// ========================================================================
// Copyright (c) 2004-2009 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
// The Eclipse Public License is available at 
// http://www.eclipse.org/legal/epl-v10.html
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
// You may elect to redistribute this code under either of these licenses. 
// ========================================================================
package net.hasor.utils.json;
import net.hasor.utils.json.JSON.Output;

import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
/* ------------------------------------------------------------ */

/**
 * Convert an Object to JSON using reflection on getters methods.
 *
 *
 *
 */
public class JSONObjectConvertor implements JSON.Convertor {
    private boolean _fromJSON;
    private Set     _excluded = null;

    public JSONObjectConvertor() {
        _fromJSON = false;
    }

    public JSONObjectConvertor(boolean fromJSON) {
        _fromJSON = fromJSON;
    }
    /* ------------------------------------------------------------ */

    /**
     * @param fromJSON
     * @param excluded An array of field names to exclude from the conversion
     */
    public JSONObjectConvertor(boolean fromJSON, String[] excluded) {
        _fromJSON = fromJSON;
        if (excluded != null)
            _excluded = new HashSet(Arrays.asList(excluded));
    }

    public Object fromJSON(Map map) {
        if (_fromJSON)
            throw new UnsupportedOperationException();
        return map;
    }

    public void toJSON(Object obj, Output out) {
        try {
            Class c = obj.getClass();
            if (_fromJSON)
                out.addClass(obj.getClass());
            Method[] methods = obj.getClass().getMethods();
            for (int i = 0; i < methods.length; i++) {
                Method m = methods[i];
                if (!Modifier.isStatic(m.getModifiers()) && m.getParameterTypes().length == 0 && m.getReturnType() != null && m.getDeclaringClass() != Object.class) {
                    String name = m.getName();
                    if (name.startsWith("is"))
                        name = name.substring(2, 3).toLowerCase() + name.substring(3);
                    else if (name.startsWith("get"))
                        name = name.substring(3, 4).toLowerCase() + name.substring(4);
                    else
                        continue;
                    if (includeField(name, obj, m))
                        out.add(name, m.invoke(obj, (Object[]) null));
                }
            }
        } catch (Throwable e) {
            throw new IllegalArgumentException(e);
        }
    }

    protected boolean includeField(String name, Object o, Method m) {
        return _excluded == null || !_excluded.contains(name);
    }
}
