// | Date 14-10-2023
// | Elevator 2 Switchs
// | By Samer Halawani [email protected]
// | ----------------------------------------


#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include<LiquidCrystal.h>


// Liquid Crystal_I2C Setup
// MEGA (21 SCL) (20 SDA)
    LiquidCrystal_I2C lcd(0x3F, 20, 4);

// First Floor & Second Floor Button / Status
    const int FL1_BTN = A0; int FL1_BTN_ButtonState = 0; int FL1_BTN_lastButtonState = 0;
    const int FL2_BTN = 13; int FL2_BTN_ButtonState = 0; int FL2_BTN_lastButtonState = 0;

// Up & Downt Button Relays
    const int Relay_UP = 4; const int Relay_Down = 5;

// Switch 1 + 2 / Status
    const int SW1 = 6; int SW1_State = 0;
    const int SW2 = 7; int SW2_State = 0;
    const int SW3 = 8; int SW3_State = 0;

// Led & buzzer Setup
    const int Led1 = A1; int led1_State = LOW;
    const int buzzer  = A2; //buzzer to arduino pin 9

// Reset Position Button X - Y
    const int RstP_BTN  = A3; int RstP_BTN_State = 0; int RstP_BTN_lastButtonState = 0;

    const long SW1_TimeOut = 500;
    const long SW2_TimeOut = 1000;
    int time1 = 0;

// constants won't change: LED & BUZZ
    unsigned long previousMillis = 0;         // will store last time LED was updated
    const long interval = 400;              // interval at which to blink (milliseconds)


void setup() {
    Serial.begin(115200);
    lcd.init();
    lcd.backlight();
    //lcd.noBacklight();

// Buttons
    pinMode(FL1_BTN, INPUT);
    pinMode(FL2_BTN, INPUT);
    pinMode(RstP_BTN, INPUT);
// Relays
    pinMode(Relay_UP, OUTPUT); pinMode(Relay_Down, OUTPUT);
// Switchs
    pinMode(SW1, INPUT); pinMode(SW2, INPUT); pinMode(SW3, INPUT);
// LED & Buzzer
    pinMode(Led1, OUTPUT); pinMode(buzzer, OUTPUT); // Set buzzer - pin 9 as an output

    Start();
}

void Start() {

    time1 = 0;
    SW1_State = digitalRead(SW1);
    SW2_State = digitalRead(SW2);

// LCD INTERFACE العرض على الشاشة 

// First Floor (1)
    if ((SW1_State == HIGH) and (SW2_State == LOW)){

      Serial.println(" Elevator Position (SW1)");
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.write(126);
      lcd.print("(XEROTK)");
      lcd.setCursor(0,1);
      lcd.print("FLOOR (1)");

    }

// Second Floor (2)
    else if ((SW2_State == HIGH) and (SW1_State == LOW)){

      Serial.println(" Elevator Position (SW2)");
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.write(126);
      lcd.print("(XEROTK)");
      lcd.setCursor(0,1);
      lcd.print("FLOOR (2)");

    }

    else {

      digitalWrite(Relay_UP,LOW);
      digitalWrite(Relay_Down,LOW);
      digitalWrite(Led1, HIGH);

      Serial.println(" ERROR!! Elevator Position error.");
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.write(126);
      lcd.print(" Switch Error!! ");
      lcd.write(127);
      lcd.setCursor(0,1);
      lcd.print(" Check Position");
      digitalWrite(Led1, HIGH);

    }
}

void loop() {


    FL1_BTN_ButtonState = digitalRead(FL1_BTN);
    SW1_State = digitalRead(SW1);

    FL2_BTN_ButtonState = digitalRead(FL2_BTN);
    SW2_State = digitalRead(SW2);

    RstP_BTN_State = digitalRead(RstP_BTN);

