#include <ModbusMaster.h>
ModbusMaster node;
static uint8_t pzemSlaveAddr = 1;

float voltage,  current, power, energy, freq, pf;
#define pzemSerial Serial2


#define TINY_GSM_MODEM_SIM800      // Modem is SIM800
#include <TinyGsmClient.h>


// Your GPRS credentials (leave empty, if not needed)
const char apn[]  = "Internet";
const char user[] = "";
const char Pass[] = "";

// The server variable can be just a domain name or it can have a subdomain. It depends on the service you are using
const char server[] = "thingspeak.com"; // domain name: example.com, maker.ifttt.com, etc
const char resource[] = "https://api.thingspeak.com/update?api_key=QPH1MMAE2486DIG2";
const int  port = 80;                   // server port number
String apiKey = "QPH1MMAE2486DIG2";

// Set serial for AT commands (to SIM800 module)
#define SerialAT Serial1
TinyGsm modem(SerialAT);

// TinyGSM Client for Internet connection
TinyGsmClient client(modem, 0);

#define MODEM_TX             25
#define MODEM_RX             26

// Set serial for PZEM
#define RXD1 16
#define TXD1 17
#define PKEY 14

//Untuk watchdog external
#define  wdtPin  15
#define  ledPin  19
bool wdtState = 0;
unsigned cur_time_push, old_time_push;
unsigned cur_time_wdt, old_time_wdt;
unsigned cur_time_rst, old_time_rst;
/*
  RegAddr Description                 Resolution
  0x0000  Voltage value               1LSB correspond to 0.1V
  0x0001  Current value low 16 bits   1LSB correspond to 0.001A
  0x0002  Current value high 16 bits
  0x0003  Power value low 16 bits     1LSB correspond to 0.1W
  0x0004  Power value high 16 bits
  0x0005  Energy value low 16 bits    1LSB correspond to 1Wh
  0x0006  Energy value high 16 bits
  0x0007  Frequency value             1LSB correspond to 0.1Hz
  0x0008  Power factor value          1LSB correspond to 0.01
  0x0009  Alarm status  0xFFFF is alarm，0x0000is not alarm
*/

void setup() {
  pinMode(wdtPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  pzemSerial.begin(9600);
  Serial.begin(115200);
  // Set GSM module baud rate and UART pins
  Serial2.begin(9600, SERIAL_8N1, RXD1, TXD1);//pzem 16
  SerialAT.begin(9600, SERIAL_8N1, MODEM_RX, MODEM_TX);//gsm
  node.begin(pzemSlaveAddr, pzemSerial);
  Serial.println("Initializing modem...");
  modem.restart();
  Serial.print("Connecting to APN: ");
  Serial.print(apn);
  if (!modem.gprsConnect(apn, user, Pass)) {
    Serial.println(" fail");
  }
  else {
    Serial.println("OK");
  }
}

void loop() {
  cur_time_wdt = millis();
  if (cur_time_wdt - old_time_wdt > 250) {
    wdtSeed();
    old_time_wdt = millis();
  }

  cur_time_rst = millis() / 1000;
  if (cur_time_rst - old_time_rst >= 3600) {
    ESP.restart();
  }

  cur_time_push = millis();
  if (cur_time_push - old_time_push > 1500) {
    pushServer();
    old_time_push = millis();
  }

}

void pushServer() {
  uint8_t result;
  result = node.readInputRegisters(0, 9); //read the 9 registers of the PZEM-014 / 016
  if (result == node.ku8MBSuccess)
  {
    Serial.println("sukses modbus");
    voltage = node.getResponseBuffer(0) / 10.0;

    uint32_t tempdouble = 0x00000000;

    tempdouble = node.getResponseBuffer(1);       //LowByte
    tempdouble |= node.getResponseBuffer(2) << 8;  //highByte
    current = tempdouble / 1000.0;

    tempdouble |= node.getResponseBuffer(3);       //LowByte
    tempdouble |= node.getResponseBuffer(4) << 8;  //highByte
    power = tempdouble / 10.0;

    tempdouble = node.getResponseBuffer(5);       //LowByte
    tempdouble |= node.getResponseBuffer(6) << 8;  //highByte
    energy = tempdouble;

    tempdouble = node.getResponseBuffer(7);
    freq = tempdouble / 10.0;

    tempdouble = node.getResponseBuffer(8);
    pf = tempdouble / 10.0;

    //SEND TO THINKSPEAK

    Serial.print("Connecting to ");
    Serial.print(server);
    if (!client.connect(server, port)) {
      Serial.println(" fail");
    }
    else {
      Serial.println(" OK");

      // Making an HTTP POST request
      Serial.println("Performing HTTP POST request...");
      // Prepare your HTTP POST request data (Temperature in Celsius degrees)
      Serial.println("Performing HTTP POST request...");
      // Prepare your HTTP POST request data (Temperature in Celsius degrees)


      String httpRequestData = "api_key=" + apiKey + "&field1=" + String(voltage) + "&field2=" + String(current) + "&field3=" + String(freq) + "&field4=" + String(power) + "&field5=" + String(energy) + "&field6=" + String(pf) + "";

      client.print(String("POST ") + resource + " HTTP/1.1\r\n");
      client.print(String("Host: ") + server + "\r\n");
      client.println("Connection: close");
      client.println("Content-Type: application/x-www-form-urlencoded");
      client.print("Content-Length: ");
      client.println(httpRequestData.length());
      client.println();
      client.println(httpRequestData);


      unsigned long timeout = millis();
      while (client.connected() && millis() - timeout < 10000L) {
        // Print available data (HTTP response from server)
        while (client.available()) {
          char c = client.read();
          Serial.print(c);
          timeout = millis();
        }
      }
    }
    Serial.println();

    // Close client and disconnect
    client.stop();
    //      Serial.println(F("Server disconnected"));
    //      modem.gprsDisconnect();
    //      Serial.println(F("GPRS disconnected"));
  }
}

void wdtSeed() {
  wdtState = !wdtState;
  digitalWrite(wdtPin, wdtState);
  digitalWrite(ledPin, wdtState);
}