#include "stm32c0xx_hal.h"
#include "stm32c0xx_hal_uart.h"
#include <stdio.h>
#include <string.h>

// Function prototypes
void SystemClock_Config(void);
void UART_Init(void);
void UART1_Init(void);
void EXTI_Init(void);

UART_HandleTypeDef huart1;
UART_HandleTypeDef huart2;
char buffer[4];

int main() {
  HAL_Init();
  SystemClock_Config();
  UART_Init();
  UART1_Init();

  printf("System initialized.\n");


  while (1) {
    HAL_UART_Transmit(&huart1, (uint8_t *)"data", strlen("data"), HAL_MAX_DELAY);
    HAL_UART_Receive(&huart2, (uint8_t *)buffer, sizeof(buffer), 100);
  }
}

// System Clock Configuration
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.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  HAL_RCC_OscConfig(&RCC_OscInitStruct);

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK |
                                RCC_CLOCKTYPE_PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);
  __HAL_RCC_USART2_CLK_ENABLE();
  __HAL_RCC_USART1_CLK_ENABLE();

  __HAL_RCC_GPIOA_CLK_ENABLE();
}

// UART Initialization
void UART_Init(void) {
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  // Configure PA2 (TX) and PA3 (RX) for USART2
  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_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF1_USART2;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  huart2.Instance = USART2;
  huart2.Init.BaudRate = 9600;
  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_8;
  HAL_NVIC_SetPriority(USART2_IRQn, 1, 0) ;
  HAL_NVIC_EnableIRQ(USART2_IRQn) ;

  if (HAL_UART_Init(&huart2) != HAL_OK) {
    while (1);
  }

  //HAL_UART_Receive_IT(&huart2, (uint8_t *)buffer, sizeof(buffer));
}

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) {
  if (huart->Instance == USART2)
  {
    printf("received!");
    HAL_UART_Receive_IT(&huart2, (uint8_t *)buffer, sizeof(buffer));
  }
}

void USART2_IRQHandler(void) {
  HAL_UART_IRQHandler(&huart2);
}



void UART1_Init(void) {
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  // Configure PA9 (TX) and PA10 (RX) for USART1
  GPIO_InitStruct.Pin = GPIO_PIN_9 | GPIO_PIN_10;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF1_USART1;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  huart1.Instance = USART1;
  huart1.Init.BaudRate = 9600;
  huart1.Init.WordLength = UART_WORDLENGTH_8B;
  huart1.Init.StopBits = UART_STOPBITS_1;
  huart1.Init.Parity = UART_PARITY_NONE;
  huart1.Init.Mode = UART_MODE_TX_RX;
  huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart1.Init.OverSampling = UART_OVERSAMPLING_8;

  if (HAL_UART_Init(&huart1) != HAL_OK) {
    while (1);
  }
}