/* ******************************************************
 * WebServer_XbeeComm_POST.ino
 * ****************************************************** */
 #include <SPI.h>
 #include <Ethernet.h>
 
 byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
 byte ip[] =  { 192, 168, 11, 81 };
 EthernetServer server(80);
 
 const int MAX_PAGENAME_LEN = 8;  // max characters in page name 
 char buffer[MAX_PAGENAME_LEN+1]; // additional character for terminating null
 
 void setup()
 {
      Serial.begin(9600);
      
      Ethernet.begin(mac, ip);
      server.begin();
      delay(2000);
 }
 
 void loop()
 {
      char inChar;
      
      EthernetClient client = server.available();
      if (client) {
         while (client.connected()) {
               if (client.available()) {
                  // Parsing HTTP Request to extract NXT command:
                  // >> POST / HTTP/1.1
                  // >> body of http header
                  // >> \n\r
                  // >> ledEffect=K or F or H
                  memset(buffer,0, sizeof(buffer));
                  if (client.readBytesUntil('/', buffer,sizeof(buffer))) { 
                     if (strcmp(buffer,"POST ") == 0) {
                        client.find("\n\r"); // Skip body of http header
                        if (client.findUntil("ledEffect", "\n\r")) {
                           client.read();           // Read '='
                           inChar = client.read();  // Read 'K','F','H'
                           if (inChar == 'K') sendCommand("  K@");
                           else
                           if (inChar == 'F') sendCommand("  F@");
                           else
                           if (inChar == 'H') sendCommand("  H@");
                        }
                     }
                     // Send back HTTP Response to Client
                     sendHeader(client,"Magicwand LED Effects");                      
                     client.print(  "<h2 style='text-align: center; background-color: blue; color: white;'>");
                     client.println("Click Buttons To Show LED Effects on NXT</h2><br>");
                      
                     client.print(  "<form action='/' method='POST'><p><input type='hidden' name='ledEffect' value='K'>");
                     client.println("<input type='submit' value='KnightRider' style='height: 1.2em; width: 6.5em; font-size: 800%;'/></p></form><br>");
                      
                     client.print(  "<form action='/' method='POST'><p><input type='hidden' name='ledEffect' value='F'>");
                     client.println("<input type='submit' value='Fireworks'   style='height: 1.2em; width: 6.5em; font-size: 800%;'/></p></form><br>");
                      
                     client.print(  "<form action='/' method='POST'><p><input type='hidden' name='ledEffect' value='H'>");
                     client.println("<input type='submit' value='HeartBeats'  style='height: 1.2em; width: 6.5em; font-size: 800%;'/></p></form>");
                      
                     client.println("</body></html>");
                     client.stop();
                  } // if (client.readBytesUntil('/', buffer,sizeof(buffer)))
               } // if (client.available())
         } // while (client.connected())
         delay(1);
         client.stop();
      } // if (client)
 }
/* ******************************************************
 * Sends command then waitting for incoming ACK message
 * ****************************************************** */ 
 boolean sendCommand(String outString)
 { 
      char       inChar;
      boolean    statusReturn  = false;   
      const long waitTimeLimit = 5000;
      long       startTimeMillis;
   
      //flashLED(1);
      Serial.print(outString);
   
      startTimeMillis = millis();
      while((millis() - startTimeMillis) < waitTimeLimit) {   
           inChar = ' ';
           if (Serial.available() > 0) {
              inChar = (char) Serial.read();
              if (inChar == '@') {
                 statusReturn = true;
                 break;
              }
           }  
      }
      return statusReturn;  
 }
 void sendHeader(EthernetClient client, char *title)
 {
      // send a standard http response header
      client.println("HTTP/1.1 200 OK");
      client.println("Content-Type: text/html");
      client.println();
      client.print("<html><head><title>");
      client.print(title);
      client.println("</title></head><body>");
 }