package awt;

import awt.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;

 A FileDialog clone *with* working filenamefilter ... 
public class FileDialog extends Dialog implements ActionListener,ItemListener {
	public static final int LOAD = java.awt.FileDialog.LOAD;
	public static final int SAVE = java.awt.FileDialog.SAVE;

	private Frame parentFrame;
	private int mode;
	private String dir,file;
	private FilenameFilter filter;
	private TextField pathField,nameField;
	private Button upButton,newButton,openButton;
	// Pending: implement awt.List.addItemListener() !
	private java.awt.List filelist;

	public FileDialog(Frame parent) {
		this(parent,"");
	}

	public FileDialog(Frame parent,String title) {
		this(parent,title,LOAD);
	}

	public FileDialog(Frame parent,String title,int mode) {
		super(parent,title,true);
		setBackground(Color.lightGray);
		parentFrame = parent;
		this.mode = mode;

		Component comp;
		GridBagLayout gbag;
		setLayout(gbag = new GridBagLayout());
		GridBagConstraints gc = new GridBagConstraints();

		add(comp = new Label("Path:"));
		gc.fill = GridBagConstraints.NONE;
		gc.weightx = 0; gc.weighty = 0;
		gbag.setConstraints(comp,gc);

		add(pathField = new TextField(30));
		pathField.addActionListener(this);
		gc.fill = GridBagConstraints.HORIZONTAL;
		gc.weightx = 1;
		gbag.setConstraints(pathField,gc);

		add(upButton = new Button("Up"));
		gc.fill = GridBagConstraints.NONE;
		gc.weightx = 0;
		gbag.setConstraints(upButton,gc);
		upButton.addActionListener(this);
		
		add(newButton = new Button("New dir ..."));
		gc.gridwidth = GridBagConstraints.REMAINDER;
		gbag.setConstraints(newButton,gc);
		newButton.addActionListener(this);

		add(filelist = new java.awt.List());
		gc.fill = GridBagConstraints.BOTH;
		gc.weightx = gc.weighty = 1;
		gbag.setConstraints(filelist,gc);
		filelist.addActionListener(this);
		filelist.addItemListener(this);

		add(comp = new Label("File:"));
		gc.fill = GridBagConstraints.NONE;
		gc.weightx = gc.weighty = 0;
		gc.gridwidth = 1;
		gbag.setConstraints(comp,gc);

		add(nameField = new TextField(""));
		nameField.addActionListener(this);
		gc.fill = GridBagConstraints.HORIZONTAL;
		gc.weightx = 1;
		gc.gridwidth = GridBagConstraints.REMAINDER;
		gbag.setConstraints(nameField,gc);

		Panel p = new Panel();
		Button b;
		p.add(openButton = new Button((mode == LOAD) ? "Open" : "Save"));
		openButton.addActionListener(this);
		p.add(b = new Button("Cancel"));
		b.addActionListener(this);
		add(p);
		gc.fill = GridBagConstraints.HORIZONTAL;
		gbag.setConstraints(p,gc);

		pack();
		{	// Window is really not high enough
			Dimension siz = getSize();
			setSize(siz.width,siz.height*2);
		}
		// it's the task of the caller to show()
		updatelist();
	}

	public int getMode() { return mode; }
	public void setMode(int m) {
		switch (mode) {
		case LOAD: case SAVE:
			mode = m; break;
		default:
			throw new IllegalArgumentException("illegal file dialog mode "+mode);
		}
	}

	public String getDirectory() { return dir; }
	public void setDirectory(String d) {
		if (d==null || d.length()==0)
			dir = System.getProperty("user.dir");
		else dir = d;
		pathField.setText(d);
	}

	public String getFile() { return file; }
	public void setFile(String d) { nameField.setText(file = d); }

	public FilenameFilter getFilenameFilter() { return filter; }
	public void setFilenameFilter(FilenameFilter f) {
		filter = f;
		updatelist();
	}

	
 useful for debugging 
	protected String paramString() {
		String str = super.paramString();
		if (dir != null) str += ",dir="+dir;	
		return str + (mode==LOAD ? "LOAD" : "SAVE");
	}

	private void enterdir(String name) {
		if (name.endsWith("/"))
			name = name.substring(0,name.length()-1);
		File f;	// destination
		{	File there = new File(name);
			if (there.isAbsolute()) f = there;
			else f = new File(dir,name);
		}
		// try to avoid having "./" and "../" in the dir name
		String canon = null;
		try { canon = f.getCanonicalPath(); } catch (IOException e) {}
		if (canon != null) dir = canon;
		else dir = f.getPath();
		pathField.setText(dir);
		updatelist();
	}

