/*******************************************************************************
 * Copyright (c) 2013 GigaSpaces Technologies Ltd. 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.
 ******************************************************************************/
package org.cloudifysource.esc.driver.provisioning.privateEc2.parser.deserializers;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Logger;

import org.cloudifysource.esc.driver.provisioning.privateEc2.parser.beans.AWSEC2Instance;
import org.cloudifysource.esc.driver.provisioning.privateEc2.parser.beans.AWSEC2Volume;
import org.cloudifysource.esc.driver.provisioning.privateEc2.parser.beans.AWSResource;
import org.codehaus.jackson.JsonNode;
import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.JsonToken;
import org.codehaus.jackson.ObjectCodec;
import org.codehaus.jackson.map.DeserializationContext;
import org.codehaus.jackson.map.JsonDeserializer;

/**
 * A deserializer for Amazon CloudFormation resources.<br />
 * This class will create a specific bean for <code>AWS::EC2::Instance</code> and <code>AWS::EC2::Volume</code>.
 * 
 * @author victor
 * @since 2.7.0
 * 
 */
public class ResourcesDeserializer extends JsonDeserializer<List<AWSResource>> {

	protected final Logger logger = Logger.getLogger(this.getClass().getName());

	public ResourcesDeserializer() {
	}

	@Override
	public List<AWSResource> deserialize(final JsonParser jp, final DeserializationContext ctxt) throws IOException {
		List<AWSResource> resources = new ArrayList<AWSResource>();
		if (JsonToken.START_OBJECT != jp.getCurrentToken()) {
			throw ctxt.mappingException("Expected START OBJECT got: " + jp.getCurrentName());
		}

		// next Resources
		while (JsonToken.END_OBJECT != jp.nextToken()) {
			AWSResource deserialize = deserializeResource(jp, ctxt);
			if (deserialize != null) {
				resources.add(deserialize);
			}
		}

		return resources;
	}

	private AWSResource deserializeResource(final JsonParser jp, final DeserializationContext ctxt) throws IOException {
		String resourceName = jp.getText();

		jp.nextToken();
		JsonNode jsonNode = jp.readValueAsTree();
		String type = jsonNode.path("Type").getTextValue();
		ObjectCodec codec = jp.getCodec();
		if (type != null && type.startsWith("AWS::")) {
			if ("AWS::EC2::Instance".equals(type)) {
				AWSEC2Instance instance = codec.treeToValue(jsonNode, AWSEC2Instance.class);
				instance.setResourceName(resourceName);
				return instance;
			} else if ("AWS::EC2::Volume".equals(type)) {
				AWSEC2Volume instance = codec.treeToValue(jsonNode, AWSEC2Volume.class);
				instance.setResourceName(resourceName);
				return instance;
			} else {
				logger.warning("The parsing do not handle resource type " + type);
				return null;
			}
		}
		throw ctxt.mappingException("Node is of type AWS::EC2 resources: " + resourceName);
	}
}