////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2014  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.api;

import java.io.File;
import java.util.List;
import java.util.TreeSet;

import com.puppycrawl.tools.checkstyle.Utils;

/**
 * Provides common functionality for many FileSetChecks.
 *
 * @author lkuehne
 * @author oliver
 */
public abstract class AbstractFileSetCheck
    extends AbstractViolationReporter
    implements FileSetCheck
{
    /** The dispatcher errors are fired to. */
    private MessageDispatcher dispatcher;

    /** the file extensions that are accepted by this filter */
    private String[] fileExtensions = {};

    /** collects the error messages */
    private final LocalizedMessages messages = new LocalizedMessages();

    /**
     * Called to process a file that matches the specified file extensions.
     * @param file the file to be processed
     * @param lines an immutable list of the contents of the file.
     */
    protected abstract void processFiltered(File file, List<String> lines);

    /** {@inheritDoc} */
    @Override
    public void init()
    {
    }

    /** {@inheritDoc} */
    @Override
    public void destroy()
    {
    }

    /** {@inheritDoc} */
    @Override
    public void beginProcessing(String charset)
    {
    }

    /** {@inheritDoc} */
    @Override
    public final TreeSet<LocalizedMessage> process(File file,
                                                   List<String> lines)
    {
        getMessageCollector().reset();
        // Process only what interested in
        if (Utils.fileExtensionMatches(file, fileExtensions)) {
            processFiltered(file, lines);
        }
        return getMessageCollector().getMessages();
    }

    /** {@inheritDoc} */
    @Override
    public void finishProcessing()
    {
    }

    /** {@inheritDoc} */
    @Override
    public final void setMessageDispatcher(MessageDispatcher dispatcher)
    {
        this.dispatcher = dispatcher;
    }

    /**
     * A message dispatcher is used to fire violation messages to
     * interested audit listeners.
     *
     * @return the current MessageDispatcher.
     */
    protected final MessageDispatcher getMessageDispatcher()
    {
        return dispatcher;
    }

    /**
     * Sets the file extensions that identify the files that pass the
     * filter of this FileSetCheck.
     * @param extensions the set of file extensions. A missing
     * initial '.' character of an extension is automatically added.
     */
    public final void setFileExtensions(String[] extensions)
    {
        if (extensions == null) {
            fileExtensions = null;
            return;
        }

        fileExtensions = new String[extensions.length];
        for (int i = 0; i < extensions.length; i++) {
            final String extension = extensions[i];
            if (extension.startsWith(".")) {
                fileExtensions[i] = extension;
            }
            else {
                fileExtensions[i] = "." + extension;
            }
        }
    }

    /**
     * Returns the collector for violation messages.
     * Subclasses can use the collector to find out the violation
     * messages to fire via the message dispatcher.
     *
     * @return the collector for localized messages.
     */
    protected final LocalizedMessages getMessageCollector()
    {
        return messages;
    }

    @Override
    public final void log(int line, String key, Object... args)
    {
        log(line, 0, key, args);
    }

    @Override
    public final void log(int lineNo, int colNo, String key,
            Object... args)
    {
        getMessageCollector().add(
            new LocalizedMessage(lineNo,
                                 colNo,
                                 getMessageBundle(),
                                 key,
                                 args,
                                 getSeverityLevel(),
                                 getId(),
                                 this.getClass(),
                                 this.getCustomMessages().get(key)));
    }

    /**
     * Notify all listeners about the errors in a file.
     * Calls <code>MessageDispatcher.fireErrors()</code> with
     * all logged errors and than clears errors' list.
     * @param fileName the audited file
     */
    protected final void fireErrors(String fileName)
    {
        final TreeSet<LocalizedMessage> errors = getMessageCollector()
                .getMessages();
        getMessageCollector().reset();
        getMessageDispatcher().fireErrors(fileName, errors);
    }
}