/********************************************************************************
 * Copyright (c) 2015-2018 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 ********************************************************************************/

package org.eclipse.mdm.businessobjects.boundary;

import static org.eclipse.mdm.businessobjects.boundary.ResourceConstants.ENTITYATTRIBUTE_NAME;
import static org.eclipse.mdm.businessobjects.boundary.ResourceConstants.ENTITYATTRIBUTE_PHYSICALDIMENSION_ID;
import static org.eclipse.mdm.businessobjects.boundary.ResourceConstants.REQUESTPARAM_ID;
import static org.eclipse.mdm.businessobjects.boundary.ResourceConstants.REQUESTPARAM_SOURCENAME;
import static org.eclipse.mdm.businessobjects.service.EntityService.L;
import static org.eclipse.mdm.businessobjects.service.EntityService.V;

import javax.ejb.EJB;
import javax.ws.rs.Consumes;
import javax.ws.rs.DELETE;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.PUT;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;

import org.eclipse.mdm.api.base.model.Environment;
import org.eclipse.mdm.api.base.model.PhysicalDimension;
import org.eclipse.mdm.api.base.model.Unit;
import org.eclipse.mdm.businessobjects.entity.SearchAttribute;
import org.eclipse.mdm.businessobjects.service.EntityService;
import org.eclipse.mdm.businessobjects.utils.RequestBody;
import org.eclipse.mdm.businessobjects.utils.ServiceUtils;

/**
 * {@link Unit} resource handling REST requests
 * 
 * @author Alexander Nehmer, science+computing AG Tuebingen (Atos SE)
 *
 */
@Path("/environments/{" + REQUESTPARAM_SOURCENAME + "}/units")
public class UnitResource {

	@EJB
	private EntityService entityService;

	/**
	 * Returns the found {@link Unit}. {@link WebApplicationException} on error.
	 * 
	 * @param sourceName
	 *            name of the source (MDM {@link Environment} name)
	 * @param id
	 *            id of the {@link Unit}
	 * @return the found {@link Unit} as {@link Response}
	 */
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	@Path("/{" + REQUESTPARAM_ID + "}")
	public Response find(@PathParam(REQUESTPARAM_SOURCENAME) String sourceName, @PathParam(REQUESTPARAM_ID) String id) {
		return entityService.find(V(sourceName), Unit.class, V(id))
				.map(e -> ServiceUtils.buildEntityResponse(e, Status.OK))
				.recover(ServiceUtils.ERROR_RESPONSE_SUPPLIER)
				.getOrElse(ServiceUtils.SERVER_ERROR_RESPONSE);
	}

	/**
	 * Returns the (filtered) {@link Unit}s.
	 * 
	 * 
	 * @param sourceName
	 *            name of the source (MDM {@link Environment} name)
	 * @param filter
	 *            filter string to filter the {@link Unit} result
	 * @return the (filtered) {@link Unit}s as {@link Response}
	 */
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public Response findAll(@PathParam(REQUESTPARAM_SOURCENAME) String sourceName,
			@QueryParam("filter") String filter) {
		return entityService.findAll(V(sourceName), Unit.class, filter)
				.map(e -> ServiceUtils.buildEntityResponse(e, Status.OK))
				.recover(ServiceUtils.ERROR_RESPONSE_SUPPLIER)
				.getOrElse(ServiceUtils.SERVER_ERROR_RESPONSE);
	}

	/**
	 * Returns the created {@link Unit}.
	 * 
	 * 
	 * @param body
	 *            The {@link Unit} to create.
	 * @return the created {@link Unit} as {@link Response}.
	 */
	@POST
	@Produces(MediaType.APPLICATION_JSON)
	@Consumes(MediaType.APPLICATION_JSON)
	public Response create(@PathParam(REQUESTPARAM_SOURCENAME) String sourceName, String body) {
		RequestBody requestBody = RequestBody.create(body);

		return entityService
				.create(V(sourceName), Unit.class, L(requestBody.getStringValueSupplier(ENTITYATTRIBUTE_NAME),
						entityService.find(V(sourceName), PhysicalDimension.class,
								requestBody.getStringValueSupplier(ENTITYATTRIBUTE_PHYSICALDIMENSION_ID))))
				.map(e -> ServiceUtils.buildEntityResponse(e, Status.CREATED))
				.recover(ServiceUtils.ERROR_RESPONSE_SUPPLIER)
				.getOrElse(ServiceUtils.SERVER_ERROR_RESPONSE);
	}

	/**
	 * Updates the {@link Unit} with all parameters set in the given JSON body of
	 * the request.
	 * 
	 * @param sourceName
	 *            name of the source (MDM {@link Environment} name)
	 * @param id
	 *            the identifier of the {@link Unit} to update.
	 * @param body
	 *            the body of the request containing the attributes to update
	 * @return the updated {@link Unit}
	 */
	@PUT
	@Produces(MediaType.APPLICATION_JSON)
	@Consumes(MediaType.APPLICATION_JSON)
	@Path("/{" + REQUESTPARAM_ID + "}")
	public Response update(@PathParam(REQUESTPARAM_SOURCENAME) String sourceName, @PathParam(REQUESTPARAM_ID) String id,
			String body) {
		RequestBody requestBody = RequestBody.create(body);

		return entityService
				.update(V(sourceName), entityService.find(V(sourceName), Unit.class, V(id)), requestBody.getValueMapSupplier())
				.map(e -> ServiceUtils.buildEntityResponse(e, Status.OK))
				.recover(ServiceUtils.ERROR_RESPONSE_SUPPLIER)
				.getOrElse(ServiceUtils.SERVER_ERROR_RESPONSE);
	}

	/**
	 * Deletes and returns the deleted {@link Unit}. {@link WebApplicationException}
	 * on error.
	 * 
	 * @param sourceName
	 *            name of the source (MDM {@link Environment} name)
	 * @param id
	 *            The identifier of the {@link Unit} to delete.
	 * @return the deleted {@link Unit }s as {@link Response}
	 */
	@DELETE
	@Produces(MediaType.APPLICATION_JSON)
	@Path("/{" + REQUESTPARAM_ID + "}")
	public Response delete(@PathParam(REQUESTPARAM_SOURCENAME) String sourceName,
			@PathParam(REQUESTPARAM_ID) String id) {
		return entityService.delete(V(sourceName), entityService.find(V(sourceName), Unit.class, V(id)))
				.map(e -> ServiceUtils.buildEntityResponse(e, Status.OK))
				.recover(ServiceUtils.ERROR_RESPONSE_SUPPLIER)
				.getOrElse(ServiceUtils.SERVER_ERROR_RESPONSE);
	}

	/**
	 * Returns the search attributes for the {@link Unit} type.
	 * 
	 * @param sourceName
	 *            name of the source (MDM {@link Environment} name)
	 * @return the {@link SearchAttribute}s as {@link Response}
	 */
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	@Path("/searchattributes")
	public Response getSearchAttributes(@PathParam(REQUESTPARAM_SOURCENAME) String sourceName) {
		return ServiceUtils.buildSearchAttributesResponse(V(sourceName), Unit.class, entityService);
	}

	/**
	 * Returns a map of localization for the entity type and the attributes.
	 * 
	 * @param sourceName
	 *            name of the source (MDM {@link Environment} name)
	 * @return the I18N as {@link Response}
	 */
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	@Path("/localizations")
	public Response localize(@PathParam(REQUESTPARAM_SOURCENAME) String sourceName) {
		return ServiceUtils.buildLocalizationResponse(V(sourceName), Unit.class, entityService);
	}
}