#include "RTClib.h"
RTC_DS1307 rtc;

#define SW1 7
#define SW2 10
#define SW3 6
#define LED1 3

bool st_SetH = 0;
bool st_SetM = 0;
bool st_SetS = 0;

byte h_set;   //  Keep hour value
byte m_set;   //  Keep  Minute  Value
byte s_set;   //  Keep  Minute  Value

void setup() {
  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    Serial.flush();
    abort();
  }
  pinMode(SW1, INPUT_PULLUP);
  pinMode(SW2, INPUT_PULLUP);
  pinMode(SW3, INPUT_PULLUP);
  pinMode(LED1, OUTPUT);
  Serial.begin(9600);
  Serial.println("START");
}

void loop() {
  DateTime now = rtc.now();
  char i[20];
  if(digitalRead(SW3) == 0) {
    delay(1000);
    if(digitalRead(SW3) == 0) {
    st_SetH = 1;   //  Set Variable  st_SetH  = 1 for enter while loop
    Serial.println("--------------------");
    Serial.println("  SET TIMER MODE");
    Serial.println("--------------------");
    Serial.println(" -> SET HOURS");
    //  --- Mode  Set Timer H ---
    while(st_SetH == 1) {
      if(digitalRead(SW1) == 0) {
        while(digitalRead(SW1) == 0) delay(1);
        h_set = h_set + 1;
        if(h_set > 24) h_set = 24;
        Serial.println("HOURS : " + String(h_set));
        delay(100);
      }   //  Add Time  Hour 1  value
      if(digitalRead(SW2) == 0) {
        while(digitalRead(SW2) == 0) delay(1);
        h_set = h_set - 1;
        if(h_set >= 250) h_set = 0;
        Serial.println("HOURS : " + String(h_set));
        delay(100);
      }   //  minus Time  Hour 1  value  
      if(digitalRead(SW3) == 0) {
        delay(1000);
        if(digitalRead(SW3) == 0) {   //  Recheck press Switch2
          st_SetH = 0;    //  Set for exit  while st_SetH
          st_SetM = 1;    //  For enter while st_SetM
          Serial.println("[SET HOURS IS OK]");
          Serial.println(" -> SET MINUTE");
        }
      } //  exit while loop
    }   //  While Set H
    //  -----------------------
    //  --- Mode  Set Timer M ---
    while(st_SetM == 1) {
      if(digitalRead(SW1) == 0) {
        while(digitalRead(SW1) == 0) delay(1);
        m_set = m_set + 2;
        if(m_set > 60) m_set = 60;
        Serial.println("MINUTE : " + String(m_set));
        delay(100);
      }   //  Add Time  Minute 1  value
      if(digitalRead(SW2) == 0) {
        while(digitalRead(SW2) == 0) delay(1);
        m_set = m_set - 2;
        if(m_set >= 250) m_set = 0;
        Serial.println("MINUTE : " + String(m_set));
        delay(100);
      }   //  minus Time  Minute 1  value  
      if(digitalRead(SW3) == 0) {
        delay(1000);
        if(digitalRead(SW3) == 0) {   //  Recheck press Switch2
          st_SetM = 0;    //  Set for exit  while st_SetM
          st_SetS = 1;    //  For enter while st_SetS
          Serial.println("[SET MINUTE IS OK]");
          Serial.println(" -> SET SECOND");
        }
    }
    //---------------------------
    }   //  exit  while loop
    //  --- Mode  Set Timer S ---
    while(st_SetS == 1) {
      if(digitalRead(SW1) == 0) {
        while(digitalRead(SW1) == 0) delay(1);
        s_set = s_set + 2;
        if(s_set > 60) s_set = 60;
        Serial.println("SECOND : " + String(s_set));
        delay(100);
      }   //  Add Time  Second 1  value
      if(digitalRead(SW2) == 0) {
        while(digitalRead(SW2) == 0) delay(1);
        s_set = s_set - 2;
        if(s_set >= 250) s_set = 0;
        Serial.println("SECOND : " + String(s_set));
        delay(100);
      }   //  Second Time  Minute 1  value  
      if(digitalRead(SW3) == 0) {
        delay(1000);
        if(digitalRead(SW3) == 0) {   //  Recheck press Switch2
          st_SetS = 0;    //  For enter while st_SetS
          Serial.println("[SET SECOND IS OK]");
        }
    }
    }   //  exit  while loop
    //---------------------------
  }     //  Recheck Press SW2
}   //  Press SW2
  if(h_set == now.hour() && m_set == now.minute() && s_set == now.second()) {
    digitalWrite(LED1, HIGH);
    Serial.println("LED ON");
  }
  else digitalWrite(LED1, LOW);
  sprintf(i, "Current Time = %02d : %02d : %02d \t",now.hour() ,now.minute(), now.second());
  Serial.print(i);
  sprintf(i, "Timer ON = %0d : %0d : %0d",h_set ,m_set, s_set);
  Serial.println(i);
  delay(1000);
};