/*
   ============================================================
      0.96" OLED SPI versiyasi (SSD1306 SPI) PIN TA’RIFLARI
   ============================================================

   FIZIK OLED PINOUT:

   1) GND   → Arduino GND
   2) VCC   → Arduino 5V yoki 3.3V
   3) D0    → SCK (SPI clock)  → Arduino pin 13
   4) D1    → MOSI (SPI data)  → Arduino pin 11
   5) RES   → Reset             → Arduino pin 10
   6) DC    → Data/Command      → Arduino pin 9
   7) CS    → Chip Select       → Arduino pin 8

   OLED modeli: SPI (I2C emas!)
*/

#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

// OLED SPI pinlari (SSD1306 SPI)
#define OLED_MOSI   11
#define OLED_CLK    13
#define OLED_DC      9
#define OLED_CS      8
#define OLED_RST    10

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &SPI, OLED_DC, OLED_RST, OLED_CS);

// Tugmalar
#define BTN_GREEN  3     // Sanash tugmasi (GND ga ulangan, pulldown)
#define BTN_YELLOW 4     // Reset tugmasi (INPUT_PULLUP)
#define BUZZER_PIN 2

unsigned long counter = 0;
unsigned long MAX_COUNT = 100000;
unsigned long STEP_ALERT = 25000;

bool lastGreenState = HIGH;

void setup() {
  Serial.begin(9600);
  Serial.println("Tizim yuklanmoqda...");

  pinMode(BTN_GREEN, INPUT);         // pulldown
  pinMode(BTN_YELLOW, INPUT_PULLUP); 
  pinMode(BUZZER_PIN, OUTPUT);

  SPI.begin();

  if (!display.begin(SSD1306_SWITCHCAPVCC)) {
    Serial.println("OLED topilmadi!");
    while (true);
  }

  display.clearDisplay();
  display.setTextColor(WHITE);
  display.setTextSize(2);
  display.display();

  showCounter();

  Serial.println("Tizim tayyor.");
}

void loop() {

  bool greenState = digitalRead(BTN_GREEN);

  // ======== BOSILGAN ONI (faqat bir marta +1) =========
  if (lastGreenState == HIGH && greenState == LOW) {

    if (counter < MAX_COUNT) {
      counter++;

      // *** 25000, 50000, 75000, 100000 da ogohlantirish ***
      if (counter % STEP_ALERT == 0) {
        tone(BUZZER_PIN, 1200, 1000);
        Serial.print("Ogohlantirish → ");
        Serial.println(counter);
      }
    }

    showCounter();
    delay(120);
  }

  lastGreenState = greenState;

  // ========= RESET TUGMA =========
  if (digitalRead(BTN_YELLOW) == LOW) {
    counter = 0;
    Serial.println("RESET → Hisob 0 ga qaytdi.");
    showCounter();
    delay(150);
  }
}

void showCounter() {
  display.clearDisplay();

  display.setCursor(25, 0);
  display.setTextSize(2);
  display.print("Hisob:");

  display.setCursor(10, 25);
  display.setTextSize(3);
  display.println(counter);

  display.display();

  Serial.print("Hisob = ");
  Serial.println(counter);
}