using System;
using ln.json.mapping;
using ln.logging;
using ln.type;

namespace ln.ethercat
{
    public class SDO
    {

        public static SDO Create(ECMaster ecMaster, SDOAddr address)
        {
            SDO sdo = new SDO(ecMaster, address);
            if (address.SubIndex == 0)
            {
                if (ECMBind.ecmbind_read_objectdescription(address.Slave, address.Index, (int slave, int index, ECDataTypes dataType, ECObjectCodes objectCode, int maxsub, String name)=>{
                    sdo.DataType = dataType;
                    sdo.ObjectCode = objectCode;
                    sdo.MaxSubIndex = maxsub;
                    sdo.Name = name;
                }) <= 0)
                {
                    Logging.Log(LogLevel.WARNING, "cannot create SDO instance for {0}. not found.", address);
                    return null;
                }
            } else {
                if (ECMBind.ecmbind_read_objectdescription_entry((ushort)address.Slave, (ushort)address.Index, (ushort)address.SubIndex, (int slave, int index, ECDataTypes dataType, ECObjectCodes objectCode, int maxsub, String name)=>{
                    sdo.DataType = dataType;
                    sdo.MaxSubIndex = -1;
                    sdo.Name = name;
                }) <= 0)
                {
                    Logging.Log(LogLevel.WARNING, "cannot create SDO instance for {0}. not found.", address);
                    return null;
                }
            }
            return sdo;
        }

        public SDOAddr Address { get; }
        public string Name { get; private set; }

        public ECDataTypes DataType { get; set; }
        public ECObjectCodes ObjectCode { get; set; }
        public int MaxSubIndex { get; set; }

        public bool IsPartOfPDO => ECMaster.TryGetPDO(Address, out PDO pdo);

        byte[] rawData;
        public byte[] RawData {
            get {
                if (ECMaster.TryGetPDO(Address, out PDO pdo))
                {
                    if ((rawData == null) || (rawData.Length != pdo.ByteLength))
                        rawData = new byte[pdo.ByteLength];

                    ECMBind.ecmbind_iomap_get(pdo.AddressOffset, rawData, pdo.ByteLength);
                } else {
                    ECMaster.ReadSDO(Address, out rawData);
                }
                return rawData;
            }
            set => rawData = value;
        }
        public object Value {
            get => ECDataTypeConverter.ConvertFromEthercat(DataType ,RawData);
            set => throw new NotImplementedException();
        }

        ECMaster ECMaster { get; }

        SDO(ECMaster ecMaster, SDOAddr address)
        {
            ECMaster = ecMaster;
            Address = address;
        }

        public override string ToString()
        {
            return string.Format("[SDO Slave={0} Index={1:X4}.{7} MaxSubindex={2} ObjectCode={5} DataType={3} Name={4} RawData={6}]", Address.Slave, Address.Index, MaxSubIndex, DataType, Name, ObjectCode, RawData?.ToHexString(), Address.SubIndex);
        }

        public override bool Equals(object obj) => (obj is SDO other) && Address.Equals(other.Address);
        public override int GetHashCode() => Address.GetHashCode();

        public T GetValue<T>() => Cast.To<T>(Value);

    }

}