package org.gcube.data_catalogue.grsf_publish_ws.utils;

import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.util.List;
import java.util.Map;

import org.gcube.data_catalogue.grsf_publish_ws.custom_annotations.CustomField;
import org.gcube.data_catalogue.grsf_publish_ws.custom_annotations.Group;
import org.gcube.data_catalogue.grsf_publish_ws.custom_annotations.Tag;
import org.gcube.data_catalogue.grsf_publish_ws.json.input.Common;
import org.gcube.datacatalogue.ckanutillibrary.DataCatalogue;
import org.gcube.datacatalogue.ckanutillibrary.DataCatalogueFactory;
import org.slf4j.LoggerFactory;


/**
 * Helper methods
 * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
 */
public abstract class HelperMethods {

	private static final org.slf4j.Logger logger = LoggerFactory.getLogger(HelperMethods.class);

	/**
	 * Convert a group name to its id on ckan
	 * @param origName
	 * @return
	 */
	public static String getGroupNameOnCkan(String origName){

		if(origName == null)
			throw new IllegalArgumentException("origName cannot be null");

		return origName.trim().toLowerCase().replaceAll("[^A-Za-z0-9_.]", "_");

	}

	/**
	 * Retrieve the running instance of the data catalogue for this scope
	 * @return
	 * @throws Exception 
	 */
	public static DataCatalogue getDataCatalogueRunningInstance(String scope) throws Exception{

		return DataCatalogueFactory.getFactory().getUtilsPerScope(scope);

	}

	/**
	 * Retrieve the list of tags for this object
	 */
	public static void getTags(List<String> tags, Common record){
		Class<?> current = record.getClass();
		do{
			Field[] fields = current.getDeclaredFields();
			for (Field field : fields) {
				if(field.isAnnotationPresent(Tag.class)){
					try{
						Object f = new PropertyDescriptor(field.getName(), current).getReadMethod().invoke(record);
						if(f != null){

							tags.add(f.toString());

						}
					}catch(Exception e){
						logger.error("Failed ot read value for field " + field.getName() + " skipping", e);
					}
				}
			}
		}
		while((current = current.getSuperclass())!=null);
	}

	/**
	 * Retrieve the list of groups for this object
	 */
	public static void getGroups(List<String> groups, Common record){
		Class<?> current = record.getClass();
		do{
			Field[] fields = current.getDeclaredFields();
			for (Field field : fields) {
				if(field.isAnnotationPresent(Group.class)){
					try{
						Object f = new PropertyDescriptor(field.getName(), current).getReadMethod().invoke(record);
						if(f != null){

							// also convert to the group name that should be on ckan
							groups.add(getGroupNameOnCkan(f.toString()));

						}
					}catch(Exception e){
						logger.error("Failed ot read value for field " + field.getName() + " skipping", e);
					}
				}
			}
		}
		while((current = current.getSuperclass())!=null);
	}

	/**
	 * Retrieve the list of extras for this object
	 */
	public static void getExtras(Map<String, Object> extras, Common record){
		Class<?> current = record.getClass();
		do{
			Field[] fields = current.getDeclaredFields();
			for (Field field : fields) {
				if(field.isAnnotationPresent(CustomField.class)){
					try{
						Object f = new PropertyDescriptor(field.getName(), current).getReadMethod().invoke(record);
						if(f != null){

							// get the key to put into the map first
							extras.put(field.getAnnotation(CustomField.class).key(), f.toString());

						}
					}catch(Exception e){
						logger.error("Failed ot read value for field " + field.getName() + " skipping", e);
					}
				}
			}
		}
		while((current = current.getSuperclass())!=null);
	}

}