/*
  Automated traffic light system that allows
  interrupts for pedestrians.
*/

bool ButtonPressed = 0;
bool executed = LOW;
bool canInterrupt = HIGH;
volatile bool changed = LOW;

const int INT_Pin1 = 3;
const int INT_NO = 1;



void setup()
{
  Serial.begin(9600);
  pinMode(8, OUTPUT); // Red Light
  pinMode(9, OUTPUT); // Amber Light
  pinMode(10, OUTPUT); // Green Light
  pinMode(12, OUTPUT); // Pedestrian Red
  pinMode(13, OUTPUT); // Pedrestrian Green
  pinMode(3, INPUT); // Button
  attachInterrupt(INT_NO, changedInt, FALLING);
}

void changedInt() {
  Serial.write("Interrupt1");
  if (canInterrupt) {
    changed = HIGH;
    Serial.write("Interrupt2");
  }

}

void changeLights() {
  changed = LOW;
  // Turn on the amber light and turn off the green light.
  digitalWrite(10, LOW);
  digitalWrite(9, HIGH);
  delay(3000); // Wait 3 seconds for the amber light to stay on.

  // Turn off amber light, turn on the red light and turn on green pedestrian light.
  digitalWrite(12, LOW);
  digitalWrite(9, LOW);
  digitalWrite(8, HIGH);
  digitalWrite(13, HIGH);
  delay(10000);

  // Flashing Stage: amber and green pedestrian light flash for 5 seconds, each is 0.5s
  digitalWrite(8, LOW);
  canInterrupt = HIGH; // Allows the interrupt to change the "changed" variable to indicate the button has been pressed
  for (int i = 0; i < 5; i++) { // Loops through 5 times, to cause the lights to flash on and off with a 500ms delay between each flash
    digitalWrite(9, LOW);
    digitalWrite(13, LOW); // Turn off

    delay(500);

    digitalWrite(9, HIGH);
    digitalWrite(13, HIGH); // Turn on for Flash
    delay(500);

  }
  if (changed) { // Converts the changed signal from the interrupt into a button push for the if statement
    ButtonPressed = HIGH;
  } else {
    ButtonPressed = LOW;
  }
  digitalWrite(9, LOW);
  digitalWrite(8, LOW);
  digitalWrite(13, LOW);
  executed = HIGH;
}



void loop() {
  digitalWrite(10, HIGH);
  digitalWrite(12, HIGH);
  if (executed) { // Checks that the program was previously executed so to use the 60 second delay. Otherwise there is no delay at the start of the program.
    executed = LOW;
    digitalWrite(10, HIGH);
    digitalWrite(12, HIGH);
    canInterrupt = LOW;
    delay(10000);
  }

  if (ButtonPressed) {
    changeLights();
  } else {
    ButtonPressed = digitalRead(3);
  }

}