/*******************************************************************************
 * Copyright (c) 2008, 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.ui.search;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

import org.eclipse.core.runtime.IAdaptable;

import org.eclipse.core.resources.IFile;

import org.eclipse.ui.IEditorPart;

import org.eclipse.search.ui.text.AbstractTextSearchResult;
import org.eclipse.search.ui.text.IEditorMatchAdapter;
import org.eclipse.search.ui.text.IFileMatchAdapter;
import org.eclipse.search.ui.text.Match;

import org.eclipse.jdt.core.IClassFile;
import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IParent;
import org.eclipse.jdt.core.JavaModelException;

public abstract class AbstractJavaSearchResult extends AbstractTextSearchResult implements IEditorMatchAdapter, IFileMatchAdapter {

	protected static final Match[] NO_MATCHES= new Match[0];

	public AbstractJavaSearchResult() {
	}

	@Override
	public Match[] computeContainedMatches(AbstractTextSearchResult result, IEditorPart editor) {
		return computeContainedMatches(editor.getEditorInput());
	}

	@Override
	public Match[] computeContainedMatches(AbstractTextSearchResult result, IFile file) {
		return computeContainedMatches(file);
	}

	private Match[] computeContainedMatches(IAdaptable adaptable) {
		IJavaElement javaElement= adaptable.getAdapter(IJavaElement.class);
		Set<Match> matches= new HashSet<>();
		if (javaElement != null) {
			collectMatches(matches, javaElement);
		}
		IFile file= adaptable.getAdapter(IFile.class);
		if (file != null) {
			collectMatches(matches, file);
		}
		if (!matches.isEmpty()) {
			return matches.toArray(new Match[matches.size()]);
		}
		return NO_MATCHES;
	}

	private void collectMatches(Set<Match> matches, IFile element) {
		Match[] m= getMatches(element);
		if (m.length != 0) {
			matches.addAll(Arrays.asList(m));
		}
	}

	private void collectMatches(Set<Match> matches, IJavaElement element) {
		Match[] m= getMatches(element);
		if (m.length != 0) {
			matches.addAll(Arrays.asList(m));
		}
		if (element instanceof IParent) {
			IParent parent= (IParent) element;
			try {
				IJavaElement[] children= parent.getChildren();
				for (int i= 0; i < children.length; i++) {
					collectMatches(matches, children[i]);
				}
			} catch (JavaModelException e) {
				// we will not be tracking these results
			}
		}
	}
	@Override
	public IFile getFile(Object element) {
		if (element instanceof IJavaElement) {
			IJavaElement javaElement= (IJavaElement) element;
			ICompilationUnit cu= (ICompilationUnit) javaElement.getAncestor(IJavaElement.COMPILATION_UNIT);
			if (cu != null) {
				return (IFile) cu.getResource();
			} else {
				IClassFile cf= (IClassFile) javaElement.getAncestor(IJavaElement.CLASS_FILE);
				if (cf != null)
					return (IFile) cf.getResource();
			}
			return null;
		}
		if (element instanceof IFile)
			return (IFile) element;
		return null;
	}

	@Override
	public boolean isShownInEditor(Match match, IEditorPart editor) {
		Object element= match.getElement();
		if (element instanceof IJavaElement) {
			element= ((IJavaElement) element).getOpenable(); // class file or compilation unit
			return element != null && element.equals(editor.getEditorInput().getAdapter(IJavaElement.class));
		} else if (element instanceof IFile) {
			return element.equals(editor.getEditorInput().getAdapter(IFile.class));
		}
		return false;
	}

	@Override
	public IFileMatchAdapter getFileMatchAdapter() {
		return this;
	}

	@Override
	public IEditorMatchAdapter getEditorMatchAdapter() {
		return this;
	}

}