/*
 * Copyright (C) 2014 SDN Hub, LLC.
 *
 * 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
 *
 * Authors : Srini Seetharaman
 */

package org.opendaylight.neutron.northbound.api;

import java.net.HttpURLConnection;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

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.core.MediaType;
import javax.ws.rs.core.Response;

import org.codehaus.enunciate.jaxrs.ResponseCode;
import org.codehaus.enunciate.jaxrs.StatusCodes;
import org.opendaylight.neutron.spi.INeutronLoadBalancerPoolCRUD;
import org.opendaylight.neutron.spi.INeutronLoadBalancerPoolMemberAware;
import org.opendaylight.neutron.spi.NeutronCRUDInterfaces;
import org.opendaylight.neutron.spi.NeutronLoadBalancerPool;
import org.opendaylight.neutron.spi.NeutronLoadBalancerPoolMember;

@Path("/lbaas/pools/{loadBalancerPoolUUID}/members")
public class NeutronLoadBalancerPoolMembersNorthbound {
    private static final int HTTP_OK_BOTTOM = 200;
    private static final int HTTP_OK_TOP = 299;
    private static final String INTERFACE_NAME = "LoadBalancerPool CRUD Interface";
    private static final String UUID_NO_EXIST = "LoadBalancerPool UUID does not exist.";
    private static final String NO_PROVIDERS = "No providers registered.  Please try again later";
    private static final String NO_PROVIDER_LIST = "Couldn't get providers list.  Please try again later";

    private NeutronLoadBalancerPoolMember extractFields(NeutronLoadBalancerPoolMember o, List<String> fields) {
        return o.extractFields(fields);
    }

    private NeutronCRUDInterfaces getNeutronInterfaces() {
        NeutronCRUDInterfaces answer = new NeutronCRUDInterfaces().fetchINeutronLoadBalancerPoolCRUD(this);
        if (answer.getLoadBalancerPoolInterface() == null) {
            throw new ServiceUnavailableException(INTERFACE_NAME
                + RestMessages.SERVICEUNAVAILABLE.toString());
        }
        return answer;
    }

/**
 * Returns a list of all LoadBalancerPoolMembers in specified pool
 */
@GET
@Produces({MediaType.APPLICATION_JSON})
@StatusCodes({
        @ResponseCode(code = HttpURLConnection.HTTP_OK, condition = "Operation successful"),
        @ResponseCode(code = HttpURLConnection.HTTP_UNAUTHORIZED, condition = "Unauthorized"),
        @ResponseCode(code = HttpURLConnection.HTTP_NOT_IMPLEMENTED, condition = "Not Implemented"),
        @ResponseCode(code = HttpURLConnection.HTTP_UNAVAILABLE, condition = "No providers available") })

public Response listMembers(
        //Path param
        @PathParam("loadBalancerPoolUUID") String loadBalancerPoolUUID,

        // return fields
        @QueryParam("fields") List<String> fields,

        // OpenStack LoadBalancerPool attributes
        @QueryParam("id") String queryLoadBalancerPoolMemberID,
        @QueryParam("tenant_id") String queryLoadBalancerPoolMemberTenantID,
        @QueryParam("address") String queryLoadBalancerPoolMemberAddress,
        @QueryParam("protocol_port") String queryLoadBalancerPoolMemberProtoPort,
        @QueryParam("admin_state_up") String queryLoadBalancerPoolMemberAdminStateUp,
        @QueryParam("weight") String queryLoadBalancerPoolMemberWeight,
        @QueryParam("subnet_id") String queryLoadBalancerPoolMemberSubnetID,

