Secret knock pattern door lock

 Arduino code:

const int knockSensor = 0;

const int programSwitch = 2;

const int lockMotor = 3;

const int redLED = 4;

const int greenLED = 5;

 

const int threshold = 3;

const int rejectValue = 25;

const int averageRejectValue = 15;

const int knockFadeTime = 150;

const int lockTurnTime = 2000;

const int maximumKnocks = 20;

const int knockComplete = 1200;

int secretCode[maximumKnocks] = {50, 25, 25, 50, 100, 50, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

int knockReadings[maximumKnocks];

int knockSensorValue = 0;

int programButtonPressed = false;

void setup() {

  pinMode(lockMotor, OUTPUT);

  pinMode(redLED, OUTPUT);

  pinMode(greenLED, OUTPUT);

  pinMode(programSwitch, INPUT);

  

  Serial.begin(9600);

  Serial.println("Program start.");

  

  digitalWrite(greenLED, HIGH);

}

void loop() {

  knockSensorValue = analogRead(knockSensor);

  

  if (digitalRead(programSwitch)==HIGH){

    programButtonPressed = true;

    digitalWrite(redLED, HIGH);

  } else {

    programButtonPressed = false;

    digitalWrite(redLED, LOW);

  }

  

  if (knockSensorValue >=threshold){

    listenToSecretKnock();

  }

} 

void listenToSecretKnock(){

  Serial.println("knock starting");   

  int i = 0;

  for (i=0;i<maximumKnocks;i++){

    knockReadings[i]=0;

  }

  

  int currentKnockNumber=0;

  int startTime=millis();

  int now=millis();

  

  digitalWrite(greenLED, LOW);

  if (programButtonPressed==true){

     digitalWrite(redLED, LOW);

  }

  delay(knockFadeTime);

  digitalWrite(greenLED, HIGH);  

  if (programButtonPressed==true){

     digitalWrite(redLED, HIGH);                        

  }

  do {

    knockSensorValue = analogRead(knockSensor);

    if (knockSensorValue >=threshold){

      Serial.println("knock.");

      now=millis();

      knockReadings[currentKnockNumber] = now-startTime;

      currentKnockNumber ++;

      startTime=now;          

      digitalWrite(greenLED, LOW);  

      if (programButtonPressed==true){

        digitalWrite(redLED, LOW);

      }

      delay(knockFadeTime);

      digitalWrite(greenLED, HIGH);

      if (programButtonPressed==true){

        digitalWrite(redLED, HIGH);                         

      }

    }

    now=millis();

    

  } while ((now-startTime < knockComplete) && (currentKnockNumber < maximumKnocks));

  

  if (programButtonPressed==false){

    if (validateKnock() == true){

      triggerDoorUnlock(); 

    } else {

      Serial.println("Secret knock failed.");

      digitalWrite(greenLED, LOW);

      for (i=0;i<4;i++){          

        digitalWrite(redLED, HIGH);

        delay(100);

        digitalWrite(redLED, LOW);

        delay(100);

      }

      digitalWrite(greenLED, HIGH);

    }

  } else {

    validateKnock();

    Serial.println("New lock stored.");

    digitalWrite(redLED, LOW);

    digitalWrite(greenLED, HIGH);

    for (i=0;i<3;i++){

      delay(100);

      digitalWrite(redLED, HIGH);

      digitalWrite(greenLED, LOW);

      delay(100);

      digitalWrite(redLED, LOW);

      digitalWrite(greenLED, HIGH);      

    }

  }

}

void triggerDoorUnlock(){

  Serial.println("Door unlocked!");

  int i=0;

  

  digitalWrite(lockMotor, HIGH);

  digitalWrite(greenLED, HIGH);

  

  delay (lockTurnTime);

  

  digitalWrite(lockMotor, LOW);

  

  for (i=0; i < 5; i++){   

      digitalWrite(greenLED, LOW);

      delay(100);

      digitalWrite(greenLED, HIGH);

      delay(100);

  }

   

}

boolean validateKnock(){

  int i=0;

 

  int currentKnockCount = 0;

  int secretKnockCount = 0;

  int maxKnockInterval = 0;

  

  for (i=0;i<maximumKnocks;i++){

    if (knockReadings[i] > 0){

      currentKnockCount++;

    }

    if (secretCode[i] > 0){

      secretKnockCount++;

    }

    

    if (knockReadings[i] > maxKnockInterval){

      maxKnockInterval = knockReadings[i];

    }

  }

  

  if (programButtonPressed==true){

      for (i=0;i<maximumKnocks;i++){

        secretCode[i]= map(knockReadings[i],0, maxKnockInterval, 0, 100); 

      }

      digitalWrite(greenLED, LOW);

      digitalWrite(redLED, LOW);

      delay(1000);

      digitalWrite(greenLED, HIGH);

      digitalWrite(redLED, HIGH);

      delay(50);

      for (i = 0; i < maximumKnocks ; i++){

        digitalWrite(greenLED, LOW);

        digitalWrite(redLED, LOW);  

        if (secretCode[i] > 0){                                   

          delay( map(secretCode[i],0, 100, 0, maxKnockInterval));

          digitalWrite(greenLED, HIGH);

          digitalWrite(redLED, HIGH);

        }

        delay(50);

      }

    return false;

  }

  

  if (currentKnockCount != secretKnockCount){

    return false; 

  }

  int totaltimeDifferences=0;

  int timeDiff=0;

  for (i=0;i<maximumKnocks;i++){

    knockReadings[i]= map(knockReadings[i],0, maxKnockInterval, 0, 100);      

    timeDiff = abs(knockReadings[i]-secretCode[i]);

    if (timeDiff > rejectValue){

      return false;

    }

    totaltimeDifferences += timeDiff;

  }

  if (totaltimeDifferences/secretKnockCount>averageRejectValue){

    return false; 

  }

  

  return true;

  

}