/**************************************************************
 *
 * This sketch connects to a website and downloads a page.
 * It can be used to perform HTTP/RESTful API calls.
 *
 * For this example, you need to install ArduinoHttpClient library:
 *   https://github.com/arduino-libraries/ArduinoHttpClient
 *   or from http://librarymanager/all#ArduinoHttpClient
 *
 * TinyGSM Getting Started guide:
 *   https://tiny.cc/tinygsm-readme
 *
 * SSL/TLS is currently supported only with: SIM8xx, uBlox, ESP8266
 *
 * For more HTTP API examples, see ArduinoHttpClient library
 *
 **************************************************************/

// Select your modem:
#define TINY_GSM_MODEM_SIM800
// #define TINY_GSM_MODEM_SIM808
// #define TINY_GSM_MODEM_SIM868
// #define TINY_GSM_MODEM_UBLOX
// #define TINY_GSM_MODEM_SARAR4
// #define TINY_GSM_MODEM_ESP8266

// Increase RX buffer to capture the entire response
// Chips without internal buffering (ESP8266)
// need enough space in the buffer for the entire response
// else data will be lost (and the http library will fail).
#define TINY_GSM_RX_BUFFER 650

// See the debugging, if wanted
//#define TINY_GSM_DEBUG Serial
//#define LOGGING

// Add a reception delay, if needed
//#define TINY_GSM_YIELD() { delay(1); }

#include <TinyGsmClient.h>
#include <ArduinoHttpClient.h>

// Uncomment this if you want to see all AT commands
//#define DUMP_AT_COMMANDS

// Set serial for debug console (to the Serial Monitor, default speed 115200)
#define SerialMon Serial

// Use Hardware Serial on Mega, Leonardo, Micro
#define SerialAT Serial1

// or Software Serial on Uno, Nano
//#include <SoftwareSerial.h>
//SoftwareSerial SerialAT(2, 3); // RX, TX


// Your GPRS credentials
// Leave empty, if missing user or pass
const char apn[]  = "YourAPN";
const char gprsUser[] = "";
const char gprsPass[] = "";
const char wifiSSID[]  = "YourSSID";
const char wifiPass[] = "SSIDpw";

// Server details
const char server[] = "vsh.pp.ua";
const char resource[] = "/TinyGSM/logo.txt";
const int  port = 443;

#ifdef DUMP_AT_COMMANDS
  #include <StreamDebugger.h>
  StreamDebugger debugger(SerialAT, SerialMon);
  TinyGsm modem(debugger);
#else
  TinyGsm modem(SerialAT);
#endif

TinyGsmClientSecure client(modem);
HttpClient http(client, server, port);

void setup() {
  // Set console baud rate
  SerialMon.begin(115200);
  delay(10);
  SerialMon.println(F("Wait..."));

  // Set GSM module baud rate
  SerialAT.begin(115200);
  delay(3000);

  // Restart takes quite some time
  // To skip it, call init() instead of restart()
  SerialMon.println(F("Initializing modem..."));
  modem.restart();

  String modemInfo = modem.getModemInfo();
  SerialMon.print(F("Modem: "));
  SerialMon.println(modemInfo);

  // Unlock your SIM card with a PIN
  //modem.simUnlock("1234");

  if (!modem.hasSSL()) {
    SerialMon.println(F("SSL is not supported by this modem"));
    while(true) { delay(1000); }
  }
}

void loop() {

  if (modem.hasWifi()) {
    SerialMon.print(F("Setting SSID/password..."));
    if (!modem.networkConnect(wifiSSID, wifiPass)) {
      SerialMon.println(" fail");
      delay(10000);
      return;
    }
    SerialMon.println(" OK");
  }

  SerialMon.print(F("Waiting for network..."));
  if (!modem.waitForNetwork()) {
    SerialMon.println(" fail");
    delay(10000);
    return;
  }
  SerialMon.println(" OK");

  if (modem.hasGPRS()) {
    SerialMon.print(F("Connecting to "));
    SerialMon.print(apn);
    if (!modem.gprsConnect(apn, gprsUser, gprsPass)) {
      SerialMon.println(" fail");
      delay(10000);
      return;
    }
    SerialMon.println(" OK");
  }

  SerialMon.print(F("Performing HTTPS GET request... "));
  http.connectionKeepAlive(); // Currently, this is needed for HTTPS
  int err = http.get(resource);
  if (err != 0) {
    SerialMon.println(F("failed to connect"));
    delay(10000);
    return;
  }

  int status = http.responseStatusCode();
  SerialMon.print(F("Response status code: "));
  SerialMon.println(status);
  if (!status) {
    delay(10000);
    return;
  }

  SerialMon.println(F("Response Headers:"));
  while (http.headerAvailable()) {
    String headerName = http.readHeaderName();
    String headerValue = http.readHeaderValue();
    SerialMon.println("    " + headerName + " : " + headerValue);
  }

  int length = http.contentLength();
  if (length >= 0) {
    SerialMon.print(F("Content length is: "));
    SerialMon.println(length);
  }
  if (http.isResponseChunked()) {
    SerialMon.println(F("The response is chunked"));
  }

  String body = http.responseBody();
  SerialMon.println(F("Response:"));
  SerialMon.println(body);

  SerialMon.print(F("Body length is: "));
  SerialMon.println(body.length());

  // Shutdown

  http.stop();
  SerialMon.println(F("Server disconnected"));

  modem.gprsDisconnect();
  SerialMon.println(F("GPRS disconnected"));

  // Do nothing forevermore
  while (true) {
    delay(1000);
  }
}