////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2015 the original author or authors.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
////////////////////////////////////////////////////////////////////////////////

package edu.cmu.cs.vbc.prog.checkstyle.checks.whitespace;

import edu.cmu.cs.vbc.prog.checkstyle.api.DetailAST;
import edu.cmu.cs.vbc.prog.checkstyle.api.TokenTypes;
import edu.cmu.cs.vbc.prog.checkstyle.api.Utils;
import edu.cmu.cs.vbc.prog.checkstyle.checks.AbstractOptionCheck;

/**
 * <p>Checks the padding of an empty for initializer; that is whether a
 * space is required at an empty for initializer, or such spaces are
 * forbidden. No check occurs if there is a line wrap at the initializer, as in
 * </p>
 * <pre class="body">
for (
      ; i &lt; j; i++, j--)
   </pre>
 * <p>
 * The policy to verify is specified using the {@link PadOption} class and
 * defaults to {@link PadOption#NOSPACE}.
 * </p>
 * <p>
 * An example of how to configure the check is:
 * </p>
 * <pre>
 * &lt;module name="EmptyForInitializerPad"/&gt;
 * </pre>
 *
 * @author lkuehne
 * @version 1.0
 */
public class EmptyForInitializerPadCheck
    extends AbstractOptionCheck<PadOption>
{

    /**
     * A key is pointing to the warning message text in "messages.properties"
     * file.
     */
    public static final String MSG_PRECEDED = "ws.preceded";

    /**
     * A key is pointing to the warning message text in "messages.properties"
     * file.
     */
    public static final String MSG_NOT_PRECEDED = "ws.notPreceded";

    /**
     * Sets the paren pad otion to nospace.
     */
    public EmptyForInitializerPadCheck()
    {
        super(PadOption.NOSPACE, PadOption.class);
    }

    @Override
    public int[] getDefaultTokens()
    {
        return new int[] {TokenTypes.FOR_INIT,
        };
    }

    @Override
    public int[] getAcceptableTokens()
    {
        return new int[] {TokenTypes.FOR_INIT,
        };
    }

    @Override
    public void visitToken(DetailAST ast)
    {
        if (ast.getChildCount() == 0) {
            //empty for initializer. test pad before semi.
            final DetailAST semi = ast.getNextSibling();
            final int semiLineIdx = semi.getLineNo() - 1;
            final String line = getLines()[semiLineIdx];
            final int before = semi.getColumnNo() - 1;
            //don't check if semi at beginning of line
            if (!Utils.whitespaceBefore(before, line)) {
                final PadOption option = getAbstractOption();
                if ((PadOption.NOSPACE == option)
                    && (Character.isWhitespace(line.charAt(before))))
                {
                    log(semi.getLineNo(), before, MSG_PRECEDED, ";");
                }
                else if ((PadOption.SPACE == option)
                         && !Character.isWhitespace(line.charAt(before)))
                {
                    log(semi.getLineNo(), before, MSG_NOT_PRECEDED, ";");
                }
            }
        }
    }
}
