/*****************************************************/
/*          This java file is a part of the          */
/*                                                   */
/*           -  Plouf's Java IRC Client  -           */
/*                                                   */
/*   Copyright (C)  2002 - 2005 Philippe Detournay   */
/*                                                   */
/*         All contacts : theplouf@yahoo.com         */
/*                                                   */
/*  PJIRC is free software; you can redistribute     */
/*  it and/or modify it under the terms of the GNU   */
/*  General Public License as published by the       */
/*  Free Software Foundation; version 2 or later of  */
/*  the License.                                     */
/*                                                   */
/*  PJIRC is distributed in the hope that it will    */
/*  be useful, but WITHOUT ANY WARRANTY; without     */
/*  even the implied warranty of MERCHANTABILITY or  */
/*  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU   */
/*  General Public License for more details.         */
/*                                                   */
/*  You should have received a copy of the GNU       */
/*  General Public License along with PJIRC; if      */
/*  not, write to the Free Software Foundation,      */
/*  Inc., 59 Temple Place, Suite 330, Boston,        */
/*  MA  02111-1307  USA                              */
/*                                                   */
/*****************************************************/

package irc.security;

import irc.EventDispatcher;

import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Dialog;
import java.awt.Frame;
import java.awt.Label;
import java.awt.Panel;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;

/**
 * The security provider. Provides an interface for accessing protected data or
 * operation.
 */
public class SecurityProvider implements ActionListener {
	private SecuredProvider _provider;
	// private Object _lock=new Object();
	private boolean _answer;

	/**
	 * Create a new SecurityProvider.
	 */
	public SecurityProvider() {
		if (tryProvider("MS"))
			return;
		_provider = new DefaultSecuredProvider();
	}

	private boolean tryProvider(String name) {
		SecuredProvider old = _provider;
		try {
			Class cl = Class.forName("irc.security.prv.Specific" + name + "SecuredProvider");
			_provider = (SecuredProvider) cl.newInstance();
			if (!_provider.tryProvider())
				throw new Exception();
			return true;
		} catch (Exception ex) {
			_provider = old;
			return false;
		}
	}

	/**
	 * Get the used provider name.
	 * 
	 * @return used provider name.
	 */
	public String getProviderName() {
		return _provider.getName();
	}

	/**
	 * Get a new Socket.
	 * 
	 * @param host
	 *          server host.
	 * @param port
	 *          server port.
	 * @throws UnknownHostException
	 *           is host is not found.
	 * @throws IOException
	 *           if an error occurs.
	 * @return a new Socket.
	 */
	public Socket getSocket(String host, int port) throws UnknownHostException, IOException {
		try {
			Socket ans = (Socket) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getSocket", new Object[] {
					host, new Integer(port) });
			return ans;
		} catch (InterruptedException ex) {
			throw new IOException("Interrupted");
		} catch (Throwable ex) {
			throw new IOException(ex.getClass().getName() + " : " + ex.getMessage());
		}
	}

	/**
	 * Get a new ServerSocket.
	 * 
	 * @param port
	 *          local port.
	 * @return the created server socket.
	 * @throws IOException
	 *           if an error occurs.
	 */
	public ServerSocket getServerSocket(int port) throws IOException {
		try {
			return (ServerSocket) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getServerSocket",
					new Object[] { new Integer(port) });
		} catch (InterruptedException ex) {
			throw new IOException("Interrupted");
		} catch (Throwable ex) {
			throw new IOException(ex.getClass().getName() + " : " + ex.getMessage());
		}
	}

	/**
	 * Display a request for confirmation.
	 * 
	 * @param parent
	 *          parent frame, or null if headless.
	 * @param title
	 *          the message title.
	 * @param msg
	 *          the message.
	 * @return true if the user replied yes, false otherwise.
	 */
	public boolean confirm(Frame parent, String title, String msg) {
		Dialog f;

