using System;
using System.Collections.Generic;
using System.Text;
using SafeMobileLib;

namespace SafeMobileLib.MessageDecoders
{
    public class ARSdecoder
    {
        private string SUID;
        private byte[] data;
        private DBsubsOperationManager DBsub;
        public Boolean isOFF = true;

        public ARSdecoder(string suid, byte[] data, DBsubsOperationManager DBsub)
        {
            SUID = suid;
            this.data = data;
            this.DBsub = DBsub;
            header_T reth = DecodePacket(data);
            switch (reth.pdu_type)
            {
                case 0x00: // registration
                    
                    goto case 0x0F;
                case 0x0F: // query reply
                    DBsub.updateSUStatus(suid.ToString(), 1);
                    isOFF = false;
                    break;

                case 0x01: // deregistration
                    DBsub.updateSUStatus(suid.ToString(), 0);
                    break;
                default: break;
            }

        }

        public ARSdecoder()
        {
           
        }

        public header_T DecodePacket(Byte[] data)
        {
            int i, pdata;
            Console.WriteLine("--------------------");

            pdata = (int)data[0];
            pdata <<= 8;
            pdata |= (int)data[1];

            // ----------------------------------------
            // parse header
            // ----------------------------------------
            header_T header = new header_T();
            header.ext = false;
            if ((data[2] & 0x80) != 0)
                header.ext = true;

            header.ack = false;
            if ((data[2] & 0x40) != 0)
                header.ack = true;

            header.priority = false;
            if ((data[2] & 0x20) != 0)
                header.priority = true;

            header.cntl = false;
            if ((data[2] & 0x10) != 0)
                header.cntl = true;

            header.pdu_type = (byte)(data[2] & 0x0F);

            Console.WriteLine("Header : ext=" + header.ext + " ack=" + header.ack + " priority=" + header.priority + " cntl=" + header.cntl + " type=" + header.pdu_type);
            switch (header.pdu_type)
            {
                case 0x00: Console.WriteLine("ARS Registration"); break;
                case 0x0F: Console.WriteLine("Query ACK"); break;
                case 0x01: Console.WriteLine("Deregistration message"); break;
                default: Console.WriteLine("Unknown ARS message"); break;
            }

            i = 3;
            if (i >= pdata + 2)
            {
                Console.WriteLine("--------------------");
                return header;
            }
            if (header.ext)
            {
                // read second header octet
                byte evt = data[i];
                evt &= 0x70;
                evt >>= 5;
                switch (evt)
                {
                    case 0: header.events = header_event.Unqualified_Event; break;
                    case 1: header.events = header_event.Initial_Event; break;
                    case 2: header.events = header_event.Refresh_Event; break;
                    default: header.events = header_event.UNKNOWN; break;
                }
                header.events = (header_event)evt;

                header.encoding = (byte)(data[i] & 0x0f);
                Console.WriteLine("HeaderExt : event=" + header.events + " encoding=" + header.encoding);
                i++;
            }
            if (i >= pdata + 2)
            {
                Console.WriteLine("--------------------");
                return header;
            }

            // ----------------------------------------
            // parse address len
            // ----------------------------------------
            int addr_len = data[i];
            i++;
            if (i >= pdata + 2)
            {
                Console.WriteLine("--------------------");
                return header;

            }

            i -= 2;
            Console.WriteLine("--------------------");
            return header;
        }

        //AUx
        public struct header_T
        {
            public bool ext, ack, priority, cntl;
            public byte pdu_type;
            public header_event events;
            public byte encoding;
        }
    }

    
}