dnet-core/dnet-core-components/src/main/java/eu/dnetlib/enabling/tools/SplittedQueryExecutor.java

package eu.dnetlib.enabling.tools;

import java.util.List;
import java.util.Map;

import org.springframework.beans.factory.annotation.Required;

import com.google.common.collect.Lists;

import eu.dnetlib.enabling.is.lookup.rmi.ISLookUpDocumentNotFoundException;
import eu.dnetlib.enabling.is.lookup.rmi.ISLookUpException;
import eu.dnetlib.enabling.is.lookup.rmi.ISLookUpService;
import eu.dnetlib.enabling.locators.UniqueServiceLocator;
import eu.dnetlib.miscutils.collections.PositionalStringMapGenerator;

/**
 * Utility class which interacts with a lookup, performs a query and fills a java domain object splitting the result into constructor
 * arguments.
 * 
 * @author marko
 * 
 */
public class SplittedQueryExecutor {

	/**
	 * service locator.
	 */
	private UniqueServiceLocator serviceLocator;

	/**
	 * default constructor. lookupLocator has to be injected.
	 */
	public SplittedQueryExecutor() {
		// empty
	}

	/**
	 * Commodity constructor for constructor injection.
	 * 
	 * @param lookupLocator
	 *            lookup locator
	 */
	public SplittedQueryExecutor(final UniqueServiceLocator serviceLocator) {
		super();
		this.serviceLocator = serviceLocator;
	}

	/**
	 * Performs the query, splits the result at ":-:".
	 * 
	 * @param <X>
	 *            domain class type
	 * @param clazz
	 *            domain class
	 * @param query
	 *            xquery
	 * @return iterable of domain class instances
	 */
	public <X> Iterable<X> query(final Class<X> clazz, final String query) {
		return query(clazz, query, ":-:");
	}

	/**
	 * Performs the query, splits the result at separator
	 * 
	 * @param <X>
	 *            domain class type
	 * @param clazz
	 *            domain class
	 * @param query
	 *            xquery
	 * @param separator
	 *            split separator
	 * @return iterable of domain class instances
	 */
	public <X> Iterable<X> query(final Class<X> clazz, final String query, final String separator) {
		return new PositionalStringMapGenerator<String>().split(clazz, performQuery(query), separator);
	}

	/**
	 * Return a list of maps of splitted query results
	 * 
	 * @param query
	 *            xquery
	 * @param keys
	 *            list of keys
	 * @return collection of key/value pairs
	 */
	public Iterable<Map<String, String>> query(final String query, final String... keys) {
		return new PositionalStringMapGenerator<String>(keys).split(performQuery(query), ":-:");
	}

	/**
	 * Like query(String, String..) but returns a container that whose values can be modified.
	 * 
	 * @param query
	 *            xquery
	 * @param keys
	 *            list of keys
	 * @return mutable collection of key/value pairs
	 */
	public Iterable<Map<String, String>> mutableQuery(final String query, final String... keys) {
		return Lists.newArrayList(query(query, keys));
	}

	/**
	 * Like query(Class, String), but returns a container which can be modified.
	 * 
	 * @param <X>
	 *            some domain class
	 * @param clazz
	 *            domain class
	 * @param query
	 *            xquery
	 * @return mutable collection of X
	 */
	public <X> Iterable<X> mutableQuery(final Class<X> clazz, final String query) {
		return Lists.newArrayList(query(clazz, query));
	}

	/**
	 * Like query(Class, String, String), but returns a container which can be modified.
	 * 
	 * @param <X>
	 *            some domain class
	 * @param clazz
	 *            domain class
	 * @param query
	 *            xquery
	 * @param separator
	 *            separator
	 * @return mutable collection of X
	 */
	public <X> Iterable<X> mutableQuery(final Class<X> clazz, final String query, final String separator) {
		return Lists.newArrayList(query(clazz, query, separator));
	}

	public List<String> performQuery(final String query) {
		try {
			return serviceLocator.getService(ISLookUpService.class).quickSearchProfile(query);
		} catch (final ISLookUpException e) {
			throw new IllegalStateException(e);
		}
	}

	/**
	 * Fetch only one string result.
	 * 
	 * @param query
	 * @return null if no such result
	 */
	public String queryFirst(final String query) {
		try {
			return serviceLocator.getService(ISLookUpService.class).getResourceProfileByQuery(query);
		} catch (ISLookUpDocumentNotFoundException e) {
			return null;
		} catch (final ISLookUpException e) {
			throw new IllegalStateException(e);
		}

	}

	public UniqueServiceLocator getServiceLocator() {
		return serviceLocator;
	}

	@Required
	public void setServiceLocator(final UniqueServiceLocator serviceLocator) {
		this.serviceLocator = serviceLocator;
	}
}