#include <HX711.h>
#include <ESP32Servo.h>

#define SERVO_PIN 14 // ESP32 pin GPIO26 connected to servo motor


// HX711 circuit wiring
const int LOADCELL_DOUT_PIN = 5;
const int LOADCELL_SCK_PIN = 4;

const int LED_PIN = 2;

const int buttonPin = 0; 

int lastButtonState;    // the previous state of button
int currentButtonState; // the current state of button

float reading=0;
int lock=0;

int cs=0;

HX711 scale;

Servo servoMotor;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(LED_PIN, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);   // set ESP32 pin to input pull-up mode

  servoMotor.attach(SERVO_PIN, 500, 2400);
  
  delay(1000);
  servoMotor.write(0);
  delay(1000);

  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
 
}



void loop() 
{
//+++++++++++++++++
//******

  cs=0;
  Serial.println("IV DRIP AUTOMATION");
  digitalWrite(LED_PIN, HIGH);
  Serial.println("Tare... remove any weights from the scale. Then press the button");

  while(cs==0)
  {
  currentButtonState = digitalRead(buttonPin);
  lastButtonState    = currentButtonState;      // save the last state
  delay(100);
  currentButtonState = digitalRead(buttonPin); // read new state
 //Serial.println(currentButtonState);
  if(lastButtonState == HIGH && currentButtonState == LOW) 
  {
    Serial.println("cs1");
    cs=1;
  }
  
  }
//******

  
  digitalWrite(LED_PIN, LOW);
  
  if (scale.is_ready()) 
  {
    // first time set scale balank  i.e scale.set_scale() 
    // Then get the reading for a known weight
    // calibration factor = reading / known weight
    // scale.set_scale(INSERT YOUR CALIBRATION FACTOR);
    scale.set_scale(420);    
    
    delay(1000);
    scale.tare();
    Serial.println("Tare done...");
    digitalWrite(LED_PIN, HIGH);

    servoMotor.write(90);
    delay(2000);

    Serial.println("HANG THE IV BOTTLE. THEN PRESS THE BUTTON");

   cs=1;
  while(cs==1)
  {
  currentButtonState = digitalRead(buttonPin);
  lastButtonState    = currentButtonState;      // save the last state
  delay(100);
  currentButtonState = digitalRead(buttonPin); // read new state
 //Serial.println(currentButtonState);
  if(lastButtonState == HIGH && currentButtonState == LOW) 
  {
    cs=2;
    Serial.println("cs2");
    digitalWrite(LED_PIN, LOW);

  }
  
  }

    //Serial.print("Place a known weight on the scale...");
    //delay(5000);
    //reading = scale.get_units(10);
    //Serial.print("Result: ");
    //Serial.println(reading);
  } 
  else {
    Serial.println("HX711 not found.");
    cs=100;
    while(true)
    {
    digitalWrite(LED_PIN, HIGH);
    delay(2000);
    digitalWrite(LED_PIN, LOW);
    delay(1000);
    }
  }





//+++++++++++++++++
lock=0;
while(cs==2)
{
 Serial.print("reading...");
 delay(3000);
    reading = scale.get_units(10);
    Serial.print("Result: ");
    Serial.println(reading);

    if (reading<=0.20 && lock==0)
    {
      lock=1;
       servoMotor.write(180);
       delay(1000);
       cs=3;
       Serial.println("IV drip locked");
    }
  delay(1000);
}


currentButtonState = digitalRead(buttonPin);
while(cs==3 && currentButtonState == HIGH )
{
  digitalWrite(LED_PIN, HIGH);
    delay(500);
    digitalWrite(LED_PIN, LOW);
    delay(500);
    currentButtonState = digitalRead(buttonPin);
}

    servoMotor.write(0);
    delay(2000);
    digitalWrite(LED_PIN, HIGH);
    


}