/*******************************************************************************
 * Copyright (c) 2003, 2015 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM - Initial API and implementation
 *******************************************************************************/
package org.eclipse.e4.ui.progress;

import java.lang.reflect.InvocationTargetException;

import org.eclipse.core.runtime.jobs.IJobManager;
import org.eclipse.core.runtime.jobs.ISchedulingRule;
import org.eclipse.core.runtime.jobs.Job;
import org.eclipse.core.runtime.jobs.ProgressProvider;
import org.eclipse.jface.operation.IRunnableContext;
import org.eclipse.jface.operation.IRunnableWithProgress;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Shell;

/**
 * The progress service is the primary interface to the workbench progress
 * support. It can be obtained from the workbench and then used to show progress
 * for both background operations and operations that run in the UI thread.
 * <p>
 * All methods on the progress service must be called from the UI thread.
 * </p>
 * <p>
 * This service can be acquired from your service locator:
 * </p>
 *
 * <pre>
 * IProgressService service = (IProgressService) getSite().getService(IProgressService.class);
 * </pre>
 * <ul>
 * <li>This service is available globally.</li>
 * </ul>
 * <p>
 * <strong>NOTE</strong> The progress service must be referenced at least once
 * before it will become the progress provider for the {@link IJobManager} in
 * the workbench. This connection is done lazily so that RCP applications will
 * not have to use the {@link IProgressService} as the {@link ProgressProvider}
 * to the jobs framework if they do not wish to reference it.
 * </p>
 *
 * @see IJobManager#setProgressProvider(org.eclipse.core.runtime.jobs.ProgressProvider)
 *
 * @since 3.0
 * @noimplement This interface is not intended to be implemented by clients.
 */
public interface IProgressService extends IRunnableContext {

	/**
	 * The time at which an operation becomes considered a long
	 * operation. Used to determine when the busy cursor will
	 * be replaced with a progress monitor.
	 * @return int
	 * @see IProgressService#busyCursorWhile(IRunnableWithProgress)
	 */
	public int getLongOperationTime();

	/**
	 * Register the ImageDescriptor to be the icon used for
	 * all jobs that belong to family within the workbench.
	 * @param icon ImageDescriptor that will be used when the job is being displayed
	 * @param family The family to associate with
	 * @see Job#belongsTo(Object)
	 */
	public void registerIconForFamily(ImageDescriptor icon, Object family);

	/**
	 * Runs the given operation in the UI thread using the given runnable context.
	 * The given scheduling rule, if any, will be acquired for the duration of the
	 * operation. If the rule is not available when this method is called, a
	 * progress dialog will be displayed that gives users control over the
	 * background processes that may be blocking the runnable from proceeding.
	 * <p>
	 * This method can act as a wrapper for uses of <code>IRunnableContext</code>
	 * where the <code>fork</code> parameter was <code>false</code>.
	 * </p>
	 * <p>
	 * Note: Running long operations in the UI thread is generally not recommended.
	 * This can result in the UI becoming unresponsive for the duration of the
	 * operation. Where possible, <code>busyCursorWhile</code> should be used
	 * instead.
	 * </p>
	 * <p>
	 * Modal dialogs should also be avoided in the runnable as there will already be
	 * a modal progress dialog open when this operation runs.
	 * </p>
	 *
	 * @see org.eclipse.jface.dialogs.Dialog
	 * @see org.eclipse.swt.SWT#APPLICATION_MODAL
	 *
	 * @param context  The runnable context to run the operation in
	 * @param runnable The operation to run
	 * @param rule     A scheduling rule, or <code>null</code>
	 * @throws InvocationTargetException wraps any exception or error which occurs
	 *                                   while running the runnable
	 * @throws InterruptedException      propagated by the context if the runnable
	 *                                   acknowledges cancelation by throwing this
	 *                                   exception.
	 *
	 */
	public void runInUI(IRunnableContext context,
			IRunnableWithProgress runnable, ISchedulingRule rule)
			throws InvocationTargetException, InterruptedException;

	/**
	 * Get the icon that has been registered for a Job by
	 * checking if the job belongs to any of the registered
	 * families.
	 * @param job job to get icon for
	 * @return Icon or <code>null</code> if there isn't one.
	 * @see IProgressService#registerIconForFamily(ImageDescriptor,Object)
	 */
	public Image getIconFor(Job job);

	/**
	 * Set the cursor to busy and run the runnable in a non-UI Thread.
	 * The calling thread will be blocked for the duration of the execution
	 * of the supplied runnable.
	 *
	 * After the cursor has been running for
	 * <code>getLongOperationTime()</code> replace it with
	 * a ProgressMonitorDialog so that the user may cancel.
	 * Do not open the ProgressMonitorDialog if there is already a modal
	 * dialog open.
	 *
	 * @param runnable The runnable to execute and show the progress for.
	 * @see IProgressService#getLongOperationTime
	 * @throws InvocationTargetException if executed operation failed
	 * @throws InterruptedException if operation is interrupted
	 */
	public void busyCursorWhile(IRunnableWithProgress runnable)
			throws InvocationTargetException, InterruptedException;

	/**
	 * This specialization of IRunnableContext#run(boolean, boolean,
	 * IRunnableWithProgress) might run the runnable asynchronously
	 * if <code>fork</code> is <code>true</code>.
	 *
	 * @since 3.2
	 */
	@Override
	public void run(boolean fork, boolean cancelable, IRunnableWithProgress runnable) throws InvocationTargetException, InterruptedException;

	/**
	 * Open a dialog on job when it starts to run and close it
	 * when the job is finished. Wait for ProgressManagerUtil#SHORT_OPERATION_TIME
	 * before opening the dialog. Do not open if it is already done or
	 * if the user has set a preference to always run in the background.
	 *
	 * Parent the dialog from the shell.
	 *
	 * @param shell The Shell to parent the dialog from or
	 * <code>null</code> if the active shell is to be used.
	 * @param job The Job that will be reported in the dialog. job
	 * must not be <code>null</code>.
	 */
	public void showInDialog(Shell shell, Job job);

}
