/*
---------------------------------------------------------
-             Web control relay with Arduino            - 
---------------------------------------------------------
Ethernet module "ENC28J60" is connected to the Arduino :
VCC - 3.3V   Arduino
GND - GND    Arduino
SCK - Pin 13 Arduino
SO  - Pin 12 Arduino
SI  - Pin 11 Arduino
CS  - Pin 10 Arduino

The relay is connected to the Arduino so:
VCC - 5V     Arduino
In1 - Pin 2  Arduino
In2 - Pin 3  Arduino
...
In7 - Pin 8  Arduino
In8 - Pin 9  Arduino
GND - GND    Arduino
---------------------------------------------------------
*/

#include <EtherCard.h>

// Define number of relays (MAX 8)
#define NB_PINS 8

// ethernet interface mac address, must be unique on the LAN
static byte mymac[] = { 0x74,0x69,0x69,0x2D,0x30,0x31 };
static byte myip[] = { 192,168,0,200 };

// Declare PinStatus and LedPins before BufferFiller declaration
boolean PinStatus[NB_PINS];

int LedPins[NB_PINS];

// buffer[500] for 4 relays
// increase size buffer for more relays
byte Ethernet::buffer[800];
BufferFiller bfill;

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>";

//---------------------------------------------------------
// Web page
void homePage()
{
    bfill.emit_p(PSTR("$F"
    "<title>ArduinoPIN Webserver</title>"
    "<p align=center><font size=10>"
    ),
    http_OK);
    for(int i = 0; i <= NB_PINS-1; i++)
    {
        bfill.emit_p(PSTR(
        "R$D: <a href='?P$D=$F' style=color:$F>$F</a><br />"
        ),
        i+1,
        i+1,
        PinStatus[i]?PSTR("off"):PSTR("on"),
        PinStatus[i]?PSTR("green"):PSTR("red"),
        PinStatus[i]?PSTR("ON"):PSTR("OFF"));
    }
    bfill.emit_p(PSTR(
    "</font></p>"
    ));  
}

//---------------------------------------------------------
void setup()
{
    Serial.begin(9600);
    Serial.print("Setup ");
    for(int i = 0; i <= NB_PINS-1; i++)
    {
        // Pins on Arduino begin from PIN 2 to PIN 9
        LedPins[i] = i+2;
    }

    // if (ether.begin(sizeof Ethernet::buffer, mymac) == 0).
    // and change it (CS-pin) to pin 10.
    Serial.println(F("\nConnecting..."));
    if (ether.begin(sizeof Ethernet::buffer, mymac,10) == 0);
        Serial.println(F("Failed to access Ethernet controller"));
    if (!ether.dhcpSetup()); 
        Serial.println(F("DHCP failed"));
    Serial.print("Connected\n");

    ether.printIp("My Router IP: ", ether.myip); 

    //ether.staticSetup(myip);

    ether.printIp("My SET IP: ", ether.myip); 

    // Debug
    Serial.print("\n");
    Serial.print("|-------------------------------------------|\n");
    Serial.print("| Actions | LedPin       /        PinStatus |\n");
    Serial.print("|-------------------------------------------|\n");
    Serial.print("| Init    | ");

    for(int i = 0; i <= NB_PINS-1; i++)
    {
        // Initialization of pin mode and pin status
        pinMode(LedPins[i],OUTPUT); 
        digitalWrite (LedPins[i],HIGH);
        PinStatus[i]=false;
        // Debug
        Serial.print(LedPins[i]);
        Serial.print("/");
        Serial.print(PinStatus[i]);
        Serial.print(" ");
    }
    Serial.print("\n");
}

//---------------------------------------------------------
void loop()
{

    delay(1);

    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) {
            bfill.emit_p(http_Unauthorized);
        }
        else {
            data += 5;
            int relay=data[2] - 48; // ASCII code for the character '0' is decimal 48
            if (data[0] == ' ') {
                // If change on home page, execute function.
                homePage();
                //Debug
                for (int i = 0; i <= NB_PINS-1; i++)digitalWrite(LedPins[i],!PinStatus[i]);
                    Serial.print("| F5      | ");
            } else if( relay>0 && relay<=NB_PINS ) {
                data += 4;
                if (strncmp("on ", data, 2) == 0) {
                    PinStatus[relay-1] = true;        
                    bfill.emit_p(http_Found);
                    // Debug
                    Serial.print("| R");
                    Serial.print(relay-1);
                    Serial.print(" ON   | ");
                } else if (strncmp("off ", data, 3) == 0) {
                    PinStatus[relay-1] = false;
                    bfill.emit_p(http_Found);
                    // Debug
                    Serial.print("| R");
                    Serial.print(relay-1);
                    Serial.print(" OFF  | ");
                }
            }
            else {
                // Page not found
                bfill.emit_p(http_Unauthorized);
            }
            // Debug
            for(int i = 0; i <= NB_PINS-1; i++)
            {
                Serial.print(LedPins[i]);
                Serial.print("/");
                Serial.print(PinStatus[i]);
                Serial.print(" ");
            }
            Serial.print("\n");
        }
        ether.httpServerReply(bfill.position());    // send http response
    }
}