/*
 * 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);
  }
}