#include "E22.h"
#include <string.h>

#define E22_AUX_TIMEOUT_MS  5000U

static UART_HandleTypeDef *e22_uart;

uint8_t E22_WaitAux(uint32_t timeout_ms)
{
    uint32_t tick_start = HAL_GetTick();

    while (HAL_GPIO_ReadPin(E22_AUX_GPIO_Port, E22_AUX_Pin) == GPIO_PIN_RESET)
    {
        if ((HAL_GetTick() - tick_start) >= timeout_ms)
        {
            return 0;
        }
    }

    return 1;
}

HAL_StatusTypeDef E22_Init(UART_HandleTypeDef *huart)
{
    e22_uart = huart;

    HAL_GPIO_WritePin(E22_M0_GPIO_Port, E22_M0_Pin, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(E22_M1_GPIO_Port, E22_M1_Pin, GPIO_PIN_RESET);

    if (E22_WaitAux(E22_AUX_TIMEOUT_MS) == 0U)
    {
        return HAL_TIMEOUT;
    }

    return HAL_OK;
}

HAL_StatusTypeDef E22_ReadConfiguration(uint8_t config[9])
{
    static const uint8_t command[3] = {0xC1U, 0x00U, 0x09U};
    uint8_t response[12] = {0U};
    HAL_StatusTypeDef status;

    if ((e22_uart == 0) || (config == 0))
    {
        return HAL_ERROR;
    }

    HAL_GPIO_WritePin(E22_M0_GPIO_Port, E22_M0_Pin, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(E22_M1_GPIO_Port, E22_M1_Pin, GPIO_PIN_SET);
    HAL_Delay(50U);
    if (E22_WaitAux(E22_AUX_TIMEOUT_MS) == 0U)
    {
        status = HAL_TIMEOUT;
        goto restore_normal_mode;
    }

    __HAL_UART_CLEAR_OREFLAG(e22_uart);
    __HAL_UART_FLUSH_DRREGISTER(e22_uart);
    status = HAL_UART_Transmit(e22_uart, (uint8_t *)command, sizeof(command), 500U);
    if (status != HAL_OK)
    {
        goto restore_normal_mode;
    }

    status = HAL_UART_Receive(e22_uart, response, sizeof(response), 1500U);
    if (status != HAL_OK)
    {
        goto restore_normal_mode;
    }

    if ((response[0] != 0xC1U) ||
        (response[1] != 0x00U) ||
        (response[2] != 0x09U))
    {
        status = HAL_ERROR;
        goto restore_normal_mode;
    }

    memcpy(config, &response[3], 9U);

restore_normal_mode:
    HAL_GPIO_WritePin(E22_M0_GPIO_Port, E22_M0_Pin, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(E22_M1_GPIO_Port, E22_M1_Pin, GPIO_PIN_RESET);
    HAL_Delay(50U);
    (void)E22_WaitAux(E22_AUX_TIMEOUT_MS);
    return status;
}

HAL_StatusTypeDef E22_Send(uint8_t *data, uint16_t len)
{
    if (e22_uart == 0)
    {
        return HAL_ERROR;
    }

    if (E22_WaitAux(E22_AUX_TIMEOUT_MS) == 0U)
    {
        return HAL_TIMEOUT;
    }

    HAL_StatusTypeDef status = HAL_UART_Transmit(e22_uart, data, len, 1000);
    if (status != HAL_OK)
    {
        return status;
    }

    if (E22_WaitAux(E22_AUX_TIMEOUT_MS) == 0U)
    {
        return HAL_TIMEOUT;
    }

    return HAL_OK;
}

HAL_StatusTypeDef E22_Receive(uint8_t *data, uint16_t len, uint32_t timeout_ms)
{
    if (e22_uart == 0)
    {
        return HAL_ERROR;
    }

    return HAL_UART_Receive(e22_uart, data, len, timeout_ms);
}