#include <string.h>
#include <stdint.h>
#include <stdio.h>
#include <stdbool.h>

#include "main.h"

UART_HandleTypeDef huart2;
I2C_HandleTypeDef hi2c1;

uint8_t data[2] = {0};

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_Init(void);
static void MX_I2C1_Init(void);


#ifdef __GNUC__
#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else
#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif /* __GNUC__ */

PUTCHAR_PROTOTYPE
{
    HAL_UART_Transmit(&huart2, (uint8_t *)&ch, 1, 0xFFFF);

    return ch;
}

int main(void)
{
    HAL_Init();
    SystemClock_Config();
    MX_GPIO_Init();
    MX_USART2_UART_Init();
    MX_I2C1_Init();

    data[0] = 1; // Config register
    if(HAL_I2C_Master_Transmit_IT(&hi2c1, (uint16_t)(0x48 << 1), data, 1) != HAL_OK) {
        printf("I2c tx failed.\r\n");
    }
    while(1) {};
}

void HAL_I2C_MasterTxCpltCallback(I2C_HandleTypeDef *hi2c)
{
    if(HAL_I2C_Master_Receive_IT(&hi2c1, (uint16_t)(0x48 << 1), data, 2) != HAL_OK) {
        printf("I2c rx failed.\r\n");
    }
}

void HAL_I2C_MasterRxCpltCallback(I2C_HandleTypeDef *hi2c)
{
    uint16_t config = (uint16_t)(data[0] << 8) | data[1];
    printf("ADS1115 config register: 0x%04x\r\n", config);
}

void SystemClock_Config(void)
{
    RCC_OscInitTypeDef RCC_OscInitStruct = {0};
    RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
    RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

    HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);

    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI|RCC_OSCILLATORTYPE_LSI;
    RCC_OscInitStruct.HSIState = RCC_HSI_ON;
    RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV1;
    RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
    RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV1;
    RCC_OscInitStruct.PLL.PLLN = 8;
    RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
    RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
    RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
    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_PLLCLK;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;

    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) {
        Error_Handler();
    }

    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART2 | RCC_PERIPHCLK_I2C1;
    PeriphClkInit.Usart2ClockSelection = RCC_USART2CLKSOURCE_PCLK1;
    if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK) {
        Error_Handler();
    }
}

static void MX_USART2_UART_Init(void)
{
    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();
    }
}

/**
  * @brief I2C1 Initialization Function
  * @param None
  * @retval None
  */
static void MX_I2C1_Init(void)
{

  /* USER CODE BEGIN I2C1_Init 0 */

  /* USER CODE END I2C1_Init 0 */

  /* USER CODE BEGIN I2C1_Init 1 */

  /* USER CODE END I2C1_Init 1 */
  hi2c1.Instance = I2C1;
  hi2c1.Init.Timing = 0x10707DBC;
  hi2c1.Init.OwnAddress1 = 0;
  hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2 = 0;
  hi2c1.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
  hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c1) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure Analogue filter
  */
  if (HAL_I2CEx_ConfigAnalogFilter(&hi2c1, I2C_ANALOGFILTER_ENABLE) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure Digital filter
  */
  if (HAL_I2CEx_ConfigDigitalFilter(&hi2c1, 0) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN I2C1_Init 2 */

  /* USER CODE END I2C1_Init 2 */

}

static void MX_GPIO_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStruct = {0};

    __HAL_RCC_GPIOC_CLK_ENABLE();
    __HAL_RCC_GPIOF_CLK_ENABLE();
    __HAL_RCC_GPIOA_CLK_ENABLE();

    HAL_GPIO_WritePin(LED_GREEN_GPIO_Port, LED_GREEN_Pin, GPIO_PIN_RESET);

    GPIO_InitStruct.Pin = LED_GREEN_Pin;
    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(LED_GREEN_GPIO_Port, &GPIO_InitStruct);
}

void Error_Handler(void)
{
    __disable_irq();
    while (1) {
    }
}