/*******************************************************************************
 * Copyright (c) 2000, 2009 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.ui.wizards;

import java.lang.reflect.InvocationTargetException;
import java.net.URI;

import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;

import org.eclipse.core.filesystem.URIUtil;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.OperationCanceledException;
import org.eclipse.core.runtime.SubProgressMonitor;

import org.eclipse.core.resources.IProject;

import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.operation.IRunnableWithProgress;

import org.eclipse.ui.PlatformUI;

import org.eclipse.jdt.core.IClasspathEntry;
import org.eclipse.jdt.core.IJavaProject;

import org.eclipse.jdt.internal.ui.IJavaHelpContextIds;
import org.eclipse.jdt.internal.ui.util.BusyIndicatorRunnableContext;
import org.eclipse.jdt.internal.ui.wizards.IStatusChangeListener;
import org.eclipse.jdt.internal.ui.wizards.NewWizardMessages;
import org.eclipse.jdt.internal.ui.wizards.buildpaths.BuildPathsBlock;

/**
 * Basic wizard page for creating new Java projects. This page can be used in
 * project creation wizards. The page shows UI to configure the project with a Java
 * build path and output location. On finish the page will also configure the Java nature.
 * <p>
 * This is a replacement for {@link NewJavaProjectWizardPage} with a cleaner API.
 * </p>
 * <p>
 * The pages used by the New Java Project wizard are {@link NewJavaProjectWizardPageOne} and
 * {@link NewJavaProjectWizardPageTwo}.
 * </p>
 * <p>
 * Clients may instantiate or subclass.
 * </p>
 *
 * @since 2.0
 */
public class JavaCapabilityConfigurationPage extends NewElementWizardPage {

    private static final String PAGE_NAME= "JavaCapabilityConfigurationPage"; //$NON-NLS-1$

    private IJavaProject fJavaProject;
    private BuildPathsBlock fBuildPathsBlock;

    /**
     * Creates a wizard page that can be used in a Java project creation wizard.
     * It contains UI to configure a the classpath and the output folder.
     *
     * <p>
     * After constructing, a call to {@link #init(IJavaProject, IPath, IClasspathEntry[], boolean)} is required.
     * </p>
     */
    public JavaCapabilityConfigurationPage() {
        super(PAGE_NAME);
        fJavaProject= null;

        setTitle(NewWizardMessages.JavaCapabilityConfigurationPage_title);
        setDescription(NewWizardMessages.JavaCapabilityConfigurationPage_description);
    }

    private BuildPathsBlock getBuildPathsBlock() {
        if (fBuildPathsBlock == null) {
            IStatusChangeListener listener= new IStatusChangeListener() {
                public void statusChanged(IStatus status) {
                    updateStatus(status);
                }
            };
            fBuildPathsBlock= new BuildPathsBlock(new BusyIndicatorRunnableContext(), listener, 0, useNewSourcePage(), null);
        }
        return fBuildPathsBlock;
    }

    /*
     * @see org.eclipse.jface.dialogs.DialogPage#dispose()
     * @since 3.3
     */
    public void dispose() {
        try {
            super.dispose();
        } finally {
            if (fBuildPathsBlock != null) {
                fBuildPathsBlock.dispose();
                fBuildPathsBlock= null;
            }
        }
    }

    /**
     * Clients can override this method to choose if the new source page is used. The new source page
     * requires that the project is already created as Java project. The page will directly manipulate the classpath.
     * By default <code>false</code> is returned.
     * @return Returns <code>true</code> if the new source page should be used.
     * @since 3.1
     */
    protected boolean useNewSourcePage() {
        return false;
    }

    /**
     * Initializes the page with the project and default classpath.
     * <p>
     * The default classpath entries must correspond the given project.
     * </p>
     * <p>
     * The caller of this method is responsible for creating the underlying project. The page will create the output,
     * source and library folders if required.
     * </p>
     * <p>
     * The project does not have to exist at the time of initialization, but must exist when executing the runnable
     * obtained by <code>getRunnable()</code>.
     * </p>
     * @param jproject The Java project.
     * @param defaultOutputLocation The default classpath entries or <code>null</code> to let the page choose the default
     * @param defaultEntries The folder to be taken as the default output path or <code>null</code> to let the page choose the default
     * @param defaultsOverrideExistingClasspath If set to <code>true</code>, an existing '.classpath' file is ignored. If set to <code>false</code>
     * the given default classpath and output location is only used if no '.classpath' exists.
     */
    public void init(IJavaProject jproject, IPath defaultOutputLocation, IClasspathEntry[] defaultEntries, boolean defaultsOverrideExistingClasspath) {
        if (!defaultsOverrideExistingClasspath && jproject.exists() && jproject.getProject().getFile(".classpath").exists()) { //$NON-NLS-1$
            defaultOutputLocation= null;
            defaultEntries= null;
        }
        getBuildPathsBlock().init(jproject, defaultOutputLocation, defaultEntries);
        fJavaProject= jproject;
    }

