/*
 * Copyright (c) 2007-2010 by The Broad Institute, Inc. and the Massachusetts Institute of Technology.
 * All Rights Reserved.
 *
 * This software is licensed under the terms of the GNU Lesser General Public License (LGPL), Version 2.1 which
 * is available at http://www.opensource.org/licenses/lgpl-2.1.php.
 *
 * THE SOFTWARE IS PROVIDED "AS IS." THE BROAD AND MIT MAKE NO REPRESENTATIONS OR WARRANTIES OF
 * ANY KIND CONCERNING THE SOFTWARE, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NONINFRINGEMENT, OR THE ABSENCE OF LATENT
 * OR OTHER DEFECTS, WHETHER OR NOT DISCOVERABLE.  IN NO EVENT SHALL THE BROAD OR MIT, OR THEIR
 * RESPECTIVE TRUSTEES, DIRECTORS, OFFICERS, EMPLOYEES, AND AFFILIATES BE LIABLE FOR ANY DAMAGES OF
 * ANY KIND, INCLUDING, WITHOUT LIMITATION, INCIDENTAL OR CONSEQUENTIAL DAMAGES, ECONOMIC
 * DAMAGES OR INJURY TO PROPERTY AND LOST PROFITS, REGARDLESS OF WHETHER THE BROAD OR MIT SHALL
 * BE ADVISED, SHALL HAVE OTHER REASON TO KNOW, OR IN FACT SHALL KNOW OF THE POSSIBILITY OF THE
 * FOREGOING.
 */

package org.broad.igv.util;

import java.io.File;
import java.io.IOException;

/**
 * @author Joshua Gould
 */
public class BrowserLauncher {

    /**
     * The Java virtual machine that we are running on. Actually, in most cases we only care about the operating system,
     * but some operating systems require us to switch on the VM.
     */
    private static int jvm;

    /**
     * JVM constant for any Windows JVM
     */
    private static final int WINDOWS = 1;

    /**
     * JVM constant for any Mac JVM
     */
    private static final int MAC = 2;

    /**
     * JVM constant for any other platform
     */
    private static final int OTHER = 3;

    /**
     * specified the path to the browser
     */
    private static final int SPECIFIED = 4;

    /**
     * The browser for the system
     */
    private static String specifiedBrowser;

    /**
     * An initialization block that determines the operating system.
     */
    static {
        String osName = System.getProperty("os.name");
        if (osName.startsWith("Mac OS")) {
            jvm = MAC;
        } else if (osName.startsWith("Windows")) {
            jvm = WINDOWS;
        } else {
            jvm = OTHER;
        }
    }

    /**
     * This class should be never be instantiated; this just ensures so.
     */
    private BrowserLauncher() {
    }

    /**
     * Attempts to open the default web browser to the given URL.
     *
     * @param url The URL to open
     * @throws IOException If the web browser could not be located or does not run
     */
    public static void openURL(String url) throws IOException {
        switch (jvm) {
            case MAC:
                Runtime.getRuntime().exec(new String[]{"/usr/bin/open", url});
                break;

            case WINDOWS:
                Process process = Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler " + url);
                // This avoids a memory leak on some versions of Java on Windows.
                // That's hinted at in
                // <http://developer.java.sun.com/developer/qow/archive/68/>.
                try {
                    process.waitFor();
                    process.exitValue();
                } catch (InterruptedException ie) {
                    throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
                }
                break;
            case OTHER:
                if (new File("/usr/bin/gnome-open").exists()) {
                    Runtime.getRuntime().exec(new String[]{"/usr/bin/gnome-open", url});
                } else if (new File("/usr/bin/kde-open").exists()) {
                    Runtime.getRuntime().exec(new String[]{"/usr/bin/kde-open", url});
                }

                break;
            case SPECIFIED:
                process = Runtime.getRuntime().exec(new String[]{specifiedBrowser, url});
                try {
                    process.waitFor();
                    process.exitValue();
                } catch (InterruptedException ie) {
                    throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
                }
                break;
        }
    }

    public static void setSpecifiedBrowser(String s) {
        specifiedBrowser = s;
        jvm = SPECIFIED;
    }

}