/*
 * FindBugs - Find Bugs in Java programs
 * Copyright (C) 2006, University of Maryland
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston MA 02111-1307, USA
 */

package edu.umd.cs.findbugs.util;

import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;

import edu.umd.cs.findbugs.SystemProperties;
import edu.umd.cs.findbugs.ba.MethodUnprofitableException;

/**
 * 
 */
public class LaunchBrowser {

	public static final boolean launchFirefox = SystemProperties.getBoolean("findbugs.launchFirefox")
				&& "Linux".equals(SystemProperties.getProperty("os.name"));
	private static Object desktopObject;
	private static Method desktopBrowseMethod;
	private static boolean launchViaExecFailed = false;
	
	static {
		try {
			Class <?> desktopClass = Class.forName("java.awt.Desktop");
			desktopObject = desktopClass.getMethod("getDesktop").invoke(null);
			desktopBrowseMethod = desktopClass.getMethod("browse", URI.class);
		}  catch (Exception e) {
			assert true;
		} 
			}

	static boolean desktopFeasible() {
		return desktopObject != null && desktopBrowseMethod != null;
	}
	
	static boolean webstartFeasible() {
		return JavaWebStart.jnlpShowDocumentMethod != null && JavaWebStart.jnlpBasicService != null;
	}
	static boolean showDocumentViaDesktop(URL u) {
		
		if (desktopObject != null && desktopBrowseMethod != null) try { 
			 viaDesktop(u.toURI());
			 return true;
		} catch (InvocationTargetException ite) {
			assert true;
		} catch (IllegalAccessException iae) {
			assert true;
		} catch (IllegalArgumentException e) {
			assert true;
        } catch (URISyntaxException e) {
        	assert true;
        }
        return false;
	}

	static void viaDesktop(URI u) throws IllegalAccessException, InvocationTargetException, URISyntaxException {
	    if (desktopBrowseMethod == null)
	    	throw new UnsupportedOperationException("Launch via desktop not available");
	    desktopBrowseMethod.invoke(desktopObject, u);
    }

	
	static boolean showDocumentViaExec(URL url) {
		if (launchFirefox && !launchViaExecFailed) {
			try {
				Process p = launchFirefox(url);
				Thread.sleep(20);
				int exitValue = p.exitValue();
				if (exitValue != 0) {
					launchViaExecFailed = true;
					return false;
				} 
				return true;
			} catch (IllegalThreadStateException e) {
				return true;
			} catch (Exception e) {
				launchViaExecFailed = true;
			}
		}
		return false;
	
	}

	static Process launchFirefox(URL url) throws IOException {
	    ProcessBuilder builder = new ProcessBuilder("firefox", url.toString() );
	    Process p = builder.start();
	    return p;
    }
	/** 
	 * attempt to show the given URL.
	 * will first attempt via the JNLP api, then will try showViaExec().
	 * @param url the URL
	 * @return true on success
	 */
	public static boolean showDocument(URL url) {
		
		if (showDocumentViaExec(url))
			return true;
		if (showDocumentViaDesktop(url))
			return true;
		if (JavaWebStart.showViaWebStart(url))
			return true;
		return false;
	

	}

	
}