// source http://www.instructables.com/id/Home-Security-Alarm-or-a-Motion-Detector-Using-Ard/
// Source photo cell https://learn.adafruit.com/photocells/using-a-photocell
// Source speaker http://www.instructables.com/id/Home-Security-Alarm-or-a-Motion-Detector-Using-Ard/

// library for the LCD display:
#include <LiquidCrystal.h>

int ledPin = 11;               
int PIRpin = 8;            
int pirState = LOW;            
int val = 0;                    
// photocell circuit
int photocellPin = 0;     // the cell and 10K pulldown are connected to a0
int photocellReading;     // the analog reading from the sensor divider         
int pinSpeaker = 10;  // must be a pwm pin (9, 10 or 11)

LiquidCrystal lcd(2, 3, 4, 5, 6, 7);                        


void setup() {  

  pinMode(ledPin, OUTPUT);       
  pinMode(PIRpin, INPUT);     
  pinMode(photocellPin, INPUT);
  pinMode(pinSpeaker, OUTPUT);
    
  Serial.begin(9600);
  lcd.begin(16, 2); 
  lcd.setCursor(2, 0);                   	// Set LCD cursor position (column, row)
  lcd.print("P.I.R Motion ");               // Print text to LCD
  lcd.setCursor(0, 1);                      // Set LCD cursor position (column,row) 
  lcd.print("and Light Sensors");           // Print text to LCD
  delay(2000); // wait 2s                   // Delay to read text
                                                              
	lcd.clear();                            // Clear LCD    
	lcd.setCursor(0, 0); 
    lcd.print("Processing Data.");
	playTone(300, 300);
	delay(150);
	playTone(0, 0);
    delay(3000);
    lcd.clear(); 
    lcd.setCursor(3, 0);
    lcd.print("Waiting For");
    lcd.setCursor(3, 1);
    lcd.print("Motion....");   
	delay(150);	
  
}

void loop(){
  val = digitalRead(PIRpin);  
  photocellReading = analogRead(photocellPin);

  if (val == HIGH) {            // check if the input is HIGH
    digitalWrite(ledPin, HIGH);  // turn LED ON


    if (pirState == LOW) {
      // we have just turned on
      Serial.println("Motion detected!");
	
      lcd.clear() ;
      lcd.setCursor(0, 0);                 // Set LCD cursor position (column 0, row 0)
      lcd.print("Motion Detected!");   
      lcd.setCursor(0, 1);                 // Set LCD cursor position (column 0, row 1)
      lcd.print(photocellReading);      
      // We only want to print on the output change, not state
      playTone(300, 300);
	  delay(150);
	  playTone(0, 0);
	  
      pirState = HIGH;

      // delay(5000);    // when motion display info during 5 seconds
    }
  } else {
      digitalWrite(ledPin, LOW); // turn LED OFF
      delay(300);    

	  // display no motion screen saver
	  scrollScreenSaver() ;	 
	  
      if (pirState == HIGH){
		// we have just turned of
		Serial.println("Motion ended!");
        pirState = LOW;
    }
  }
}

// duration in mSecs, frequency in hertz
void playTone(long duration, int freq) {
    duration *= 1000;
    int period = (1.0 / freq) * 100000;
    long elapsed_time = 0;
    while (elapsed_time < duration) {
        digitalWrite(13, HIGH);
    digitalWrite(pinSpeaker,HIGH);
        delayMicroseconds(period / 2);
        digitalWrite(13, LOW);
    digitalWrite(pinSpeaker, LOW);
        delayMicroseconds(period / 2);
        elapsed_time += (period);
    }
}

void scrollScreenSaver() {
	
	// autoscroll https://www.arduino.cc/en/Tutorial/LiquidCrystalAutoscroll
	lcd.clear() ;
  	lcd.setCursor(15, 0);                 // Set LCD cursor position (column 0, row 0)
	lcd.print("No Motion ");   
	lcd.setCursor(15, 1); 
	lcd.print("Waiting !");	
	// scroll 7 positions (display length - string length) to the left
	// to move it back to center:
	
    for (int positionCounter = 0; positionCounter < 22; positionCounter++) {
		// scroll one position left:
		lcd.scrollDisplayLeft();
		// wait a bit:
		delay(150);
    
	}
}