/*******************************************************************************
 * ============LICENSE_START====================================================
 * * org.onap.aaf
 * * ===========================================================================
 * * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
 * * ===========================================================================
 * * Licensed 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
 * * 
 *  *      http://www.apache.org/licenses/LICENSE-2.0
 * * 
 *  * 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.
 * * ============LICENSE_END====================================================
 * *
 * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 * *
 ******************************************************************************/
/**
 * JAXBumar.java
 *
 * Created on: Apr 10, 2009
 * Created by: 
 *
 * Revamped to do away with ThreadLocal 5/27/2011,
 *
 * (c) 2009 SBC Knowledge Ventures, L.P. All rights reserved.
 ******************************************************************* 
 * RESTRICTED - PROPRIETARY INFORMATION The Information contained 
 * herein is for use only by authorized employees of AT&T Services, 
 * Inc., and authorized Affiliates of AT&T Services, Inc., and is 
 * not for general distribution within or outside the respective 
 * companies. 
 *******************************************************************
 */
package org.onap.aaf.inno.env.jaxb;

import java.io.OutputStream;
import java.io.StringWriter;
import java.io.Writer;
import java.util.HashMap;
import java.util.Map;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.namespace.QName;

import org.onap.aaf.inno.env.APIException;
import org.onap.aaf.inno.env.LogTarget;
import org.onap.aaf.inno.env.util.Pool;
import org.onap.aaf.inno.env.util.Pool.Pooled;

/**
 * JAXBmar classes are inexpensive for going in and out of scope
 * and have been made thread safe via Pooling

 *
 */
public class JAXBmar {
	// Need to store off possible JAXBContexts based on Class, which will be stored in Creator
	private static Map<Class<?>[],Pool<PMarshaller>> pools = new HashMap<Class<?>[], Pool<PMarshaller>>();

	// Handle Marshaller class setting of properties only when needed
	private class PMarshaller {
		private Marshaller m;
		private boolean p;
		private boolean f;
		
		public PMarshaller(Marshaller marshaller) throws JAXBException {
			m = marshaller;
    		m.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
    		m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, p = false);
    		m.setProperty(Marshaller.JAXB_FRAGMENT, f = false);
		}
		
		public Marshaller get(boolean pretty, boolean fragment) throws JAXBException {
			if(pretty != p) {
	    		m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, p = pretty);
			}
			if(fragment != f) {
	    		m.setProperty(Marshaller.JAXB_FRAGMENT, f = fragment);
			}
			return m;
		}
	}
	
	private class Creator implements Pool.Creator<PMarshaller> {
		private JAXBContext jc;
		private String name;
		public Creator(Class<?>[] classes) throws JAXBException {
			jc = JAXBContext.newInstance(classes);
			name = "JAXBmar: " + classes[0].getName();
		}
		
		// @Override
		public PMarshaller create() throws APIException {
			try {
				return new PMarshaller(jc.createMarshaller());
			} catch (JAXBException e) {
				throw new APIException(e);
			}
		}

		public String toString() {
			return name;
		}

		// @Override
		public void reuse(PMarshaller pm) {
			// Nothing to do
		}
		
		// @Override
		public void destroy(PMarshaller pm) {
			// Nothing to do
		}

		// @Override
		public boolean isValid(PMarshaller t) {
			return true; 
		}
	}

	//TODO isn't UTF-8 a standard string somewhere for encoding?
	private boolean fragment= false;
	private boolean pretty=false;
	private QName qname;
	
	private Pool<PMarshaller> mpool; // specific Pool associated with constructed Classes
	private Class<?> cls;
	
	private Pool<PMarshaller> getPool(Class<?> ... classes) throws JAXBException {
		Pool<PMarshaller> mp;
		synchronized(pools) {
			mp = pools.get(classes);
			if(mp==null) {
				pools.put(classes,mp = new Pool<PMarshaller>(new Creator(classes)));
			}
		}		
		return mp;
	}
	
	public JAXBmar(Class<?>... classes) throws JAXBException {
		cls = classes[0];
		mpool = getPool(classes);
		qname = null;
	}

	public JAXBmar(QName theQname, Class<?>... classes) throws JAXBException {
		cls = classes[0];
		mpool = getPool(classes);
		qname = theQname;
	}

	@SuppressWarnings("unchecked")
	public<O> O marshal(LogTarget lt,O o, Writer writer, boolean ... options) throws JAXBException, APIException {
		boolean pretty, fragment;
		pretty = options.length>0?options[0]:this.pretty;
		fragment = options.length>1?options[1]:this.fragment;
		Pooled<PMarshaller> m = mpool.get(lt);
		try {
			if(qname==null) {
				m.content.get(pretty,fragment).marshal(o, writer);
			} else {
				m.content.get(pretty,fragment).marshal(
					new JAXBElement<O>(qname, (Class<O>)cls, o ),
					writer);
			}
			return o;
		} finally {
			m.done();
		}
	}

	@SuppressWarnings("unchecked")
	public<O> O marshal(LogTarget lt, O o, OutputStream os, boolean ... options) throws JAXBException, APIException {
		boolean pretty, fragment;
		pretty = options.length>0?options[0]:this.pretty;
		fragment = options.length>1?options[1]:this.fragment;
		Pooled<PMarshaller> m = mpool.get(lt);
		try {
			if(qname==null) {
				m.content.get(pretty,fragment).marshal(o, os);
			} else {
				m.content.get(pretty,fragment).marshal(
					new JAXBElement<O>(qname, (Class<O>)cls, o ),os);
			}
			return o;
		} finally {
			m.done();
		}
	}
	
	public<O> O marshal(LogTarget lt, O o, Writer writer, Class<O> clss) throws JAXBException, APIException {
		Pooled<PMarshaller> m = mpool.get(lt);
		try {
			if(qname==null) {
				m.content.get(pretty,fragment).marshal(o, writer);
			} else {
				m.content.get(pretty,fragment).marshal(
					new JAXBElement<O>(qname, clss, o),writer);
			}
			return o;
		} finally {
			m.done();
		}
			
	}

	public<O> O marshal(LogTarget lt, O o, OutputStream os, Class<O> clss) throws JAXBException, APIException {
		Pooled<PMarshaller> m = mpool.get(lt);
		try {
			if(qname==null) { 
				m.content.get(pretty,fragment).marshal(o, os);
			} else {
				m.content.get(pretty,fragment).marshal(
					new JAXBElement<O>(qname, clss, o ),os);
			}
			return o;
		} finally {
			m.done();
		}
	}

	/**
	 * @return
	 */
	public Class<?> getMarshalClass() {
		return cls;
	}

	public<O> String stringify(LogTarget lt, O o) throws JAXBException, APIException {
		StringWriter sw = new StringWriter();
		marshal(lt,o,sw);
		return sw.toString();
	}

	public JAXBmar pretty(boolean pretty) {
		this.pretty = pretty;
		return this;
	}
	
	public JAXBmar asFragment(boolean fragment) {
		this.fragment = fragment;
		return this;
	}
}