// == Elevator Start going UP level !
    if ((SW1_State == HIGH) and (SW2_State == LOW)){
                                        
      digitalWrite(Relay_Down,LOW);

      if ((FL2_BTN_ButtonState != FL2_BTN_lastButtonState) and (SW2_State != HIGH)) {

// If FL2_BTN Pushed
        if (FL2_BTN_ButtonState == HIGH){
          GoUP();
        }
          delay(10);
      }
        FL2_BTN_lastButtonState = FL2_BTN_ButtonState; 
    }
  
// ## END Elevator Start going UP level
// == Elevator Start going DOWN level !

    else if ((SW2_State == HIGH) and (SW1_State == LOW)){

      //delay(180);                           // توقيت الوقوق غتد السطح المستوي                                          
      digitalWrite(Relay_UP,LOW);            // ايقاف المحرك عند الوصول الى الاسفل                   
  
      if ((FL1_BTN_ButtonState != FL1_BTN_lastButtonState) and (SW1 != HIGH)) {

        //Serial.println(" Start Moving From FLOOR (2)");

// If FL1_BTN Pushed
        if (FL1_BTN_ButtonState == HIGH){
          GoDown();
        }
          delay(10);
      }
      FL1_BTN_lastButtonState == FL1_BTN_ButtonState;
    }

// ## END Elevator Start going DOWN level
// == RST Button Pushed !

    else {

      if (RstP_BTN_State == HIGH){
        Serial.println(" RST Button Pushed");
        Serial.println(" Searching Position");
        GoDown();
      }
          delay(10);
      }
        RstP_BTN_lastButtonState == RstP_BTN_State; 
}


// Go Up Section
void GoUP() {

      digitalWrite(Relay_UP,HIGH);

      Serial.println(" GoUP() Elevator Going Up SW1 ...");
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.print("Elevator going up ...");
      lcd.setCursor(15,1);
      lcd.write(126);

    while (SW2_State == LOW){

      unsigned long currentMillis = millis();
        if (currentMillis - previousMillis >= interval) {
            previousMillis = currentMillis;
            if (led1_State == LOW) {
                led1_State = HIGH;
                tone(buzzer, 1000);
            } 
            else {
                led1_State = LOW;
                noTone(buzzer);
              }
          digitalWrite(Led1, led1_State);
        }


      SW2_State = digitalRead(SW2);
         if(SW2_State == LOW){

              time1++;

            if (time1 >= SW2_TimeOut){

              Serial.print(" SW2 Time Out:");
              Serial.print(time1/100);
              Serial.println("sec");
              noTone(buzzer);
              delay(10);
              time1 = 0;
              Start();
              break;

              }

              delay(10);
           } else {

              digitalWrite(Led1, LOW);
              noTone(buzzer);
              delay(15);
              time1 = 0;

              Start();

           }
        }

    }
  


// Go Down Section
void GoDown() {

    digitalWrite(Relay_Down,HIGH);

          Serial.println(" GoDown() Elevator Going Down SW2 ...");
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print(" Elevator Going Down ...");
          lcd.setCursor(15,1);
          lcd.write(127);

      while (SW1_State == LOW){
    
        unsigned long currentMillis = millis();
        if (currentMillis - previousMillis >= interval) {
          previousMillis = currentMillis;
          if (led1_State == LOW) {
            led1_State = HIGH;
            tone(buzzer, 2000);
          } else {
              led1_State = LOW;
              noTone(buzzer);
            }

        digitalWrite(Led1, led1_State);
        }

      SW1_State = digitalRead(SW1);

         if(SW1_State == LOW){

              time1++;

            if (time1 >= SW1_TimeOut){

              Serial.print(" SW1 Time Out:");
              Serial.print(time1/100);
              Serial.println("sec");
              noTone(buzzer);
              delay(10);
              time1 = 0;
              Start();
              break;

              }

              delay(10);
           } else {

              digitalWrite(Led1, LOW);
              noTone(buzzer);
              delay(10);

              time1 = 0;
              Start();

           }






    }

 }