source: trunk/src/org/expeditee/setting/GenericSetting.java@ 1209

/**
 *    GenericSetting.java
 *    Copyright (C) 2010 New Zealand Digital Library, http://expeditee.org
 *
 *    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/>.
 */

package org.expeditee.setting;

import org.expeditee.gui.AttributeValuePair;
import org.expeditee.items.Text;

/**
 * Generic setting class for storing simple settings
 * 
 * @author jts21
 *
 * @param <T> type of the setting
 */
public abstract class GenericSetting<T> extends VariableSetting {

        protected final Class<T> _type;
        protected T _default;
        protected T _value;
        
        /**
         * Instantiates a new setting
         * @param type Reference to the type of the setting, since Java's generics implementation apparently got
         *      dropped on it's head at some point, and we can't know what type the generic object is at runtime without
         *      manually passing a reference to the class
         * @param tooltip Tooltip text to display (once tooltips are implemented)
         * @param value Default value
         */
        public GenericSetting(Class<T> type, String tooltip, T value) {
                super(tooltip);
                _type = type;
                _default = value;
                _value = value;
        }
        
        /**
         * Instantiates a new setting with no default value
         */
        public GenericSetting(Class<T> type, String tooltip) {
                this(type, tooltip, (T) saneInitialValue(type));
        }
        
        /**
         * @return true if this setting is a String, Number or Boolean
         */
        public boolean isPrimitive() {
                return _type.equals(String.class) || _type.equals(Integer.class) || _type.equals(Float.class) || _type.equals(Double.class) || _type.equals(Boolean.class);
        }
        
        /**
         * Provides a sane initial value for settings with no default value
         */
        private static Object saneInitialValue(Class<?> type) {
                if(type.equals(String.class)) {
                        return "";
                } else if(type.equals(Integer.class) || type.equals(Float.class) || type.equals(Double.class)) {
                        return 0;
                } else if(type.equals(Boolean.class)) {
                        return false;
                }
                return null;
        }
        
        /**
         * @return the type of this setting
         */
        public Class<T> getType() {
                return _type;
        }
        
        /**
         * @return the value of this setting
         */
        public T get() {
                return _value;
        }
        
        /**
         * Sets the value directly
         */
        public void set(T value) {
                _value = value;
        }
        
        public boolean setSetting(Text text) {
                AttributeValuePair avp = new AttributeValuePair(text.getText(), false);
                if(avp.hasAttribute() && avp.getValue().trim().length() != 0) {
                if(_type.equals(String.class)) {
                        String value = avp.getValue();
                        if(value.trim().length() == 0) {
                                return false;
                        }
                        set((T) value);
                } else if(_type.equals(Integer.class)) {
                        set((T) avp.getIntegerValue());
                } else if(_type.equals(Float.class)) {
                        set((T) (Float) avp.getDoubleValue().floatValue());
                } else if(_type.equals(Double.class)) {
                        set((T) avp.getDoubleValue());
                } else if(_type.equals(Boolean.class)) {
                        set((T) (Boolean) avp.getBooleanValue());
                } else if(_type.equals(Text.class)) {
                        set((T) text);
                } else {
                        System.err.println("Invalid type: " + _type.getName());
                        return false;
                }
                return true;
                }
                return false;
        }
        
        public void setDefault(T value) {
                _default = value;
        }
        
        /**
         * Reset the value back to the default, if a default value was specified
         */
        public void reset() {
                _value = _default;
        }

}