/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2001 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.openide.execution;

import java.io.FilePermission;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;
import java.net.UnknownServiceException;
import java.security.Permission;

import org.openide.filesystems.*;

/** Special URL connection directly accessing an internal file object.
*
* @author Ales Novak, Petr Hamernik, Jan Jancura, Jaroslav Tulach
 * @deprecated Use {@link URLMapper} instead.
*/
public final class NbfsURLConnection extends URLConnection {
    /** Protocol name for this type of URL. */
    public static final String PROTOCOL = "nbfs"; // NOI18N

    /** Connection created by the fileobject that we want to delegate to */
    private URLConnection del;


    /**
    * Create a new connection to a {@link FileObject}.
    * @param u URL of the connection. Please use {@link #encodeFileObject(FileObject)} to create the URL.
    */
    public NbfsURLConnection (URL u) {
        super (u);
    }


    /** Provides a URL to access a file object.
    * @param fo the file object
    * @return a URL using the correct syntax and {@link #PROTOCOL protocol}
    * @exception FileStateInvalidException if the file object is not valid (typically, if its filesystem is inconsistent or no longer present)
    */
    public static URL encodeFileObject (FileObject fo) throws FileStateInvalidException {
        return fo.getURL ();
    }

    /** Retrieves the file object specified by an internal URL.
    * @param u the url to decode
    * @return the file object that is represented by the URL, or null if the URL is somehow invalid or the file does not exist
    */
    public static FileObject decodeURL (URL u) {
        if (!u.getProtocol ().equals (PROTOCOL)) return null;
        
        FileObject[] fos = URLMapper.findFileObjects(u);
        return (fos.length > 0) ? fos [0] : null;
    }


    /* A method for connecting to a FileObject.
    */
    public void connect() throws IOException {
        if (del != null) return;
        
        synchronized (this) {
            if (del != null) return;
            
            FileObject fo = decodeURL (url);
            if (fo == null) {
                throw new IOException("Cannot find: " + url); // NOI18N
            }
            del = fo.getURL ().openConnection ();
        }
    }

    /*
    * @return InputStream or given FileObject.
    */
    public InputStream getInputStream()
    throws IOException, UnknownServiceException {
        connect ();
        
        return del.getInputStream ();
    }

    /*
    * @return OutputStream for given FileObject.
    */
    public OutputStream getOutputStream()
    throws IOException, UnknownServiceException {
        connect();
        
        return del.getOutputStream ();
    }

    /*
    * @return length of FileObject.
    */
    public int getContentLength() {
        try {
            connect();
            return del.getContentLength ();
        } catch (IOException ex) {
            return 0;
        }
    }


    /** Get a header field (currently, content type only).
    * @param name the header name. Only content-type is guaranteed to be present.
    * @return the value (i.e., MIME type)
    */
    public String getHeaderField(String name) {
        try {
            connect ();
            return del.getHeaderField (name);
        } catch (IOException ex) {
            return super.getHeaderField (name);
        }
    }


    // #13038: delegate to FileURL
    public Permission getPermission() throws IOException {
        if (del != null) {
            return del.getPermission();
        } else {
            // Just a guess.
            return new FilePermission("<>", "read"); // NOI18N
        }
    }
    
}