// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
// Uses my Bit Bang I2C library. You can find it here:
// https://github.com/bitbank2/BitBang_I2C
#include <BitBang_I2C.h>
#include <RTClib.h>
#include <LiquidCrystal.h>
#include <LiquidCrystal_I2C.h>


char daysOfTheWeek[7][12] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
String daysW[7] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};

LiquidCrystal lcd( 12, 11, 5, 4, 3, 2 );
LiquidCrystal_I2C lcd2(0x27, 16, 2); // I2C address 0x27, 16 column and 2 rows

BBI2C bbi2c;
uint8_t rtc_adr = 0x68; // RTC address
uint8_t bcd2bin(uint8_t);
uint8_t bin2bcd(uint8_t);
void printDec( int, byte );

DateTime read_now(int);
uint8_t isRunning(void);
void adjust(const DateTime &dt);

void setup() {
  Serial.begin(115200);
  memset(&bbi2c, 0, sizeof(bbi2c));
  lcd.begin( 16, 2 );
  lcd.clear();


  lcd2.init();
  lcd2.backlight();
  lcd2.clear(); 

  // BBI2C bbi2c;
  bbi2c.bWire =0; // use bit banging
  bbi2c.iSDA = 8; // SDA on GPIO pin 8
  bbi2c.iSCL = 9; // SCL on GPIO pin 9
  I2CInit(&bbi2c, 100000L);
  lcd.print( "Setting Time" );
  delay(100); // allow devices to power up
  adjust(DateTime(2023, 8, 14, 11, 12, 10));
  delay(1000); // allow devices to power up
}
int loop_counter = 0;

void loop() {
  // DateTime now;

  loop_counter++;
  Serial.println("Starting I2C Test");
  lcd.clear();
  lcd2.clear(); 
  lcd2.print("loop_count:");
  lcd2.print(loop_counter);
  if(I2CTest(&bbi2c, rtc_adr))
  {
    Serial.println("RTC found");
    if(!isRunning())
    {
      Serial.println("RTC is NOT running");
    }
    else
    {
      Serial.println("RTC is running");
    }
    DateTime now = read_now(0);
    Serial.print(now.year(), DEC);
    Serial.print('/');
    Serial.print(now.month(), DEC);
    Serial.print('/');
    Serial.print(now.day(), DEC);
    Serial.print(" (");
    Serial.print(daysOfTheWeek[now.dayOfTheWeek()]);
    Serial.print(") ");
    Serial.print(now.hour(), DEC);
    Serial.print(':');
    Serial.print(now.minute(), DEC);
    Serial.print(':');
    Serial.print(now.second(), DEC);
    Serial.println();

	  lcd.setCursor(2, 0);
	  lcd.print( daysW[now.dayOfTheWeek()] );
	  lcd.print( " " );
	  printDec( now.day(), 0 );
	  printDec( now.month(), 1 );
	  printDec( now.year()-2000, 1 );
	
	  lcd.setCursor( 4, 1 );
	  printDec( now.hour(), 0 );
	  printDec( now.minute(), 2 );
	  printDec( now.second(), 2 );
  }
  else
  {
    Serial.println("RTC not found");
  }
  delay(1000);
}


uint8_t bcd2bin(uint8_t val) { return val - 6 * (val >> 4); }
uint8_t bin2bcd(uint8_t val) { return val + 6 * (val / 10); }

/**************************************************************************/
/*!
    @brief  Getting current time from RTC
    @return DateTime with time details
*/
/**************************************************************************/
DateTime read_now(int a){
  uint8_t buffer[7];
  buffer[0] = 0;
  // i2c_dev->write_then_read(buffer, 1, buffer, 7);
  I2CReadRegister(&bbi2c, rtc_adr, 0, buffer, 7);

  return DateTime(bcd2bin(buffer[6]) + 2000U, bcd2bin(buffer[5]),
                  bcd2bin(buffer[4]), bcd2bin(buffer[2]), bcd2bin(buffer[1]),
                  bcd2bin(buffer[0] & 0x7F));
}

/**************************************************************************/
/*!
    @brief  Is the DS1307 running? Check the Clock Halt bit in register 0
    @return 1 if the RTC is running, 0 if not
*/
/**************************************************************************/
uint8_t isRunning(void) {
  uint8_t buffer[1];
  buffer[0] = 0;
  I2CReadRegister(&bbi2c, rtc_adr, 0, buffer, 1) >> 7;
  return !(buffer[0] >> 7);
}

void adjust(const DateTime &dt) {
  uint8_t buffer[8] = {0,
                       bin2bcd(dt.second()),
                       bin2bcd(dt.minute()),
                       bin2bcd(dt.hour()),
                       0,
                       bin2bcd(dt.day()),
                       bin2bcd(dt.month()),
                       bin2bcd(dt.year() - 2000U)};
  // i2c_dev->write(buffer, 8);
  I2CWrite(&bbi2c, rtc_adr, buffer, 8);
}

void printDec( int dec, byte pre )
{
  if     ( pre == 1 ) lcd.print( "/" );
  else if( pre == 2 ) lcd.print( ":" );

  if( dec < 10 ) lcd.print("0");
  lcd.print( dec, DEC );
}