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

// ST Nucleo Green user LED (PA5)
#define LED_PORT                GPIOA
#define LED_PIN                 GPIO_PIN_5
// Rows defines
#define ROWS_PORT   GPIOB
#define ROWS_PINS   4
#define ROW_A_PIN   GPIO_PIN_4
#define ROW_B_PIN   GPIO_PIN_5
#define ROW_C_PIN   GPIO_PIN_6
#define ROW_D_PIN   GPIO_PIN_7
// Columns defines
#define COLS_PORT   GPIOD
#define COLS_PINS   3
#define COL1_PIN    GPIO_PIN_0
#define COL2_PIN    GPIO_PIN_1
#define COL3_PIN    GPIO_PIN_2
#define COL4_PIN    GPIO_PIN_3

#define LED_PORT_CLK_ENABLE   __HAL_RCC_GPIOA_CLK_ENABLE
#define ROWS_PORT_CLK_ENABLE  __HAL_RCC_GPIOB_CLK_ENABLE
#define COLS_PORT_CLK_ENABLE  __HAL_RCC_GPIOD_CLK_ENABLE

// Keypad Dimension
const uint8_t ROWS = ROWS_PINS; // Realy I need this? :))
const uint8_t COLS = COLS_PINS; // Realy I need this? :))
const uint8_t KeyPushedErrorTicksCount = 3; // contact error ticks counter (must be 2 .. 255)
const uint8_t KeypadScanPeriod = 10; // Period of Keypad Scaning (in miliseconds)

// Scan (char) codes array
const char ScanKeys[ROWS_PINS][COLS_PINS] = {
  { '1', '2', '3' },
  { '4', '5', '6' },
  { '7', '8', '9' },
  { '*', '0', '#' }
};

// Идентификатор отображаемого пункта меню.
enum{
  Measure,    // меню измерений
  Settings,   // меню настроек
  LogView,    // меню просмотра журнала
} MenuItem = Measure;

UART_HandleTypeDef huart2; //UART handler

volatile uint8_t counterCOLS  = 0;
volatile uint8_t PinSCode     = 0;    // Pin Pad Scan Code
// Cycles counter for each key
volatile uint8_t CountKeys[ROWS_PINS][COLS_PINS] = {{0, 0, 0},{0, 0, 0},{0, 0, 0},{0, 0, 0}};

void SystemClock_Config(void);
static void MX_USART2_UART_Init(void);
// Prototypes
void MenuItemSwitch(void);

void DeCodePushedRow (uint8_t PushedRow, uint8_t Col){
  if (CountKeys[PushedRow][Col] < KeyPushedErrorTicksCount){
    // We desided that this key is pushed enough
//    printf("Pushed Pin on Col:%u, Row:%u, Value:%c\n", Col, PushedRow, ScanKeys[PushedRow][Col]);
    CountKeys[PushedRow][Col]++;
  };
}

void DeCodeReleasedRow (uint8_t ReleasedRow, uint8_t Col){
  if (CountKeys[ReleasedRow][Col] >= KeyPushedErrorTicksCount){
    printf("Pushed '%c' (Col:%u, Row:%u)\n", ScanKeys[ReleasedRow][Col], Col+1, ReleasedRow+1);
  };
  CountKeys[ReleasedRow][Col]=0;
}

void ReadRows (uint8_t ColIndex){

  // Read ALL Rows and check for pushed or relased condition
  if( HAL_GPIO_ReadPin(ROWS_PORT, ROW_A_PIN) == GPIO_PIN_SET ){
    DeCodePushedRow(0,ColIndex);
  } else DeCodeReleasedRow(0,ColIndex);
  if( HAL_GPIO_ReadPin(ROWS_PORT, ROW_B_PIN) == GPIO_PIN_SET ){
    DeCodePushedRow(1,ColIndex);
  } else DeCodeReleasedRow(1,ColIndex);
  if( HAL_GPIO_ReadPin(ROWS_PORT, ROW_C_PIN) == GPIO_PIN_SET ){
    DeCodePushedRow(2,ColIndex);
  } else DeCodeReleasedRow(2,ColIndex);
  if( HAL_GPIO_ReadPin(ROWS_PORT, ROW_D_PIN) == GPIO_PIN_SET ){
    DeCodePushedRow(3,ColIndex);
  } else DeCodeReleasedRow(3,ColIndex);
}

