/*

 ThingSpeak Client to Update Channel Feeds

 The ThingSpeak Client sketch is designed for the Arduino + Ethernet Shield.
 This sketch updates a channel feed with an analog input reading via the
 ThingSpeak API (http://community.thingspeak.com/documentation/)
 using HTTP POST.

 Getting Started with ThingSpeak:

    * Sign Up for New User Account - https://www.thingspeak.com/users/new
    * Create a New Channel by selecting Channels and then Create New Channel
    * Enter the Write API Key in this sketch under "ThingSpeak Settings"

 Created: January 25, 2011 by Hans Scharler (http://www.iamshadowlord.com)

 Additional Credits: Example sketches from Tom Igoe and David A. Mellis

*/

#include <SPI.h>
#include <Ethernet.h>

 int sensorPin = 0;



// Local Network Settings
byte mac[]     = { 0xD4, 0x28, 0xB2, 0xFF, 0xA0, 0xA1 }; // Must be unique on local network
byte ip[]      = { 192, 168, 1, 140 };                // Must be unique on local network
byte gateway[] = { 192, 168, 1, 1 };
byte subnet[]  = { 255, 255, 255, 0 };

// ThingSpeak Settings
byte server[]  = { 184, 106, 153, 149 }; // IP Address for the ThingSpeak API
String writeAPIKey = "xxxxxxxxxxxxxx";    // Write API Key for a ThingSpeak Channel
const int updateInterval = 10000;        // Time interval in milliseconds to update ThingSpeak
Client client(server, 80);

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

void setup()
{
  Ethernet.begin(mac, ip, gateway, subnet);
  Serial.begin(9600);
  delay(1000);
  int reading = analogRead(sensorPin);
  float voltage = reading * 5.0;
  voltage /= 1024.0;
  int temperatureC = (voltage) * 100 ;
}

void loop()
{
  int reading = analogRead(sensorPin);
  float voltage = reading * 5.0;
  voltage /= 1024.0;
  long temperatureC = (voltage) * 100;

String temper = String(temperatureC, DEC);
  /*
  /Serial.print(temperatureC);
  delay (1000);
  */


  // Print Update Response to Serial Monitor
  if (client.available())
  {
    char c = client.read();
    Serial.print(c);
  }

  // Disconnect from ThingSpeak
  if (!client.connected() && lastConnected)
  {
    Serial.println();
    Serial.println("...disconnected.");
    Serial.println();

    client.stop();
  }

  // Update ThingSpeak
  if(!client.connected() && (millis() - lastConnectionTime > updateInterval))
  {
    //updateThingSpeak("field1="+(temperatureC, DEC));
    updateThingSpeak("field1="+temper);
     //updateThingSpeak("field1="+(temper, DEC));
  }

  lastConnected = client.connected();
}

void updateThingSpeak(String tsData)
{
  if (client.connect())
  {
    Serial.println("Connected to ThingSpeak...");
    Serial.println();

    client.print("POST /update HTTP/1.1\n");
    client.print("Host: api.thingspeak.com\n");
    client.print("Connection: close\n");
    client.print("X-THINGSPEAKAPIKEY: "+writeAPIKey+"\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();

    resetCounter = 0;

  }
  else
  {
    Serial.println("Connection Failed.");
    Serial.println();

    resetCounter++;

    if (resetCounter >=5 ) {resetEthernetShield();}

    lastConnectionTime = millis();
  }
}

void resetEthernetShield()
{
  Serial.println("Resetting Ethernet Shield.");
  Serial.println();

  client.stop();
  delay(1000);

  Ethernet.begin(mac, ip, gateway, subnet);
  delay(1000);
}