/*
Lab 2 Challenging Content

Vraj Patel, Makeda Morrison
Lab Section: MAE 311-01
Due Date: June 23, 2025
*/

const int switchPin = 2;  // monitors pin 2
const int ledPin = 11;  // The LED is on pin 11
int buttonState;  // Remembers state of the button
int lightState = 0;  // Remembers state of the LED (starts off)
int blinkState = LOW;  // stores initial state of blinking LED
long previousMillis = 0;  // stores last time the LED was updated
long interval = 1000;  // blinking interval in milliseconds
unsigned long currentMillis = 0;  // start the timer at 0
int blinkStrength;  // PWM strength variable for State 2

void setup() {
  pinMode(switchPin, INPUT);  // Set the switch pin as input
  pinMode(ledPin, OUTPUT);  // Set the LED pin as an output
  Serial.begin(9600);  // Set up serial communication at 9600 bps
  buttonState = digitalRead(switchPin);  // read the initial state
}

void loop() {
  int val = digitalRead(switchPin);  // read input value and store it in val
  delay(10);  // waits 10 milliseconds to read the switch again
  int val2 = digitalRead(switchPin);  // second read of the switch
  if (val == val2) {  // ensure it was really a press
    if (val != buttonState) {  // The button state has changed
      if (val == LOW) {  // check if the button is being pressed 
        if (lightState == 0) {  // check if the light is off
          lightState = 1;  // set the blink mode to ON
          Serial.println("Button just pressed, Blinking");
          currentMillis = 0;  // sets the start time to 0
          previousMillis = 0;  // sets the current time to zero
          blinkState = LOW;  // ensures that the LED variable is off
        }
        else if (lightState == 1) {
          lightState = 2;
          Serial.println("Button pressed again, long blinks");
        }
        else if (lightState == 2) {
          lightState = 3;
          digitalWrite(ledPin, HIGH);
          Serial.println("Button pressed again, continuously on");
          Serial.print(lightState);
        }
        else if (lightState == 3) {  // button pressed in State 3, go back to initial off state
          lightState = 0;  // sets the state to OFF
          digitalWrite(ledPin, LOW);  // turn LED off
          blinkState = LOW;  // set the led variable off
          Serial.println("Button just pressed, light off");
        }
      }
   }
  }

//    BLINKING SECTION START //

if (lightState == 1) {  // if the blink mode is active, do this
  currentMillis = millis();  // record the current time
  if (currentMillis - previousMillis > interval) {  // compare start and current time, only execute if greater than set blink interval time
    previousMillis = currentMillis;  // set the timer equal since blink interval is reached
    if (blinkState == LOW)  // if the led is off, then
      blinkState = HIGH;  // turn it on
      else 
        blinkState = LOW;  // turn it off
      digitalWrite(ledPin, blinkState);  // actually turns it off or on
    }
  }

//   BLINKING SECTION END   //
  buttonState = val;  // save the new state in our variable

}