/**
 * @file NbusBridge.cpp
 * @brief Implemetnácia modulu nBus Brige
 * @date Mar 7, 2025
 * @author Juraj Dudak
 */

#include "NbusBridge.h"


static const uint8_t __crc8x_table[] = {
    0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15, 0x38, 0x3F, 0x36, 0x31, 0x24, 0x23, 0x2A, 0x2D, 0x70, 0x77, 0x7E,
    0x79, 0x6C, 0x6B, 0x62, 0x65, 0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D, 0xE0, 0xE7, 0xEE, 0xE9, 0xFC, 0xFB,
    0xF2, 0xF5, 0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD, 0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85, 0xA8,
    0xAF, 0xA6, 0xA1, 0xB4, 0xB3, 0xBA, 0xBD, 0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2, 0xFF, 0xF8, 0xF1, 0xF6,
    0xE3, 0xE4, 0xED, 0xEA, 0xB7, 0xB0, 0xB9, 0xBE, 0xAB, 0xAC, 0xA5, 0xA2, 0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D,
    0x9A, 0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32, 0x1F, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0D, 0x0A, 0x57, 0x50,
    0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42, 0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A, 0x89, 0x8E, 0x87, 0x80, 0x95,
    0x92, 0x9B, 0x9C, 0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4, 0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC,
    0xC1, 0xC6, 0xCF, 0xC8, 0xDD, 0xDA, 0xD3, 0xD4, 0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C, 0x51, 0x56, 0x5F,
    0x58, 0x4D, 0x4A, 0x43, 0x44, 0x19, 0x1E, 0x17, 0x10, 0x05, 0x02, 0x0B, 0x0C, 0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A,
    0x33, 0x34, 0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B, 0x76, 0x71, 0x78, 0x7F, 0x6A, 0x6D, 0x64, 0x63, 0x3E,
    0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B, 0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13, 0xAE, 0xA9, 0xA0, 0xA7,
    0xB2, 0xB5, 0xBC, 0xBB, 0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83, 0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC,
    0xCB, 0xE6, 0xE1, 0xE8, 0xEF, 0xFA, 0xFD, 0xF4, 0xF3};

uint8_t NbusBridge::_crc8x_fast(void const *mem, uint16_t len)
{
    uint8_t crc = 0;
    uint8_t const *data = (uint8_t *)mem;
    if (data == nullptr)
        return 0xff;
    crc &= 0xff;
    while (len--)
        crc = __crc8x_table[crc ^ *data++];
    return crc;
}

void NbusBridge::setCommunicator(NbusCommunicator *nc)
{
    if (nc == nullptr)
    {
        while (1)
        {
            __NOP();
        }
    }

    _communicator = nc;
    _num_slaves = 0;
    _run_state = STATE_STOPPED;
    _pdu.sa = BROADCAST_ADDRESS;
}


/**
 * Spustí scan internej nbus siete.
 * Posiela requesty pre celý adresný priestor ako ECHO paket.
 * Výsledok je uložený interne. K jednotlivým slave-om sa dá dostať cez metódu getSlave(index), kde 0<=index<num_slaves
 */
void NbusBridge::scan()
{
    HAL_GPIO_WritePin(GPIOB, GPIO_PIN_3, GPIO_PIN_SET);

    _num_slaves = 0;

    DataFrame *response_frame;
    uint8_t   *response_raw;
    Nbus_PDU_t   pdu = {SLAVE_ADDRESS_MODULE, SLAVE_ADDRESS_MODULE, FC_ECHO};
    uint8_t    data[] = ECHO_SCAN_DATA;
    uint8_t    slave_index = 0;

    for (uint32_t i = 1; i < MAX_SLAVES; i++)
    {
        _slave_adress[i] = 0;
    }

    for (uint32_t i = 1; i < MAX_SLAVES; i++)
    {
        HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_3);
        pdu.ma = i;
        response_frame = _communicator->sendAndReceive(&pdu, data, ECHO_SCAN_LENGTH);

        if (!response_frame->IsEmpty())
        {
            response_raw = response_frame->GetFrame();

            if (DATA0_TX_ADDRESS(response_raw + 0) == ECHO_SCAN_CHAR0 && DATA0_TX_ADDRESS(response_raw + 1) == ECHO_SCAN_CHAR1 &&
            	DATA0_TX_ADDRESS(response_raw + 2) == ECHO_SCAN_CHAR2 && DATA0_TX_ADDRESS(response_raw + 3) == ECHO_SCAN_CHAR3)
            {
                _num_slaves++;
                _slaves[i].setAddress(i);
                _slaves[i].setCommunicator(_communicator);
                _slave_adress[slave_index++] = i;
                _slaves[i].nbusSlaveCmd_getSensorCnt(true); 	// retrieve sensor count for each slave
            }
        }
    }

