ln.types/odb/values/ODBValue.cs

using System;
using System.Collections.Generic;
using System.IO;

/**
 * typeCode list
 * 
 * 0x0000   ODBNull
 * 0x0001   ODBStringValue
 * 0x0002   ODBList
 * 0x0003   ODBGuid
 * 
 * 0x0010   ODBInteger
 * 0x0011   ODBUInteger
 * 0x0012   ODBLong
 * 0x0013   ODBULong
 * 
 * 0x0018   ODBDouble
 * 
 * 0x1000   ODBDocument
 * 
 * 
 * 
 **/



namespace ln.types.odb.values
{
    public delegate ODBValue ODBValueFactory(object value);
    public delegate ODBValue ODBDeserialize(byte[] storageBytes, int offset, int length);

    public abstract class ODBValue
    {
        int storageTypeCode;

        public virtual object Value { get; protected set; }

        protected ODBValue(int storageTypeCode)
        {
            this.storageTypeCode = storageTypeCode;
        }

        protected ODBValue(int storageTypeCode, object value)
            : this(storageTypeCode)
        {
            Value = value;
        }

        public abstract byte[] ToStorage();

        public object AsObject => Value;

        public virtual string AsString => (string)Value;

        public virtual bool AsBool => (bool)Value;
        public virtual byte AsByte => (byte)Value;
        public virtual char AsChar => (char)Value;
        public virtual short AsShort => (short)Value;
        public virtual int AsInt => (int)Value;
        public virtual long AsLong => (long)Value;
        public virtual ushort AsUShort => (ushort)Value;
        public virtual uint AsUInt => (uint)Value;
        public virtual ulong AsULong => (ulong)Value;

        public virtual double AsDouble => (double)Value;
        public virtual float AsFloat => (float)Value;

        public virtual Guid AsGuid => (Guid)Value;
        public virtual DateTime AsDateTime => (DateTime)Value;
        public virtual TimeSpan AsTimeSpan => (TimeSpan)Value;

        public virtual ODBDocument AsDocument => (ODBDocument)this;

        public virtual void Store(BinaryWriter storage)
        {
            byte[] storageBytes = ToStorage();

            storage.Write(storageTypeCode);
            storage.Write(storageBytes.Length);
            storage.Write(storageBytes, 0, storageBytes.Length);
        }

        public override int GetHashCode()
        {
            return Value.GetHashCode();
        }
        public override bool Equals(object obj)
        {
            if (obj is ODBValue)
            {
                ODBValue you = obj as ODBValue;
                return Value.Equals(you.Value);
            }
            return Value.Equals(obj);
        }



        //static Dictionary<Type, ODBValueFactory> valueFactories = new Dictionary<Type, ODBValueFactory>();
        //public static void RegisterValueFactory(Type type, ODBValueFactory factory)
        //{
        //    valueFactories.Add(type, factory);
        //}

        public static implicit operator ODBValue(ValueType v)
        {
            return ODBMapper.Default.MapValue(v);
        }
        public static implicit operator ODBValue(String v)
        {
            return ODBMapper.Default.MapValue(v);
        }

        public static ODBValue FromNative(object v)
        {
            return ODBMapper.Default.MapValue(v);
        }

        static Dictionary<int, ODBDeserialize> valueDeserializers = new Dictionary<int, ODBDeserialize>();
        public static void RegisterDeserializer(int storageTypeCode, ODBDeserialize deserialize)
        {
            valueDeserializers.Add(storageTypeCode, deserialize);
        }

        public static ODBValue Deserialize(byte[] buffer, ref int offset)
        {
            int storageTypeCode = BitConverter.ToInt32(buffer, offset);
            int storageLength = BitConverter.ToInt32(buffer, offset + 4);
            ODBValue value = valueDeserializers[storageTypeCode](buffer, offset + 8, storageLength);
            offset += 8 + storageLength;
            return value;
        }

        public static ODBValue Read(Stream stream)
        {
            int storageTypeCode = stream.ReadInteger();
            int storageLength = stream.ReadInteger();
            byte[] b = new byte[storageLength];
            stream.Read(b, 0, storageLength);

            return valueDeserializers[storageTypeCode](b, 0, storageLength);
        }

        public override string ToString()
        {
            return String.Format("[ODBValue Value={0}]", Value);
        }
    }
}