/*
 * Copyright 2013-2016 the original author or authors.
 *
 * 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.springframework.integration.support.json;

import java.io.File;
import java.io.InputStream;
import java.io.Reader;
import java.io.Writer;
import java.lang.reflect.Type;
import java.net.URL;
import java.util.Collection;
import java.util.Map;

import org.springframework.integration.mapping.support.JsonHeaders;
import org.springframework.util.Assert;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.MapperFeature;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * Jackson 2 JSON-processor (@link https://github.com/FasterXML) {@linkplain JsonObjectMapper} implementation.
 * Delegates <code>toJson</code> and <code>fromJson</code>
 * to the {@linkplain com.fasterxml.jackson.databind.ObjectMapper}
 * <p>
 * It customizes Jackson's default properties with the following ones:
 * <ul>
 * <li>{@link MapperFeature#DEFAULT_VIEW_INCLUSION} is disabled</li>
 * <li>{@link DeserializationFeature#FAIL_ON_UNKNOWN_PROPERTIES} is disabled</li>
 * </ul>
 *
 * @author Artem Bilan
 * @since 3.0
 */
public class Jackson2JsonObjectMapper extends AbstractJacksonJsonObjectMapper<JsonNode, JsonParser, JavaType> {

	private final ObjectMapper objectMapper;

	public Jackson2JsonObjectMapper() {
		this.objectMapper = new ObjectMapper();
		this.objectMapper.configure(MapperFeature.DEFAULT_VIEW_INCLUSION, false);
		this.objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
	}

	public Jackson2JsonObjectMapper(ObjectMapper objectMapper) {
		Assert.notNull(objectMapper, "objectMapper must not be null");
		this.objectMapper = objectMapper;
	}

	@Override
	public String toJson(Object value) throws Exception {
		return this.objectMapper.writeValueAsString(value);
	}

	@Override
	public void toJson(Object value, Writer writer) throws Exception {
		this.objectMapper.writeValue(writer, value);
	}

	@Override
	public JsonNode toJsonNode(Object value) throws Exception {
		return this.objectMapper.valueToTree(value);
	}

	@Override
	protected <T> T fromJson(Object json, JavaType type) throws Exception {
		if (json instanceof String) {
			return this.objectMapper.readValue((String) json, type);
		}
		else if (json instanceof byte[]) {
			return this.objectMapper.readValue((byte[]) json, type);
		}
		else if (json instanceof File) {
			return this.objectMapper.readValue((File) json, type);
		}
		else if (json instanceof URL) {
			return this.objectMapper.readValue((URL) json, type);
		}
		else if (json instanceof InputStream) {
			return this.objectMapper.readValue((InputStream) json, type);
		}
		else if (json instanceof Reader) {
			return this.objectMapper.readValue((Reader) json, type);
		}
		else {
			throw new IllegalArgumentException("'json' argument must be an instance of: " + supportedJsonTypes
					+ " , but gotten: " + json.getClass());
		}
	}

	@Override
	public <T> T fromJson(JsonParser parser, Type valueType) throws Exception {
		return this.objectMapper.readValue(parser, constructType(valueType));
	}

	@Override
	@SuppressWarnings({ "unchecked" })
	protected JavaType extractJavaType(Map<String, Object> javaTypes) throws Exception {
		JavaType classType = this.createJavaType(javaTypes, JsonHeaders.TYPE_ID);
		if (!classType.isContainerType() || classType.isArrayType()) {
			return classType;
		}

		JavaType contentClassType = this.createJavaType(javaTypes, JsonHeaders.CONTENT_TYPE_ID);
		if (classType.getKeyType() == null) {
			return this.objectMapper.getTypeFactory()
					.constructCollectionType((Class<? extends Collection<?>>) classType.getRawClass(), contentClassType);
		}

		JavaType keyClassType = this.createJavaType(javaTypes, JsonHeaders.KEY_TYPE_ID);
		return this.objectMapper.getTypeFactory()
				.constructMapType((Class<? extends Map<?, ?>>) classType.getRawClass(), keyClassType, contentClassType);
	}

	@Override
	protected JavaType constructType(Type type) {
		return this.objectMapper.constructType(type);
	}

}