#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include "stm32c0xx_hal.h"

// LED1 -> PA2
#define LED1_PORT               GPIOA
#define LED1_PIN                GPIO_PIN_2
#define LED1_CLK_ENABLE()       __HAL_RCC_GPIOA_CLK_ENABLE()

// LED2 -> PB12
#define LED2_PORT               GPIOB
#define LED2_PIN                GPIO_PIN_12
#define LED2_CLK_ENABLE()       __HAL_RCC_GPIOB_CLK_ENABLE()

UART_HandleTypeDef huart2;

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

int main(void)
{
    HAL_Init();
    SystemClock_Config();

    MX_GPIO_Init();
    MX_USART2_UART_Init();

    char rxBuffer[32];
    int idx = 0;
    char received;

    printf("USART2 ready. Type commands:\r\n");

    while (1)
    {
        if (HAL_UART_Receive(&huart2, (uint8_t *)&received, 1, HAL_MAX_DELAY) == HAL_OK)
        {
            // echo (показываем то, что набираем в терминале)
            HAL_UART_Transmit(&huart2, (uint8_t *)&received, 1, HAL_MAX_DELAY);

            if (received == '\n' || received == '\r')
            {
                if (idx > 0)   // есть команда
                {
                    rxBuffer[idx] = '\0';
                    idx = 0;

                    if (strcmp(rxBuffer, "Left_on") == 0)
                    {
                        HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_SET);
                    }
                    else if (strcmp(rxBuffer, "Left_off") == 0)
                    {
                        HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_RESET);
                    }
                    else if (strcmp(rxBuffer, "Right_on") == 0)
                    {
                        HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, GPIO_PIN_SET);
                    }
                    else if (strcmp(rxBuffer, "Right_off") == 0)
                    {
                        HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, GPIO_PIN_RESET);
                    }
                    else
                    {
                        printf("Unknown cmd: %s\n", rxBuffer);
                    }
                }
            }
            else
            {
                if (idx < sizeof(rxBuffer) - 1)
                {
                    rxBuffer[idx++] = received;
                }
            }
        }
    }
}

/* ================= GPIO INIT ================= */
static void MX_GPIO_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStruct = {0};

    // LED1 PA2
    LED1_CLK_ENABLE();
    GPIO_InitStruct.Pin = LED1_PIN;
    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    HAL_GPIO_Init(LED1_PORT, &GPIO_InitStruct);

    // LED2 PB12
    LED2_CLK_ENABLE();
    GPIO_InitStruct.Pin = LED2_PIN;
    HAL_GPIO_Init(LED2_PORT, &GPIO_InitStruct);
}

/* ================= USART2 INIT ================= */
static void MX_USART2_UART_Init(void)
{
    __HAL_RCC_GPIOA_CLK_ENABLE();
    __HAL_RCC_USART2_CLK_ENABLE();

    GPIO_InitTypeDef GPIO_InitStruct = {0};

    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;
    huart2.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
    huart2.Init.ClockPrescaler = UART_PRESCALER_DIV1;
    huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;

    if (HAL_UART_Init(&huart2) != HAL_OK)
    {
        Error_Handler();
    }
}

/* ================= SYSTEM CLOCK ================= */
void SystemClock_Config(void)
{
    RCC_OscInitTypeDef RCC_OscInitStruct = {0};
    RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
    RCC_OscInitStruct.HSIState = RCC_HSI_ON;
    RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV1;
    RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
    {
        Error_Handler();
    }

    RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
                                | RCC_CLOCKTYPE_PCLK1;
    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
    RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV1;
    RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV1;

    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
    {
        Error_Handler();
    }
}

/* ================== ERROR HANDLER ================== */
void Error_Handler(void)
{
    while (1) {}
}

/* printf redirection */
int _write(int file, char *ptr, int len)
{
    HAL_UART_Transmit(&huart2, (uint8_t *)ptr, len, HAL_MAX_DELAY);
    return len;
}