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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define DHTPIN 15
#define DHTTYPE DHT22
#define TRIG_PIN 25
#define ECHO_PIN 26
#define BUZZER_PIN 35

const int redLED = 32;
const int yellowLED = 33;
const int greenLED = 34;

DHT dht(DHTPIN, DHTTYPE);
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

const float tempRisk = 70.0;  //danger Temperature
const float humidityRisk = 20.0; //danger Humidity

void setup() {
  Serial.begin(115200);
  dht.begin();
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.clearDisplay();

  pinMode(redLED, OUTPUT);
  pinMode(yellowLED, OUTPUT);
  pinMode(greenLED, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
}

long measureDistance() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  return pulseIn(ECHO_PIN, HIGH) * 0.034 / 2;
}

void loop() {
  delay(500);
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  long distance = measureDistance();

  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.print("｡C\t");
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  digitalWrite(redLED, LOW);
  digitalWrite(yellowLED, LOW);
  digitalWrite(greenLED, LOW);

  if (t > tempRisk && h < humidityRisk) {
    display.clearDisplay();
    display.setTextSize(2);
    display.setTextColor(SSD1306_WHITE);
    display.setCursor(0, 0);
    display.print("very        danger!!");
    display.display();

    digitalWrite(redLED, HIGH);
  } else {
    if (t >= 60.0 && t <= 80.0) {
      digitalWrite(redLED, HIGH);
    } else if (t >= 37.0 && t < 60.0) {
      digitalWrite(yellowLED, HIGH);
    } else if (t < 37.0) {   //normal Temperature
      digitalWrite(greenLED, HIGH);
    }

    if (h < 20.0) {
      digitalWrite(redLED, HIGH);
    } else if (h < 50.0) {
      digitalWrite(yellowLED, HIGH);
    } else {       //normal Humidity
      digitalWrite(greenLED, HIGH);
    }

    display.clearDisplay();
    display.setTextSize(1);
    display.setTextColor(SSD1306_WHITE);
    display.setCursor(0, 0);
    display.print("Humidity: ");
    display.print(h);
    display.print(" %");
    display.setCursor(0, 10);
    display.print("Temperature: ");
    display.print(t);
    display.print(" °C");
    display.setCursor(0, 20);
    display.print("Distance: ");
    display.print(distance);
    display.print(" cm");
    display.display();
  }

  if (t > tempRisk || h < humidityRisk) {
    tone(32, 1000, 500); //32pin 1000Hz 500ms
  }
}