/*******************************************************************************
 * Copyright (c) 2000, 2005 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.jdt.internal.launching;


import java.io.File;
import java.text.DateFormat;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.SubProgressMonitor;
import org.eclipse.debug.core.ILaunch;
import org.eclipse.debug.core.model.IProcess;
import org.eclipse.jdt.launching.AbstractVMRunner;
import org.eclipse.jdt.launching.IJavaLaunchConfigurationConstants;
import org.eclipse.jdt.launching.IVMInstall;
import org.eclipse.jdt.launching.VMRunnerConfiguration;

public class StandardVMRunner extends AbstractVMRunner {
	protected IVMInstall fVMInstance;

	public StandardVMRunner(IVMInstall vmInstance) {
		fVMInstance= vmInstance;
	}
	
	protected String renderDebugTarget(String classToRun, int host) {
		String format= LaunchingMessages.StandardVMRunner__0__at_localhost__1__1; 
		return MessageFormat.format(format, new String[] { classToRun, String.valueOf(host) });
	}

	public static String renderProcessLabel(String[] commandLine) {
		String format= LaunchingMessages.StandardVMRunner__0____1___2; 
		String timestamp= DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.MEDIUM).format(new Date(System.currentTimeMillis()));
		return MessageFormat.format(format, new String[] { commandLine[0], timestamp });
	}
	
	protected static String renderCommandLine(String[] commandLine) {
		if (commandLine.length < 1)
			return ""; //$NON-NLS-1$
		StringBuffer buf= new StringBuffer();
		for (int i= 0; i < commandLine.length; i++) {
			buf.append(' ');
			char[] characters= commandLine[i].toCharArray();
			StringBuffer command= new StringBuffer();
			boolean containsSpace= false;
			for (int j = 0; j < characters.length; j++) {
				char character= characters[j];
				if (character == '\"') {
					command.append('\\');
				} else if (character == ' ') {
					containsSpace = true;
				}
				command.append(character);
			}
			if (containsSpace) {
				buf.append('\"');
				buf.append(command.toString());
				buf.append('\"');
			} else {
				buf.append(command.toString());
			}
		}	
		return buf.toString();
	}	
	
	protected void addArguments(String[] args, List v) {
		if (args == null) {
			return;
		}
		for (int i= 0; i < args.length; i++) {
			v.add(args[i]);
		}
	}
	
	/**
	 * Returns the working directory to use for the launched VM,
	 * or <code>null</code> if the working directory is to be inherited
	 * from the current process.
	 * 
	 * @return the working directory to use
	 * @exception CoreException if the working directory specified by
	 *  the configuration does not exist or is not a directory
	 */	
	protected File getWorkingDir(VMRunnerConfiguration config) throws CoreException {
		String path = config.getWorkingDirectory();
		if (path == null) {
			return null;
		}
		File dir = new File(path);
		if (!dir.isDirectory()) {
			abort(MessageFormat.format(LaunchingMessages.StandardVMRunner_Specified_working_directory_does_not_exist_or_is_not_a_directory___0__3, new String[] {path}), null, IJavaLaunchConfigurationConstants.ERR_WORKING_DIRECTORY_DOES_NOT_EXIST); 
		}
		return dir;
	}
	
	/**
	 * @see VMRunner#getPluginIdentifier()
	 */
	protected String getPluginIdentifier() {
		return LaunchingPlugin.getUniqueIdentifier();
	}
	
	/**
	 * Construct and return a String containing the full path of a java executable
	 * command such as 'java' or 'javaw.exe'.  If the configuration specifies an
	 * explicit executable, that is used.
	 * 
	 * @return full path to java executable
	 * @exception CoreException if unable to locate an executeable
	 */
	protected String constructProgramString(VMRunnerConfiguration config) throws CoreException {

		// Look for the user-specified java executable command
		String command= null;
		Map map= config.getVMSpecificAttributesMap();
		if (map != null) {
			command = (String)map.get(IJavaLaunchConfigurationConstants.ATTR_JAVA_COMMAND);
		}
		
		// If no java command was specified, use default executable
		if (command == null) {
			File exe = StandardVMType.findJavaExecutable(fVMInstance.getInstallLocation());
			if (exe == null) {
				abort(MessageFormat.format(LaunchingMessages.StandardVMRunner_Unable_to_locate_executable_for__0__1, new String[]{fVMInstance.getName()}), null, IJavaLaunchConfigurationConstants.ERR_INTERNAL_ERROR); 
			}
			return exe.getAbsolutePath();
		}
				
		// Build the path to the java executable.  First try 'bin', and if that
		// doesn't exist, try 'jre/bin'
		String installLocation = fVMInstance.getInstallLocation().getAbsolutePath() + File.separatorChar;
		File exe = new File(installLocation + "bin" + File.separatorChar + command); //$NON-NLS-1$ 		
		if (fileExists(exe)){
			return exe.getAbsolutePath();
		}
		exe = new File(exe.getAbsolutePath() + ".exe"); //$NON-NLS-1$
		if (fileExists(exe)){
			return exe.getAbsolutePath();
		}
		exe = new File(installLocation + "jre" + File.separatorChar + "bin" + File.separatorChar + command); //$NON-NLS-1$ //$NON-NLS-2$
		if (fileExists(exe)) {
			return exe.getAbsolutePath(); 
		}
		exe = new File(exe.getAbsolutePath() + ".exe"); //$NON-NLS-1$
		if (fileExists(exe)) {
			return exe.getAbsolutePath(); 
		}		