void TimerCallAnalogue (void){

  // GPIO_PinState  ReadedState = GPIO_PIN_RESET;
  HAL_GPIO_WritePin(COLS_PORT, COL1_PIN|COL2_PIN|COL3_PIN, GPIO_PIN_RESET); // Pins reset
  switch (counterCOLS % COLS_PINS)
  {
    case 0:
      HAL_GPIO_WritePin(COLS_PORT, COL1_PIN, GPIO_PIN_SET);
      ReadRows(0);
      break;
    case 1:
      HAL_GPIO_WritePin(COLS_PORT, COL2_PIN, GPIO_PIN_SET);
      ReadRows(1);
      break;
    case 2:
      HAL_GPIO_WritePin(COLS_PORT, COL3_PIN, GPIO_PIN_SET);
      ReadRows(2);
      break;
    default:
      printf("Wrong Counter pins! \n");
  };
  counterCOLS++;  
}

void MenuItemSwitch(void){
  printf ("Now selected ");
    switch (MenuItem){
        case Measure:
            printf ("Measurements");
            break;
        case LogView:
            printf ("View Logs");
            break;
        case Settings:
            printf ("Settings");
            break;
        default:
            printf ("NOT defined");
    }
    printf(" menu item.\n");
}

void osSystickHandler(void)
{
  if ((HAL_GetTick() % 1000) == 0)           // 1 Hz blinking:
  {
    HAL_GPIO_TogglePin(LED_PORT, LED_PIN);
  }
  if ((HAL_GetTick() % KeypadScanPeriod) == 0)
  {
    TimerCallAnalogue(); //Аналог функции вызова таймера опроса клавиатуры.
  }
}

void initGPIO()
{
  GPIO_InitTypeDef GPIO_Config;       //   LED pin
  GPIO_Config.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_Config.Pull = GPIO_NOPULL;
  GPIO_Config.Speed = GPIO_SPEED_FREQ_HIGH;
  GPIO_Config.Pin = LED_PIN;          //   LED pin

  HAL_GPIO_Init(LED_PORT, &GPIO_Config);
//  __HAL_RCC_GPIOA_CLK_ENABLE(); //
  LED_PORT_CLK_ENABLE();

  GPIO_Config.Pin = COL1_PIN|COL2_PIN|COL3_PIN|COL4_PIN;        //   Columns pins
  HAL_GPIO_Init(COLS_PORT, &GPIO_Config);
  COLS_PORT_CLK_ENABLE();           //   Columns PORT Clock enable 

  GPIO_Config.Mode = GPIO_MODE_INPUT;
  GPIO_Config.Pull = GPIO_PULLDOWN;
  GPIO_Config.Pin = ROW_A_PIN|ROW_B_PIN|ROW_C_PIN|ROW_D_PIN;        //   Rows pins
  HAL_GPIO_Init(ROWS_PORT, &GPIO_Config);
  ROWS_PORT_CLK_ENABLE();           //   Rows PORT Clock enable 
}

void KeyPad_Init(void){
  uint8_t i,j;
  //                                   Array must be zero inited
  for ( i=0 ; i++ ; i <= ROWS ){
    for ( j=0 ; j++ ; j <= ROWS ){
      CountKeys[i][j]=0; 
    }
  }
  MenuItemSwitch();
}

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

  initGPIO();
  MX_USART2_UART_Init();
  KeyPad_Init();

  printf("Hello, %s!\n", "Wokwi");

  HAL_GPIO_TogglePin(LED_PORT, LED_PIN);
  //HAL_GPIO_TogglePin(COLS_PORT, COL1_PIN);
  
  while (1);

  return 0;
}

//  @brief System Clock Configuration
//  @retval None

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

  /** Initializes the RCC Oscillators according to the specified parameters
    in the RCC_OscInitTypeDef structure.
  */
  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();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  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();
  }
}

//  @brief USART2 Initialization Function
//  @param None
//  @retval None

static void MX_USART2_UART_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  __HAL_RCC_GPIOA_CLK_ENABLE();
  // PA2     ------> USART2_TX
  // PA3     ------> USART2_RX
  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;
  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();
  }
}

void Error_Handler(void)
{
  /* User can add his own implementation to report the HAL error return state */
}

// The following makes printf() write to USART2:

#define STDOUT_FILENO   1
#define STDERR_FILENO   2

int _write(int file, uint8_t *ptr, int len)
{
  switch (file)
  {
    case STDOUT_FILENO:
      HAL_UART_Transmit(&huart2, ptr, len, HAL_MAX_DELAY);
      break;

    case STDERR_FILENO:
      HAL_UART_Transmit(&huart2, ptr, len, HAL_MAX_DELAY);
      break;

    default:
      return -1;
  }

  return len;
}