/*

WiFi 101 ThingSpeak Data Uploader

Hardware Required:

* Arduino Zero or Uno Board

* Arduino Wifi Shield 101

* Photocell

* Temperature Sensor (This example uses a TMP36)

* 10K Ohm Resistor

created Sept 2015

by Helena Bisby <[email protected]>

This example code is in the public domain

http://arduino.cchttps://www.arduino.cc/en/Tutorial/WiFi101ThingSpeakDataUploader

*/
#include <string.h> //Biblioteka za rad sa string-ovima, koristi se za strcmp funkcijum

///////please enter your sensitive data in the Secret tab/arduino_secrets.h
char ssid[] = "Wokwi-GUEST";     // your network SSID (name)
char pass[] = "";    // your network password (use for WPA, or use as key for WEP)
int keyIndex = 0;             // your network key Index number (needed only for WEP)

String SendATCmdAndGetResponse(String str)
{
  Serial1.println(str);

  String response = "";

  if(Serial1.available() > 0)
  {
    response = Serial1.readString();
  }

  return response;
}

// ThingSpeak Settings
char thingSpeakAddress[] = "api.thingspeak.com";

String APIKey = "1G4LCJ8KFWS2UDGD";             // enter your channel's Write API Key

const int updateThingSpeakInterval = 20 * 1000; // 20 second interval at which to update ThingSpeak

// Variable Setup
long lastConnectionTime = 0;
boolean lastConnected = false;

// Initialize Arduino Ethernet Client

//WiFiClient client;

void setup() {

  // Start Serial for debugging on the Serial Monitor

  Serial.begin(9600);
  Serial1.begin(9600); //Serial for at command

  Serial.println("Connecting with WiFi 'Wokwi-GUEST'...");
  Serial.print(SendATCmdAndGetResponse("AT+CWJAP=\"Wokwi-GUEST\",")); //connect to wifi

  printWifiStatus();
}

void loop() {

  // read values from pins and store as strings

  String light = String(analogRead(A0), DEC); // read light value

  // find temp value

  float voltage = analogRead(A1) * (3.3 / 1024);  // convert 0-1023 range to 3.3V range

  int tempVal = (voltage - 0.5) * 100;            // convert voltage to temperature in *C

  String temp = String(tempVal);

  // Disconnect from ThingSpeak

  if (strchr(SendATCmdAndGetResponse("AT+CWSTATE?"), '2') != NULL && lastConnected) {

    Serial.println("...disconnected");

    Serial.println(SendATCmdAndGetResponse("AT+CWQAP"));   

  }

  // Update ThingSpeak

  if (strchr(SendATCmdAndGetResponse("AT+CWSTATE?"), '2') != NULL && (millis() - lastConnectionTime > updateThingSpeakInterval)) {

    updateThingSpeak("\"field1: " + light + "\",\"field2: " + temp + "\"");

    Serial.println(light);

    Serial.println(temp);

  }

  lastConnected = strchr(SendATCmdAndGetResponse("AT+CWSTATE?"), '2') != NULL;
}

void updateThingSpeak(String tsData) {

  String httpCommand = "AT+HTTPCPOST=\"https://api.thingspeak.com/update.json\",5\
  [\"Host: api.thingspeak.com\",\"Connection: close\",\"Content-Type: application/x-www-form-urlencoded\",\
  \"api_key: " + APIKey + "\",\
  \"Content-Type: application/x-www-form-urlencoded\"," + tsData + "\",\"channel_id:1724077\"]";

  Serial.println("--SENDING TO THINKSPEAK--");

  Serial.println(httpCommand);

  Serial.println("--STATUS--");

  Serial.println(SendATCmdAndGetResponse(httpCommand));
/*

  if (client.connect(thingSpeakAddress, 80)) {

    client.print("Host: api.thingspeak.com\n");

    client.print("Connection: close\n");

    client.print("X-THINGSPEAKAPIKEY: " + APIKey + "\n");

    client.print("Content-Type: application/x-www-form-urlencoded\n");

    client.print("Content-Length: ");

    client.print(tsData.length());

    client.print("\n\n");

    client.print(tsData);

    lastConnectionTime = millis();

    if (client.connected()) {

      Serial.println("Connecting to ThingSpeak...");

      Serial.println();

    }

  }*/
}

void printWifiStatus() {

  String cwState = SendATCmdAndGetResponse("AT+CWSTATE?");

  if(strchr(cwState, '2') != NULL){
    Serial.print("SSID: ");
    Serial.println( (cwState.split(',')[1]).split(' ')[0] );
  } else {
    Serial.println(cwState);
  }

  String cwLif = SendATCmdAndGetResponse("AT+CWLIF");

  Serial.print("IP Address: ");

  Serial.println((cwLif.split(':')[1]).split(',')[0]);


  String cwLap = SendATCmdAndGetResponse("AT+CWLAP");

  Serial.print("Ostali podaci o WiFi signalu: ");

  Serial.println(cwLap);
}