/*******************************************************************************
 * Copyright (c) 2005, 2008 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
 *     Les Jones <lesojones@gmail.com> - Bug 195433
 *******************************************************************************/
package org.eclipse.pde.internal.ui.launcher;

import java.util.ArrayList;
import org.eclipse.core.runtime.*;
import org.eclipse.debug.core.ILaunchConfiguration;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.launching.*;
import org.eclipse.jdt.launching.environments.IExecutionEnvironment;
import org.eclipse.jdt.launching.environments.IExecutionEnvironmentsManager;
import org.eclipse.osgi.util.NLS;
import org.eclipse.pde.internal.ui.PDEUIMessages;
import org.eclipse.pde.ui.launcher.IPDELauncherConstants;

public class VMHelper {

	public static IVMInstall[] getAllVMInstances() {
		ArrayList res = new ArrayList();
		IVMInstallType[] types = JavaRuntime.getVMInstallTypes();
		for (int i = 0; i < types.length; i++) {
			IVMInstall[] installs = types[i].getVMInstalls();
			for (int k = 0; k < installs.length; k++) {
				res.add(installs[k]);
			}
		}
		return (IVMInstall[]) res.toArray(new IVMInstall[res.size()]);
	}

	public static String[] getVMInstallNames() {
		IVMInstall[] installs = getAllVMInstances();
		String[] names = new String[installs.length];
		for (int i = 0; i < installs.length; i++) {
			names[i] = installs[i].getName();
		}
		return names;
	}

	/**
	 * Get the default VMInstall name using the available info in the config,
	 * using the JavaProject if available.
	 * 
	 * @param configuration
	 *            Launch configuration to check
	 * @return name of the VMInstall
	 * @throws CoreException
	 *             thrown if there's a problem getting the VM name
	 */
	public static String getDefaultVMInstallName(ILaunchConfiguration configuration) throws CoreException {
		IJavaProject javaProject = JavaRuntime.getJavaProject(configuration);
		IVMInstall vmInstall = null;
		if (javaProject != null) {
			vmInstall = JavaRuntime.getVMInstall(javaProject);
		}

		if (vmInstall != null) {
			return vmInstall.getName();
		}

		return getDefaultVMInstallName();
	}

	/**
	 * Returns the name of the default VM Install from Java Runtime.
	 * Will return an empty string if no default VM has been set.
	 * @return name of the default vm install, possibly an empty string
	 */
	public static String getDefaultVMInstallName() {
		IVMInstall install = JavaRuntime.getDefaultVMInstall();
		if (install != null)
			return install.getName();
		return ""; //$NON-NLS-1$
	}

	public static String getDefaultVMInstallLocation() {
		IVMInstall install = JavaRuntime.getDefaultVMInstall();
		if (install != null)
			return install.getInstallLocation().getAbsolutePath();
		return null;
	}

	public static IVMInstall getVMInstall(ILaunchConfiguration configuration) throws CoreException {
		String jre = configuration.getAttribute(IJavaLaunchConfigurationConstants.ATTR_JRE_CONTAINER_PATH, (String) null);
		IVMInstall vm = null;
		if (jre == null) {
			String name = configuration.getAttribute(IPDELauncherConstants.VMINSTALL, (String) null);
			if (name == null) {
				name = getDefaultVMInstallName(configuration);
			}
			vm = getVMInstall(name);
			if (vm == null) {
				throw new CoreException(LauncherUtils.createErrorStatus(NLS.bind(PDEUIMessages.WorkbenchLauncherConfigurationDelegate_noJRE, name)));
			}
		} else {
			IPath jrePath = Path.fromPortableString(jre);
			vm = JavaRuntime.getVMInstall(jrePath);
			if (vm == null) {
				String id = JavaRuntime.getExecutionEnvironmentId(jrePath);
				if (id == null) {
					String name = JavaRuntime.getVMInstallName(jrePath);
					throw new CoreException(LauncherUtils.createErrorStatus(NLS.bind(PDEUIMessages.WorkbenchLauncherConfigurationDelegate_noJRE, name)));
				}
				throw new CoreException(LauncherUtils.createErrorStatus(NLS.bind(PDEUIMessages.VMHelper_cannotFindExecEnv, id)));
			}
		}
		return vm;
	}

	public static IVMInstall getVMInstall(String name) {
		if (name != null) {
			IVMInstall[] installs = getAllVMInstances();
			for (int i = 0; i < installs.length; i++) {
				if (installs[i].getName().equals(name))
					return installs[i];
			}
		}
		return JavaRuntime.getDefaultVMInstall();
	}

	public static IVMInstall createLauncher(ILaunchConfiguration configuration) throws CoreException {
		IVMInstall launcher = getVMInstall(configuration);
		if (!launcher.getInstallLocation().exists())
			throw new CoreException(LauncherUtils.createErrorStatus(PDEUIMessages.WorkbenchLauncherConfigurationDelegate_jrePathNotFound));
		return launcher;
	}

	public static IExecutionEnvironment[] getExecutionEnvironments() {
		IExecutionEnvironmentsManager manager = JavaRuntime.getExecutionEnvironmentsManager();
		return manager.getExecutionEnvironments();
	}

	public static IExecutionEnvironment getExecutionEnvironment(String id) {
		IExecutionEnvironmentsManager manager = JavaRuntime.getExecutionEnvironmentsManager();
		return manager.getEnvironment(id);
	}

	public static String getVMInstallName(IExecutionEnvironment ee) throws CoreException {
		IPath containerPath = JavaRuntime.newJREContainerPath(ee);
		IVMInstall vmi = JavaRuntime.getVMInstall(containerPath);
		if (vmi == null)
			throw new CoreException(LauncherUtils.createErrorStatus(NLS.bind(PDEUIMessages.VMHelper_noJreForExecEnv, ee.getId())));
		return vmi.getName();
	}
}