import java.applet.Applet;

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.text.*;

import java.net.URL;
import java.io.BufferedReader;
import java.io.InputStreamReader;

/*
 * Applet which implement the stock reader excercise.
 */

public class StockReaderApplet extends Applet implements KeyListener{
  // GUI elements

  TextField ticker_prompt = new TextField(6);
  TextField start_prompt = new TextField("01.01.99", 8);
  TextField stop_prompt  = new TextField("31.12.99", 8);
  TextArea result_area = new TextArea("",4,30, TextArea.SCROLLBARS_VERTICAL_ONLY);

  /*
   * The init method builds the user interface.
   */
  public void init(){
    // BorderLayout is a good choice of LayoutManager for this
    // applet. We use the CENTER panel to hold the TextArea, and the
    // the NORTH panel to hold the other components.

    setLayout(new BorderLayout());

    result_area.setEditable(false);
    add(result_area, BorderLayout.CENTER);

    // We put all components that we want at BorderLayout.NORTH
    // on common panel so that they get aligned properly.
    // This panel uses a FlowLayout (which is what we want for this line).
    // This panel is added to the NORTH panel of BorderLayout.

    Panel north = new Panel();
    
    north.add(new Label("Enter a ticker: "));
    north.add(ticker_prompt);
    ticker_prompt.addKeyListener(this);

    north.add(new Label("Start date: "));
    north.add(start_prompt);
    start_prompt.addKeyListener(this);

    north.add(new Label("Stop date: "));
    north.add(stop_prompt);
    stop_prompt.addKeyListener(this);

    add(north, BorderLayout.NORTH);
  }

  public void keyPressed(KeyEvent event) {}
  public void keyTyped(KeyEvent event) {}

  public void keyReleased(KeyEvent event){
    // Check that the key-press came from the ticker_prompt,
    // and that the user pressed the enter key.

    DateFormat df = new SimpleDateFormat("dd.MM.yy");
    Date curDate, strtDate, stpDate;

    try{
      strtDate = df.parse(start_prompt.getText());
      stpDate = df.parse(stop_prompt.getText());
    }catch(Exception e){
      result_area.append("\nIlligal start or stop date!\n\n");
      return;
    }

    if(event.getKeyCode() == KeyEvent.VK_ENTER){
      // Get ticker and read from server.
      try{
	URL stock = new URL("http://www.stud.ifi.uio.no/~in104/Quotes/Oslo/" + ticker_prompt.getText());
	BufferedReader in = new BufferedReader(new InputStreamReader(stock.openStream()));
	String inputLine;
	while ((inputLine = in.readLine()) != null){
	  try{
	    curDate = df.parse(inputLine.substring(0, 8));
	  }catch(Exception e){
	    curDate = new Date();
	  }
	  if(!curDate.before(strtDate) && !curDate.after(stpDate))
	    result_area.append(inputLine + "\n");

	}
	in.close();
	}catch(Exception e){
	  result_area.append("Error while reading URL! (" + e + ")\n");
	}
	result_area.append("\n");
    } //if(event.getKeyCode()...
  } //keyReleased...
} //class StockReaderApplet