    HAL_GPIO_WritePin(GPIOB, GPIO_PIN_3, GPIO_PIN_RESET);
}

/**
 * @brief Vráti inštanciu index-teho zdetegovaného nBus slave.
 * @return Smerník na existujúc NbusBridge alebo NULL
 */
NbusSlave *NbusBridge::getSlave(uint8_t index)
{
    if (index >= 0 && index < MAX_SLAVES)
    {
        if (_slaves[index].isActive())
        {
            return &_slaves[index];
        }
    }

    return nullptr;
}

/**
 * Vráti počet detegovaných nBus slave modulov na internej zbernici.
 * @return počet nBus slave zariadení.
 */
uint8_t NbusBridge::getNumSlaves()
{
    return _num_slaves;
}

/**
 * Na internú zbernicu odošle Broadcast request "START"
 */
void NbusBridge::broadcastStart()
{
    _pdu.fc = FC_START;
    _pdu.ma = BROADCAST_ADDRESS;
    _communicator->send(&_pdu, nullptr, 0);
    _run_state = STATE_RUNNING;
}

/**
 * Na internú zbernicu odošle Broadcast request "STOP"
 */
void NbusBridge::broadcastStop()
{
    _pdu.fc = FC_STOP;
    _pdu.ma = BROADCAST_ADDRESS;
    _communicator->send(&_pdu, nullptr, 0);
    _run_state = STATE_TO_STOP;
}

/**
 * Spracovanie broadcast requestu.
 * Inplementované funkcie:
 * - FC_STOP
 * - FC_START
 */
void NbusBridge::process_broadcast(uint8_t *rxFrame)
{
    switch (FUNCTION_RX_CODE(rxFrame))
    {

    case FC_STOP: /* 2 */
        this->broadcastStop();
        break;

    case FC_START: /* 3 */
        this->broadcastStart();
        break;

    default:; // nothing
    }
}

/**
 * Spracovanie requestu pre bridge.
 * Implementované funkcie:
 * - FC_SLAVES
 *   Formát odpovede: [senzor_idenx:sensor_address,]
 * - FC_RESET
 * 	 Odpoveď: kópia požiadavky
 * - FC_INFO
 * 	 Odpoved: XXXYYYZZZ, kde X-verzia FW, Y-použitá platfoma MCU, Z-verzia HW (formát: ASCII)
 * - FC_ECHO
 * 	 Odpoveď: kópia požiadavky
 */
void NbusBridge::process_bridge_request(uint8_t *rxFrame, uint8_t size)
{
	switch (FUNCTION_RX_CODE(rxFrame))
    {
    case FC_ECHO: /* 1 */
    	_master_frame.AddArray(&DATA0_RX_ADDRESS(rxFrame), size  - RX_META_SIZE);
        break;

    case FC_RESET: /* 9 */
	{
        _scan_request = 1;
        // send same frame back
    	_master_frame.AddArray(&DATA0_RX_ADDRESS(rxFrame), size  - RX_META_SIZE);
    }
    break;

    case FC_DATA: /* 11 */
    	_worker_frame_ptr = bridge_getData();
    	break;

    case FC_INFO: /* 0xE => 15 */
    	_worker_frame_ptr = bridge_getInfo();
        break;

    case FC_SLAVES: /* 0x10 => 16 */
       	_worker_frame_ptr = bridge_getSlaves();
        break;

    default:
      	_worker_frame_ptr = bridge_setErrResponse(ILLEGAL_FUNCTION);
    }

	_communicator->sendToMaster(_worker_frame_ptr);
}

void NbusBridge::process_slave_request(uint8_t *rxFrame, uint8_t size)
{
    NbusSlave *selected_slave = getSlave(MODULE_RX_ADDRESS(rxFrame));

    if (selected_slave == nullptr)
    {
    	_worker_frame_ptr = bridge_setErrResponse(ILLEGAL_DEVICE_ADDRESS);
    }

    _raw_data_frame.Init();
    _raw_data_frame.AddUint8(size);
    _raw_data_frame.AddArray(rxFrame, size);
    _raw_data_frame.Commit();

    _worker_frame_ptr = selected_slave->nbusSlaveCmd_processRequest(&_raw_data_frame);
    _communicator->sendToMaster(_worker_frame_ptr);
}

