/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *******************************************************************************/
package org.eclipse.dltk.ui.preferences;

import java.lang.reflect.InvocationTargetException;
import java.util.Map;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IWorkspaceRunnable;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.dltk.core.DLTKCore;
import org.eclipse.dltk.core.DLTKLanguageManager;
import org.eclipse.dltk.core.IBuildpathEntry;
import org.eclipse.dltk.core.IModelElement;
import org.eclipse.dltk.core.IScriptLanguageProvider;
import org.eclipse.dltk.core.IScriptProject;
import org.eclipse.dltk.internal.ui.actions.WorkbenchRunnableAdapter;
import org.eclipse.dltk.internal.ui.dialogs.StatusUtil;
import org.eclipse.dltk.ui.DLTKUIPlugin;
import org.eclipse.dltk.ui.util.ExceptionHandler;
import org.eclipse.dltk.ui.util.IStatusChangeListener;
import org.eclipse.dltk.ui.wizards.BuildpathsBlock;
import org.eclipse.dltk.utils.AdaptUtils;
import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.dialogs.IDialogSettings;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.dialogs.ProgressMonitorDialog;
import org.eclipse.jface.preference.IPreferencePageContainer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;
import org.eclipse.ui.dialogs.PropertyPage;
import org.eclipse.ui.preferences.IWorkbenchPreferenceContainer;

/**
 * Property page for configuring the DLTK build path
 */
public abstract class BuildPathsPropertyPage extends PropertyPage implements
		IStatusChangeListener, IScriptLanguageProvider {

	public static final String PROP_ID = "org.eclipse.dltk.ui.propertyPages.BuildPathsPropertyPage"; //$NON-NLS-1$

	private static final String PAGE_SETTINGS = "BuildPathsPropertyPage"; //$NON-NLS-1$
	protected static final String INDEX = "pageIndex"; //$NON-NLS-1$

	public static final Object DATA_ADD_ENTRY = "add_buildpath_entry"; //$NON-NLS-1$

	public static final Object DATA_REVEAL_ENTRY = "select_buildpath_entry"; //$NON-NLS-1$
	public static final Object DATA_REVEAL_ATTRIBUTE_KEY = "select_buildpath_attribute_key"; //$NON-NLS-1$

	public static final Object DATA_BLOCK = "block_until_buildpath_applied"; //$NON-NLS-1$

	private BuildpathsBlock fBuildPathsBlock;
	private boolean fBlockOnApply = false;

	@Override
	protected Control createContents(Composite parent) {
		// ensure the page has no special buttons
		noDefaultAndApplyButton();

		IProject project = getProject();
		Control result;
		if (project == null || !isValidProject(project)) {
			result = createWithoutScript(parent);
		} else if (!project.isOpen()) {
			result = createForClosedProject(parent);
		} else {
			result = createWith(parent, project);
		}
		Dialog.applyDialogFont(result);
		return result;
	}

	@Override
	public void createControl(Composite parent) {
		super.createControl(parent);
		// PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(),
		// IHelpContextIds.BUILD_PATH_PROPERTY_PAGE);
	}

	protected IDialogSettings getSettings() {
		IDialogSettings javaSettings = DLTKUIPlugin.getDefault()
				.getDialogSettings();
		IDialogSettings pageSettings = javaSettings.getSection(PAGE_SETTINGS);
		if (pageSettings == null) {
			pageSettings = javaSettings.addNewSection(PAGE_SETTINGS);
			pageSettings.put(INDEX, 3);
		}
		return pageSettings;
	}

	@Override
	public void setVisible(boolean visible) {
		if (fBuildPathsBlock != null) {
			if (!visible) {
				if (fBuildPathsBlock.hasChangesInDialog()) {
					String title = PreferencesMessages.BuildPathsPropertyPage_unsavedchanges_title;
					String message = PreferencesMessages.BuildPathsPropertyPage_unsavedchanges_message;
					String[] buttonLabels = new String[] {
							PreferencesMessages.BuildPathsPropertyPage_unsavedchanges_button_save,
							PreferencesMessages.BuildPathsPropertyPage_unsavedchanges_button_discard,
							PreferencesMessages.BuildPathsPropertyPage_unsavedchanges_button_ignore };
					MessageDialog dialog = new MessageDialog(getShell(), title,
							null, message, MessageDialog.QUESTION,
							buttonLabels, 0);
					int res = dialog.open();
					if (res == 0) {
						performOk();
					} else if (res == 1) {
						fBuildPathsBlock.init(DLTKCore.create(getProject()),
								null);
					} else {
						// keep unsaved
					}
				}
			} else {
				if (!fBuildPathsBlock.hasChangesInDialog()
						&& fBuildPathsBlock.hasChangesInBuildpathFile()) {
					fBuildPathsBlock.init(DLTKCore.create(getProject()), null);
				}
			}
		}
		super.setVisible(visible);
	}

