#include <EEPROM.h>

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


LiquidCrystal_I2C lcd(0x27, 16, 2); // initialize pins


long duration, inches;
int set_val,percentage;
bool state,pump;


void setup() {
  
  lcd.begin(16, 2); // initialize lcd screen, set screen dimensions
  lcd.print("WATER LEVEL:"); // print water level
  lcd.setCursor(0, 1); // get to next line
  lcd.print("PUMP:OFF MANUAL"); // initialize to manual
  
  pinMode(2, OUTPUT); //set pin to give output
  pinMode(3, INPUT); // set pin to give input
  pinMode(10, INPUT_PULLUP); //set pin to default high
  pinMode(11, INPUT_PULLUP); //set pin to default high
  pinMode(13, OUTPUT); // set pin to output
  
   set_val=EEPROM.read(0); // set 
   if(set_val>150)set_val=150;
}
void loop() {
  
   digitalWrite(2, HIGH); //set pin 2 to high
   delayMicroseconds(10); // produce delay
   digitalWrite(2, LOW); // set pin 2 to low
   duration = pulseIn(3, HIGH);// measures time of pin going from high to low
   inches = microsecondsToInches(duration); //based on the time taken for pin to go from high to low, converts to distance
   
   percentage=(set_val-inches)*100/set_val;// sets percentage value based on distance of water surface
   
   lcd.setCursor(12, 0); // shifts cursor to 12th place
   if(percentage<0)percentage=0; //if else statement
   lcd.print(percentage);
   lcd.print("%   ");
    
   if(percentage<30&digitalRead(11))pump=1; // if percentage is less than 30%, turn on pump
   if(percentage>95)pump=0; // if percentage greater than 95%, turn off pump
   digitalWrite(13,!pump); //turn on relay led
     
   lcd.setCursor(5, 1); // shift cursor to position
   if(pump==1)lcd.print("ON ");// if pump is on, show "on" on screen
   else if(pump==0) lcd.print("OFF");// if pump is off, show "off" on screen
   
   lcd.setCursor(9, 1); // shift cursor to point
   if(!digitalRead(11))lcd.print("MANUAL"); // if slide switch is on manual, print "manual"
   else lcd.print("AUTO   "); //else print "auto"
    
    if(!digitalRead(10)&!state&digitalRead(11)){
      state=1;
      set_val=inches;
      EEPROM.write(0, set_val);
      }
      
     if(!digitalRead(10)&!state&!digitalRead(11)){
        state=1;
        pump=!pump;
     
      }
      
    if(digitalRead(10))state=0;
      
    
    delay(500);
}
long microsecondsToInches(long microseconds) {
   return microseconds / 74 / 2;
}