Copyright (c) 2000, 2011 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 Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2011 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 Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.core.search;

import java.io.IOException;

import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.OperationCanceledException;
import org.eclipse.core.runtime.SubMonitor;
import org.eclipse.jdt.core.search.*;
import org.eclipse.jdt.internal.core.JavaModelManager;
import org.eclipse.jdt.internal.core.index.FileIndexLocation;
import org.eclipse.jdt.internal.core.index.Index;
import org.eclipse.jdt.internal.core.index.IndexLocation;
import org.eclipse.jdt.internal.core.search.indexing.ReadWriteMonitor;
import org.eclipse.jdt.internal.core.search.matching.MatchLocator;
import org.eclipse.jdt.internal.core.search.processing.IJob;
import org.eclipse.jdt.internal.core.search.processing.JobManager;
import org.eclipse.jdt.internal.core.util.Util;

public class PatternSearchJob implements IJob {

protected SearchPattern pattern;
protected IJavaSearchScope scope;
protected SearchParticipant participant;
protected IndexQueryRequestor requestor;
protected boolean areIndexesReady;
protected long executionTime = 0;

public PatternSearchJob(SearchPattern pattern, SearchParticipant participant, IJavaSearchScope scope, IndexQueryRequestor requestor) {
	this.pattern = pattern;
	this.participant = participant;
	this.scope = scope;
	this.requestor = requestor;
}
@Override
public boolean belongsTo(String jobFamily) {
	return true;
}
@Override
public void cancel() {
	// search job is cancelled through progress
}
@Override
public void ensureReadyToRun() {
	if (!this.areIndexesReady)
		getIndexes(null/*progress*/); // may trigger some index recreation
}
@Override
public boolean execute(IProgressMonitor progressMonitor) {
	SubMonitor subMonitor = SubMonitor.convert(progressMonitor, 3);

	boolean isComplete = COMPLETE;
	this.executionTime = 0;
	Index[] indexes = getIndexes(subMonitor.split(1));
	try {
		int max = indexes.length;
		SubMonitor loopMonitor = subMonitor.split(2).setWorkRemaining(max);
		for (int i = 0; i < max; i++) {
			isComplete &= search(indexes[i], loopMonitor.split(1));
		}
		if (JobManager.VERBOSE)
			Util.verbose("-> execution time: " + this.executionTime + "ms - " + this);//$NON-NLS-1$//$NON-NLS-2$
		return isComplete;
	} finally {
		SubMonitor.done(progressMonitor);
	}
}
public Index[] getIndexes(IProgressMonitor progressMonitor) {
	// acquire the in-memory indexes on the fly
	IndexLocation[] indexLocations;
	int length;
	if (this.participant instanceof JavaSearchParticipant) {
		indexLocations = ((JavaSearchParticipant)this.participant).selectIndexURLs(this.pattern, this.scope);
		length = indexLocations.length;
	} else {
		IPath[] paths = this.participant.selectIndexes(this.pattern, this.scope);
		length = paths.length;
		indexLocations = new IndexLocation[paths.length];
		for (int i = 0, len = paths.length; i < len; i++) {
			indexLocations[i] = new FileIndexLocation(paths[i].toFile(), true);
		}
	}
	Index[] indexes = JavaModelManager.getIndexManager().getIndexes(indexLocations, progressMonitor);
	this.areIndexesReady = indexes.length == length;
	return indexes;
}

@Override
public boolean waitNeeded() {
	return true;
}
@Override
public String getJobFamily() {
	return ""; //$NON-NLS-1$
}
public boolean search(Index index, IProgressMonitor progressMonitor) {
	if (index == null) return COMPLETE;
	if (progressMonitor != null && progressMonitor.isCanceled()) throw new OperationCanceledException();
	ReadWriteMonitor monitor = index.monitor;
	if (monitor == null) return COMPLETE; // index got deleted since acquired
	try {
		monitor.enterRead(); // ask permission to read
		long start = System.currentTimeMillis();
		MatchLocator.findIndexMatches(this.pattern, index, this.requestor, this.participant, this.scope, progressMonitor);
		this.executionTime += System.currentTimeMillis() - start;
		return COMPLETE;
	} catch (IOException e) {
		if (e instanceof java.io.EOFException)
			e.printStackTrace();
		return FAILED;
	} finally {
		monitor.exitRead(); // finished reading
	}
}
@Override
public String toString() {
	return "searching " + this.pattern.toString(); //$NON-NLS-1$
}
}