/**
 * Complete project details at https://RandomNerdTutorials.com/arduino-load-cell-hx711/
 *
 * HX711 library for Arduino - example file
 * https://github.com/bogde/HX711
 *
 * MIT License
 * (c) 2018 Bogdan Necula
 *

  ANGLE => 90 => OPEN
        => 180 => CLOSE

**/

#include <Arduino.h> 
#include "HX711.h"
#include <Servo.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 20, 4);


Servo ServoValve; // Create a servo object to open & close the valve
Servo ServoCover; // servo to put a cover under the spout

// HX711 circuit wiring
const int LOADCELL_DOUT_PIN = 2;
const int LOADCELL_SCK_PIN = 3;

// SERVO'S
const int ServoValvePIN = 9;
const int ServoCoverPIN = 7;

boolean life_weight = false;
boolean moving_window = false;

String received_info = "";
String commandStr = "";

int avg_readings = 1;

HX711 scale;

long longArray[30] ;
int array_pointer = 0 ;

int test = 0;

// variables to calc slope & intercept
double intercept = 0;
double slope = 0;
long X1 = 0;  //SIGNAL'
long X2 = 0;  //SIGNAL
int Y1 = 1000;  //WEIGHT
int Y2 = 4000;  //WEIGHT
int  slope_and_intercept_calculated = 0;
long read_signal = 0;
int read_weight = 0;

int dosing_weight = 0;
int start_weight = 0;
int end_weight = 0;

int dosing_active = 0;

// tzé formula
//  slope = (Y2-Y1) / (X2-X1)
//  intercept = X1 - (slope * Y1)
//  

// Function to calculate the average of elements in a float array
float calculateAverage(long arr[]) {
    float sum = 0;

    // Calculate the sum of all elements in the array
    for (int i = 0; i < 30; i++) {
        sum += arr[i];
    }

    // Calculate the average
    float average = sum / 30;

    return average;
}



void setup() {

  Serial.begin(115200);
  Serial.println("ready to get some commands my master");
  //Serial.println("Initializing the scale");

  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);

            
  //scale.set_scale(-459.542);
  scale.set_scale(471.497);                      // this value is obtained by calibrating the scale with known weights; see the README for details
  scale.tare();               // reset the scale to 0

  ServoCover.attach(ServoCoverPIN); // Attach the servo 
  ServoValve.attach(ServoValvePIN); // Attach the servo 

  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(1, 0);
  lcd.print("READY TO BE");
  lcd.setCursor(1, 1);
  lcd.print("CALIBRATED");
  delay(500);


  for (int angle = 0; angle <= 180; angle++) {
    ServoCover.write(angle); // Set the servo position
    ServoValve.write(angle); // Set the servo position
    delay(20); // Wait for servo to reach the position

  }

  ServoCover.detach();
  ServoValve.detach();

}

void loop() {
  // Serial.print("one reading:\t");
  // Serial.print(scale.get_units(), 1);
  //Serial.print("\t| average:\t");
  //Serial.println(scale.get_units(10), 5);

  // delay(5000);
  //Serial.println(scale.read());


  if (Serial.available()) {
      char receivedChar = Serial.read();

      Serial.print(receivedChar);

      if (receivedChar == '\r') {
          // Process the command when EOL is received
          int the_number = commandStr.substring(3).toInt();
          commandStr = commandStr.substring(0, 3);
   

          if (commandStr == "PRL"){
              if (the_number == 1) {
            // print live = true
              life_weight = true;
              lcd.clear();
              lcd.setCursor(1, 0);
              //lcd.print("Life DATA !");
              test = 0;
  
            }
            else{
              life_weight = false;
              lcd.clear();
              lcd.setCursor(0, 0);
              lcd.print("NO Life DATA :-(");

            }
          }


          if (commandStr == "MOW"){
              if (the_number == 1) {
            // print live = true
              moving_window = true;
              Serial.println("monving_window = true");
            }
            else{
              moving_window = false;
              Serial.println("monving_window = false");
            }
          }

          if (commandStr == "LON"){
              lcd.backlight();
           } 

          if (commandStr == "LOF"){
              lcd.noBacklight();
           } 

          if (commandStr == "SY1"){
              Y1 = the_number;
              lcd.clear();
              lcd.setCursor(0, 0);
              lcd.print("Y1 = ");
              lcd.setCursor(6, 0);
              lcd.print(Y1);
           } 

          if (commandStr == "SY2"){
              Y2 = the_number;
              lcd.clear();
              lcd.setCursor(0, 0);
              lcd.print("Y2 = ");
              lcd.setCursor(6, 0);
              lcd.print(Y2);

           } 

          if (commandStr == "AVG"){
            // alter angle valve servo
            avg_readings = the_number;
            lcd.clear();
            lcd.setCursor(0, 0);
            lcd.print("New AVG = ");
            lcd.setCursor(10, 0);
            lcd.print(avg_readings);
            delay(2000);
          }

          if (commandStr == "AAA"){
            // alter angle valve servo
            ServoValve.attach(ServoValvePIN); // Attach the servo 
            
