package ejava.examples.ejbwar.inventory.rs;
   
   import javax.inject.Inject;
   import javax.ws.rs.DELETE;
   import javax.ws.rs.DefaultValue;
   import javax.ws.rs.GET;
   import javax.ws.rs.Path;
   import javax.ws.rs.PathParam;
   import javax.ws.rs.Produces;
  import javax.ws.rs.QueryParam;
  import javax.ws.rs.core.Context;
  import javax.ws.rs.core.MediaType;
  import javax.ws.rs.core.Request;
  import javax.ws.rs.core.Response;
  import javax.ws.rs.core.UriInfo;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import ejava.examples.ejbwar.inventory.bo.Categories;
  import ejava.examples.ejbwar.inventory.bo.Category;
  import ejava.examples.ejbwar.inventory.ejb.InventoryMgmtEJB;
  
  /**
   * This class implements a web facade for the product catageories in the 
   * inventory management. It uses JAX-RS to implement the server-side HTTP
   * communications.
   */
  @Path("categories") //part of the method's final URI
  public class CategoriesResource {
  	private static final Logger log = LoggerFactory.getLogger(CategoriesResource.class);
  	
  	@Inject
  	private InventoryMgmtEJB ejb;
  	@Context
  	private Request request;
  	@Context 
  	private UriInfo uriInfo;
  	
  	/**
  	 * This method will respond to a GET of the base resource URI to 
  	 * return categories based on query parameters.
  	 * @param name
  	 * @param offset
  	 * @param limit
  	 * @return
  	 */
  	@GET @Path("")
      @Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
  	public Response findCategoriesByName(
  			@QueryParam("name") @DefaultValue("") String name,
  			@QueryParam("offset") @DefaultValue("0") int offset,
  			@QueryParam("limit") @DefaultValue("0") int limit) {
  		log.debug(String.format("%s %s", request.getMethod(), uriInfo.getAbsolutePath()));
  
  		try {
  			Categories categories = ejb.findCategoryByName(name, offset, limit);
  				//wrap java.lang.List in object that preserves type for marshalling
  			return Response.ok(categories)
  					.build();
  		} catch (Exception ex) {
  			return ResourceHelper.serverError(log, "get categories", ex).build();
  		}
  	}
  	
  	/**
  	 * This method will respond to a GET method for (root)/{id} URIs to get 
  	 * a specific category.
  	 *  
  	 * @param id
  	 * @return
  	 */
  	@GET @Path("{id}")
      @Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
  	public Response getCategory(@PathParam("id")int id) {
  		log.debug(String.format("%s %s", request.getMethod(), uriInfo.getAbsolutePath()));
  
  		try {
  			Category category = ejb.getCategory(id);
  			if (category != null) {
  				return Response.ok(category)
  						.tag("" + category.getVersion())
  						.build();
  			}
  			else {
  				return Response.status(Response.Status.NOT_FOUND)
  						.entity(String.format("unable to locate category %d", id))
  						.type(MediaType.TEXT_PLAIN)
  						.build();
  			}
  		} catch (Exception ex) {
  			return ResourceHelper.serverError(log, "get category", ex).build();
  		}
  	}
  
  	/**
  	 * This method responds to DELETE method calls to (root)/{id} URIs to
  	 * delete a specific category.
  	 * @param id
 	 * @return
 	 */
 	@DELETE @Path("{id}")
 	public Response deleteCategory(@PathParam("id")int id) {
 		log.debug(String.format("%s %s", request.getMethod(), uriInfo.getAbsolutePath()));
 
 		try {
 			ejb.deleteCategory(id);
 			return Response.noContent().build();
 		} catch (Exception ex) {
 			return ResourceHelper.serverError(log, "delete category", ex).build();
 		}
 	}
 
 }