/**
 * Pripraví informáciu o všetkcýh nBus slave moduloch
 */
DataFrame* NbusBridge::bridge_getSlaves()
{
	_master_frame.Init();
	_master_frame.AddUint8(BROADCAST_ADDRESS);
	_master_frame.AddUint8(BRIDGE_ADDRESS);
	_master_frame.AddUint8(FC_SLAVES);

	for (uint8_t i = 0; i < _num_slaves; i++)
    {
		_master_frame.AddInt8(i + 1);
		_master_frame.AddInt8(_slave_adress[i]);
    }

	_master_frame.Commit();

	return &_master_frame;
}

DataFrame * NbusBridge::bridge_getInfo()
{
	_master_frame.Init();
	_master_frame.AddUint8(BROADCAST_ADDRESS);
	_master_frame.AddUint8(BRIDGE_ADDRESS);
	_master_frame.AddUint8(FC_INFO);
	_master_frame.AddArray((uint8_t *)BRIDGE_INFO_VERSION, 3);
	_master_frame.AddArray((uint8_t *)BRIDGE_INFO_HW_FAMILY, 3);
	_master_frame.AddArray((uint8_t *)BRIDGE_INFO_HW_VERSION, 3);
	_master_frame.Commit();

	return &_master_frame;
}

DataFrame * NbusBridge::bridge_getData()
{
	NbusSlave * slave_ptr = nullptr;

	_raw_data_frame.Init();
	_raw_data_frame.AddHeader(TYPE_HEADER_2B);
	_raw_data_frame.AddInt32(HAL_GetTick());

	for (uint32_t i = 0; i < _num_slaves; i++)
	{
		slave_ptr = getSlave(_slave_adress[i]);
		if (slave_ptr != nullptr)
		{
			_raw_data_frame.AddInt8(slave_ptr->getModuleAddress());
			_worker_frame_ptr = slave_ptr->nbusSlaveCmd_getData();
			_raw_data_frame.AddArray(&DATA0_RX_ADDRESS(_worker_frame_ptr->GetFrame() + 1), _worker_frame_ptr->GetLength() - (RX_META_SIZE + 1));
		}
	}

	_raw_data_frame.AddInt8(BRIDGE_TERMINATOR);
	_raw_data_frame.AddInt8(BRIDGE_TERMINATOR);
	_raw_data_frame.Commit();

	return &_raw_data_frame;
}

DataFrame * NbusBridge::bridge_setErrResponse(Nbus_EC_e ec)
{
	_master_frame.Init();
	_master_frame.AddUint8(_pdu.ma);
	_master_frame.AddUint8(_pdu.sa);
	_master_frame.AddUint8(SET_ERR_RESPONSE(_pdu.fc));
	_master_frame.AddUint8(ec);
	_master_frame.Commit();

	return &_master_frame;
}

/**
 * Implementácia rozhrania nBus.
 */
void NbusBridge::processRequest(uint8_t *rxFrame, uint8_t size)
{
    uint8_t crcC = _crc8x_fast(rxFrame, size - 1);

    if (crcC != rxFrame[size - 1])
    {
        return;
    }

    _pdu.ma = rxFrame[0];
    _pdu.sa = rxFrame[1];
    _pdu.fc = (Nbus_FC_e)rxFrame[2];

    if (_pdu.ma == BROADCAST_ADDRESS)
    {
        if (_pdu.sa == BRIDGE_ADDRESS)
        {
            process_bridge_request(rxFrame, size);
        }
        else
        {
            process_broadcast(rxFrame);
        }
    }
    else
    {
        process_slave_request(rxFrame, size);
    }
}

/**
 * Implementácia stavu STATE_RUNNING.
 * V tomto stave je spustené automatické odčítanie údajov zo všetkých slave/všetkých senzorov.
 * Dáta sa v dávke (za všetky slavy) odosielajú na Master.
 */
void NbusBridge::processRunningState()
{

    if (_scan_request == 1)
    {
        _scan_request = 0;
        this->scan();
    }

    if (_run_state == STATE_STOPPED)
    {
        return;
    }

    if (_run_state == STATE_TO_STOP)
    {
        HAL_GPIO_WritePin(GPIOB, GPIO_PIN_3, GPIO_PIN_RESET);
        _run_state = STATE_STOPPED;
        return;
    }

    HAL_GPIO_WritePin(GPIOB, GPIO_PIN_3, GPIO_PIN_SET);

    _worker_frame_ptr = bridge_getData();

    // TODO problem: v stavi RUNNING pride STOP prikaz, ale ten sa nespracuje, pretoze bezi obsluha tejto funkcie.
    if (_run_state == STATE_RUNNING)
    {
        _communicator->sendToMaster(_worker_frame_ptr);
    }

    /// TODO toto sa MI NEPACI, TREBA VYRIESIT INAK!!!!!!
    HAL_Delay(50); // TREBA VYSKUSAT
}