            ServoValve.write(the_number);
            
            delay(1000);

            ServoCover.detach();
            ServoValve.detach();

          }

          if (commandStr == "RES"){
            // RESET
            intercept = 0;
            slope = 0;
            slope_and_intercept_calculated = 0;
            Serial.println("reset done");
          }

          if (commandStr == "BBB"){
            // alter angle valve servo
            ServoCover.attach(ServoCoverPIN); // Attach the servo 
            
            ServoCover.write(the_number);

            delay(1000);

            ServoCover.detach();
          }
            // Convert the following 6 characters to an integer
          

          if (commandStr == "CAL"){
            // CALIBRATE LOW
            lcd.clear();
            lcd.setCursor(1, 0);
            lcd.print("CAL LOW WEIGHT");
            X1 = scale.read_average(100);
            lcd.setCursor(1, 1);
            lcd.print(X1);
            
          }

          if (commandStr == "CAH"){
            // CALIBRATE LOW
            lcd.clear();
            lcd.setCursor(1, 0);
            lcd.print("CAL HIGH WEIGHT");
            X2 = scale.read_average(100);
            lcd.setCursor(1, 1);
            lcd.print(X2);
            
          }

          if (commandStr == "DOS"){
            // DOSING
            lcd.clear();
            lcd.setCursor(1, 0);
            lcd.print("DOSING");
            
            dosing_weight = the_number;

            lcd.setCursor(0, 1);
            lcd.print(dosing_weight);

            lcd.setCursor(4, 1);
            lcd.print(" gram ");


            read_signal = scale.read_average(100);
            
            start_weight = intercept + slope * read_signal;
            end_weight = start_weight - dosing_weight;

            ServoCover.attach(ServoCoverPIN); // Attach the servo 
            ServoValve.attach(ServoValvePIN); // Attach the servo

            ServoCover.write(90); // Set the servo position
            delay(2000); // make sure to wait until cover is full open
            ServoValve.write(90); // Set the servo position

            dosing_active = 1;


          }

          if (commandStr == "INF"){
            Serial.print("X1     = ");
            Serial.println(X1);               

            Serial.print("Y1     = ");
            Serial.println(Y1);

            Serial.print("X2     = ");
            Serial.println(X2);

            Serial.print("Y2     = ");
            Serial.println(Y2);

            Serial.print("slope_and_intercept_calculated     = ");
            Serial.println(slope_and_intercept_calculated); 

          }


          delay(10);

          Serial.print("received command :");
          Serial.print(commandStr);
          Serial.print("      received number :");
          Serial.println(the_number);

          commandStr = "";
        }
      else{
        commandStr += receivedChar;
      }

  }



if ((X1 != 0) && (X2 != 0) && (slope_and_intercept_calculated == 0)){
  // time to calc slope and intercept !
  Serial.println("calc slope & intercept");

  Serial.print("X1     = ");
  Serial.println(X1);

  Serial.print("Y1     = ");
  Serial.println(Y1);

  Serial.print("X2     = ");
  Serial.println(X2);

  Serial.print("Y2     = ");
  Serial.println(Y2);

  Serial.print("slope_and_intercept_calculated     = ");
  Serial.println(slope_and_intercept_calculated);


  slope = (double)(Y2-Y1) / (X2-X1);
  intercept = Y1 - (slope * X1);
  Serial.print("Slope     = ");
  Serial.println(slope);
  Serial.print("Intercept = ");
  Serial.println(intercept);
  slope_and_intercept_calculated = 1;

}

  if (life_weight == true) {
    //Serial.println(scale.get_units(1), 1); 
    //Serial.print("LW: ");
    Serial.println(scale.read_average(avg_readings));
    read_signal = scale.read_average(avg_readings);
    lcd.clear();
    lcd.setCursor(1, 0);
    lcd.print(read_signal);

    read_weight = intercept + slope * read_signal;

    lcd.setCursor(1, 1);
    lcd.print(read_weight);

    lcd.setCursor(10, 1);
    lcd.print(test);
    test++;
    if (test > 8){test=0;}
  } 

  // moving window
  longArray[array_pointer] = scale.read();

  if (array_pointer < 30){
    array_pointer++;
  }
  else{
    array_pointer = 0;
  }

  if (moving_window == true) {
    //Serial.println(scale.get_units(1), 1); 
    Serial.print("MW: ");
    Serial.println(calculateAverage(longArray));
  } 


  if (dosing_active > 0){
    // start_weight = intercept + slope * read_signal;
    end_weight = start_weight - dosing_weight;

    read_signal = scale.read_average(avg_readings);
    read_weight = intercept + slope * read_signal;
    
    lcd.setCursor(1, 5);
    lcd.print("     ");
    lcd.print(read_weight);

    if (read_weight <= end_weight){
      dosing_active = 0;
      ServoCover.write(180); // Set the servo position
      ServoValve.write(180); // Set the servo position
      
      delay(1000);

      ServoCover.detach(); 
      ServoValve.detach();
    }
    


  }

}