/*
    * Copyright (c) 2014 Cisco Systems, Inc.  All rights reserved.
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Public License v1.0 which accompanies this distribution,
    * and is available at http://www.eclipse.org/legal/epl-v10.html
    */
   
   package org.opendaylight.lispflowmapping.neutron;
  
  import java.net.HttpURLConnection;
  
  import org.apache.commons.lang3.exception.ExceptionUtils;
  import org.opendaylight.lispflowmapping.lisp.util.LispAddressUtil;
  import org.opendaylight.neutron.spi.INeutronSubnetAware;
  import org.opendaylight.neutron.spi.NeutronSubnet;
  import org.opendaylight.yang.gen.v1.urn.opendaylight.lfm.lisp.proto.rev151105.eid.container.Eid;
  
  /**
   * Lisp Service implementation of NeutronSubnetAware API Creation of a new
   * Subnet results in defining the subnet as an EID prefix in the LISP Mapping
   * System with subnet's network UUID as the key to use for registering mappings
   * for the subnet.
   *
   * @author Vina Ermagan
   *
   */
  public class LispNeutronSubnetHandler extends LispNeutronService implements
  		INeutronSubnetAware {
  	private static final Integer SIX = Integer.valueOf(6);
  
  	// The implementation for each of these services is resolved by the OSGi
  	// Service Manager
  	private volatile ILispNeutronService lispNeutronService;
  
  	@Override
  	public int canCreateSubnet(NeutronSubnet subnet) {
  		LOG.info("Neutron canCreateSubnet : Subnet name: " + subnet.getName()
  				+ " Subnet Cidr: " + subnet.getCidr());
  		LOG.debug("Lisp Neutron Subnet: " + subnet.toString());
  		if (SIX.equals(subnet.getIpVersion())) {
  			return HttpURLConnection.HTTP_PARTIAL;
  		}
  		return HttpURLConnection.HTTP_OK;
  	}
  
  	/**
  	 * Method adds the newly created subnet as an EID prefix to the
  	 * MappingService. The subnet's network UUID is used as the key for this EID
  	 * prefix.
  	 *
  	 */
  	@Override
  	public void neutronSubnetCreated(NeutronSubnet subnet) {
  		// TODO update for multi-tenancy
  
  		LOG.info("Neutron Subnet Created request : Subnet name: "
  				+ subnet.getName() + " Subnet Cidr: " + subnet.getCidr());
  		LOG.debug("Lisp Neutron Subnet: " + subnet.toString());
  
  		// Determine the IANA code for the subnet IP version
  		// Default is set to IPv4 for neutron subnets
  
  		Eid eid = LispAddressUtil.asIpv4PrefixEid(subnet.getCidr());
  
  		try {
  
  		    lispNeutronService.getMappingDbService().addKey(LispUtil.buildAddKeyInput(eid, subnet.getNetworkUUID()));
  
  			LOG.debug("Neutron Subnet Added to MapServer : Subnet name: "
  					+ subnet.getName() + " EID Prefix: "
  					+ subnet.getCidr() + " Key: "
  					+ subnet.getNetworkUUID());
  		} catch (Exception e) {
  			LOG.error("Adding new subnet to lisp service mapping service failed. Subnet : "
  					+ subnet.toString() + "Error: " + ExceptionUtils.getStackTrace(e));
  		}
          LOG.info("Neutron Subnet Created request : Subnet name: "
                  + subnet.getName() + " Subnet Cidr: " + subnet.getCidr());
  
  	}
  
  	/**
  	 * Method to check whether new Subnet can be created by LISP implementation
  	 * of Neutron service API. Since we store the Cidr part of the subnet as the
  	 * main key to the Lisp mapping service, we do not support updates to
  	 * subnets that change it's cidr.
  	 */
  	@Override
  	public int canUpdateSubnet(NeutronSubnet delta, NeutronSubnet original) {
  		if (delta == null || original == null) {
  			LOG.error("Neutron canUpdateSubnet rejected: subnet objects were null");
  			return HttpURLConnection.HTTP_BAD_REQUEST;
  		}
  		LOG.info("Neutron canUpdateSubnet : Subnet name: " + original.getName()
  				+ " Subnet Cidr: " + original.getCidr());
  		LOG.debug("Lisp Neutron Subnet update: original : "
  				+ original.toString() + " delta : " + delta.toString());
  
 		// We do not accept a Subnet update that changes the cidr. If cider or
 		// network UUID is changed, return error.
 		if (!(original.getCidr().equals(delta.getCidr()))) {
 			LOG.error("Neutron canUpdateSubnet rejected: Subnet name: "
 					+ original.getName() + " Subnet Cidr: "
 					+ original.getCidr());
 			return HttpURLConnection.HTTP_CONFLICT;
 		}
 		return HttpURLConnection.HTTP_OK;
 	}
 
 	@Override
 	public void neutronSubnetUpdated(NeutronSubnet subnet) {
 		// Nothing to do here.
 	}
 
 	/**
 	 * Method to check if subnet can be deleted. Returns error only if subnet
 	 * does not exist in the lisp mapping service.
 	 */
 	@Override
 	public int canDeleteSubnet(NeutronSubnet subnet) {
 		LOG.info("Neutron canDeleteSubnet : Subnet name: " + subnet.getName()
 				+ " Subnet Cidr: " + subnet.getCidr() + "Key: "
 				+ subnet.getNetworkUUID());
 		LOG.debug("Lisp Neutron Subnet: " + subnet.toString());
 
 
 			return HttpURLConnection.HTTP_OK;
 	}
 
 	/**
 	 * Method removes the EID prefix and key associated with the deleted subnet
 	 * from Lisp mapping service.
 	 */
 	@Override
 	public void neutronSubnetDeleted(NeutronSubnet subnet) {
 		LOG.info("Neutron Subnet Deleted Request : Subnet name: "
 				+ subnet.getName() + " Subnet Cidr: " + subnet.getCidr()
 				+ "Key: " + subnet.getNetworkUUID());
 		LOG.debug("Lisp Neutron Subnet: " + subnet.toString());
 
 		// Determine the IANA code for the subnet IP version
 		// Default is set to IPv4 for neutron subnets
 
 		Eid eid = LispAddressUtil.asIpv4PrefixEid(subnet.getCidr());
 
         try {
 
             lispNeutronService.getMappingDbService().removeKey(LispUtil.buildRemoveKeyInput(eid));
 
 			LOG.debug("Neutron Subnet Deleted from MapServer : Subnet name: "
 					+ subnet.getName() + " Eid Prefix: "
 					+ subnet.getCidr() + " Key: "
 					+ subnet.getNetworkUUID());
 		} catch (Exception e) {
 			LOG.error("Deleting subnet's EID prefix from mapping service failed + Subnet: "
 					+ subnet.toString() + "Error: " + ExceptionUtils.getStackTrace(e));
 		}
 	}
 
 }