		Frame tmp = null;

		if (parent == null) {
			tmp = new Frame();
			f = new Dialog(tmp, title, true);
		} else {
			f = new Dialog(parent, title, true);
		}

		f.setLayout(new BorderLayout());
		f.add(new Label(msg), BorderLayout.CENTER);
		Button b1 = new Button("Yes");
		Button b2 = new Button("No");
		Panel p = new Panel();
		f.setResizable(false);
		f.add(p, BorderLayout.SOUTH);
		p.add(b1);
		p.add(b2);
		b1.addActionListener(this);
		b2.addActionListener(this);
		f.pack();
		_answer = false;
		f.show();
		/*
		 * synchronized(_lock) { try { _lock.wait(); } catch(InterruptedException
		 * ex) { } }
		 */

		b1.removeActionListener(this);
		b2.removeActionListener(this);

		f.hide();
		f.dispose();
		f = null;

		if (tmp != null) {
			tmp.hide();
			tmp.dispose();
			tmp = null;
		}

		return _answer;
	}

	@Override
	public void actionPerformed(ActionEvent e) {
		Button b = (Button) e.getSource();
		_answer = false;
		if (b.getLabel().equals("Yes"))
			_answer = true;
		/*
		 * synchronized(_lock) { _lock.notifyAll(); }
		 */
		((Window) (b.getParent().getParent())).hide();
	}

	/**
	 * Get an FileInputStream from a local file.
	 * 
	 * @param file
	 *          the local file.
	 * @throws IOException
	 *           if an error occurs.
	 * @return an FileInputStream from the file.
	 */
	public FileInputStream getFileInputStream(File file) throws IOException {
		if (!confirm(null, "Security warning", "Authorize file read action on " + file + "?"))
			throw new IOException("User denied access");

		try {
			return (FileInputStream) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getFileInputStream",
					new Object[] { file });
		} catch (InterruptedException ex) {
			throw new IOException("Interrupted");
		} catch (Throwable ex) {
			throw new IOException(ex.getMessage());
		}
	}

	/**
	 * Get an FileOutputStream to a local file.
	 * 
	 * @param file
	 *          the local file.
	 * @throws IOException
	 *           if an error occurs.
	 * @return an FileOutputStream from the file.
	 */
	public FileOutputStream getFileOutputStream(File file) throws IOException {
		if (!confirm(null, "Security warning", "Authorize file write action on " + file + "?"))
			throw new IOException("User denied access");

		try {
			return (FileOutputStream) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getFileOutputStream",
					new Object[] { file });
		} catch (InterruptedException ex) {
			throw new IOException("Interrupted");
		} catch (Throwable ex) {
			throw new IOException(ex.getMessage());
		}
	}

	/**
	 * Get the file size.
	 * 
	 * @param file
	 *          the file to get size.
	 * @return the file size, of a negative value if not able.
	 */
	public int getFileSize(File file) {
		try {
			return ((Integer) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getFileSize",
					new Object[] { file })).intValue();
		} catch (Throwable ex) {
			return -1;
		}
	}

	/**
	 * Open a load file dialog with the given title and return the user choice.
	 * 
	 * @param title
	 *          dialog title.
	 * @return user choice.
	 */
	public File getLoadFile(String title) {
		try {
			return (File) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getLoadFile",
					new Object[] { title });
		} catch (Throwable ex) {
			return null;
		}
	}

	/**
	 * Open a save file dialog with the given title and return the user choice.
	 * 
	 * @param title
	 *          dialog title.
	 * @return user choice.
	 */
	public File getSaveFile(String title) {
		try {
			return (File) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getSaveFile",
					new Object[] { title });
		} catch (Throwable ex) {
			return null;
		}
	}

	/**
	 * Open a save file dialog with the given title and return the user choice.
	 * 
	 * @param file
	 *          default target file.
	 * @param title
	 *          dialog title.
	 * @return user choice.
	 */
	public File getSaveFile(String file, String title) {
		try {
			return (File) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getSaveFile", new Object[] { file,
					title });
		} catch (Throwable ex) {
			return null;
		}
	}

	/**
	 * Get the local host address.
	 * 
	 * @return local host address.
	 * @throws UnknownHostException
	 *           if error occurs.
	 */
	public InetAddress getLocalHost() throws UnknownHostException {
		try {
			return (InetAddress) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "getLocalHost",
					new Object[] {});
		} catch (InterruptedException ex) {
			throw new UnknownHostException("Unable to resolve");
		} catch (Throwable ex) {
			throw new UnknownHostException(ex.getMessage());
		}
	}

	/**
	 * Perform a dns resolve of the given address.
	 * 
	 * @param addr
	 *          address to resolve.
	 * @return resolved address.
	 */
	public String resolve(InetAddress addr) {
		try {
			return (String) EventDispatcher.dispatchEventAsyncAndWaitExSecurity(_provider, "resolve", new Object[] { addr });
		} catch (Throwable ex) {
			return null;
		}
	}

}