        // pagination
        @QueryParam("limit") String limit,
        @QueryParam("marker") String marker,
        @QueryParam("page_reverse") String pageReverse
        // sorting not supported
) {
    INeutronLoadBalancerPoolCRUD loadBalancerPoolInterface = getNeutronInterfaces().getLoadBalancerPoolInterface();
    if (!loadBalancerPoolInterface.neutronLoadBalancerPoolExists(loadBalancerPoolUUID)) {
        throw new ResourceNotFoundException(UUID_NO_EXIST);
    }
    List<NeutronLoadBalancerPoolMember> members =
                loadBalancerPoolInterface.getNeutronLoadBalancerPool(loadBalancerPoolUUID).getLoadBalancerPoolMembers();
    List<NeutronLoadBalancerPoolMember> ans = new ArrayList<NeutronLoadBalancerPoolMember>();
    Iterator<NeutronLoadBalancerPoolMember> i = members.iterator();
    while (i.hasNext()) {
        NeutronLoadBalancerPoolMember nsg = i.next();
        if ((queryLoadBalancerPoolMemberID == null ||
                queryLoadBalancerPoolMemberID.equals(nsg.getPoolMemberID())) &&
                loadBalancerPoolUUID.equals(nsg.getPoolID()) &&
                (queryLoadBalancerPoolMemberTenantID == null ||
                        queryLoadBalancerPoolMemberTenantID.equals(nsg.getPoolMemberTenantID())) &&
                (queryLoadBalancerPoolMemberAddress == null ||
                        queryLoadBalancerPoolMemberAddress.equals(nsg.getPoolMemberAddress())) &&
                (queryLoadBalancerPoolMemberAdminStateUp == null ||
                        queryLoadBalancerPoolMemberAdminStateUp.equals(nsg.getPoolMemberAdminStateIsUp())) &&
                (queryLoadBalancerPoolMemberWeight == null ||
                        queryLoadBalancerPoolMemberWeight.equals(nsg.getPoolMemberWeight())) &&
                (queryLoadBalancerPoolMemberSubnetID == null ||
                        queryLoadBalancerPoolMemberSubnetID.equals(nsg.getPoolMemberSubnetID()))) {
            if (fields.size() > 0) {
                ans.add(extractFields(nsg, fields));
            } else {
                ans.add(nsg);
            }
        }
    }
    return Response.status(HttpURLConnection.HTTP_OK).entity(
            new NeutronLoadBalancerPoolMemberRequest(ans)).build();
}

/**
 * Returns a specific LoadBalancerPoolMember
 */

@Path("{loadBalancerPoolMemberUUID}")
@GET
@Produces({ MediaType.APPLICATION_JSON })
//@TypeHint(OpenStackLoadBalancerPoolMembers.class)
@StatusCodes({
    @ResponseCode(code = HttpURLConnection.HTTP_OK, condition = "Operation successful"),
    @ResponseCode(code = HttpURLConnection.HTTP_UNAUTHORIZED, condition = "Unauthorized"),
    @ResponseCode(code = HttpURLConnection.HTTP_NOT_FOUND, condition = "Not Found"),
    @ResponseCode(code = HttpURLConnection.HTTP_NOT_IMPLEMENTED, condition = "Not Implemented"),
    @ResponseCode(code = HttpURLConnection.HTTP_UNAVAILABLE, condition = "No providers available") })
public Response showLoadBalancerPoolMember(
        @PathParam("loadBalancerPoolUUID") String loadBalancerPoolUUID,
        @PathParam("loadBalancerPoolMemberUUID") String loadBalancerPoolMemberUUID,
        // return fields
        @QueryParam("fields") List<String> fields ) {

    INeutronLoadBalancerPoolCRUD loadBalancerPoolInterface = getNeutronInterfaces().getLoadBalancerPoolInterface();
    if (!loadBalancerPoolInterface.neutronLoadBalancerPoolExists(loadBalancerPoolUUID)) {
        throw new ResourceNotFoundException(UUID_NO_EXIST);
    }
    List<NeutronLoadBalancerPoolMember> members =
                loadBalancerPoolInterface.getNeutronLoadBalancerPool(loadBalancerPoolUUID).getLoadBalancerPoolMembers();
    for (NeutronLoadBalancerPoolMember ans: members) {
        if (!ans.getPoolMemberID().equals(loadBalancerPoolMemberUUID)) {
            continue;
        }

        if (fields.size() > 0) {
            return Response.status(HttpURLConnection.HTTP_OK).entity(
                new NeutronLoadBalancerPoolMemberRequest(extractFields(ans, fields))).build();
        } else {
            return Response.status(HttpURLConnection.HTTP_OK).entity(
                new NeutronLoadBalancerPoolMemberRequest(ans)).build();
        }
    }
    return Response.status(HttpURLConnection.HTTP_NO_CONTENT).build();
}

