ProjectModelStatus.java

package org.sigmah.shared.dto.referential;

/*
 * #%L
 * Sigmah
 * %%
 * Copyright (C) 2010 - 2016 URD
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-3.0.html>.
 * #L%
 */


import org.sigmah.client.i18n.I18N;
import org.sigmah.shared.command.result.Result;
import org.sigmah.shared.util.Pair;

import com.google.gwt.core.client.GWT;

/**
 * The different status of projects.
 * 
 * @author nrebiai (v1.3)
 * @author Denis Colliot (dcolliot@ideia.fr) (v2.0)
 * @author Renato Almeida (renatoaf.ufcg@gmail.com)
 */
public enum ProjectModelStatus implements Result {

	DRAFT(true),
	READY,
	USED,
	UNAVAILABLE,
	UNDER_MAINTENANCE(true);
	
	/**
	 * Gets the translation value for the given {@code status}. To use only on the client-side.
	 * 
	 * @param status
	 *          The {@code ProjectModelStatus} value.
	 * @return The translation value for the given {@code status}.
	 */
	public static String getName(final ProjectModelStatus status) {

		if (status == null) {
			return null;
		}

		if (!GWT.isClient()) {
			return status.name();
		}

		switch (status) {
			case DRAFT:
				return I18N.CONSTANTS.DRAFT();
			case READY:
				return I18N.CONSTANTS.READY();
			case USED:
				return I18N.CONSTANTS.USED();
			case UNAVAILABLE:
				return I18N.CONSTANTS.UNAVAILABLE();
			case UNDER_MAINTENANCE:
				return I18N.CONSTANTS.UNDER_MAINTENANCE();
			default:
				return status.name();
		}
	}

	/**
	 * Returns the given {@code status} corresponding {@code ProjectModelStatus} instance.
	 * Default returned value is {@link #DRAFT}.
	 * 
	 * @param status
	 *          The project model status text.
	 * @return the given {@code status} corresponding {@code ProjectModelStatus} instance.
	 */
	public static ProjectModelStatus getStatus(final String status) {

		final ProjectModelStatus statusEnum;

		if (I18N.CONSTANTS.DRAFT().equals(status)) {
			statusEnum = DRAFT;

		} else if (I18N.CONSTANTS.READY().equals(status)) {
			statusEnum = READY;

		} else if (I18N.CONSTANTS.USED().equals(status)) {
			statusEnum = USED;

		} else if (I18N.CONSTANTS.UNAVAILABLE().equals(status)) {
			statusEnum = UNAVAILABLE;
			
		} else if(I18N.CONSTANTS.UNDER_MAINTENANCE().equals(status)) {
			statusEnum = UNDER_MAINTENANCE;

		} else {
			statusEnum = DRAFT;
		}

		return statusEnum;
	}
	
	/**
	 * Check if a model's status change is valid.
	 * 
	 * @param currentStatus
	 *          The current status of the model.
	 * @param targetStatus
	 *          The new selected status that should be controlled.
	 * @return A pair containing the change valid flag with its error message (if not valid).
	 */
	public static Pair<Boolean, String> isValidStatusChange(final ProjectModelStatus currentStatus, final ProjectModelStatus targetStatus) {

		if (currentStatus == ProjectModelStatus.DRAFT && targetStatus != ProjectModelStatus.READY) {
			// "DRAFT" status is only allowed to shift to "READY" status.
			return new Pair<Boolean, String>(false, I18N.CONSTANTS.draftModelStatusChangeError());

		} else if (currentStatus == ProjectModelStatus.READY && targetStatus != ProjectModelStatus.DRAFT && targetStatus != ProjectModelStatus.UNAVAILABLE) {
			// "READY" status is only allowed to shift to "DRAFT" or "UNAVAILABLE" status.
			return new Pair<Boolean, String>(false, I18N.CONSTANTS.readyModelStatusChangeError());

		} else if (currentStatus.equals(ProjectModelStatus.USED) && !targetStatus.equals(ProjectModelStatus.UNAVAILABLE)) {
			// "USED" status is only allowed to shift to "UNAVAILABLE" status.
			return new Pair<Boolean, String>(false, I18N.CONSTANTS.usedModelStatusChangeError());

		} else {
			// Others cases are all allowed.
			return new Pair<Boolean, String>(true, null);
		}
	}

	private final boolean editable;
	
	private ProjectModelStatus() {
		this(false);
	}
	
	private ProjectModelStatus(boolean editable) {
		this.editable = editable;
	}

	/**
	 * Returns <code>true</code> if the state allows modifications to be done
	 * on a model.
	 * 
	 * @return <code>true</code> if the state allows modifications, 
	 * <code>false</code> otherwise.
	 */
	public boolean isEditable() {
		return editable;
	}
	
}