#include "modbus_rtu_master.h"

MODBUS_MASTER mod_master;

void modbus_rtu_master_init(void)
{
    mod_master.target_id = 0x00;
    mod_master.command_code = 0x00;
    mod_master.start_address = 0x0000;
    mod_master.register_num = 0x0000;
    mod_master.crc16 = 0x0000;
    mod_master.byte_num = 0;
    memset(mod_master.data_tx_value8, 0, TX_DATA_MAX);
    memset(mod_master.data_tx_value16, 0, TX_DATA_MAX);
    memset(mod_master.data_tx, 0, TX_BUFF_MAX);
    memset(mod_master.data_rx, 0, RX_BUFF_MAX);
    mod_master.data_tx_len = 0;
    mod_master.data_rx_len = 0;
    mod_master.rx_error_message = RX_ERROR_NONE;
    mod_master.tx_error_message = TX_ERROR_NONE;
    mod_master.timeout = 1000;
    mod_master.rx_flag = RX_NONE;
    mod_master.tx_flag = TX_NONE;
}

void modbus_rtu_master_load(void)
{
    mod_master.data_tx[0] = mod_master.target_id;
    mod_master.data_tx[1] = mod_master.command_code;
    memset(mod_master.data_rx, 0, sizeof(mod_master.data_rx));

    switch (mod_master.data_tx[1])
    {
        //读四种寄存器的格式一致
        case ReadCoilState:
        {
            //注释break，直接向下穿透
        }
        //break;

        case ReadDisInputState:
        {
            //注释break，直接向下穿透
        }
        //break;

        case ReadHoldReg:
        {
            //注释break，直接向下穿透
        }
        //break;

        case ReadInputReg:
        {
            mod_master.data_tx[2] = (uint8_t)(mod_master.start_address >> 8);
            mod_master.data_tx[3] = (uint8_t)(mod_master.start_address & 0x00FF); 
            mod_master.data_tx[4] = (uint8_t)(mod_master.register_num >> 8);
            mod_master.data_tx[5] = (uint8_t)(mod_master.register_num & 0x00FF); 
            mod_master.crc16 = ModbusCRC16(mod_master.data_tx, 6);
            mod_master.data_tx[6] = (uint8_t)(mod_master.crc16 & 0x00FF); 
            mod_master.data_tx[7] = (uint8_t)(mod_master.crc16 >> 8);

            mod_master.data_tx_len = 8;
        }
        break;

        case WriteSingleCoil:
        {
            mod_master.data_tx[2] = (uint8_t)(mod_master.start_address >> 8);
            mod_master.data_tx[3] = (uint8_t)(mod_master.start_address & 0x00FF); 
            mod_master.data_tx[4] = (uint8_t)(mod_master.data_tx_value8[0] >> 8);
            mod_master.data_tx[5] = (uint8_t)(mod_master.data_tx_value8[0] & 0x00FF); 
            mod_master.crc16 = ModbusCRC16(mod_master.data_tx, 6);
            mod_master.data_tx[6] = (uint8_t)(mod_master.crc16 & 0x00FF); 
            mod_master.data_tx[7] = (uint8_t)(mod_master.crc16 >> 8);

            mod_master.data_tx_len = 8;
        }
        break;

        case WriteSingleReg:
        {
            mod_master.data_tx[2] = (uint8_t)(mod_master.start_address >> 8);
            mod_master.data_tx[3] = (uint8_t)(mod_master.start_address & 0x00FF); 
            mod_master.data_tx[4] = (uint8_t)(mod_master.data_tx_value16[0] >> 8);
            mod_master.data_tx[5] = (uint8_t)(mod_master.data_tx_value16[0] & 0x00FF); 
            mod_master.crc16 = ModbusCRC16(mod_master.data_tx, 6);
            mod_master.data_tx[6] = (uint8_t)(mod_master.crc16 & 0x00FF); 
            mod_master.data_tx[7] = (uint8_t)(mod_master.crc16 >> 8);

            mod_master.data_tx_len = 8;
        }
        break;

        case WriteMultiCoil:
        {
            if( mod_master.register_num % 8  )
            {
                //线圈数量不为8的倍数时，字节数 == （线圈数量/8 + 1）
                if( (mod_master.register_num/8 + 1) != mod_master.byte_num )
                {
                    mod_master.tx_error_message = TX_ERROR_COIL_NUM;
                    return;
                }
            }
            else
            {
                //线圈数量为8的倍数时，字节数 == 线圈数量/8
                if( (mod_master.register_num/8) != mod_master.byte_num )
                {
                    mod_master.tx_error_message = TX_ERROR_COIL_NUM;
                    return;
                }
            }

