Copyright (c) 2000, 2019 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
    Microsoft Corporation - copied to jdt.core.manipulation
/*******************************************************************************
 * Copyright (c) 2000, 2019 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
 *     Microsoft Corporation - copied to jdt.core.manipulation
 *******************************************************************************/
package org.eclipse.jdt.internal.corext.dom.fragments;

import org.eclipse.core.runtime.Assert;

import org.eclipse.jdt.core.IBuffer;
import org.eclipse.jdt.core.ISourceRange;
import org.eclipse.jdt.core.ToolFactory;
import org.eclipse.jdt.core.compiler.IScanner;
import org.eclipse.jdt.core.compiler.ITerminalSymbols;
import org.eclipse.jdt.core.compiler.InvalidInputException;
import org.eclipse.jdt.core.dom.ASTNode;

import org.eclipse.jdt.internal.corext.SourceRangeFactory;


This class houses a collection of static methods which do not refer to,
or otherwise depend on, other classes in this package.  Each
package-visible method is called by more than one other class in this
package.  Since they do not depend on other classes in this package,
they could be moved to some less specialized package.
/**
 * This class houses a collection of static methods which do not refer to,
 * or otherwise depend on, other classes in this package.  Each
 * package-visible method is called by more than one other class in this
 * package.  Since they do not depend on other classes in this package,
 * they could be moved to some less specialized package.
 */
class Util {
	static boolean rangeIncludesNonWhitespaceOutsideRange(ISourceRange selection, ISourceRange nodes, IBuffer buffer) {
		if (!covers(selection, nodes))
			return false;

		//TODO: skip leading comments. Consider that leading line comment must be followed by newline!
		if(!isJustWhitespace(selection.getOffset(), nodes.getOffset(), buffer))
			return true;
		if(!isJustWhitespaceOrComment(nodes.getOffset() + nodes.getLength(), selection.getOffset() + selection.getLength(), buffer))
			return true;
		return false;
	}
	private static boolean isJustWhitespace(int start, int end, IBuffer buffer) {
		if (start == end)
			return true;
		Assert.isTrue(start <= end);
		return 0 == buffer.getText(start, end - start).trim().length();
	}
	private static boolean isJustWhitespaceOrComment(int start, int end, IBuffer buffer) {
		if (start == end)
			return true;
		Assert.isTrue(start <= end);
		String trimmedText= buffer.getText(start, end - start).trim();
		if (0 == trimmedText.length()) {
			return true;
		} else {
			IScanner scanner= ToolFactory.createScanner(false, false, false, null);
			scanner.setSource(trimmedText.toCharArray());
			try {
				return scanner.getNextToken() == ITerminalSymbols.TokenNameEOF;
			} catch (InvalidInputException e) {
				return false;
			}
		}
	}

	public static int getEndExclusive(ISourceRange sourceRange) {
		return sourceRange.getOffset() + sourceRange.getLength();
	}

	public static int getEndInclusive(ISourceRange sourceRange) {
		return getEndExclusive(sourceRange) - 1;
	}

	public static boolean covers(ISourceRange sourceRange, ASTNode astNode) {
		return covers(sourceRange, SourceRangeFactory.create(astNode));
	}

	public static boolean covers(ISourceRange thisRange, ISourceRange otherRange) {
		return thisRange.getOffset() <= otherRange.getOffset()
				&& getEndInclusive(thisRange) >= getEndInclusive(otherRange);
	}

}