/**
 * @file    shellmatta_transport.h
 * @brief   transport layer functions of shellmatta
 * @author  Simon Fischer <fischer.simon.1991@gmail.com>
 */

#include "shellmatta_transport.h"

shellmatta_retCode_t shellmatta_handle_transport_fsm(shellmatta_transport_layer_t *transportLayer, char *data)
{
    switch (transportLayer->state)
    {
    case STATE_IDLE:
        if (SHELLMATTA_START_OF_HEADER == *data)
        {
            transportLayer->state = STATE_SOH;
        }
        else
        {
            transportLayer->state = STATE_PAYLOAD;
        }
        break;
    case STATE_SOH:
        transportLayer->state = STATE_PROTOCOL_VERSION;
        break;
    case STATE_PROTOCOL_VERSION:
        transportLayer->state = STATE_PACKET_TYPE;
        break;
    case STATE_PACKET_TYPE:
        transportLayer->state = STATE_PAYLOAD_LENGTH;
        break;
    case STATE_PAYLOAD_LENGTH:
        transportLayer->state = STATE_SOURCE;
        break;
    case STATE_SOURCE:
        transportLayer->state = STATE_DESTINATION;
        break;
    case STATE_DESTINATION:
        transportLayer->state = STATE_H2S_SEQUENCE_CNT;
        break;
    case STATE_H2S_SEQUENCE_CNT:
        transportLayer->state = STATE_S2H_SEQUENCE_CNT;
        break;
    case STATE_S2H_SEQUENCE_CNT:
        transportLayer->state = STATE_PAYLOAD;
        break;
    case STATE_PAYLOAD:
        transportLayer->state = STATE_CRC;
        break;
    case STATE_CRC:
        transportLayer->state = STATE_IDLE;
        transportLayer->h2s_sequenceCnt += 1;
        // TODO: incrementing both h2s and s2h doesn't make much sense, does it?
        transportLayer->s2h_sequenceCnt += 1; 
        break;
    
    default:
        break;
    }

    return SHELLMATTA_OK;
}