/*************************************************************************************************
                                      PROGRAMMINFO
**************************************************************************************************
Funktion: ESP32 Wetterdaten OLED-Display 1.3"
**************************************************************************************************

Server-Abfrage:
http://api.weatherstack.com/current?access_key=c161b8689410c8488ff843ae06af29e7&query=Tegernsee

**************************************************************************************************
Version: 07.07.2021
**************************************************************************************************
Board: ESP32vn IoT UNO V1.0.4
**************************************************************************************************
C++ Arduino IDE V1.8.13
**************************************************************************************************
Einstellungen:
https://dl.espressif.com/dl/package_esp32_index.json
http://dan.drown.org/stm32duino/package_STM32duino_index.json
https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_dev_index.json
 **************************************************************************************************/

#include <WiFi.h>
#include <HTTPClient.h>
#include <Arduino_JSON.h>

const char* ssid = "xxx";
const char* password = "xxx";

String openWeatherMapApiKey = "Hier deine API eintragen";
String city = "Tegernsee";
String countryCode = "DE";

unsigned long lastTime = 0;
// Timer set to 10 Minuten (600000)
//unsigned long timerDelay = 600000;
// Set timer to 10 Sekunden (10000)
unsigned long timerDelay = 10000;

String jsonBuffer;


//-----------------------------------------------
#include <Arduino.h>
#include <U8g2lib.h>

#ifdef U8X8_HAVE_HW_SPI
#include <SPI.h>
#endif
#ifdef U8X8_HAVE_HW_I2C
#include <Wire.h>
#endif

U8G2_SH1106_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0, /* reset=*/ U8X8_PIN_NONE);
unsigned long delayTime;
//-----------------------------------------------


void setup() {
  Serial.begin(115200);

  WiFi.begin(ssid, password);
  Serial.println("Verbinde");
  while(WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("Verbunden mit IP Addresse: ");
  Serial.println(WiFi.localIP());

  Serial.println("Aktualisierung ist auf 10 Sekunden eingestellt.");
//-----------------------------------------------

    u8g2.begin();
//-----------------------------------------------

}

void loop() {
  if ((millis() - lastTime) > timerDelay) {
    // Check WiFi Status
    if(WiFi.status()== WL_CONNECTED){
      String serverPath = "http://api.weatherstack.com/current?access_key=c161b8689410c8488ff843ae06af29e7&query=Tegernsee";

      jsonBuffer = httpGETRequest(serverPath.c_str());
      Serial.println(jsonBuffer);
      JSONVar myObject = JSON.parse(jsonBuffer);

        if (JSON.typeof(myObject) == "undefined") {
        Serial.println("Eingabe fehlgeschlagen!");
        return;
      }
     Serial.print("JSON object = ");

      Serial.println("Meine Wetterdaten:");

      Serial.print("Ort: ");
      Serial.println(myObject["location"]["name"]);

      Serial.print("Aktuelle Temperatur: ");
      Serial.print(myObject["current"]["temperature"]);
      Serial.println("°C");

      Serial.print("Luftdruck: ");
      Serial.print(myObject["current"]["pressure"]);
      Serial.println("hPa");

      Serial.print("Luftfeuchte: ");
      Serial.print(myObject["current"]["humidity"]);
      Serial.println("%");

      Serial.print("Bewölkung: ");
      Serial.print(myObject["current"]["cloudcover"]);
      Serial.println("%");

      Serial.print("Windrichtung: ");
      Serial.println(myObject["current"]["wind_dir"]);

//---------------------------------------------------------

Serial.println("=================================");

    u8g2.setFont(u8g2_font_courR10_tf);
    u8g2.firstPage();

    do {

      u8g2.setCursor(12, 9);
      u8g2.print("Wetterdaten");
      u8g2.setCursor(18, 22);
      u8g2.print("Tegernsee");

      u8g2.setCursor(2, 35);
      u8g2.print("Temp: ");
      u8g2.setCursor(51, 35);
      u8g2.print(myObject["current"]["temperature"]);
      u8g2.print("\xB0""C");

      u8g2.setCursor(2, 48);
      u8g2.print("Wind:");
      u8g2.setCursor(51, 48);
      u8g2.print(myObject["current"]["wind_speed"]);
      u8g2.print("m/s");
/*
      u8g2.setCursor(2, 48);
      u8g2.print("LuFe:");
      u8g2.setCursor(51, 48);
      u8g2.print(myObject["main"]["humidity"]);
      u8g2.print("%");
*/


      u8g2.setCursor(2, 63);
      u8g2.print("LuDr:");
      u8g2.setCursor(51, 63);
      u8g2.print(myObject["current"]["pressure"]);
      u8g2.print("hPa");

      } while ( u8g2.nextPage() );
     delay(delayTime);
//---------------------------------------------------------

   }

    else {
      Serial.println("WiFi Disconnected");
    }
    lastTime = millis();
  }
}

String httpGETRequest(const char* serverName) {
  WiFiClient client;
  HTTPClient http;

  // Domain-Name
  http.begin(client, serverName);

  // HTTP POST request 200=OK
  int httpResponseCode = http.GET();

  String payload = "{}";

  if (httpResponseCode>0) {
    Serial.print("HTTP-Antwort Code (200=OK): ");
    Serial.println(httpResponseCode);
    Serial.println("Server-Meldung: ");
    payload = http.getString();
  }
  else {
    Serial.print("Error code: ");
    Serial.println(httpResponseCode);
  }

  http.end();

  return payload;
}