// MINIMAL OPTIMIZED VERSION - FITS IN 32KB FLASH
// Automated Energy-Saving Lighting System
// Group 21 - EEE320

// ============ PIN DEFINITIONS ============
#define PIR_PIN PA1     // Motion sensor input
#define LDR_PIN PA0     // Light sensor input  
#define LED1_PIN PA5    // Main light
#define LED2_PIN PA6    // Backup light

// ============ VARIABLES ============
int darkThreshold = 50;
bool motion = false;
bool dark = false;
int lightLevel = 0;

void setup() {
  Serial.begin(115200);
  
  // Initialize pins
  pinMode(LED1_PIN, OUTPUT);
  pinMode(LED2_PIN, OUTPUT);
  pinMode(PIR_PIN, INPUT);
  pinMode(LDR_PIN, INPUT_ANALOG);
  
  // Initial state
  digitalWrite(LED1_PIN, LOW);
  digitalWrite(LED2_PIN, LOW);
  
  Serial.println("System Ready");
  Serial.println("Format: Motion|Dark|LDR|Action");
  Serial.println("------------------------------");
}

void loop() {
  // Read sensors
  motion = digitalRead(PIR_PIN);
  lightLevel = analogRead(LDR_PIN);
  dark = (lightLevel > darkThreshold);
  
  // AND Logic
  if (motion && dark) {
    digitalWrite(LED1_PIN, HIGH);
    digitalWrite(LED2_PIN, HIGH);
    Serial.print("MOTION:YES DARK:YES LDR:");
    Serial.print(lightLevel);
    Serial.println(" -> LIGHTS ON (Energy Saving Active)");
  } else {
    digitalWrite(LED1_PIN, LOW);
    digitalWrite(LED2_PIN, LOW);
    Serial.print("MOTION:");
    Serial.print(motion ? "YES" : "NO ");
    Serial.print(" DARK:");
    Serial.print(dark ? "YES" : "NO ");
    Serial.print(" LDR:");
    Serial.print(lightLevel);
    Serial.println(" -> LIGHTS OFF");
  }
  
  delay(1000);
}