#include "WiFi.h"
#include <PubSubClient.h>
#include <ArduinoJson.h>
#include <time.h>

unsigned long lastTransmissionTime = 0;
boolean transmissionFlag = 1;

const char* mqtt_server = "broker.emqx.io";
const char* mqtt_topic = "/thing";
const int mqtt_port = 1883;
const char* username = "ritesh";
const char* password = "ritesh";
const char* clientId = "randomwords";

int count = 0; //To find the number of mqtt requests sent

// NTP Server settings
// const char *ntp_server = "pool.ntp.org";     // Default NTP server
// const char* ntp_server = "cn.pool.ntp.org"; // Recommended NTP server for users in China
// const long gmt_offset_sec = 0;            // GMT offset in seconds (adjust for your time zone)
// const int daylight_offset_sec = 0;        // Daylight saving time offset in seconds

// WiFi and MQTT client initialization
// BearSSL::WiFiClientSecure espClient;
WiFiClient espClient;
PubSubClient mqttClient(espClient);

// SSL certificate for MQTT broker
// Load DigiCert Global Root CA ca_cert, which is used by EMQX Cloud Serverless Deployment

// static const char ca_cert[] PROGMEM = R"EOF(
// -----BEGIN CERTIFICATE-----
// MIIDrzCCApegAwIBAgIQCDvgVpBCRrGhdWrJWZHHSjANBgkqhkiG9w0BAQUFADBh
// MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
// d3cuZGlnaWNlcnQuY29tMSAwHgYDVQQDExdEaWdpQ2VydCBHbG9iYWwgUm9vdCBD
// QTAeFw0wNjExMTAwMDAwMDBaFw0zMTExMTAwMDAwMDBaMGExCzAJBgNVBAYTAlVT
// MRUwEwYDVQQKEwxEaWdpQ2VydCBJbmMxGTAXBgNVBAsTEHd3dy5kaWdpY2VydC5j
// b20xIDAeBgNVBAMTF0RpZ2lDZXJ0IEdsb2JhbCBSb290IENBMIIBIjANBgkqhkiG
// 9w0BAQEFAAOCAQ8AMIIBCgKCAQEA4jvhEXLeqKTTo1eqUKKPC3eQyaKl7hLOllsB
// CSDMAZOnTjC3U/dDxGkAV53ijSLdhwZAAIEJzs4bg7/fzTtxRuLWZscFs3YnFo97
// nh6Vfe63SKMI2tavegw5BmV/Sl0fvBf4q77uKNd0f3p4mVmFaG5cIzJLv07A6Fpt
// 43C/dxC//AH2hdmoRBBYMql1GNXRor5H4idq9Joz+EkIYIvUX7Q6hL+hqkpMfT7P
// T19sdl6gSzeRntwi5m3OFBqOasv+zbMUZBfHWymeMr/y7vrTC0LUq7dBMtoM1O/4
// gdW7jVg/tRvoSSiicNoxBN33shbyTApOB6jtSj1etX+jkMOvJwIDAQABo2MwYTAO
// BgNVHQ8BAf8EBAMCAYYwDwYDVR0TAQH/BAUwAwEB/zAdBgNVHQ4EFgQUA95QNVbR
// TLtm8KPiGxvDl7I90VUwHwYDVR0jBBgwFoAUA95QNVbRTLtm8KPiGxvDl7I90VUw
// DQYJKoZIhvcNAQEFBQADggEBAMucN6pIExIK+t1EnE9SsPTfrgT1eXkIoyQY/Esr
// hMAtudXH/vTBH1jLuG2cenTnmCmrEbXjcKChzUyImZOMkXDiqw8cvpOp/2PV5Adg
// 06O/nVsJ8dWO41P0jmP6P6fbtGbfYmbW0W5BjfIttep3Sp+dWOIrWcBAI+0tKIJF
// PnlUkiaY4IBIqDfv8NZ5YBberOgOzW6sRBc4L0na4UU+Krk2U886UAb3LujEV0ls
// YSEY1QSteDwsOoBrp+uvFRTp2InBuThs4pFsiv9kuXclVzDAGySj4dzp30d8tbQk
// CAUw7C29C79Fv1C5qfPrmAESrciIxpg0X40KPMbp1ZWVbd4=
// -----END CERTIFICATE-----
// )EOF";


void setup() {
  Serial.begin(115200);
  WiFi.disconnect();  //Disconnect from previously connected wifi
  Serial.println("\nWifi disconnected");

  delay(200);

  WiFi.mode(WIFI_STA);  //STAtion mode: the ESP8266 connects to an access point

  // syncTime();

  mqttClient.setServer(mqtt_server, mqtt_port);
}

void loop() {
  connectWifi();
  mqttClient.loop();
  getData();


  delay(2000); // Wait for a new reading from the sensor (DHT22 has ~0.5Hz sample rate)
}

void connectWifi() {
  if (WiFi.status() != WL_CONNECTED) {
    Serial.println("Attempting to connect to WiFi");
    WiFi.begin("Wokwi-GUEST", "");
    while (WiFi.status() != WL_CONNECTED) {
      Serial.println(".");
      delay(1000);
    }
    Serial.println("Wifi Connected");
    return;
  }
}

// void syncTime() {
  // configTime(gmt_offset_sec, daylight_offset_sec, ntp_server);
  // Serial.print("Waiting for NTP time sync: ");
  // while (time(nullptr) < 8 * 3600 * 2) {
  //   delay(1000);
  //   Serial.print(".");
  // }
  // Serial.println("Time synchronized");
  // struct tm timeinfo;
  // if (getLocalTime(&timeinfo)) {
  //   Serial.print("Current time: ");
  //   Serial.println(asctime(&timeinfo));
  // } else {
  //   Serial.println("Failed to obtain local time");
  // }
// }

void getData() {

  double randomDecimal = random(0, 100) / 100.0;
  double temp = random(0, 100) + randomDecimal;
  double humidity = random(0, 100) + randomDecimal;
  Serial.println("----------------");
  Serial.print("Humidity: " + String(humidity) + "% , ");
  Serial.println("Temp: " + String(temp) + "°C");

  unsigned long currentTime = millis();
  int time_elapsed = currentTime - lastTransmissionTime;
  Serial.println("Time elapsed: " + String(time_elapsed));

  StaticJsonDocument<50> doc;
  doc["Humidity"] = humidity;
  doc["Temperature"] = temp;

  // Serialize the JSON object to a string
  String jsonString;
  serializeJson(doc, jsonString);

  // if ((time_elapsed >= 6000) && transmissionFlag) {
  connectMQTT(jsonString);
  lastTransmissionTime = currentTime;
  // }
}

void connectMQTT(String jsonString) {
  int retryCount = 4;
  // BearSSL::X509List serverTrustedCA(ca_cert);
  // espClient.setTrustAnchors(&serverTrustedCA);
  while (!mqttClient.connected() && retryCount) {
    Serial.print("Attempting MQTT connection...");
    if (mqttClient.connect(clientId,username,password)) {
      Serial.println("connected " + String(count++));
      mqttClient.publish(mqtt_topic, jsonString.c_str());
      // count++;
    } else {

      Serial.print("failed, rc=");
      Serial.print(mqttClient.state());
      Serial.println(" try again in 2 seconds");
      delay(2000);
      retryCount--;
    }
  }
  mqttClient.disconnect();
}