	/*
	 * Content for valid projects.
	 */
	private Control createWith(Composite parent, IProject project) {
		IWorkbenchPreferenceContainer pageContainer = null;
		IPreferencePageContainer container = getContainer();
		if (container instanceof IWorkbenchPreferenceContainer) {
			pageContainer = (IWorkbenchPreferenceContainer) container;
		}

		fBuildPathsBlock = createBuildPathBlock(pageContainer);
		fBuildPathsBlock.init(DLTKCore.create(project), null);
		return fBuildPathsBlock.createControl(parent);
	}

	protected BuildpathsBlock createBuildPathBlock(
			IWorkbenchPreferenceContainer pageContainer) {
		return new BuildpathsBlock(this, getSettings().getInt(INDEX), false,
				pageContainer);
	}

	/*
	 * Content for non-script projects.
	 */
	private Control createWithoutScript(Composite parent) {
		Label label = new Label(parent, SWT.LEFT);
		label
				.setText(PreferencesMessages.BuildPathsPropertyPage_no_script_project_message);

		fBuildPathsBlock = null;
		setValid(true);
		return label;
	}

	/*
	 * Content for closed projects.
	 */
	private Control createForClosedProject(Composite parent) {
		Label label = new Label(parent, SWT.LEFT);
		label
				.setText(PreferencesMessages.BuildPathsPropertyPage_closed_project_message);

		fBuildPathsBlock = null;
		setValid(true);
		return label;
	}

	protected IProject getProject() {
		final IAdaptable adaptable = getElement();
		IProject project = AdaptUtils.getAdapter(adaptable, IProject.class);
		if (project != null) {
			return project;
		}
		final IModelElement elem = AdaptUtils.getAdapter(adaptable,
				IModelElement.class);
		if (elem instanceof IScriptProject) {
			return ((IScriptProject) elem).getProject();
		}
		return null;
	}

	protected boolean isValidProject(IProject proj) {
		return DLTKLanguageManager.hasScriptNature(proj);
	}

	@Override
	public boolean performOk() {
		if (fBuildPathsBlock != null) {
			getSettings().put(INDEX, fBuildPathsBlock.getPageIndex());
			if (fBuildPathsBlock.hasChangesInDialog()) {
				IWorkspaceRunnable runnable = monitor -> fBuildPathsBlock.configureScriptProject(monitor);
				WorkbenchRunnableAdapter op = new WorkbenchRunnableAdapter(
						runnable);
				if (fBlockOnApply) {
					try {
						new ProgressMonitorDialog(getShell()).run(true, true,
								op);
					} catch (InvocationTargetException e) {
						ExceptionHandler
								.handle(
										e,
										getShell(),
										PreferencesMessages.BuildPathsPropertyPage_error_title,
										PreferencesMessages.BuildPathsPropertyPage_error_message);
						return false;
					} catch (InterruptedException e) {
						return false;
					}
				} else {
					op
							.runAsUserJob(
									PreferencesMessages.BuildPathsPropertyPage_job_title,
									null);
				}
			}
		}
		return true;
	}

	@Override
	public void statusChanged(IStatus status) {
		setValid(!status.matches(IStatus.ERROR));
		StatusUtil.applyToStatusLine(this, status);
	}

	@Override
	public void applyData(Object data) {
		if (data instanceof Map) {
			Map map = (Map) data;
			Object selectedLibrary = map.get(DATA_REVEAL_ENTRY);
			if (selectedLibrary instanceof IBuildpathEntry) {
				IBuildpathEntry entry = (IBuildpathEntry) selectedLibrary;
				Object attr = map.get(DATA_REVEAL_ATTRIBUTE_KEY);
				String attributeKey = attr instanceof String ? (String) attr
						: null;
				if (fBuildPathsBlock != null) {
					fBuildPathsBlock.setElementToReveal(entry, attributeKey);
				}
			}
			Object entryToAdd = map.get(DATA_ADD_ENTRY);
			if (entryToAdd instanceof IBuildpathEntry) {
				if (fBuildPathsBlock != null) {
					fBuildPathsBlock.addElement((IBuildpathEntry) entryToAdd);
				}
			}
			fBlockOnApply = Boolean.TRUE.equals(map.get(DATA_BLOCK));
		}
	}

}