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

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

const int analogPin = 35;  // A3
const int digitalPin = 2;  // D2

void setup() {
  Serial.begin(9600);
  pinMode(digitalPin, INPUT);

  // SSD1306 OLED display initialization
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.display();
  delay(2000); // Pause for 2 seconds
  display.clearDisplay();
}

void loop() {
  int analogValueRaw = analogRead(analogPin);
  int analogValue = map(analogValueRaw, 0, 4095, 0, 1023);  // Scale the value to match the Pico's range
  int digitalValue = digitalRead(digitalPin);
  String airQuality = getAirQuality(analogValue);

  Serial.print("Analog Value (Raw): ");
  Serial.print(analogValueRaw);
  Serial.print(", Scaled Value: ");
  Serial.print(analogValue);
  Serial.print(", Digital Value: ");
  Serial.println(digitalValue);

  // Display scaled analog value and air quality condition on OLED
  display.clearDisplay();
  display.setTextSize(2);      // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE); // Draw white text
  display.setCursor(0, 10);    // Start at top-left corner
  display.print("Value: ");
  display.println(analogValue);

  display.setTextSize(1);
  display.setCursor(0, 40);
  display.print("Air Quality: ");
  display.println(airQuality);

  display.display();
  delay(1000);
}

String getAirQuality(int analogValue) {
  if (analogValue <= 200) {
    return "Excellent";
  } else if (analogValue <= 400) {
    return "Good";
  } else if (analogValue <= 600) {
    return "Moderate";
  } else if (analogValue <= 800) {
    return "Poor";
  } else {
    return "Very Poor";
  }
}