/**
 * Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership. Apereo
 * 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 the
 * following location:
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0
 *
 * <p>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.
 */
package org.apereo.portal.layout.dlm;

import org.apache.commons.lang.Validate;

/**
 * Uniquely identifies a node within some DLM layout for use in external data XML. A Pethref is the
 * opposite (counterpart) of a {@link Noderef}. In other words, a {@link Noderef} identifies
 * internally what a Pathref identifies externally. The need for two formats stems from the fact
 * that {@link Noderef}s use database identifiers in their format, which are not (always) stable
 * across migrations.<br>
 * Pathrefs contain either 2 or 3 elements:
 *
 * <ul>
 *   <li>username of the fragment owner (e.g. 'admin-lo')
 *   <li>XPath that uniquely identifies a layout node (e.g. '/layout/folder/folder[3]')
 *   <li><strong>SOMETIMES</strong> a portlet fname (layout nodes referring to portlets only)
 * </ul>
 *
 */
public final class Pathref {

    private static final String TOKEN_DELIMITER = ":";

    // Instance Members
    private final String layoutOwnerUsername;
    private final String uniquePath;
    private final String portletFname;

    public Pathref(String layoutOwnerUsername, String uniquePath, String portletFname) {

        Validate.notNull(layoutOwnerUsername, "Argument 'layoutOwnerUsername' cannot be null.");
        Validate.notNull(uniquePath, "Argument 'uniquePath' cannot be null.");
        // NB:  portletFname can and SHOULD be null for Pathrefs that refer to non-portlet nodes

        this.layoutOwnerUsername = layoutOwnerUsername;
        this.uniquePath = uniquePath;
        this.portletFname = portletFname;
    }

    public String getLayoutOwnerUsername() {
        return layoutOwnerUsername;
    }

    public String getUniquePath() {
        return uniquePath;
    }

    public String getPortletFname() {
        return portletFname;
    }

    @Override
    public String toString() {
        return layoutOwnerUsername + TOKEN_DELIMITER + uniquePath;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result =
                prime * result
                        + ((layoutOwnerUsername == null) ? 0 : layoutOwnerUsername.hashCode());
        result = prime * result + ((portletFname == null) ? 0 : portletFname.hashCode());
        result = prime * result + ((uniquePath == null) ? 0 : uniquePath.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) return true;
        if (obj == null) return false;
        if (getClass() != obj.getClass()) return false;
        Pathref other = (Pathref) obj;
        if (layoutOwnerUsername == null) {
            if (other.layoutOwnerUsername != null) return false;
        } else if (!layoutOwnerUsername.equals(other.layoutOwnerUsername)) return false;
        if (portletFname == null) {
            if (other.portletFname != null) return false;
        } else if (!portletFname.equals(other.portletFname)) return false;
        if (uniquePath == null) {
            if (other.uniquePath != null) return false;
        } else if (!uniquePath.equals(other.uniquePath)) return false;
        return true;
    }
}