    /* (non-Javadoc)
     * @see WizardPage#createControl
     */
    public void createControl(Composite parent) {
        Composite composite= new Composite(parent, SWT.NONE);
        composite.setFont(parent.getFont());
        composite.setLayout(new GridLayout(1, false));
        Control control= getBuildPathsBlock().createControl(composite);
        control.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
        Dialog.applyDialogFont(composite);
        PlatformUI.getWorkbench().getHelpSystem().setHelp(composite, IJavaHelpContextIds.NEW_JAVAPROJECT_WIZARD_PAGE);
        setControl(composite);
    }

    /**
     * Returns the currently configured output location. Note that the returned path
     * might not be a valid path.
     *
     * @return the currently configured output location
     */
    public IPath getOutputLocation() {
        return getBuildPathsBlock().getOutputLocation();
    }

    /**
     * Returns the currently configured classpath. Note that the classpath might
     * not be valid.
     *
     * @return the currently configured classpath
     */
    public IClasspathEntry[] getRawClassPath() {
        return getBuildPathsBlock().getRawClassPath();
    }

    /**
     * Returns the Java project that was passed in {@link #init(IJavaProject, IPath, IClasspathEntry[], boolean)} or <code>null</code> if the
     * page has not been initialized yet.
     *
     * @return the managed Java project or <code>null</code>
     */
    public IJavaProject getJavaProject() {
        return fJavaProject;
    }


    /**
     * Returns the runnable that will create the Java project or <code>null</code> if the page has
     * not been initialized. The runnable sets the project's classpath and output location to the values
     * configured in the page and adds the Java nature if not set yet. The method requires that the
     * project is created and opened.
     *
     * @return the runnable that creates the new Java project
     */
    public IRunnableWithProgress getRunnable() {
        if (getJavaProject() != null) {
            return new IRunnableWithProgress() {
                public void run(IProgressMonitor monitor) throws InvocationTargetException, InterruptedException {
                    try {
                        configureJavaProject(monitor);
                    } catch (CoreException e) {
                        throw new InvocationTargetException(e);
                    }
                }
            };
        }
        return null;
    }

    /**
     * Helper method to create and open a IProject. The project location
     * is configured. No natures are added.
     *
     * @param project The handle of the project to create.
     * @param locationPath The location of the project <code>null</code> to create the project in the workspace
     * @param monitor a progress monitor to report progress or <code>null</code> if
     *  progress reporting is not desired
     * @throws CoreException if the project couldn't be created
     * @since 2.1
     * @deprecated use {@link #createProject(IProject, URI, IProgressMonitor)} instead.
     */
    public static void createProject(IProject project, IPath locationPath, IProgressMonitor monitor) throws CoreException {
        createProject(project, locationPath != null ? URIUtil.toURI(locationPath) : null, monitor);
    }

    /**
     * Helper method to create and open a IProject. The project location
     * is configured. No natures are added.
     *
     * @param project The handle of the project to create.
     * @param locationURI The location of the project or <code>null</code> to create the project in the workspace
     * @param monitor a progress monitor to report progress or <code>null</code> if
     *  progress reporting is not desired
     * @throws CoreException if the project couldn't be created
     * @see org.eclipse.core.resources.IProjectDescription#setLocationURI(java.net.URI)
     * @since 3.2
     */
    public static void createProject(IProject project, URI locationURI, IProgressMonitor monitor) throws CoreException {
        BuildPathsBlock.createProject(project, locationURI, monitor);
    }

    /**
     * Adds the Java nature to the project (if not set yet) and configures the build classpath.
     *
     * @param monitor a progress monitor to report progress or <code>null</code> if
     * progress reporting is not desired
     * @throws CoreException Thrown when the configuring the Java project failed.
     * @throws InterruptedException Thrown when the operation has been canceled.
     */
    public void configureJavaProject(IProgressMonitor monitor) throws CoreException, InterruptedException {
        configureJavaProject(null, monitor);
    }
    
    /**
     * Adds the Java nature to the project (if not set yet) and configures the build classpath.
     *
     * @param newProjectCompliance compliance to set for a new project, can be <code>null</code>
     * @param monitor a progress monitor to report progress or <code>null</code> if
     * progress reporting is not desired
     * @throws CoreException Thrown when the configuring the Java project failed.
     * @throws InterruptedException Thrown when the operation has been canceled.
     * @since 3.5
     */
    public void configureJavaProject(String newProjectCompliance, IProgressMonitor monitor) throws CoreException, InterruptedException {
        if (monitor == null) {
            monitor= new NullProgressMonitor();
        }

        int nSteps= 6;
        monitor.beginTask(NewWizardMessages.JavaCapabilityConfigurationPage_op_desc_java, nSteps);

        try {
            IProject project= getJavaProject().getProject();
            BuildPathsBlock.addJavaNature(project, new SubProgressMonitor(monitor, 1));
            getBuildPathsBlock().configureJavaProject(newProjectCompliance, new SubProgressMonitor(monitor, 5));
        } catch (OperationCanceledException e) {
            throw new InterruptedException();
        } finally {
            monitor.done();
        }
    }

    /**
     * Transfers the focus into this page.
     *
     * @since 3.3
     */
    protected void setFocus() {
        getBuildPathsBlock().setFocus();
    }
}