		
		// not found
		abort(MessageFormat.format(LaunchingMessages.StandardVMRunner_Specified_executable__0__does_not_exist_for__1__4, new String[]{command, fVMInstance.getName()}), null, IJavaLaunchConfigurationConstants.ERR_INTERNAL_ERROR); 
		// NOTE: an exception will be thrown - null cannot be returned
		return null;		
	}	
	
	protected boolean fileExists(File file) {
		return file.exists() && file.isFile();
	}

	protected String convertClassPath(String[] cp) {
		int pathCount= 0;
		StringBuffer buf= new StringBuffer();
		if (cp.length == 0) {
			return "";    //$NON-NLS-1$
		}
		for (int i= 0; i < cp.length; i++) {
			if (pathCount > 0) {
				buf.append(File.pathSeparator);
			}
			buf.append(cp[i]);
			pathCount++;
		}
		return buf.toString();
	}


	/* (non-Javadoc)
	 * @see org.eclipse.jdt.launching.IVMRunner#run(org.eclipse.jdt.launching.VMRunnerConfiguration, org.eclipse.debug.core.ILaunch, org.eclipse.core.runtime.IProgressMonitor)
	 */
	public void run(VMRunnerConfiguration config, ILaunch launch, IProgressMonitor monitor) throws CoreException {

		if (monitor == null) {
			monitor = new NullProgressMonitor();
		}
		
		IProgressMonitor subMonitor = new SubProgressMonitor(monitor, 1);
		subMonitor.beginTask(LaunchingMessages.StandardVMRunner_Launching_VM____1, 2); 
		subMonitor.subTask(LaunchingMessages.StandardVMRunner_Constructing_command_line____2); 
		
		String program= constructProgramString(config);
		
		List arguments= new ArrayList();
		arguments.add(program);
				
		// VM args are the first thing after the java program so that users can specify
		// options like '-client' & '-server' which are required to be the first option
		String[] allVMArgs = combineVmArgs(config, fVMInstance);
		addArguments(allVMArgs, arguments);
		
		addBootClassPathArguments(arguments, config);
		
		String[] cp= config.getClassPath();
		if (cp.length > 0) {
			arguments.add("-classpath"); //$NON-NLS-1$
			arguments.add(convertClassPath(cp));
		}
		arguments.add(config.getClassToLaunch());
		
		String[] programArgs= config.getProgramArguments();
		addArguments(programArgs, arguments);
				
		String[] cmdLine= new String[arguments.size()];
		arguments.toArray(cmdLine);
		
		String[] envp= config.getEnvironment();
		
		subMonitor.worked(1);

		// check for cancellation
		if (monitor.isCanceled()) {
			return;
		}
		
		subMonitor.subTask(LaunchingMessages.StandardVMRunner_Starting_virtual_machine____3); 
		Process p= null;
		File workingDir = getWorkingDir(config);
		p= exec(cmdLine, workingDir, envp);
		if (p == null) {
			return;
		}
		
		// check for cancellation
		if (monitor.isCanceled()) {
			p.destroy();
			return;
		}		
		
		IProcess process= newProcess(launch, p, renderProcessLabel(cmdLine), getDefaultProcessMap());
		process.setAttribute(IProcess.ATTR_CMDLINE, renderCommandLine(cmdLine));
		subMonitor.worked(1);
		subMonitor.done();
	}

	protected void addBootClassPathArguments(List arguments, VMRunnerConfiguration config) {
		String[] prependBootCP= null;
		String[] bootCP= null;
		String[] appendBootCP= null;
		Map map = config.getVMSpecificAttributesMap();
		if (map != null) {
			prependBootCP= (String[]) map.get(IJavaLaunchConfigurationConstants.ATTR_BOOTPATH_PREPEND);
			bootCP= (String[]) map.get(IJavaLaunchConfigurationConstants.ATTR_BOOTPATH);
			appendBootCP= (String[]) map.get(IJavaLaunchConfigurationConstants.ATTR_BOOTPATH_APPEND);
		}
		if (prependBootCP == null && bootCP == null && appendBootCP == null) {
			// use old single attribute instead of new attributes if not specified
			bootCP = config.getBootClassPath();
		}
		if (prependBootCP != null) {
			arguments.add("-Xbootclasspath/p:" + convertClassPath(prependBootCP)); //$NON-NLS-1$
		}
		if (bootCP != null) {
			if (bootCP.length > 0) {
				arguments.add("-Xbootclasspath:" + convertClassPath(bootCP)); //$NON-NLS-1$
			}
		}
		if (appendBootCP != null) {
			arguments.add("-Xbootclasspath/a:" + convertClassPath(appendBootCP)); //$NON-NLS-1$
		}
	}

}