#include <string.h>
#include <LiquidCrystal_I2C.h>
#include "DHTesp.h"
#include <WiFi.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>

#define DHT_PIN 15 // DHT connect to pin 15
#define LED_PIN 32 // LED connect to pin 32
#define PIR_SENSOR 12 // PIR connect to pin 12
DHTesp dhtSensor;

// Set the LCD address to 0x27, 
LiquidCrystal_I2C lcd(0x27, 16, 2);
// Use timestamp to print DHT 
unsigned long previousMillis = 0;
const long interval = 2000;

// Server Address
String serverName = "https://postman-echo.com/";
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);

  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);

  // config led pin
  pinMode(LED_PIN, OUTPUT);
  // Config PIR 
  pinMode(PIR_SENSOR, INPUT);
  Serial.print("Connecting to WiFi");
  //setup for WiFi connection
  WiFi.begin("Wokwi-GUEST", "", 6);
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println("WiFi Connected!");
  Serial.print("ESP32 collecting sensors data\n");

  lcd.init(); // initialize the lcd 
  // Print a message to the LCD.
  lcd.backlight();
  lcd.setCursor(1,0);
  lcd.print("ESP32 collecting data ...");
  delay(1000);
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(dhtSensor.getMinimumSamplingPeriod()); // this speeds up the simulation
  
  float humidity = dhtSensor.getHumidity();
  float temperature = dhtSensor.getTemperature();

  Serial.print("Humidity: ");
  Serial.println(humidity);
  Serial.print("Temperature: ");
  Serial.println(temperature);
  const long currentMillis = millis();
  if(currentMillis - previousMillis >= interval){
    previousMillis = currentMillis;
    DHT_Handle(humidity, temperature);
    Send_GET_URLENCODE(humidity, temperature);
    Send_POST_URLENCODE(humidity, temperature);
    Send_POST_Body(humidity, temperature);
  }
  
  int pir_value = digitalRead(PIR_SENSOR);
  if(pir_value == 1){
    digitalWrite(LED_PIN, HIGH);
    Serial.println("Motion detected. LED is ON.");
  } else {
    digitalWrite(LED_PIN, LOW);
    Serial.println("Motion ended. LED is OFF");
  }
}

void DHT_Handle(float humidity, float temperature){
  lcd.init(); // initialize the lcd 
  // Print a message to the LCD.
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.setCursor(0, 1);
  lcd.print("Temperature: ");
  lcd.print(temperature);
  lcd.print("C");
}


// a. Send HTTP GET, 
void Send_GET_URLENCODE(float humidity, float temperature){
    if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String serverPath = serverName + "get?temp=" + String(temperature) + "&humid=" + String(humidity);     
    http.begin(serverPath.c_str()); // Send HTTP GET request 
    int httpResponseCode = http.GET();
    if (httpResponseCode > 0) {
      Serial.print("HTTP Response code: "); Serial.println(httpResponseCode);
      String payload = http.getString();
      Serial.println(payload);
    }
    else {
      Serial.print("Error code: "); Serial.println(httpResponseCode);
    }
    http.end();
  }
  else {
    Serial.println("WiFi Disconnected");
  }
}

// b. Send HTTP POST Urlencode
void Send_POST_URLENCODE(float humidity, float temperature){
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String serverPath = serverName + "post";
    http.begin(serverPath);
    http.addHeader("Content-Type", "application/x-www-form-urlencoded");
    String httpRequestData = "&temp=" + String(temperature) + "&humid=" + String(humidity);
    Serial.println(httpRequestData);
    int httpResponseCode = http.POST(httpRequestData);

    if (httpResponseCode > 0) {
      Serial.print("HTTP Response code: "); Serial.println(httpResponseCode);
      String payload = http.getString();
      Serial.println(payload);
    }
    else {
      Serial.print("Error code: "); Serial.println(httpResponseCode);
    }
    http.end();
  }
  else {
    Serial.println("WiFi Disconnected");
  }
}

// c. Send HTTP POST Body
void Send_POST_Body(float humidity, float temperature){
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String serverPath = serverName + "post";
    http.begin(serverPath);
    http.addHeader("Content-Type", "application/json");
    String httpRequestData = "{\"temp\": " + String(temperature) + ", \"humid\": " + String(humidity) + "}";
    Serial.println(httpRequestData);
    int httpResponseCode = http.POST(httpRequestData);

    if (httpResponseCode > 0) {
      Serial.print("HTTP Response code: "); Serial.println(httpResponseCode);
      String payload = http.getString();
      Serial.println(payload);
    }
    else {
      Serial.print("Error code: "); Serial.println(httpResponseCode);
    }
    http.end();
  }
  else {
    Serial.println("WiFi Disconnected");
  }
}