package org.apache.maven.scm;

import java.io.Serializable;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

/**
 * @TODO move to a real enum
 * <p/>
 * Typesafe enum for file status
 * </p>
 * <p/>
 * There are two types of status defined in this class: <br/>
 * 1) Status: Changes in the working tree, not yet committed to the repository eg. MODIFIED <br/>
 * 2) Transaction: The file is part of some transaction with the repository eg. CHECKED_IN
 * </p>
 *
 * @author <a href="mailto:trygvis@inamo.no">Trygve Laugst&oslash;l</a>
 * @version $Id$
 */
public final class ScmFileStatus
    implements Serializable
{
    private static final long serialVersionUID = -7840223279162817915L;

    /**
     * File is added to the working tree and does not yet exist in the repository
     */
    public static final ScmFileStatus ADDED = new ScmFileStatus( "added" );

    /**
     * File is removed from the working tree thus not revisioned anymore.<br>
     * The file is still present in the repository.<br>
     * The file could be deleted from the filesystem depending on the provider.
     */
    public static final ScmFileStatus DELETED = new ScmFileStatus( "deleted" );

    /**
     * The file has been modified in the working tree.
     */
    public static final ScmFileStatus MODIFIED = new ScmFileStatus( "modified" );

    /**
     * The file is missing in the working tree.
     */
    public static final ScmFileStatus MISSING = new ScmFileStatus( "missing" );

    /**
     * File from working tree is checked into the repository
     */
    public static final ScmFileStatus CHECKED_IN = new ScmFileStatus( "checked-in" );

    /**
     * File is checked out from the repository and into the working tree
     */
    public static final ScmFileStatus CHECKED_OUT = new ScmFileStatus( "checked-out" );

    /**
     * The file in the working tree has differences to the one in repository that
     * conflicts ie. it cannot automatically be merged.
     */
    public static final ScmFileStatus CONFLICT = new ScmFileStatus( "conflict" );

    /**
     * The file in the working tree has been updated with changes from the repository.
     */
    public static final ScmFileStatus PATCHED = new ScmFileStatus( "patched" );

    /**
     * The file is added, removed or updated from the repository, thus its
     * up-to-date with the version in the repository. See also isUpdate()
     */
    public static final ScmFileStatus UPDATED = new ScmFileStatus( "updated" );

    /**
     * The file is part of a tag.
     */
    public static final ScmFileStatus TAGGED = new ScmFileStatus( "tagged" );

    /**
     * The file is locked.
     */
    public static final ScmFileStatus LOCKED = new ScmFileStatus( "locked" );

    /**
     * The file is in the working tree but is not versioned and not ignored either.
     */
    public static final ScmFileStatus UNKNOWN = new ScmFileStatus( "unknown" );

    /**
     * @since 1.5
     * The file is being edited
     */
    public static final ScmFileStatus EDITED = new ScmFileStatus( "edit" );
    
    /**
     * The status name
     */
    private final String name;

    private ScmFileStatus( String name )
    {
        this.name = name;
    }

    /** {@inheritDoc} */
    public String toString()
    {
        return name;
    }

    /**
     * There are changes in the working tree that are not committed to the repository, or <br>
     * the file is unknown for the working tree.
     *
     * @return true on changes in the working tree or if the file is unknown.
     */
    public boolean isStatus()
    {
        return this == UNKNOWN || isDiff();
    }

    /**
     * There are changes in the working tree that are not committed to the repository. <br>
     *
     * @return true on changes in the working tree
     */
    public boolean isDiff()
    {
        return this == ADDED || this == DELETED || this == MODIFIED;
    }

    /**
     * @return true if the file was part of a transaction with the repository.
     */
    public boolean isTransaction()
    {
        return this == CHECKED_IN || this == CHECKED_OUT || this == LOCKED || this == TAGGED || isUpdate();
    }

    /**
     * File is part of an update transaction with the repository.<br>
     * Note: ADDED and REMOVED are not an update status since they indicates
     * that the working tree has changed.<br>
     * An update indicates the opposite, that the repository was changed compared to
     * the working tree and that it is now synchronized unless there are conflicts.
     *
     * @return true if the status is conflict, updated or patched.
     */
    public boolean isUpdate()
    {
        return this == CONFLICT || this == UPDATED || this == PATCHED;
    }
}