/*****************************************************************************
* $Id: URLDialog.java,v 1.1.1.1 2000/03/29 22:58:15 kkeys Exp $
*
* File: URLDialog.java	Name:URLDialog
* Goal: To create a FilenameDialog that works for URLs.
* it list the contains of a url and the allow the user to
* select a given file out of those in the URL of a dir.
*
* Written: Bradley Huffaker
* For: Cooperative Association for Internet Data Analysis
******************************************************************************
******************************************************************************
By accessing this software, URLDIALOG, you are duly informed of and 
agree to be bound by the conditions described below in this notice:
 
This software product, URLDIALOG, is developed by Bradley Huffaker, and
Jaeyeon Jung copyrighted(C) 1998 by the University of California, 
San Diego (UCSD), with all rights reserved.  UCSD administers the NLANR 
Cache grants, NCR-9796082 and NCR-9616602, under which most of this code 
was developed.
 
There is no charge for URLDIALOG software. You can redistribute it and/or
modify it under the terms of the GNU General Public License, v. 2 dated
June 1991 which is incorporated by reference herein.  URLDIALOG is
distributed WITHOUT ANY WARRANTY, IMPLIED OR EXPRESS, OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE or that the use of
it will not infringe on any third party's intellectual property
rights.
 
You should have received a copy of the GNU GPL along with the URLDIALOG
program.  Copies can also be obtained from
http://www.gnu.org/copyleft/gpl.html or by writing to
 
                        University of California, San Diego
                        SDSC/CAIDA/NLANR
                        9500 Gilman Dr., MS-0505
                        La Jolla, CA 92093 - 0505  USA
 
  Or contact INFO@NLANR.NET
*****************************************************************************/ 
package bhuffake.plankton;
import java.awt.*;
import java.io.*;
import java.net.URL;

public class URLDialog extends Dialog
{
	// Filter that test for acceptable names.
	NameFilter filter = new NameFilter();
	
	// The List that will display and allow for selection of files
	List list = new List();
	
	// The List that will display directories
	List dirList = new List();

	// Holds the file they selected
	String file_address = null;
	// Holds the url of the directory in which  to look
	String address = null;
	String full_address;

	// Displays the current directory
	TextField current_dir = new TextField("                 ");
	String[] dirs = new String[20];
	int dir_index = 0;

	// Control Buttons
	Button Accept = new Button("Accept");
	Button Cancel = new Button("Cancel");

	// Flags if a error_occured
	boolean error_occured = false;
	// Flag for accepted or not
	boolean accpted = false;

	// The number of lines read
	int linenum = 0;

	FileInterface parent;
	public URLDialog(FileInterface parent_input, String address_input)
	{
		super((Frame)parent_input,"Choose Data File",true);
		parent = parent_input;	

		address = address_input;
		resize(250,200);

		current_dir.setEditable(false);

		Panel buttons = new Panel();
		buttons.setLayout(new BorderLayout());
		buttons.add("West",Accept);
		buttons.add("East",Cancel);
	
		Panel dir_panel = new Panel();
		Label dir_label = new Label("Directorys");
		dir_panel.setLayout(new BorderLayout());
		dir_panel.add("North",dir_label);
		dir_panel.add("Center",dirList);

		Panel file_panel = new Panel();
		Label file_label = new Label("Files");
		file_panel.setLayout(new BorderLayout());
		file_panel.add("North",file_label);
		file_panel.add("Center",list);

		setLayout(new BorderLayout());
		add("North",current_dir);
		add("Center",file_panel);
		add("West",dir_panel);
		add("South",buttons);
	}

	public void Show()
	{	
		setUp();
		((Window)this).show();
	}

	protected void setUp()
	{
		if (list.countItems() > 0)
			list.clear();
		if (dirList.countItems() > 0)
			dirList.clear();
		URL url = null;
		InputStream is = null;
		if (address == null)
		{
			Error("address is null");
		}
		else
		{
			full_address = "";
			for(int index=0;index < dir_index;index++)
			{
				full_address = full_address +"/" 
					+ dirs[index];
			}
			current_dir.setText(full_address);
			full_address = address + full_address;
			try {
				url = new URL(full_address);
				is = url.openStream();
/*
			} catch (MalformedURLException e0) {
				Error(e0.toString());
*/
			} catch (IOException e1) {
				Error(e1.toString());
			}
		}
		if (is == null)
			return;

