknown5 = reader.ReadUInt32(20);

            if (unknown5 != 0)
            {
                throw new NotImplementedException();
            }
            reader.SkipBits((int)unknown5); // TODO(gibbed): position move

            this._Unknown3 = reader.ReadUInt16();
            this._Unknown4 = this._Unknown3 >= 5 ? reader.ReadUInt16() : (ushort)0;
            this._Unknown5 = reader.ReadBoolean();

            reader.PushFramePosition(26);

            var componentDataPosition = reader.ReadUInt32(26);

            var entityBulkDataLength   = reader.ReadUInt32();
            var entityBulkDataPosition = reader.Position;

            reader.SkipBits((int)entityBulkDataLength);

            var unknown9 = reader.Position;

            reader.PushFrameLength(saveVersion >= 18 ? 24 : 6);
            reader.PushFrameLength(24);
            this._Unknown6 = reader.ReadString();
            this._Unknown7 = reader.ReadString();
            this._SaveName = reader.ReadString();
            reader.PopFrameLength();

            this._Unknown8  = reader.ReadUInt32();
            this._Unknown9  = reader.ReadGuid();
            this._Unknown10 = reader.ReadUInt32();
            reader.PopFrameLength();

            var unknown16 = reader.ReadUInt32(26);

            if (unknown9 != unknown16)
            {
                throw new FormatException();
            }

            var agentBulkDataLength   = reader.ReadUInt32();
            var agentBulkDataPosition = reader.Position;

            reader.SkipBits((int)agentBulkDataLength);

            var agentDataCount        = reader.ReadUInt8(4);
            var agentDataOffsetLookup = new Dictionary <byte, uint[]>();

            for (int i = 0; i < agentDataCount; i++)
            {
                var index            = reader.ReadUInt8();
                var agentDataOffsets = new uint[5];
                for (int j = 0; j < 5; j++)
                {
                    var agentDataOffset = agentDataOffsets[j] = reader.ReadUInt32(26);
                    if (agentDataOffset != 0)
                    {
                        if (agentDataOffset < agentBulkDataPosition ||
                            agentDataOffset > agentBulkDataPosition + agentBulkDataLength)
                        {
                            throw new FormatException();
                        }
                    }
                }
                agentDataOffsetLookup.Add(index, agentDataOffsets);
            }

            reader.PushFrameLength(24);

            var entityDataCount   = reader.ReadUInt16();
            var entityDataOffsets = new Dictionary <uint, Tuple <uint?, uint?> >();

            for (int i = 0; i < entityDataCount; i++)
            {
                var  entityId          = reader.ReadUInt32();
                uint?entityData0Offset = null;
                uint?entityData1Offset = null;

                var entityHasData0 = reader.ReadBoolean();
                if (entityHasData0 == true)
                {
                    var entityDataOffset = reader.ReadUInt32(26);
                    if (entityDataOffset < entityBulkDataPosition ||
                        entityDataOffset > entityBulkDataPosition + entityBulkDataLength)
                    {
                        throw new FormatException();
                    }
                    entityData0Offset = entityDataOffset;
                }

                var entityHasData1 = reader.ReadBoolean();
                if (entityHasData1 == true)
                {
                    var entityDataOffset = reader.ReadUInt32(26);
                    if (entityDataOffset < entityBulkDataPosition ||
                        entityDataOffset > entityBulkDataPosition + entityBulkDataLength)
                    {
                        throw new FormatException();
                    }
                    entityData1Offset = entityDataOffset;
                }

                entityDataOffsets.Add(entityId, new Tuple <uint?, uint?>(entityData0Offset, entityData1Offset));
            }

            var unknown17Count = reader.ReadUInt16();

            this._Unknown11.Clear();
            for (int i = 0; i < unknown17Count; i++)
            {
                this._Unknown11.Add(reader.ReadUInt32());
            }

            var unknown18Count = reader.ReadUInt16();

            for (int i = 0; i < unknown18Count; i++)
            {
                reader.PushFrameLength(24);
                var unknown19      = reader.ReadUInt32();
                var unknown20Count = reader.ReadUInt16();
                var unknown20      = new uint[unknown20Count];
                for (int j = 0; j < unknown20Count; j++)
                {
                    unknown20[j] = reader.ReadUInt32();
                }
                reader.PopFrameLength();
                throw new NotImplementedException();
            }

