/* ======================================================================
   Parts Copyright 2006 University of Leeds, Oxford University, University of the Highlands and Islands.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

====================================================================== */

package org.bodington.server.ims;

import java.io.*;
import java.util.Enumeration;
import javax.swing.tree.*;
import org.w3c.dom.*;

public class PackageItem extends PackageNode
	{
	public PackageItem( Package p, org.w3c.dom.Node n )
		throws ImsException
		{
		super( p, n );
		if ( !(n instanceof Element) )
			throw new ImsException( "Invalid package file. Item must by type of node." );
		Element e = (Element)n;
		if ( !e.getTagName().equals( "item" ) )
			throw new ImsException( "Invalid package file. Item must have item tag element." );

		NodeList nl = e.getChildNodes();
		Element child;
		String tagname;
		for ( int i=0; i<nl.getLength(); i++ )
			{
			if ( !(nl.item( i ) instanceof Element) )
				continue;
				//throw new ImsException( "Invalid package file. Resources can only contain elements." );
			child = (Element)nl.item( i );
			tagname = child.getTagName();

			if ( tagname.equals( "title" ) )
				continue;

			if ( !tagname.equals( "item" ) )
				throw new ImsException( "Invalid package file. Organizations can only contain item and title elements." );

			add( new PackageItem( ims_package, child ) );
			}
		}


	public PackageItem( PackageResource resource )
		throws ImsException
		{
		super( resource.ims_package, null );
		Document doc = resource.dom_node.getOwnerDocument();
		Element item = doc.createElement( "item" );
		item.setAttribute( "identifier", "ITEM" + Math.round( Math.random()*1000000000.0 ) );
		item.setAttribute( "resourceref", resource.getIdentifier() );
		item.setAttribute( "isvisible", "1" );
		dom_node = item;
		
		String title = resource.getHref();
		
		if ( title==null || title.length()==0 )
			title = "untitled";
		int n = title.lastIndexOf( '.' );
		if ( n>0 )
			title = title.substring( 0, n );
		
		setTitle( title );
		}

	public PackageItem( PackageItem other )
		throws ImsException
		{
		super( other.ims_package, null );
		Document doc = other.dom_node.getOwnerDocument();
		Element item = doc.createElement( "item" );
		item.setAttribute( "resourceref", other.getResourceRef() );
		item.setAttribute( "isvisible", "1" );
		dom_node = item;

		setTitle( other.getTitle() );
		}

	public void canAdd( MutableTreeNode child )
		{
		if ( !(child instanceof PackageItem) )
			throw new IllegalStateException( "This node only accepts additional item nodes." );
		}

	public void drop( PackageNode other, int index )
		throws ImsException
		{
		if ( other instanceof PackageResource )
			{
			PackageItem new_item = new PackageItem( (PackageResource)other );
			insert( new_item, index );
			return;
			}

		if ( other instanceof PackageItem )
			{
			//PackageItem new_item = new PackageItem( (PackageItem)other );
			insert( other, index );
			return;
			}
		}

	public boolean canDrop( PackageNode other )
		{
		return (other instanceof PackageItem) || (other instanceof PackageResource);
		}

	public void setTitle( String title )
		{
		Element t;
		Text text;
		Element e = (Element)dom_node;
		Document doc = dom_node.getOwnerDocument();

		NodeList nl = e.getElementsByTagName( "title" );
		
		if ( nl.getLength() == 0 )
			{
			t = doc.createElement( "title" );
			e.appendChild( t );
			
			text = doc.createTextNode( title );
			t.appendChild( text );
			}

		
		if ( nl.getLength() > 0 )
			{
			t = (Element)nl.item( 0 );
			NodeList nl2 = t.getChildNodes();
			Node n;
			for ( int i=0; i<nl2.getLength(); i++ )
				{
				n = nl2.item( i );
				if ( n.getNodeType() != Node.TEXT_NODE )
					continue;
				t.removeChild( n );
				}

			text = doc.createTextNode( title );
			t.appendChild( text );
			}
		}
	
	public String getTitle()
		{
		Element e = (Element)dom_node;
		NodeList nl = e.getElementsByTagName( "title" );
		if ( nl.getLength() > 0 )
			{
			Element t = (Element)nl.item( 0 );
			NodeList nl2 = t.getChildNodes();
			Node n;
			CharacterData title;
			for ( int i=0; i<nl2.getLength(); i++ )
				{
				n = nl2.item( i );
				if ( n.getNodeType() != Node.TEXT_NODE )
					continue;
				title = (CharacterData)n;
				return title.getData();
				}
			}
		
		return "untitled";
		}

	public String getResourceRef()
		{
		Element e = (Element)dom_node;
		return e.getAttribute( "resourceref" );
		}
		
	public String getHRef( Package r_pack )
		{
		String resref = getResourceRef();
		
		if ( resref == null )
			return null;
		
		PackageResource resource = r_pack.findResourceByIdentifier( resref );
		if ( resource == null )
			return null;
			
		return resource.getHref();
		}
		
	public void writeMenu( PrintWriter writer, Package r_pack )
		{
		String href = getHRef( r_pack );
		String title = getTitle();
		
		writer.print( "<item" );
		if ( href !=null )
			{
			writer.print( " href=\"" );
			writer.print( href );
			writer.print( "\"" );
			}
		writer.println( ">" );
		writer.print( "<title>" );
		
		if ( title!=null )
			writer.print( title );
			
		writer.println( "</title>" );
		
		PackageNode node;
		PackageItem item;
		Enumeration enumeration = this.children();
		while ( enumeration.hasMoreElements() )
			{
			node = (PackageNode)enumeration.nextElement();
			if ( !(node instanceof PackageItem) )
				continue;
			item = (PackageItem)node;
			item.writeMenu( writer, r_pack );
			}

		writer.println( "</item>" );
		}
		
	public String toString()
		{
		return getTitle();
		}

	}