            mod_master.data_tx[2] = (uint8_t)(mod_master.start_address >> 8);
            mod_master.data_tx[3] = (uint8_t)(mod_master.start_address & 0x00FF); 
            mod_master.data_tx[4] = (uint8_t)(mod_master.register_num >> 8);
            mod_master.data_tx[5] = (uint8_t)(mod_master.register_num & 0x00FF); 
            mod_master.data_tx[6] = mod_master.byte_num;
            for(uint8_t i = 1; i <= mod_master.byte_num; i++ )
            {
                mod_master.data_tx[6 + i] = mod_master.data_tx_value8[i - 1];
            }
            mod_master.crc16 = ModbusCRC16(mod_master.data_tx, 7 + mod_master.byte_num);
            mod_master.data_tx[7 + mod_master.byte_num] = (uint8_t)(mod_master.crc16 & 0x00FF); 
            mod_master.data_tx[8 + mod_master.byte_num] = (uint8_t)(mod_master.crc16 >> 8);

            mod_master.data_tx_len = 8 + mod_master.byte_num + 1;
        }
        break;

        case WriteMultiReg:
        {
            if( (mod_master.register_num * 2) != mod_master.byte_num )
            {
                //字节数 == （寄存器数量*2）
                mod_master.tx_error_message = TX_ERROR_HOLDREG_NUM;
                return;
            }

            mod_master.data_tx[2] = (uint8_t)(mod_master.start_address >> 8);
            mod_master.data_tx[3] = (uint8_t)(mod_master.start_address & 0x00FF); 
            mod_master.data_tx[4] = (uint8_t)(mod_master.register_num >> 8);
            mod_master.data_tx[5] = (uint8_t)(mod_master.register_num & 0x00FF); 
            mod_master.data_tx[6] = mod_master.byte_num;
            for(uint8_t i = 1; i <= mod_master.byte_num; i++ )
            {
                mod_master.data_tx[6 + i] = mod_master.data_tx_value16[ (i - 1)/2 ] >> ( 8*(i%2) );
            }
            mod_master.crc16 = ModbusCRC16(mod_master.data_tx, 7 + mod_master.byte_num);
            mod_master.data_tx[7 + mod_master.byte_num] = (uint8_t)(mod_master.crc16 & 0x00FF); 
            mod_master.data_tx[8 + mod_master.byte_num] = (uint8_t)(mod_master.crc16 >> 8);

            mod_master.data_tx_len = 8 + mod_master.byte_num + 1;
        }
        break;
    
        default:
        {
            mod_master.tx_error_message = TX_ERROR_WRONG_CMD;
        }
        break;
    }
}

void modbus_rtu_master_send(void)
{
    if(mod_master.tx_error_message == TX_ERROR_NONE)
    {
        mod_master.rx_flag = TX_WAITING;

        //将准备好的数据发送至从设备
        memcpy(scom2_rs485.tx_buff, mod_master.data_tx, mod_master.data_tx_len);
        scom2_rs485.tx_len = mod_master.data_tx_len;
        scom2_rs485.tx_flag = TRUE;

        if(scom2_rs485.tx_flag == TRUE)
        {
            scom2_rs485.tx_flag = FALSE;

            //将数据发送至上位机
            HAL_UART_Transmit_DMA(&huart2, scom2_rs485.tx_buff, scom2_rs485.tx_len);
        }

        //在发送回调中判断发送是否完成
        sig_trans = TRANS_MODBUS_SIG_TO_SLAVE;
    }
}

void modbus_rtu_master_analysis(void)
{
    if(scom2_rs485.rx_len > RX_BUFF_MAX)
    {
        mod_master.rx_error_message = RX_ERROR_OVERFLOW;
        return;
    }

    mod_master.data_rx_len = scom2_rs485.rx_len;
    memcpy(mod_master.data_rx, scom2_rs485.rx_buff, mod_master.data_rx_len);

    if(mod_master.data_rx[0] != mod_master.target_id)
    {
        mod_master.rx_error_message = RX_ERROR_WRONG_ID;
        return;
    }

    if(mod_master.data_rx[1] <= 0x80)
    {
        //收到的是正常响应
    }
    else
    {
        //收到的是异常响应
        ex_message = (eMBException)mod_master.data_rx[2];
    }


    mod_master.rx_flag = RX_OK;
}