            var unknown12Count = reader.ReadUInt16();

            this._Unknown12.Clear();
            for (int i = 0; i < unknown12Count; i++)
            {
                this._Unknown12.Add(reader.ReadUInt32());
            }

            reader.PopFrameLength();

            reader.PopFramePosition();

            reader.PushFrameLength(24);
            var agentCount = reader.ReadUInt8(4);

            this._Agents.Clear();
            for (int i = 0; i < agentCount; i++)
            {
                var nameHash = reader.ReadUInt32();
                var index    = reader.ReadUInt8();
                var agent    = AgentFactory.Create(nameHash);
                agent.Read0(reader, index);
                this._Agents.Add(index, agent);
            }
            reader.PopFrameLength();

            if (reader.FrameCount != 0)
            {
                throw new SaveFormatException();
            }

            if (reader.Position != componentDataPosition)
            {
                throw new SaveFormatException();
            }

            reader.PushFrameLength(32);
            this._ComponentContainerAgents.Clear();
            this._Unknown13 = reader.ReadUInt16();
            if (this._Unknown13 == 1)
            {
                var componentCount = reader.ReadUInt16();
                for (int i = 0; i < componentCount; i++)
                {
                    reader.PushFrameLength(24);
                    var componentNameHash = reader.ReadUInt32();
                    var componentVersion  = reader.ReadUInt16();
                    var component         = ComponentContainerAgentFactory.Create(componentNameHash);
                    component.Read(reader, componentVersion);
                    reader.PopFrameLength();
                    this._ComponentContainerAgents.Add(component);
                }
            }
            reader.PopFrameLength();

            ReadAgentData(reader, this._Agents, agentDataOffsetLookup, 0, (r, t) => t.Read1(r, this._Unknown4));
            ReadAgentData(reader, this._Agents, agentDataOffsetLookup, 1, (r, t) => t.Read2(r));
            ReadAgentData(reader, this._Agents, agentDataOffsetLookup, 2, (r, t) => t.Read3(r, this._Unknown4));
            ReadAgentData(reader, this._Agents, agentDataOffsetLookup, 3, (r, t) => t.Read4(r));
            ReadAgentData(reader, this._Agents, agentDataOffsetLookup, 4, (r, t) => t.Read5(r));

            /*
             * var entities = new List<Entities.Entity>();
             * foreach (var kv in entityDataOffsets)
             * {
             *  var entityDataFirstOffset = kv.Value.Item1;
             *  var entityDataSecondOffset = kv.Value.Item2;
             *
             *  var entity = Entities.EntityFactory.Create(kv.Key);
             *
             *  if (entityDataFirstOffset.HasValue == true)
             *  {
             *      reader.Position = (int)entityDataFirstOffset.Value;
             *      reader.PushFrameLength(24);
             *      entity.Read0(reader);
             *      reader.PopFrameLength();
             *  }
             *
             *  if (entityDataSecondOffset.HasValue == true)
             *  {
             *      reader.Position = (int)entityDataSecondOffset.Value;
             *      reader.PushFrameLength(24);
             *      entity.Read1(reader);
             *      reader.PopFrameLength();
             *  }
             *
             *  entities.Add(entity);
             * }
             */

            this._Entities.Clear();
            foreach (var kv in entityDataOffsets)
            {
                var entityData0Offset = kv.Value.Item1;
                var entityData1Offset = kv.Value.Item2;
                var rawEntity         = new Entities.RawEntity();
                rawEntity.Id = kv.Key;
                if (entityData0Offset.HasValue == true)
                {
                    reader.Position       = (int)entityData0Offset.Value;
                    rawEntity.Data0Length = (int)reader.ReadUInt32(24);
                    rawEntity.Data0Bytes  = reader.ReadBits(rawEntity.Data0Length);
                }
                if (entityData1Offset.HasValue == true)
                {
                    reader.Position       = (int)entityData1Offset.Value;
                    rawEntity.Data1Length = (int)reader.ReadUInt32(24);
                    rawEntity.Data1Bytes  = reader.ReadBits(rawEntity.Data1Length);
                }
                this._Entities.Add(rawEntity);
            }

            if (reader.FrameCount != 0)
            {
                throw new SaveFormatException();
            }

            if (reader.HasUnreadBits() == true)
            {
                throw new SaveFormatException();
            }
        }