/*******************************************************************************
 * Copyright (c) 2004, 2006 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.ant.internal.core;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.variables.IStringVariableManager;
import org.eclipse.core.variables.VariablesPlugin;
import org.osgi.framework.BundleContext;

public class AntCoreUtil {
    
    private static BundleContext fgContext= null;
    
    public static void setBundleContext(BundleContext context) {
        fgContext= context;
    }
    
    public static BundleContext getBundleContext() {
        return fgContext;
    }
    
    /*
	 * Helper method to ensure an array is converted into an ArrayList.
	 */
	public static ArrayList getArrayList(String[] args) {
		if (args == null) {
			return null;
		}
		// We could be using Arrays.asList() here, but it does not specify
		// what kind of list it will return. We need a list that
		// implements the method List.remove(Object) and ArrayList does.
		ArrayList result = new ArrayList(args.length);
		for (int i = 0; i < args.length; i++) {
			result.add(args[i]);
		}
		return result;
	}
	
	/*
	 * From a command line list, get the argument for the given parameter.
	 * The parameter and its argument are removed from the list.
	 * 
	 * @return <code>null</code> if the parameter is not found 
	 * 			or an empty String if no arguments are found
	 */
	public static String getArgument(List commands, String param) {
		if (commands == null) {
			return null;
		}
		int index = commands.indexOf(param);
		if (index == -1) {
			return null;
		}
		commands.remove(index);
		if (index == commands.size()) {// if this is the last command
			return ""; //$NON-NLS-1$
		}
		
		String command = (String) commands.get(index);
		if (command.startsWith("-")) { //new parameter //$NON-NLS-1$
			return ""; //$NON-NLS-1$
		}
		commands.remove(index);
		return command;
	}
	
	public static void processMinusDProperties(List commands, Map userProperties) {
	    Iterator iter= commands.iterator();
	    while (iter.hasNext()) {
            String arg = (String) iter.next();
			if (arg.startsWith("-D")) { //$NON-NLS-1$
				String name = arg.substring(2, arg.length());
				String value = null;
				int posEq = name.indexOf("="); //$NON-NLS-1$
				if (posEq == 0) {
					value= name.substring(1);
					name= ""; //$NON-NLS-1$
				} else if (posEq > 0 && posEq != name.length() - 1) {
					value = name.substring(posEq + 1).trim();
					name = name.substring(0, posEq);
				}
				
				if (value == null) {
					//the user has specified something like "-Debug"
					continue;
				}
	
				userProperties.put(name, value);
				iter.remove();
			}
		}
	}
	
	public static File getFileRelativeToBaseDir(String fileName, String base, String buildFileLocation) {
		IPath path= new Path(fileName);
		if (!path.isAbsolute()) {
			if (base != null) {
				File baseDir= new File(base);
				//relative to the base dir
				path= new Path(baseDir.getAbsolutePath()); 
			} else {
				//relative to the build file location
				path= new Path(buildFileLocation);
				path= path.removeLastSegments(1);
			}
			path= path.addTrailingSeparator();
			path= path.append(fileName);
		}
		
		return path.toFile();
	}
	
	/**
	 * Returns a list of Properties contained in the list of fileNames.
	 */
	public static List loadPropertyFiles(List fileNames, String base, String buildFileLocation) throws IOException {
	    List allProperties= new ArrayList(fileNames.size());
		for (int i = 0; i < fileNames.size(); i++) {
			String filename = (String) fileNames.get(i);
           	File file= getFileRelativeToBaseDir(filename, base, buildFileLocation);
            Properties props = new Properties();
            FileInputStream fis = null;
            try {
                fis = new FileInputStream(file);
                props.load(fis);
            } finally {
                if (fis != null) {
                    try {
                        fis.close();
                    } catch (IOException e){
                    }
                }
            }
            Enumeration propertyNames = props.propertyNames();
            while (propertyNames.hasMoreElements()) {
                String name = (String) propertyNames.nextElement();
                
                String value= props.getProperty(name);
                props.remove(name);
                IStringVariableManager stringVariableManager = VariablesPlugin.getDefault().getStringVariableManager();
				try {
					name= stringVariableManager.performStringSubstitution(name);
					value= stringVariableManager.performStringSubstitution(value);
				} catch (CoreException e) {
				}
                props.setProperty(name, value);
            }
            allProperties.add(props);
        }
		return allProperties;
	}
}