#include "stm32c0xx_hal.h"

UART_HandleTypeDef huart2;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_Init(void);

int main(void)
{
    uint8_t rxBuffer;

    HAL_Init();

    SystemClock_Config();

    MX_GPIO_Init();
    MX_USART2_UART_Init();

    HAL_UART_Transmit(&huart2,
                      (uint8_t*)"Start Program\r\n",
                      15,
                      100);

    while (1)
    {
        if(HAL_UART_Receive(&huart2, &rxBuffer, 1, HAL_MAX_DELAY) == HAL_OK)
        {
            switch(rxBuffer)
            {
                case '1':
                    HAL_GPIO_WritePin(GPIOA,
                                      GPIO_PIN_5,
                                      GPIO_PIN_SET);

                    HAL_UART_Transmit(&huart2,
                                      (uint8_t*)"LED ON\r\n",
                                      8,
                                      100);
                    break;

                case '2':
                    HAL_GPIO_WritePin(GPIOA,
                                      GPIO_PIN_5,
                                      GPIO_PIN_RESET);

                    HAL_UART_Transmit(&huart2,
                                      (uint8_t*)"LED OFF\r\n",
                                      9,
                                      100);
                    break;

                case '\r':
                case '\n':
                    break;

                default:
                    HAL_UART_Transmit(&huart2,
                                      (uint8_t*)"Unknown Command\r\n",
                                      17,
                                      100);
                    break;
            }
        }
    }
}

static void MX_GPIO_Init(void)
{
    __HAL_RCC_GPIOA_CLK_ENABLE();

    GPIO_InitTypeDef GPIO_InitStruct = {0};

    GPIO_InitStruct.Pin = GPIO_PIN_5;
    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;

    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}

static void MX_USART2_UART_Init(void)
{
    __HAL_RCC_USART2_CLK_ENABLE();
    __HAL_RCC_GPIOA_CLK_ENABLE();

    GPIO_InitTypeDef GPIO_InitStruct = {0};

    GPIO_InitStruct.Pin = GPIO_PIN_2 | GPIO_PIN_3;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF1_USART2;

    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    huart2.Instance = USART2;
    huart2.Init.BaudRate = 115200;
    huart2.Init.WordLength = UART_WORDLENGTH_8B;
    huart2.Init.StopBits = UART_STOPBITS_1;
    huart2.Init.Parity = UART_PARITY_NONE;
    huart2.Init.Mode = UART_MODE_TX_RX;
    huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
    huart2.Init.OverSampling = UART_OVERSAMPLING_16;

    HAL_UART_Init(&huart2);
}

void SystemClock_Config(void)
{
}