		if (dir_index > 0)
			dirList.addItem("..");
		error_occured = false;
		int length = 0;
		int current_length = 0;
		byte[] bytes = new byte[256];
		char[] buffer = new char[256];
		boolean working = true;
		linenum = 0;
		try {
		  do {
		    length =is.read(bytes);
//System.err.println("length:" + length + "<>" + bytes.length);
		    if (length < 0)
		    {
		      length = 0;
		      bytes[length++] = '\n';
		      working = false;
		    }
		    for (int offset=0; offset < length; offset++)
		    {
		      if (current_length > buffer.length)
		      {
		        char[] temp = new char[(int)(buffer.length*1.1)];
		        for (int index=0;index < buffer.length;index++)
		          temp[index] = buffer[index];
		        buffer = temp;
		      }
		      buffer[current_length] = (char) bytes[offset];
		      if (buffer[current_length] == '\n')
		      {
		        ParseString(current_length,buffer);
		        current_length = 0;
		        linenum++; 
		    }
		      else
		        current_length++;
		    }
	 	  } while (working);
		} catch (IOException e1) {
			Error(e1.toString());
		}
	}

	public void ParseString(int length, char[] buffer)
	{
//System.err.println( "PraseString:"+length);
		// Current possition in the string
		int index;

		// Attempt to find a directory
		// a tag for 'alt="[dir]"'

		boolean isDir = false;
		final char[] DIR= {'a', 'l', 't', '=', '"', '[', 'd', 'i'
			,'r' ,']' ,'"'};

		index = match(length,buffer,0,DIR);
		
		if (index == length)
		{
			index = 0;
			isDir = false;
		}
		else
			isDir = true;

		
		// Attempt to find the HTMP tag for <a href=" at the front
		// Where we want to capture xxx

		final char[] MATCH_FRONT = {'a', ' ', 'h', 'r', 'e', 'f',
			'=' ,'\"'};
		index = match(length,buffer,index,MATCH_FRONT);

		if (index == length)
			return;

		if (!isDir)
		{
			// Attepmt to match a .fvl" at the end

			int start = index;
			final char[] MATCH_END = {'.','f','v','l','\"'};
			index = match(length,buffer,index,MATCH_END);
			index--;
			if (start == index || index == length-1)
				return;
			list.addItem(new String(buffer,start,index-start));
		}
		else
		{
			// Makes sure it is not the home direcoty
			if (buffer[index] == '/')
				return;

			// Attempts to match " at the end
			int start = index;
			final char[] END = {'"'};
			index = match(length,buffer,index,END);
			index--;
			if (start == index || index == length-1)
				return;
			dirList.addItem(new String(buffer,start,index-start));
		}
	}

	public int match(int length, char[] buffer, int start,char[] match)
	{
//System.err.println( length +":"+new String(buffer,0,length));
		int match_index = 0;
		int index =start;
		while (index < length && match_index < match.length)
		{
			char b_char = buffer[index];
			char m_char = match[match_index];
			if (m_char == b_char ||
			  		m_char == (char)(b_char+'a'-'A'))
				match_index++;
			else
				match_index = 0;
			index++;
		}
		return index;
	}
	
	public String getAddress()
	{
		return file_address;
	}

	public void Error(String msg)
	{
		error_occured = true;
		System.err.println(msg);
		if (list.countItems() > 0)
			list.clear();	
		list.addItem(msg);
	}

	public boolean handleEvent (Event event)
	{
		if (event.id == Event.ACTION_EVENT)
		{
			if (event.target == dirList)
			{
				String dir = dirList.getSelectedItem();
				if (dir.equals(".."))
				{
					if (dir_index > 0)
					{
						dir_index--;
						setUp();
					}
				}
				else
				{
					if (dir_index == dirs.length)
					{
					  String[] temp = new String[
						(int)(dirs.length*1.1)];
					  for(int i=0;i<dirs.length;i++)
					    temp[i] = dirs[i];
					  dirs = temp;
					}
					dirs[dir_index++] = dir;
					setUp();
				}
			}
		  
						
						
			if (event.target == Accept || event.target == list)
			{
				file_address = null;
				String name = list.getSelectedItem();
				if (!error_occured && name != null
					&& address != null)
				{
					file_address= full_address + "/" +
						list.getSelectedItem();
					parent.setFile(file_address);
					hide();
				}
			}
			else if (event.target == Cancel)
			{
				file_address = null;
				hide();
			}
		}
		return super.handleEvent(event);
	}
}