	// Return file name of i-th file in the list
	private String filename(int i) {
		String result = filelist.getItem(i);
		return result.substring(result.indexOf(' ')+1);
	}

	public void itemStateChanged(ItemEvent e) {
		int idx = filelist.getSelectedIndex();
		if (idx < 0) return;
		String name = filelist.getItem(idx);
		if (!new File(dir,name).isDirectory())
			nameField.setText(filename(idx));
	}

	
 Button presses or List double clicks 
	public void actionPerformed(ActionEvent e) {
		String cmd = e.getActionCommand();
		Object src = e.getSource();

		if (src instanceof List) {
			// double click
			String name = filename(filelist.getSelectedIndex());	//nameField.getText();
			File f = new File(dir,name);
//System.out.println("doubleclick "+f+"; dir: "+f.isDirectory());
			if (!f.isDirectory()) {
				file = name;
				dispose();
			} else enterdir(name);
		} else if (src == pathField) {
			enterdir(pathField.getText());
		} else if (src==nameField || cmd.equals("Open") || cmd.equals("Save")) {
			file = nameField.getText();
			if (new File(dir,file).isDirectory()) {
				enterdir(file);
				nameField.setText(file = "");
			} else dispose();
		} else if (cmd.equals("Up")) {
			File f = new File(dir);
			dir = f.getParent();
			pathField.setText(dir);
			updatelist();
		} else if (cmd.equals("New dir ...")) {
			new CreateDir(this,dir);
		} else if (cmd.equals("Cancel")) {
			dir = file = null;
			dispose();
		} else System.out.println(cmd);
	}

	protected void updatelist() {
		File f;

		if (dir==null || dir.length()==0)
			pathField.setText(dir = System.getProperty("user.dir"));
		f = new File(dir);
//System.out.println("updatelist "+f);
		setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
		String [] files = f.list(filter);
//System.out.println("updatelist "+f+" "+files.length+" files");

		filelist.removeAll();
		if (files == null) return;
		// Add files in alphabetically sorted order
		String lastAdded = "";
		while (true) {
			String best = null;
			int besti = 0;
			for (int i = 0; i < files.length; i++) {
				if (files[i] == null) continue;
				if (best == null) {
					best = files[i];
					besti = i;
					continue;
				}
				if (best.compareTo(files[i]) > 0)
					best = files[besti = i];
			}
			if (best == null) break;
			files[besti] = null;
			f = new File(dir,best);
			if (f.isDirectory()) filelist.add(" "+best+"/");
			else switch (mode) {
			case LOAD: if (f.canRead()) filelist.add(f.length()+" "+best);
				break;
			case SAVE: if (f.canWrite()) filelist.add(f.length()+" "+best);
				break;
			}
		}
		setCursor(Cursor.getDefaultCursor());
	}
}

class CreateDir extends Frame implements ActionListener {
	private FileDialog dialog;
	private String parentdir;
	private TextField nameField;

	public CreateDir(FileDialog d,String pardir) {
		super("Create dir in "+pardir);
		dialog = d;
		parentdir = pardir;
		add("North",new Label("Directory name:"));
		add("Center",nameField = new TextField(""));
		Panel p = new Panel();
		Button b;
		p.add(b = new Button("Create dir"));
		b.addActionListener(this);
		p.add(b = new Button("Cancel"));
		b.addActionListener(this);
		add("South",p);
		pack();
		show();
	}

	public void actionPerformed(ActionEvent e) {
		String cmd = e.getActionCommand();

		if (cmd.equals("Cancel")) {
			dispose();
		} else if (cmd.equals("Create dir")) {
			new File(parentdir,nameField.getText()).mkdir();
			dispose();
			dialog.updatelist();
		}
	}
}