/**
 * The contents of this file are subject to the OpenMRS Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://license.openmrs.org
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
 * License for the specific language governing rights and limitations
 * under the License.
 *
 * Copyright (C) OpenMRS, LLC.  All Rights Reserved.
 */
package org.eclipse.datatools.connectivity.oda.openmrs.ui.impl;

import java.util.Properties;

import org.eclipse.datatools.connectivity.oda.design.DataSetDesign;

/**
 * This class is to hold the public properties for the different data set pages.
 * The basic idea was taken from the publicly available XML ODA. This data
 * structure allows properties to be shared between the different data set pages
 * within the same user session.
 */
public class InformationHolder {

    private static final String QUERY = "QUERY";

    private static final String DATASTYLE = "DATASTYLE";

    private static final String FILTER = "FILTER";

    private static final String TOKENS = "TOKENS";

    private static final String TOKENTAG = "TOKENTAG";

    private static Properties prop;

    /**
     * Gets all of the properties.
     * 
     * @return the properties
     */
    public static Properties getProperties() {
        return prop;
    }

    /**
     * Gets the property value.
     * 
     * @param key the key
     * 
     * @return the property value
     */
    public static String getPropertyValue(String key) {

        if (prop == null)
            return null;

        String val = prop.getProperty(key);

        return val;
    }

    /**
     * Sets the property value.
     * 
     * @param key the key
     * @param value the value
     */
    public static void setPropertyValue(String key, String value) {
        if (prop == null) {
            prop = new Properties();
            ;
        }

        if (value != null) {
            prop.setProperty(key, value);
        }
    }

    /**
     * Initializes the InformationHolder. A DataSetDesign so that any existing
     * public properties can be extracted from the design.
     * 
     * @param dataSetDesign the data set design
     */
    public static void start(DataSetDesign dataSetDesign) {
        if (dataSetDesign == null) {
            return;
        }

        String queryText = dataSetDesign.getQueryText();

        if (queryText != null && queryText.trim().length() > 0) {
            setPropertyValue(QUERY, queryText);
        }

        if (dataSetDesign.getPublicProperties() != null) {

            String selectedTag = dataSetDesign.getPublicProperties()
                    .getProperty(TOKENTAG);

            String tokens = dataSetDesign.getPublicProperties().getProperty(
                    TOKENS);

            String filter = dataSetDesign.getPublicProperties().getProperty(
                    FILTER);

            String dataStyle = dataSetDesign.getPublicProperties().getProperty(
                    DATASTYLE);

            setPropertyValue(TOKENTAG, selectedTag);

            setPropertyValue(TOKENS, tokens);

            setPropertyValue(FILTER, filter);

            setPropertyValue(DATASTYLE, dataStyle);
        }
    }

    /**
     * destroy the holder class.
     */
    public static void destroy() {
        prop = null;
    }

    /**
     * Checks if destroyed to know whether or not start(DataSetDesign) needs to
     * be called.
     * 
     * @return true, if destroyed
     */
    public static boolean hasDestroyed() {
        return prop == null;
    }
}