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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

const int ME3_PIN = 34;
const int MQ3_PIN = 35;
const int BUTTON_PIN = 18;
const int LED_GREEN = 25;
const int LED_YELLOW = 26;
const int LED_RED = 27;

bool systemActive = false;

void setup() {
  Serial.begin(115200);
  pinMode(LED_GREEN, OUTPUT);
  pinMode(LED_YELLOW, OUTPUT);
  pinMode(LED_RED, OUTPUT);
  pinMode(BUTTON_PIN, INPUT_PULLUP);

  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.display();
}

void loop() {
  // Đọc công tắc
  if (digitalRead(BUTTON_PIN)) {
    systemActive = !systemActive;
    delay(300); // Chống nhiễu
  }

  if (systemActive) {
    float ethylene = analogRead(ME3_PIN) * (3.3 / 4095.0);
    float alcohol = analogRead(MQ3_PIN) * (3.3 / 4095.0);

    // Điều khiển LED
    digitalWrite(LED_GREEN, (ethylene < 1.0 && alcohol < 0.5) ? HIGH : LOW);
    digitalWrite(LED_YELLOW, (ethylene >= 1.0 && alcohol < 1.0) ? HIGH : LOW);
    digitalWrite(LED_RED, (alcohol >= 1.0) ? HIGH : LOW);

    // Hiển thị OLED
    display.clearDisplay();
    display.setCursor(0, 0);
    display.print("Ethylene: ");
    display.println(ethylene, 2);
    display.print("Alcohol: ");
    display.println(alcohol, 2);
    display.print("Status: ");
    if (digitalRead(LED_GREEN)) display.println("UNRIPE");
    else if (digitalRead(LED_YELLOW)) display.println("RIPE");
    else display.println("OVERRIPE");
    display.display();
  } else {
    digitalWrite(LED_GREEN, LOW);
    digitalWrite(LED_YELLOW, LOW);
    digitalWrite(LED_RED, LOW);
    display.clearDisplay();
    display.setCursor(30, 28);
    display.print("SYSTEM OFF");
    display.display();
  }
  delay(500);
}