#include <Wire.h>
#include <U8g2lib.h>
#include <Encoder.h>

#define IGNITION_PIN 2
#define BUZZER_PIN 3
#define OUTPUT1_PIN 4
#define OUTPUT2_PIN 5
#define ENCODER_PIN_A 6
#define ENCODER_PIN_B 7
#define ENCODER_BUTTON_PIN 8

U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0);
Encoder encoder(ENCODER_PIN_A, ENCODER_PIN_B);

bool ignitionState = false;
bool timerRunning = false;
bool systemShutdown = false;
unsigned long timerStart = 0;
unsigned long timerDuration = 0;
unsigned long beepInterval = 0;
bool beepOn = false;
int timeSet = 120; // Default time set to 120 seconds

void setup() {
  pinMode(IGNITION_PIN, INPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(OUTPUT1_PIN, OUTPUT);
  pinMode(OUTPUT2_PIN, OUTPUT);
  pinMode(ENCODER_BUTTON_PIN, INPUT_PULLUP); // Use internal pull-up resistor
  digitalWrite(OUTPUT1_PIN, LOW);
  digitalWrite(OUTPUT2_PIN, LOW);
  
  Serial.begin(9600); // Start serial for debugging
  
  u8g2.begin();
  u8g2.clearBuffer();
  u8g2.setFont(u8g2_font_ncenB08_tr);
  
  // Initial display update
  displayMain();
}

void loop() {
  ignitionState = digitalRead(IGNITION_PIN);
  
  if (ignitionState && systemShutdown) {
    // Ignition turned on, reset system
    systemShutdown = false;
    timerRunning = false;
    displayMain();
  }
  
  if (!ignitionState && !timerRunning && !systemShutdown) {
    // Ignition turned off, start timer
    timerRunning = true;
    timerStart = millis();
    timerDuration = timeSet * 1000;
    beepInterval = millis();
    displayCountdown();
  }
  
  if (timerRunning) {
    unsigned long elapsed = millis() - timerStart;
    if (elapsed < timerDuration) {
      // Update display with countdown timer
      displayCountdown();
      // Handle beeping pattern
      if (millis() - beepInterval > 1000) { // Beep every 1 second
        beepInterval = millis();
        tone(BUZZER_PIN, 1000, 100); // Beep for 100ms
      }
    } else {
      // Timer ended
      timerRunning = false;
      systemShutdown = true;
      tone(BUZZER_PIN, 1000, 2000); // Beep for 2 seconds
      delay(2000);
      digitalWrite(OUTPUT1_PIN, LOW);
      digitalWrite(OUTPUT2_PIN, LOW);
      // Clear display to indicate shutdown
      u8g2.clearBuffer();
      u8g2.sendBuffer();
    }
  }
  
  // Handle encoder input for menu navigation
  if (digitalRead(ENCODER_BUTTON_PIN) == LOW && !timerRunning) {
    // Button pressed, enter menu
    Serial.println("Encoder button pressed");
    displayMenu();
  }
}

void displayMain() {
  u8g2.clearBuffer();
  char buffer[20];
  
  // Display set time
  sprintf(buffer, "Time Set: %d sec", timeSet);
  u8g2.drawStr(0, 20, buffer);
  
  u8g2.sendBuffer();
}

void displayCountdown() {
  u8g2.clearBuffer();
  char buffer[20];
  
  // Display countdown timer and bar graph
  unsigned long elapsed = millis() - timerStart;
  unsigned long remaining = (timerDuration - elapsed) / 1000;
  sprintf(buffer, "Time Left: %lu sec", remaining);
  u8g2.drawStr(0, 20, buffer);
  
  // Draw bar graph
  int barWidth = (128 * elapsed) / timerDuration;
  u8g2.drawFrame(0, 30, 128, 10);
  u8g2.drawBox(0, 30, barWidth, 10);
  
  u8g2.sendBuffer();
}

void displayMenu() {
  u8g2.clearBuffer();
  u8g2.drawStr(0, 20, "Set Time:");
  char buffer[20];
  sprintf(buffer, "%d sec", timeSet);
  u8g2.drawStr(0, 40, buffer);
  u8g2.sendBuffer();
  
  // Adjust time set using encoder
  long encoderPos = encoder.read();
  timeSet += encoderPos / 4; // Adjust based on encoder steps
  if (timeSet < 1) timeSet = 1;
  if (timeSet > 300) timeSet = 300;
  encoder.write(0); // Reset encoder position
}