package net.onrc.onos.core.registry.web;

import java.util.ArrayList;
import java.util.Collection;

import net.onrc.onos.core.registry.IControllerRegistryService;
import net.onrc.onos.core.registry.RegistryException;

import org.restlet.resource.Get;
import org.restlet.resource.ServerResource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ControllerRegistryResource extends ServerResource {

    private static final Logger log = LoggerFactory.getLogger(ControllerRegistryResource.class);

    @Get("json")
    public Collection<String> getControllers() {
        IControllerRegistryService registry =
                (IControllerRegistryService) getContext().getAttributes().
                        get(IControllerRegistryService.class.getCanonicalName());

        Collection<String> controllers = null;
        try {
            controllers = registry.getAllControllers();
        } catch (RegistryException e) {
            log.warn("Error retrieving controller list: {}", e.getMessage());
        }

        if (controllers == null) {
            controllers = new ArrayList<String>();
        }

        return controllers;
    }

}