#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <LiquidCrystal_I2C.h>
#include <Adafruit_NeoPixel.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
LiquidCrystal_I2C lcd(0x27, 16, 2);

#define PIR_PIN 13
#define TRIG_PIN 12
#define ECHO_PIN 14

#define BUZZER_A 25
#define NEO_A 26

#define BUZZER_B 33
#define NEO_B 27

#define NUM_LEDS 16
Adafruit_NeoPixel ringA(NUM_LEDS, NEO_A, NEO_GRB + NEO_KHZ800);
Adafruit_NeoPixel ringB(NUM_LEDS, NEO_B, NEO_GRB + NEO_KHZ800);

int virtualDistance = 180;
bool enemyApproaching = true;
unsigned long prevAutoMillis = 0;
const long enemySpeedInterval = 250; 

unsigned long prevBuzzerMillis = 0;
bool buzzerToggle = false;

void setup() {
  Serial.begin(115200);
  pinMode(PIR_PIN, INPUT);
  
  ledcAttach(BUZZER_A, 1200, 8); 
  ledcAttach(BUZZER_B, 1200, 8); 
  
  if(!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { Serial.println("OLED Link Error"); }
  lcd.init();
  lcd.backlight();
  
  ringA.begin(); ringA.show();
  ringB.begin(); ringB.show();
  
  lcd.setCursor(0, 0); lcd.print("GRID INITIALIZED");
  lcd.setCursor(0, 1); lcd.print("RADAR VISUAL OK ");
  delay(1500);
}

void loop() {
  unsigned long currentMillis = millis();

  if (currentMillis - prevAutoMillis >= enemySpeedInterval) {
    prevAutoMillis = currentMillis;
    if (enemyApproaching) {
      virtualDistance -= 5;
      if (virtualDistance <= 15) enemyApproaching = false;
    } else {
      virtualDistance += 5;
      if (virtualDistance >= 180) enemyApproaching = true;
    }
  }

  oled.clearDisplay();
  drawFuturisticRadarUI(virtualDistance);

  setRingColor(ringA, 0, 255, 0); 
  setRingColor(ringB, 0, 255, 0); 

  if (virtualDistance < 150) {
    if (virtualDistance > 80 && virtualDistance <= 150) {
      ledcWrite(BUZZER_B, 0); 
      setRingColor(ringA, 255, 100, 0); 
      
      lcd.setCursor(0, 0); lcd.print("ALERT: SECTOR A ");
      lcd.setCursor(0, 1); lcd.print("ENEMY: " + String(virtualDistance) + "cm     ");
      
      if (currentMillis - prevBuzzerMillis >= 250) {
        prevBuzzerMillis = currentMillis;
        buzzerToggle = !buzzerToggle;
      }
      
      if(buzzerToggle) {
        ledcWrite(BUZZER_A, 128); 
      } else {
        ledcWrite(BUZZER_A, 0);   
      }
    } 
    else if (virtualDistance <= 80) {
      setRingColor(ringA, 255, 0, 0); 
      setRingColor(ringB, 255, 0, 0); 
      
      lcd.setCursor(0, 0); lcd.print("🚨 BREACH: ZONE B");
      lcd.setCursor(0, 1); lcd.print("CTRL ROOM IMPACT");
      
      ledcWrite(BUZZER_A, 128); 
      ledcWrite(BUZZER_B, 128); 
    }
  } else {
    ledcWrite(BUZZER_A, 0);
    ledcWrite(BUZZER_B, 0);
    lcd.setCursor(0, 0); lcd.print("GRID ONLINE:    ");
    lcd.setCursor(0, 1); lcd.print("SYSTEM SECURE   ");
  }

  oled.display();
}

void drawFuturisticRadarUI(int distance) {
  // Radar Semicircle Arcs
  oled.drawCircle(64, 63, 60, WHITE); 
  oled.drawCircle(64, 63, 38, WHITE); 
  
  // Center Control Room Core Circle (Radius 14)
  oled.drawCircle(64, 63, 14, WHITE); 
  oled.drawLine(4, 63, 124, 63, WHITE); 
  
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  
  // 📍 EXACT TARGET ALIGNMENT: Sectors are positioned right above the central Control Room Circle Line!
  oled.setCursor(24, 44); oled.print("Sec A"); // Left side just above the core arc boundary
  oled.setCursor(76, 44); oled.print("Sec B"); // Right side just above the core arc boundary
  
  // Control Room core mark centered inside its circle
  oled.setCursor(53, 52); oled.print("CTRL"); 
  
  if (distance < 150) {
    int mappedRadius = map(constrain(distance, 10, 150), 10, 150, 10, 58);
    oled.fillCircle(64, 63 - mappedRadius, 3, WHITE); 
    oled.drawCircle(64, 63 - mappedRadius, 6, WHITE); 
    
    oled.setCursor(2, 4); oled.print(String(distance) + "cm");
  } else {
    oled.setCursor(2, 4); oled.print("SCAN");
  }
}

void setRingColor(Adafruit_NeoPixel &targetRing, uint8_t r, uint8_t g, uint8_t b) {
  for(int i=0; i<NUM_LEDS; i++) {
    targetRing.setPixelColor(i, targetRing.Color(r, g, b));
  }
  targetRing.show();
}