/// mussel_mood.ino - Button-controlled LED system with state tracking
///
/// SPDX-License-Identifier: GPL-3.0-or-later
/// SPDX-FileCopyrightText: 2025 Tanishka Suwalka <tanishkas@ruc.dk>
///
/// This code toggles LEDs based on button presses, cycling through Red, Green, and Yellow states.

const int buttonPin = 9;      
const int redLED = 3;         
const int greenLED = 4;       
const int yellowLED = 5;      

int buttonState = HIGH;       
int lastButtonState = HIGH;   
int clickCount = 0;           
unsigned long lastDebounceTime = 0; 
const unsigned long debounceDelay = 50; 

void setup() {
    pinMode(buttonPin, INPUT_PULLUP); // Enable internal pull-up resistor for button
    pinMode(redLED, OUTPUT);
    pinMode(greenLED, OUTPUT);
    pinMode(yellowLED, OUTPUT);
    Serial.begin(9600); // Initialize serial monitor for debugging
}

void loop() {
    int reading = digitalRead(buttonPin); // Read button state

    // Debounce logic: Ensures a single press isn't detected multiple times
    if (reading != lastButtonState) {
        lastDebounceTime = millis(); // Reset debounce timer
    }

    if ((millis() - lastDebounceTime) > debounceDelay) {
        // Check for button press (transition from HIGH to LOW)
        if (reading == LOW && lastButtonState == HIGH) {
            clickCount++; // Increment click count
            if (clickCount > 3) {
                clickCount = 0; // Reset cycle after 3 clicks
            }
            updateLEDs();
        }
    }

    lastButtonState = reading; // Update button state
}

/// updateLEDs() - Updates LED states based on click count
void updateLEDs() {
    // Turn off all LEDs first
    digitalWrite(redLED, LOW);
    digitalWrite(greenLED, LOW);
    digitalWrite(yellowLED, LOW);

    // Determine which LED to turn on
    switch (clickCount) {
        case 1:
            digitalWrite(redLED, HIGH);
            Serial.println("State: Angry (Red LED ON)");
            break;
        case 2:
            digitalWrite(greenLED, HIGH);
            Serial.println("State: Happy (Green LED ON)");
            break;
        case 3:
            digitalWrite(yellowLED, HIGH);
            Serial.println("State: Unsure (Yellow LED ON)");
            break;
        case 0:
            Serial.println("State: Off (All LEDs OFF)");
            break;
    }
}