package test;

import java.io.File;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.zkoss.zul.DefaultTreeModel;
import org.zkoss.zul.TreeNode;

public class FileTreeNode implements TreeNode, Serializable{
	private static final long serialVersionUID = 1L;

	private boolean checkedChildren = false;
	private ArrayList<FileTreeNode> children;
	private final File file;
	private DefaultTreeModel model;
	private final FileTreeNode parent;

	public FileTreeNode(final File f, final FileTreeNode p){
		file = f;
		parent = p;
	}

	public FileTreeNode(final String n){
		file = new File(n);
		parent = null;
	}

	@Override
	public void add(final TreeNode child){
		throw new UnsupportedOperationException("add");
	}

	private void ensureChildren(){
		if(!checkedChildren){
			if(isLeaf()){
				children = null;
			}else{
				final File[] files = file.listFiles();
				if(files != null){
					Arrays.sort(files);

					final ArrayList<FileTreeNode> tmp = new ArrayList<FileTreeNode>();
					for(final File f : files){
						if(!f.isHidden()){
							final FileTreeNode child = new FileTreeNode(f, this);
							tmp.add(child);
						}
					}
					children = tmp;
				}else{
					children = new ArrayList<FileTreeNode>(1);
				}
				System.out.println("ensure children : " + file + "\t" + children.size());
			}
			checkedChildren = true;
		}
	}

	@Override
	public FileTreeNode getChildAt(final int childIndex){
		ensureChildren();

		if(childIndex < 0 || getChildCount() <= childIndex){
			return null;
		}
		return children.get(childIndex);
	}

	@Override
	public int getChildCount(){
		ensureChildren();
		if(children == null){
			return 0;
		}
		return children.size();
	}

	@Override
	public List<FileTreeNode> getChildren(){
		ensureChildren();
		return children;
	}

	@Override
	public File getData(){
		return file;
	}

	@Override
	public int getIndex(final TreeNode node){
		ensureChildren();

		if(getChildCount() < 1){
			return -1;
		}
		return children.indexOf(node);
	}

	@Override
	public DefaultTreeModel getModel(){
		if(parent != null){
			return parent.getModel();
		}
		return model;
	}

	@Override
	public FileTreeNode getParent(){
		return parent;
	}

	public String getRenderName(){
		if(isLeaf()){
			return file.getName();
		}else{
			return "/" + file.getName();
		}
	}

	@Override
	public void insert(final TreeNode child, final int index){
		throw new UnsupportedOperationException("insert");
	}

	@Override
	public boolean isLeaf(){
		return !file.isDirectory();
	}

	@Override
	public void remove(final int index){
		throw new UnsupportedOperationException("remove");
	}

	@Override
	public void remove(final TreeNode child){
		throw new UnsupportedOperationException("remove");
	}

	@Override
	public void setData(final Object data){
		throw new UnsupportedOperationException("setData");
	}

	@Override
	public void setModel(final DefaultTreeModel m){
		if(m != null && parent != null){
			throw new IllegalStateException("Only root allowed, " + this);
		}
		model = m;
	}
}