#include <EtherCard.h>

static byte mymac[] = { 0xD0,0x37,0x72,0x9B,0x3F,0x9E  };
static byte myip[] = { 192,168,0,190 };

#define BUFFER_SIZE   500
byte Ethernet::buffer[BUFFER_SIZE];
BufferFiller bfill;

#define CS_PIN       10

#define RELAIS_1     2
#define RELAIS_2     3
#define RELAIS_3     4
bool relais1Status = false;
bool relais2Status = false;
bool relais3Status = false;

const char http_OK[] PROGMEM =
"HTTP/1.0 200 OK\r\n"
"Content-Type: text/html\r\n"
"Pragma: no-cache\r\n\r\n";

const char http_Found[] PROGMEM =
"HTTP/1.0 302 Found\r\n"
"Location: /\r\n\r\n";

const char http_Unauthorized[] PROGMEM =
"HTTP/1.0 401 Unauthorized\r\n"
"Content-Type: text/html\r\n\r\n"
"<h1>401 Unauthorized</h1>";

void homePage()
{
  bfill.emit_p(PSTR("$F"
  "<META HTTP-EQUIV=\"refresh\" CONTENT=\"25\">"
    "<title>Arduino Relais Webserver 2</title>"
    "<h1><center><br /><br /><a href=\"?relais1=$F\">$F</a>"
    "<br /><br /><a href=\"?relais2=$F\">$F</a>"
    "<br /><br /><a href=\"?relais3=$F\">$F</a>"

    "</center></h1>"
    ),
  http_OK,
  relais1Status?PSTR("off"):PSTR("on"),
  relais1Status?PSTR("<font color=\"green\"><b>ON</b></font>"):PSTR("<font color=\"red\">OFF</font>"),
  relais2Status?PSTR("off"):PSTR("on"),
  relais2Status?PSTR("<font color=\"green\"><b>ON</b></font>"):PSTR("<font color=\"red\">OFF</font>"),
  relais3Status?PSTR("off"):PSTR("on"),
  relais3Status?PSTR("<font color=\"green\"><b>ON</b></font>"):PSTR("<font color=\"red\">OFF</font>")

  );
}

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

  pinMode(RELAIS_1, OUTPUT);
  pinMode(RELAIS_2, OUTPUT);
  pinMode(RELAIS_3, OUTPUT);

  if (ether.begin(BUFFER_SIZE, mymac, CS_PIN) == 0)
    Serial.println("Cannot initialise ethernet.");
  else
    Serial.println("Ethernet initialised.");

  ether.staticSetup(myip);

  Serial.println("Setting up DHCP");
  if (!ether.dhcpSetup())
    Serial.println( "DHCP failed");

  ether.printIp("My IP: ", ether.myip);
  ether.printIp("Netmask: ", ether.netmask);
  ether.printIp("GW IP: ", ether.gwip);
  ether.printIp("DNS IP: ", ether.dnsip);

}

void loop()
{
  digitalWrite(RELAIS_1, relais1Status);
  digitalWrite(RELAIS_2, relais2Status);
  digitalWrite(RELAIS_3, relais2Status);

  delay(1);   // necessary for my system
  word len = ether.packetReceive();   // check for ethernet packet
  word pos = ether.packetLoop(len);   // check for tcp packet

  if (pos) {
    bfill = ether.tcpOffset();
    char *data = (char *) Ethernet::buffer + pos;
    if (strncmp("GET /", data, 5) != 0) {
      // Unsupported HTTP request
      // 304 or 501 response would be more appropriate
      bfill.emit_p(http_Unauthorized);
    }
    else {
      Serial.print("----");
      Serial.print(data);
      Serial.println("----");
      data += 5;

      if (data[0] == ' ') {
        // Return home page
        homePage();
      }
      else if (strncmp("?relais1=on ", data, 12) == 0) {
        relais1Status = true;
        bfill.emit_p(http_Found);
      }
      else if (strncmp("?relais2=on ", data, 12) == 0) {
        relais2Status = true;
        bfill.emit_p(http_Found);
      }
      else if (strncmp("?relais3=on ", data, 12) == 0) {
        relais3Status = true;
        bfill.emit_p(http_Found);
      }
      else if (strncmp("?relais1=off ", data, 13) == 0) {
        relais1Status = false;
        bfill.emit_p(http_Found);
      }
      else if (strncmp("?relais2=off ", data, 13) == 0) {
        relais2Status = false;
        bfill.emit_p(http_Found);
      }
      else if (strncmp("?relais3=off ", data, 13) == 0) {
        relais3Status = false;
        bfill.emit_p(http_Found);
      }
      else {
        // Page not found
        bfill.emit_p(http_Unauthorized);
      }
    }

    ether.httpServerReply(bfill.position());    // send http response
  }
}