////////////////////////////////////////////////////////////////////////////////

// checkstyle: Checks Java source code for adherence to a set of rules.

// Copyright (C) 2001-2012  Oliver Burn

//

// 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 com.puppycrawl.tools.checkstyle.checks.naming;



import com.puppycrawl.tools.checkstyle.api.DetailAST;

import com.puppycrawl.tools.checkstyle.api.TokenTypes;

import com.puppycrawl.tools.checkstyle.checks.AbstractFormatCheck;



/**

 * <p>

 * Ensures that the names of abstract classes conforming to some

 * regular expression and check that <code>abstract</code> modifier exists.

 * </p>

 * <p>

 * Rationale: Abstract classes are convenience base class

 * implementations of interfaces, not types as such. As such

 * they should be named to indicate this. Also if names of classes

 * starts with 'Abstract' it's very convenient that they will

 * have abstract modifier.

 * </p>

 *

 * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a>

 * @author <a href="mailto:solid.danil@gmail.com">Danil Lopatin</a>

 */

public final class AbstractClassNameCheck extends AbstractFormatCheck

{

    /** Default format for abstract class names */

    private static final String DEFAULT_FORMAT = "^Abstract.*$|^.*Factory$";



    /** whether to ignore checking the modifier */

    private boolean mIgnoreModifier;



    /** whether to ignore checking the name */

    private boolean mIgnoreName;



    /** Creates new instance of the check. */

    public AbstractClassNameCheck()

    {

        super(DEFAULT_FORMAT);

    }



    /**

     * Whether to ignore checking for the <code>abstract</code> modifier.

     * @param aValue new value

     */

    public void setIgnoreModifier(boolean aValue)

    {

        mIgnoreModifier = aValue;

    }



    /**

     * Whether to ignore checking the name.

     * @param aValue new value.

     */

    public void setIgnoreName(boolean aValue)

    {

        mIgnoreName = aValue;

    }



    @Override

    public int[] getDefaultTokens()

    {

        return new int[]{TokenTypes.CLASS_DEF};

    }



    @Override

    public int[] getRequiredTokens()

    {

        return getDefaultTokens();

    }



    @Override

    public void visitToken(DetailAST aAST)

    {

        if (TokenTypes.CLASS_DEF == aAST.getType()) {

            visitClassDef(aAST);

        }

    }



    /**

     * Checks class definition.

     * @param aAST class definition for check.

     */

    private void visitClassDef(DetailAST aAST)

    {

        final String className =

            aAST.findFirstToken(TokenTypes.IDENT).getText();

        if (isAbstract(aAST)) {

            // if class has abstract modifier

            if (!mIgnoreName && !isMatchingClassName(className)) {

                log(aAST.getLineNo(), aAST.getColumnNo(),

                    "illegal.abstract.class.name", className, getFormat());

            }

        }

        else if (!mIgnoreModifier && isMatchingClassName(className)) {

            log(aAST.getLineNo(), aAST.getColumnNo(),

                "no.abstract.class.modifier", className);

        }

    }



    /**

     * @param aAST class definition for check.

     * @return true if a given class declared as abstract.

     */

    private boolean isAbstract(DetailAST aAST)

    {

        final DetailAST abstractAST = aAST.findFirstToken(TokenTypes.MODIFIERS)

            .findFirstToken(TokenTypes.ABSTRACT);



        return abstractAST != null;

    }



    /**

     * @param aClassName class name for check.

     * @return true if class name matches format of abstract class names.

     */

    private boolean isMatchingClassName(String aClassName)

    {

        return getRegexp().matcher(aClassName).find();

    }

}