/*
    * Copyright (C) 2007-2012 Argeo GmbH
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *         http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.argeo.osgi.boot;
  
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.lang.reflect.Method;
  import java.util.ArrayList;
  import java.util.List;
  
  import org.eclipse.core.runtime.adaptor.EclipseStarter;
  import org.osgi.framework.BundleContext;
  
  /** Command line interface. */
  public class Launcher {
  
  	public static void main(String[] args) {
  		// Try to load system properties
  		String systemPropertiesFilePath = getProperty(OsgiBoot.PROP_ARGEO_OSGI_BOOT_SYSTEM_PROPERTIES_FILE);
  		if (systemPropertiesFilePath != null) {
  			FileInputStream in;
  			try {
  				in = new FileInputStream(systemPropertiesFilePath);
  				System.getProperties().load(in);
  			} catch (IOException e1) {
  				throw new RuntimeException("Cannot load system properties from " + systemPropertiesFilePath, e1);
  			}
  			if (in != null) {
  				try {
  					in.close();
  				} catch (Exception e) {
  					// silent
  				}
  			}
  		}
  
  		// Start main class
  		startMainClass();
  
  		// Start Equinox
  		BundleContext bundleContext = null;
  		try {
  			bundleContext = EclipseStarter.startup(args, null);
  		} catch (Exception e) {
  			throw new RuntimeException("Cannot start Equinox.", e);
  		}
  
  		// OSGi bootstrap
  		OsgiBoot osgiBoot = new OsgiBoot(bundleContext);
  		osgiBoot.bootstrap();
  	}
  
  	protected static void startMainClass() {
  		String className = getProperty(OsgiBoot.PROP_ARGEO_OSGI_BOOT_APPCLASS);
  		if (className == null)
  			return;
  
  		String line = System.getProperty(OsgiBoot.PROP_ARGEO_OSGI_BOOT_APPARGS, "");
  
  		String[] uiArgs = readArgumentsFromLine(line);
  
  		try {
  			// Launch main method using reflection
  			Class<?> clss = Class.forName(className);
  			Class<?>[] mainArgsClasses = new Class[] { uiArgs.getClass() };
  			Object[] mainArgs = { uiArgs };
  			Method mainMethod = clss.getMethod("main", mainArgsClasses);
  			mainMethod.invoke(null, mainArgs);
  		} catch (Exception e) {
  			throw new RuntimeException("Cannot start main class.", e);
  		}
  
  	}
  
  	/**
  	 * Transform a line into an array of arguments, taking "" as single
  	 * arguments. (nested \" are not supported)
  	 */
  	private static String[] readArgumentsFromLine(String lineOrig) {
  		String line = lineOrig.trim();// remove trailing spaces
  		List<String> args = new ArrayList<String>();
  		StringBuffer curr = new StringBuffer("");
  		boolean inQuote = false;
  		char[] arr = line.toCharArray();
  		for (int i = 0; i < arr.length; i++) {
  			char c = arr[i];
 			switch (c) {
 			case '\"':
 				inQuote = !inQuote;
 				break;
 			case ' ':
 				if (!inQuote) {// otherwise, no break: goes to default
 					if (curr.length() > 0) {
 						args.add(curr.toString());
 						curr = new StringBuffer("");
 					}
 					break;
 				}
 			default:
 				curr.append(c);
 				break;
 			}
 		}
 
 		// Add last arg
 		if (curr.length() > 0) {
 			args.add(curr.toString());
 			curr = null;
 		}
 
 		String[] res = new String[args.size()];
 		for (int i = 0; i < args.size(); i++) {
 			res[i] = args.get(i).toString();
 		}
 		return res;
 	}
 
 	public static String getProperty(String name, String defaultValue) {
 		final String value;
 		if (defaultValue != null)
 			value = System.getProperty(name, defaultValue);
 		else
 			value = System.getProperty(name);
 
 		if (value == null || value.equals(""))
 			return null;
 		else
 			return value;
 	}
 
 	public static String getProperty(String name) {
 		return getProperty(name, null);
 	}
 
 }