PixelHub/PixelHub-Client/PixelHub-Client.ino

/*
 * Connecting to a WiFi network with WPA
 ************************************************
 * Originally adapted from https://www.arduino.cc/en/Tutorial/ConnectWithWPA
 * by Starbeamrainbowlabs
 */

#include <ESP8266WiFi.h>
#include <WiFiUdp.h>

#include "Utilities.h"

char ssid[] = "evenstar-2.4";
char password[] = "***REMOVED***";

// The address that the PixelHub beacon is broadcasting on.
IPAddress beaconAddress(239, 62, 148, 30);
// The port number that the PixelHub beacon is broadcasting on.
unsigned int beaconPort = 5050;

// A UDP Client to allow us to recieve UDP datagrams.
WiFiUDP UdpClient;
// The size of the datagram buffer that is used to buffer incoming messages.
int datagramBufferSize = 256;

void setup()
{
  // Setup the serial connection
  Serial.begin(4800);

  Serial.println("Hello, world!");
  
  Serial.println("Beginning connection sequence.");
  Serial.print("Attempting to connect to ");
  Serial.print(ssid);
  Serial.print(" - ");
  
  WiFi.begin(ssid, password);
  
  while(WiFi.status() != WL_CONNECTED)
  {


    //  Wait 10 seconds for the connection to start
    delay(10000);
  }
  
  Serial.println("success!");

  printWiFiInfoLocal();
  findServer();
}

void loop()
{
  
}

void printWiFiInfoLocal()
{
  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP());
}

void findServer()
{
  Serial.print("Initialising PixelHub auto detection system - ");
  byte datagramBuffer[datagramBufferSize];
  UdpClient.beginMulticast(WiFi.localIP(), beaconAddress, beaconPort);
  Serial.println("success!");

  Serial.println("Listening for PixelHub beacon pings.");
  while(true) {
    int datagramSize = UdpClient.parsePacket();
    if(!datagramSize) continue;
    
    Serial.print("Received datagram #");
    Serial.print(datagramSize);
    Serial.print(" bytes in size from ");
    Serial.print(UdpClient.remoteIP());
    Serial.print(":");
    Serial.print(UdpClient.remotePort());
    if(datagramSize > datagramBufferSize) {
      Serial.println(", but the message is larger than the datagram buffer size.");
      continue;
    }
    Serial.println(".");
    
    UdpClient.read(datagramBuffer, datagramSize);
    
    Serial.print("Content as hex: ");
    for(int i = 0; i < datagramSize; i++) {
      Serial.print(datagramBuffer[i], HEX);
      Serial.print(" ");
    }
    Serial.println();
    Serial.print("Raw content: ");
    Serial.write(datagramBuffer, datagramSize);
    Serial.println();

    Serial.print("Parsing datagram - ");

    // Parse the recieved message
    char* datagramStr = (char*)datagramBuffer;

    // Find the positions of the key characters
    int atPos = findChar(datagramStr, '@');
    int colonPos = findChar(datagramStr, ':');

    char* role;
    char* serverIp;
    char* portNumberText;

    strncpy(role, datagramStr, atPos);
    strncpy(serverIp, datagramStr + atPos + 1, colonPos);
    strncpy(portNumberText, datagramStr + colonPos + 1, datagramSize - 1);

    Serial.println("complete.");
    
    Serial.print("Role: "); Serial.print(role); Serial.print(" ");
    Serial.print("Remote IP: "); Serial.print(serverIp); Serial.print(" ");
    Serial.print("Port number: "); Serial.print(portNumberText);
    Serial.println();
    
    // If the advertiser isn't playing the role of a server, then we're not interested
    if(role != "server") continue;

    int portNumber = atoi(portNumberText);
  }
}