/*
 * File    : BrowserLauncher.java
 * Created : 02-jul-2002 18:22
 * Remaked:  01-Feb-2011 17:30
 * By      : fbusquets
 *
 * JClic - Authoring and playing system for educational activities
 *
 * Old version was taken from: Eric Albert's BrowserLauncher class (ejalbert@cs.stanford.edu)
 * New version from BareBonesBrowserLauncher, by Dem Pilafian enhanced by Williem van Engen
 * Adapted by Francesc Busquets
 *
 * @author Eric Albert (ejalbert@cs.stanford.edu) modified by Francesc Busquets (fbusquets@xtec.cat)
 * @version 15.11.27
 */
package edu.xtec.util;

import java.awt.Component;
import java.awt.Desktop;
import java.lang.reflect.Method;
import java.net.URI;
import java.net.URL;
import javax.swing.JOptionPane;

/**
 * Class to open the system's default web browser.
 * <p>
 * Since JClic uses Java 1.6, this class can make direct calls to java.awt.Desktop.browse
 */
public class BrowserLauncher {

    /**
     * Added by fbusquets - command that launches the user's preferred browser *
     */
    private static String preferredBrowser;
    /**
     * Added by fbusquets - Key used to store browser settings in properties files *
     */
    public static final String BROWSER = "browser";

    private static final String errMsg = "Error attempting to launch web browser";

    /**
     * Open a URL
     *
     * @param url {@link URL} to open
     * @param parent parent component for error message dialog
     */
    public static void openURL(URL url, Component parent) {
        openURL(url.toExternalForm(), parent);
    }

    /**
     * Open a string URL
     *
     * @param surl URL to open (as String)
     * @param parent parent component for error message dialog
     */
    //@SuppressWarnings("unchecked") // to support older java compilers
    public static void openURL(String surl, Component parent) {
	// Try java desktop API first (new in Java 1.6)
        // basically: java.awt.Desktop.getDesktop().browse(new URI(url));

        // Replace whitespaces with the URL-encoded expression "%20"
        surl = StrUtils.replace(surl, " ", "%20");

        try {
            Desktop dsk;
            if (Desktop.isDesktopSupported() && (dsk = Desktop.getDesktop()) != null) {
                dsk.browse(new URI(surl));
                return;
            }
        } catch (Exception e) {
        }

        // Failed, resort to executing the browser manually
        String osName = System.getProperty("os.name");
        try {
            // Mac OS has special Java class
            if (osName.startsWith("Mac OS")) {
                Class<?> fileMgr = Class.forName("com.apple.eio.FileManager");
                Method openURL = fileMgr.getDeclaredMethod("openURL", new Class[]{String.class});
                openURL.invoke(null, new Object[]{surl});
                return;
            }

            String[] cmd;

            // Windows execs url.dll
            if (osName.startsWith("Windows")) {
                cmd = new String[]{"rundll32", "url.dll,FileProtocolHandler", surl};

                // else assume unix/linux: call one of the available browsers
            } else {
                String[] browsers = {
                    // user's Preferred browser (will be skipped if null or empty):
                    preferredBrowser,
                    // Freedesktop, http://portland.freedesktop.org/xdg-utils-1.0/xdg-open.html
                    "xdg-open",
                    // Debian
                    "sensible-browser",
                    // Otherwise call browsers directly
                    "chromium", "firefox", "opera", "konqueror", "epiphany", "mozilla", "netscape"};
                String browser = null;
                for (int count = 0; count < browsers.length && browser == null; count++) {
                    if (browsers[count] != null && browsers[count].length() > 0 && Runtime.getRuntime().exec(
                            new String[]{"which", browsers[count]}).waitFor() == 0) {
                        browser = browsers[count];
                    }
                }

                if (browser == null) {
                    //logger.warning("No web browser found");
                    throw new Exception("Could not find web browser");
                }

                cmd = new String[]{browser, surl};
            }

            if (Runtime.getRuntime().exec(cmd).waitFor() != 0) {
                throw new Exception("Error opening page: " + surl);
            }
        } catch (Exception e) {
            JOptionPane.showMessageDialog(parent, errMsg + ":\n" + e.getLocalizedMessage());
        }
    }

    /**
     * Open a URL
     * <p>
     * This is equal to {@link #openURL(URL, Component) openURL(url, null)} so any error dialog will
     * have no parent.
     *
     * @param url {@link URL} to open
     */
    public static void openURL(URL url) {
        openURL(url, null);
    }

    /**
     * Open a string URL
     * <p>
     * This is equal to {@link #openURL(String, Component) openURL(surl, null)} so any error dialog
     * will have no parent.
     *
     * @param surl URL to open (as String)
     */
    public static void openURL(String surl) {
        openURL(surl, null);
    }

    /**
     * Added by fbusquets Sets the path to the user's perferred browser.
     *
     * @param browserCmd The path to the browser to be used by BrowserLaunched
     */
    public static void setPreferredBrowser(String browserCmd) {
        preferredBrowser = StrUtils.nullableString(browserCmd);
    }

    /**
     * Added by fbusquets Gets the path to the user's preferred browser.
     *
     * @param defaultValue The default choice, used only if preferred browser not set.
     * @return The command line corresponding to the user's preferred browser
     */
    public static String getPreferredBrowser(String defaultValue) {
        return StrUtils.secureString(preferredBrowser, defaultValue);
    }

}