#include <WiFi.h>
#include <WiFiClient.h>
#include <WebServer.h>

#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""

WebServer server(80);

int LED1 = 26;
int trig = 17;
int echo = 16;

float distance;
float duration;

void setup(void) {
  Serial.begin(115200);
  pinMode(LED1, OUTPUT);

  pinMode(trig, OUTPUT);
  pinMode(echo, OUTPUT);

  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  Serial.print("Connecting to WiFi ");
  Serial.print(WIFI_SSID);

  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println(" Connected!");

  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());

  server.on("/on", ledOn);
  server.on("/off", ledOff);
  server.on("/getDistance", returnDistance);

  server.begin();
  Serial.println("HTTP server started");
}

void loop(void) {
  server.handleClient();
  delay(2);
}

void ledOn(){
  digitalWrite(LED1, HIGH);
  server.send(200, "text/plain", "LED ON");
}

void ledOff(){
  digitalWrite(LED1, LOW);
  server.send(200, "text/plain", "LED OFF");
}

void returnDistance(){

  digitalWrite(trig, LOW);
  delayMicroseconds(2);
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, LOW);
  duration = pulseIn(echo, HIGH);
  distance = duration * 0.034 / 2;
  String msg = String(distance) + " cm";
  server.send(200, "text/plain", msg);
  
}