package at.gv.egiz.eaaf.modules.auth.sl20.utils;

import java.io.IOException;
import java.io.InputStream;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.lang.NonNull;

import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.type.TypeFactory;

import at.gv.egiz.eaaf.core.api.utils.IJsonMapper;
import at.gv.egiz.eaaf.core.exceptions.EAAFJsonMapperException;

public class JsonMapper implements IJsonMapper {
	private static final Logger log = LoggerFactory.getLogger(JsonMapper.class);
	
	private final ObjectMapper mapper = new ObjectMapper();
	
	/**
	 * The default constructor where the default pretty printer is disabled.
	 */
	public JsonMapper() {
		this(false);
		
	}
	
	/**
	 * The constructor.
	 * @param prettyPrint enables or disables the default pretty printer
	 */
	public JsonMapper(@NonNull boolean prettyPrint) {
		log.trace("Initializing JSON object-mapper ... ");
		mapper.configure(DeserializationFeature.FAIL_ON_READING_DUP_TREE_KEY, true);
		mapper.configure(DeserializationFeature.FAIL_ON_TRAILING_TOKENS, true);
		mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES , true);
		mapper.setVisibility(PropertyAccessor.ALL, Visibility.NONE);
		mapper.setVisibility(PropertyAccessor.GETTER, Visibility.PUBLIC_ONLY);
		mapper.setVisibility(PropertyAccessor.IS_GETTER, Visibility.PUBLIC_ONLY);
		if (prettyPrint) {
			mapper.enable(SerializationFeature.INDENT_OUTPUT);
		}
				
		log.debug("JSON object-mapper initialized");
		
	}

	
	/* (non-Javadoc)
	 * @at.gv.egiz.eaaf.core.api.utils.IJsonMapper#getMapper()
	 */
	public ObjectMapper getMapper() {
		return mapper;
		
	}
	
	
	/* (non-Javadoc)
	 * @see at.gv.egiz.eaaf.core.api.utils.IJsonMapper#serialize(java.lang.Object)
	 */
	@Override
	public String serialize(Object value) throws EAAFJsonMapperException {
		try {
			return mapper.writeValueAsString(value);
			
		} catch (final JsonProcessingException e) {
			log.warn("JSON mapping FAILED with error: {}", e.getMessage());
			throw new EAAFJsonMapperException(e.getMessage(), e);
			
		}
		
	}

	/* (non-Javadoc)
	 * @see at.gv.egiz.eaaf.core.api.utils.IJsonMapper#deserialize(java.lang.String, java.lang.Class)
	 */
	@Override
	public <T> Object deserialize(String value, Class<T> clazz) throws EAAFJsonMapperException {
		try {					
			if (clazz != null) {
				if (clazz.isAssignableFrom(TypeReference.class))
					return mapper.readValue(value, clazz);					
				else {				
					final JavaType javaType = TypeFactory.defaultInstance().constructType(clazz);
					return mapper.readValue(value, javaType);
					
				}
			
			} else
				return mapper.readValue(value, Object.class);
			
		} catch (final IOException e) {
			log.warn("JSON mapping FAILED with error: {}", e.getMessage());
			throw new EAAFJsonMapperException(e.getMessage(), e);
			
		}
		
	}
	
	@Override
	public <T> Object deserialize(InputStream is, Class<T> clazz) throws EAAFJsonMapperException {
		try {					
			if (clazz != null) {
				if (clazz.isAssignableFrom(TypeReference.class))
					return mapper.readValue(is, clazz);					
				else {				
					final JavaType javaType = TypeFactory.defaultInstance().constructType(clazz);
					return mapper.readValue(is, javaType);
					
				}
			
			} else
				return mapper.readValue(is, Object.class);
			
		} catch (final IOException e) {
			log.warn("JSON mapping FAILED with error: {}", e.getMessage());
			throw new EAAFJsonMapperException(e.getMessage(), e);
			
		}
		
	}
							
}