#include <Arduino.h>

// Define GPIO pins
const int relayPin = 23;  // Relay pin
const int ledPin = 22;    // LED pin
const int buzzerPin = 21; // Buzzer pin

const unsigned long firstPhaseDuration = 10000; // 10 seconds
const unsigned long secondPhaseDuration = 4000;  // 4 seconds (10 to 14 seconds)
const unsigned long totalCountdownDuration = 24000; // Total 24 seconds
const unsigned long relayDuration = 5000; // Relay active for 5 seconds

void setup() {
    // Initialize serial monitor
    Serial.begin(115200);
    
    // Set pin modes
    pinMode(relayPin, OUTPUT);
    pinMode(ledPin, OUTPUT);
    pinMode(buzzerPin, OUTPUT);
    
    // Make sure relay and buzzer are off initially
    digitalWrite(relayPin, LOW);
    digitalWrite(buzzerPin, LOW);
}

void loop() {
    // Indicate start of the system
    Serial.println("Starting system...");
    
    // Loud double beep at the start
    for (int i = 0; i < 2; i++) {
        tone(buzzerPin, 1000, 200); // Beep for 200 ms
        delay(300); // Wait between beeps
    }
    
    // Phase 1: First 10 seconds
    digitalWrite(ledPin, HIGH); // LED ON
    for (int i = 0; i < 2; i++) { // Double beep
        tone(buzzerPin, 1000, 200); // Beep for 200 ms each
        delay(300); // Wait between beeps
    }
    delay(firstPhaseDuration - 400); // Wait for remaining time (10 sec total)
    
    // Phase 2: Next 4 seconds (10 to 14 seconds)
    Serial.println("Starting countdown for next 4 seconds...");
    
    // Fast blinking LED for the next 4 seconds
    unsigned long startTime = millis();
    while (millis() - startTime < secondPhaseDuration) {
        digitalWrite(ledPin, HIGH); // LED ON
        delay(200); // Short ON time
        digitalWrite(ledPin, LOW); // LED OFF
        delay(200); // Short OFF time
    }
    
    // Continuous beep during the blinking
    tone(buzzerPin, 1000); // Start continuous beep

    // Final countdown for 14 to 24 seconds
    Serial.println("Starting final countdown...");
    delay(totalCountdownDuration - firstPhaseDuration - secondPhaseDuration); // Wait for remaining time (24 sec total)
    
    // LED fast blink from 14 to 24 seconds
    startTime = millis();
    while (millis() - startTime < relayDuration) {
        digitalWrite(ledPin, HIGH); // LED ON
        delay(200); // Short ON time
        digitalWrite(ledPin, LOW); // LED OFF
        delay(200); // Short OFF time
    }

    // Activate relay for 5 seconds
    Serial.println("Ejecting parachute!");
    digitalWrite(relayPin, HIGH); // Activate relay
    delay(relayDuration); // Keep activated for 5 seconds
    digitalWrite(relayPin, LOW); // Deactivate relay
    Serial.println("Parachute ejection complete.");
    
    // Reset and stop
    digitalWrite(ledPin, LOW); // Ensure LED is OFF
    noTone(buzzerPin); // Ensure buzzer is OFF
    while (true); // Stop the loop
}