// Basic RTC clock using Attiny85
//  press blue to enter, shift or leave setting mode, 
//  press green to increase hours or minutes

//TODO: Make settings more responsive

#include <ButtonGestures.h>
#include <Wire.h>
#include <TM1637TinyDisplay.h>

// DS1307 related
#define DS1307_ADDR 0x68
byte seconds,minutes,hours;

// Instantiate TM1637TinyDisplay Class
TM1637TinyDisplay display(3, 4); //PB3, PB4
//TM1637 has no address and is not using I2C

ButtonGestures buttonState(PB1, LOW, INPUT_PULLUP); //blue
ButtonGestures buttonSet(PB5, LOW, INPUT_PULLUP); //green

//state: 0 (normal), 1=set hours, 2=set minutes
byte state = 0;
const byte dms = 100;
const byte blk[2] = {0,0};
bool upd = false; 

void setup() {
  display.begin();
  Wire.begin();
  delay(100);
}

void loop() {

upd = false;
uint8_t s = buttonSet.check_button();
if (s==SINGLE_PRESS_SHORT) {
  if (state==1) {
    hours = (hours==23) ? 0 : hours + 1;
    setTime();
    upd = true;
  } else if (state==2) {
    minutes = (minutes==59) ? 0 : minutes + 1;
    setTime();
    upd = true;
  }
}
s = buttonState.check_button();
if (s==SINGLE_PRESS_SHORT) {
  state = (state==2) ? 0 : state + 1;
}

switch (state) {
case 0:
  display.showNumberDec(hours, 0b01000000, false, 2, 0);
  display.showNumberDec(minutes, 0, true, 2, 2);
  break;
case 1: //hours blinking
  display.showNumberDec(minutes, 0, true, 2, 2);
  if(upd || millis() & 512) {
    display.showNumberDec(hours, 0b01000000, false, 2, 0);      
  } else {
    display.setSegments(blk,2,0);
  }
  break;
case 2: //minutes blinking
  display.showNumberDec(hours,0b01000000, false, 2, 0); 
  if(upd || millis() & 512) {
    display.showNumberDec(minutes, 0, true, 2, 2);
  } else {
    display.setSegments(blk,2,2);
  }
  break;
}
delay(dms);

//reload time from RTC
getTime();

}

void getTime(){
  byte wireRet = 0;
  
  Wire.beginTransmission(DS1307_ADDR); // reset DS1307 register pointer 
  Wire.write(0); 
  wireRet = Wire.endTransmission(); 
  if (wireRet) delay(1500);
  wireRet = Wire.requestFrom(DS1307_ADDR, 3);    // request n bytes from DS1307
  if (wireRet) delay(1500);

  seconds = bcdToDec(Wire.read());  //read bytes received
  minutes = bcdToDec(Wire.read());      
  hours = bcdToDec(Wire.read());        
}

byte bcdToDec(byte val) {               // Convert binary coded decimal to normal decimal numbers
  return (val>>4) * 10 + (val & 15);
  //Each set of 4 bits represents a digit
}
byte decToBcd(byte val) {               // Convert to BCD
  return (int)(val/10)*16 + val - 10*(int)(val/10);
}

void setTime() {
  byte wireRet = 0;
  Wire.beginTransmission(DS1307_ADDR);
  Wire.write(0); // reset register pointer  
  Wire.write(decToBcd(seconds)); // write the seconds, with the stop bit clear to restart
  Wire.write(decToBcd(minutes));
  Wire.write(decToBcd(hours));
  wireRet = Wire.endTransmission(); 
  return wireRet;
}