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

#define DHT_PIN 15               
#define LED_PIN 32                

DHTesp dhtSensor;               
LiquidCrystal_I2C lcd(0x27, 16, 2);

const char* ssid = "Wokwi-GUEST";       
const char* password = "";   

const char* serverUrl = "https://postman-echo.com/post";  

/*const char* serverUrl = "https://postman-echo.com/get";*/  


void setup() {
  Serial.begin(9600);
  Serial.println("ESP32 collecting sensor data");

  lcd.init();                   
  lcd.backlight();            
  lcd.setCursor(1, 0);         
  lcd.print("ESP32 collecting data ..."); 

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

  connectToWiFi();

  delay(1000);
}

void loop() {
  lcd.clear();

  TempAndHumidity data = dhtSensor.getTempAndHumidity();
  int temp = data.temperature;  
  int humid = data.humidity;    

  String stemp = String(temp) + "C";  
  String shumid = String(humid) + "%";

  lcd.setCursor(0, 0);               
  lcd.print("Temp: " + stemp);         

  lcd.setCursor(0, 1);                 
  lcd.print("Humidity: " + shumid);    

  sendDataToServer(temp, humid);

  delay(2000); 
}

void connectToWiFi() {
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
}

/*--------------------------------------------------------
Gửi dữ liệu HTTP get request, dữ liệu đóng gói url-encoded
----------------------------------------------------------*/
/*void sendDataToServer(int temp, int humid) {
  if(WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    String url = String(serverUrl);

    http.begin(url);
    http.addHeader("Content-Type", "application/x-www-form-urlencoded");

    int httpCode = http.GET();

    if (httpCode > 0) {
      Serial.print("HTTP GET status code: ");
      Serial.println(httpCode);
    } else {
      Serial.print("HTTP GET request failed, error code: ");
      Serial.println(httpCode);
    }

    http.end();
  } else {
    Serial.println("Error: Not connected to WiFi");
  }
}*/

/*--------------------------------------------------------
Gửi dữ liệu HTTP post request, dữ liệu đóng gói url-encoded
----------------------------------------------------------*/
/*void sendDataToServer(int temp, int humid) {
  if(WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    String url = String(serverUrl);

    http.begin(url);
    http.addHeader("Content-Type", "application/x-www-form-urlencoded");

    String postData = "temperature=" + String(temp) + "&humidity=" + String(humid);

    int httpCode = http.POST(postData);

    if (httpCode > 0) {
      Serial.print("HTTP POST status code: ");
      Serial.println(httpCode);
      

    } else {
      Serial.print("HTTP POST request failed, error code: ");
      Serial.println(httpCode);
    }

    http.end();
  } else {
    Serial.println("Error: Not connected to WiFi");
  }
}*/

/*--------------------------------------------------------
Gửi dữ liệu HTTP post request, dữ liệu đóng gói json (trong request body)
----------------------------------------------------------*/
void sendDataToServer(int temp, int humid) {
  if(WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    String url = String(serverUrl);

    http.begin(url);
    http.addHeader("Content-Type", "application/json");

    String postData = "{\"temperature\": " + String(temp) + ", \"humidity\": " + String(humid) + "}";

    int httpCode = http.POST(postData);

    if (httpCode > 0) {
      Serial.print("HTTP POST status code: ");
      Serial.println(httpCode);
      String response = http.getString();  
      Serial.println("Server Response: ");
      Serial.println(response); 

      
    } else {
      Serial.print("HTTP POST request failed, error code: ");
      Serial.println(httpCode);
    }

    http.end();
  } else {
    Serial.println("Error: Not connected to WiFi");
  }
}