//===========================================================================
//                                                            " WEB HARVEST "
//                                           HOW TO HARVEST DATA FROM THE WEB
//                                                   Using FastNet Components
//                                                           Nicholas Gessler
//                                                            1 February 2006
//===========================================================================

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
   : TForm(Owner)
{
}
//---------------------------------------------------------------------------

//===========================================================================
//                                                                  VARIABLES
//===========================================================================

// for the general routine
AnsiString text;

// for the special "Get Gold Price" routine:
int p;
AnsiString goldWebAddress;
AnsiString goldText;
AnsiString goldSubText;
AnsiString goldPrice;

//===========================================================================
//                                                                  FUNCTIONS
//===========================================================================

//--------------------------------------------------------------- Get Website
void getWebsite (void) {
   Form1->NMHTTP1->Get(Form1->EditWebAddress->Text);
   Form1->MemoHeader->Text = Form1->NMHTTP1->Header;
   Form1->MemoBody->Text = Form1->NMHTTP1->Body;
   text = Form1->NMHTTP1->Body;

}

//------------------------------------------------------------ Search Website
void searchWebsite (void) {
   Form1->EditSearchStringLength->Text =
      Form1->EditSearchString->Text.Length();
   Form1->EditSearchStringPosition->Text =
      text.Pos(Form1->EditSearchString->Text);
}

//--------------------------------------------------------- Get Price of Gold
void getGoldPrice (void) {

   // go to the gold website
   goldWebAddress =
      "http://cmi-gold-silver.com/gold-silver-daily-spot-prices.html";
   Form1->NMHTTP1->Get(goldWebAddress);

   // display the URL and HTML on the screen
   Form1->EditWebAddress->Text = goldWebAddress;
   Form1->MemoHeader->Text = Form1->NMHTTP1->Header;
   Form1->MemoBody->Text = Form1->NMHTTP1->Body;

   // capture the HTML Body in AnsiStrings
   goldText = Form1->NMHTTP1->Body;
   text = Form1->NMHTTP1->Body;

   // it may not be easy to find what you want
   // here we narrow the search to two steps

   // STEP 1: search for a unique marker near the gold price
   p = goldText.Pos(">Gold</h2");
   Form1->EditGoldMarker->Text = ">Gold</h2";
   Form1->EditGoldMarkerPosition->Text = p;

   // create a new string from the marker to the gold price
   goldSubText = goldText.SubString(p, 200);
   Form1->MemoGoldSubText->Text = goldSubText;

   // STEP 2: search for the first dollar sign
   p = goldSubText.Pos("$");
   goldPrice = goldSubText.SubString(p, 7);
   Form1->EditGoldPrice->Text = goldPrice;
   Form1->EditGoldPricePosition->Text = p;
}

//===========================================================================
//                                                             EVENT HANDLERS
//===========================================================================

//-------------------------------------------------------- Get Website Button
void __fastcall TForm1::ButtonGetWebsiteClick(TObject *Sender)
{
   getWebsite();
}

//-------------------------------------------------- Search for String Button
void __fastcall TForm1::ButtonSearchForStringClick(TObject *Sender)
{
   searchWebsite();
}

//----------------------------------------------------- Get Gold Price Button
void __fastcall TForm1::ButtonGetGoldPriceClick(TObject *Sender)
{
   getGoldPrice();
}

//---------------------------- On Pressing ENTER after Typing the Web Address
void __fastcall TForm1::EditWebAddressKeyPress(TObject *Sender, char &Key)
{
   if (Key == VK_RETURN) getWebsite();
}

//-------------------------- On Pressing ENTER after Typing the Search String
void __fastcall TForm1::EditSearchStringKeyPress(TObject *Sender,
      char &Key)
{
   if (Key == VK_RETURN) searchWebsite();
}

//---------------------------------------------------- Show Connection Status
void __fastcall TForm1::NMHTTP1Connect(TObject *Sender)
{
   StatusBar1->SimpleText = " Connected";
}

//---------------------------------------------------- Show Connection Status
void __fastcall TForm1::NMHTTP1HostResolved(TComponent *Sender)
{
   StatusBar1->SimpleText = " Host Resolved";
}

//---------------------------------------------------- Show Connection Status
void __fastcall TForm1::NMHTTP1PacketRecvd(TObject *Sender)
{
   StatusBar1->SimpleText = " " + IntToStr(NMHTTP1->BytesRecvd) + " bytes of "
      + IntToStr(NMHTTP1->BytesTotal) + " received";
}

//---------------------------------------------------- Show Connection Status
void __fastcall TForm1::NMHTTP1PacketSent(TObject *Sender)
{
   StatusBar1->SimpleText = " " + IntToStr(NMHTTP1->BytesSent) + " bytes of "
      + IntToStr(NMHTTP1->BytesTotal) + " sent";
}

//---------------------------------------------------- Show Connection Status
void __fastcall TForm1::NMHTTP1Success(CmdType Cmd)
{
   StatusBar1->SimpleText = " Success";
}

//---------------------------------------------------------- That's All Folks