#include <stdio.h>
#include "pico/stdlib.h"
#include "pico/cyw43_arch.h"
#include "hardware/i2c.h"

#define I2C_INTERFACE i2c0 //utilizaemos o i2c0
#define ds1307_SDA 4            
#define ds1307_SCL 5            
#define ds1307_I2C_ADDR 0x68 

void init();
//conversores
uint8_t BCD(uint8_t val);
uint8_t BCD_return(uint8_t val);
void rtc_config(uint8_t sec, uint8_t min, uint8_t hour, uint8_t day_of_week, uint8_t day, uint8_t month, uint8_t year);
void rtc_data(uint8_t *sec, uint8_t *min, uint8_t *hour, uint8_t *day_of_week, uint8_t *day, uint8_t *month, uint8_t *year);

int main() {
  stdio_init_all();
  init();
  rtc_config(0, 27, 13, 2, 24, 9, 24);
  uint8_t sec, min, hour, day_of_week, day, month, year; 

  while (true) {
  
  rtc_data(&sec, &min, &hour, &day_of_week, &day, &month, &year); 
 
  printf("Agora sao: %02d-%02d-20%02d [%02d:%02d:%02d]\n", day, month, year, hour, min, sec); 
 
  sleep_ms(5000); // Aguardar 5 segundos 
    
  }
}

void init() { 
    i2c_init(I2C_INTERFACE, 100000);  
    gpio_set_function(ds1307_SDA, GPIO_FUNC_I2C); 
    gpio_set_function(ds1307_SCL, GPIO_FUNC_I2C); 
    gpio_pull_up(ds1307_SDA); 
    gpio_pull_up(ds1307_SCL); 
} 

uint8_t BCD(uint8_t val) { 
    return ((val / 10) << 4) | (val % 10); 
} 
 
uint8_t BCD_return(uint8_t val) { 
    return ((val >> 4) * 10) + (val & 0x0F); 
} 

void rtc_config(uint8_t sec, uint8_t min, uint8_t hour, uint8_t day_of_week, uint8_t day, uint8_t month, uint8_t year) { 
    uint8_t datetime_data[7] = { 
        BCD(sec), 
        BCD(min), 
        BCD(hour), 
        BCD(day_of_week), 
        BCD(day), 
        BCD(month), 
        BCD(year) 
    }; 

    //comeca daqui
    uint8_t data_to_write[8] = {0x00};

    for (int i = 0; i < 7; i++) { 
      data_to_write[i + 1] = datetime_data[i]; 
    } 
  

    i2c_write_blocking(I2C_INTERFACE, ds1307_I2C_ADDR, data_to_write, 8, false); 
} 

void rtc_data(uint8_t *sec, uint8_t *min, uint8_t *hour, uint8_t *day_of_week, uint8_t *day, uint8_t *month, uint8_t *year) { 
    uint8_t start = 0x00; 
    uint8_t datetime_data[7]; 
 
  //habilita e busca os dados
    i2c_write_blocking(I2C_INTERFACE, ds1307_I2C_ADDR, &start, 1, true); 
    i2c_read_blocking(I2C_INTERFACE, ds1307_I2C_ADDR, datetime_data, 7, false); 
  
    *sec = BCD_return(datetime_data[0]); 
    *min = BCD_return(datetime_data[1]); 
    *hour = BCD_return(datetime_data[2]); 
    *day_of_week = BCD_return(datetime_data[3]); 
    *day = BCD_return(datetime_data[4]); 
    *month = BCD_return(datetime_data[5]); 
    *year = BCD_return(datetime_data[6]); 
}