/**
 * Adds a Member to an LBaaS Pool member
 */
@POST
@Produces({MediaType.APPLICATION_JSON})
@Consumes({MediaType.APPLICATION_JSON})
@StatusCodes({
        @ResponseCode(code = HttpURLConnection.HTTP_OK, condition = "Operation successful"),
        @ResponseCode(code = HttpURLConnection.HTTP_UNAUTHORIZED, condition = "Unauthorized"),
        @ResponseCode(code = HttpURLConnection.HTTP_NOT_FOUND, condition = "Not Found"),
        @ResponseCode(code = HttpURLConnection.HTTP_NOT_IMPLEMENTED, condition = "Not Implemented"),
        @ResponseCode(code = HttpURLConnection.HTTP_UNAVAILABLE, condition = "No providers available") })
public Response createLoadBalancerPoolMember(
        @PathParam("loadBalancerPoolUUID") String loadBalancerPoolUUID,
        final NeutronLoadBalancerPoolMemberRequest input) {

    INeutronLoadBalancerPoolCRUD loadBalancerPoolInterface = getNeutronInterfaces().getLoadBalancerPoolInterface();
    // Verify that the loadBalancerPool exists, for the member to be added to its cache
    if (!loadBalancerPoolInterface.neutronLoadBalancerPoolExists(loadBalancerPoolUUID)) {
        throw new ResourceNotFoundException(UUID_NO_EXIST);
    }
    NeutronLoadBalancerPool singletonPool = loadBalancerPoolInterface.getNeutronLoadBalancerPool(loadBalancerPoolUUID);

    if (input.isSingleton()) {
        NeutronLoadBalancerPoolMember singleton = input.getSingleton();
        singleton.setPoolID(loadBalancerPoolUUID);
        String loadBalancerPoolMemberUUID = singleton.getPoolMemberID();

        /*
         *  Verify that the LoadBalancerPoolMember doesn't already exist.
         */
        if (singletonPool.getLoadBalancerPoolMembers() != null) {
            List<NeutronLoadBalancerPoolMember> members = singletonPool.getLoadBalancerPoolMembers();
            for (NeutronLoadBalancerPoolMember member: members) {
                if (member.getPoolMemberID().equals(loadBalancerPoolMemberUUID)) {
                    throw new BadRequestException("LoadBalancerPoolMember UUID already exists");
                }
            }
        }

        Object[] instances = NeutronUtil.getInstances(INeutronLoadBalancerPoolMemberAware.class, this);
        if (instances != null) {
            if (instances.length > 0) {
                for (Object instance : instances) {
                    INeutronLoadBalancerPoolMemberAware service = (INeutronLoadBalancerPoolMemberAware) instance;
                    int status = service.canCreateNeutronLoadBalancerPoolMember(singleton);
                    if (status < HTTP_OK_BOTTOM || status > HTTP_OK_TOP) {
                        return Response.status(status).build();
                    }
                }
            } else {
                throw new ServiceUnavailableException(NO_PROVIDERS);
            }
        } else {
            throw new ServiceUnavailableException(NO_PROVIDER_LIST);
        }

        if (instances != null) {
            for (Object instance : instances) {
                INeutronLoadBalancerPoolMemberAware service = (INeutronLoadBalancerPoolMemberAware) instance;
                service.neutronLoadBalancerPoolMemberCreated(singleton);
            }
        }

        /**
         * Add the member from the neutron load balancer pool as well
         */
        singletonPool.addLoadBalancerPoolMember(singleton);

    } else {
        List<NeutronLoadBalancerPoolMember> bulk = input.getBulk();
        Iterator<NeutronLoadBalancerPoolMember> i = bulk.iterator();
        Map<String, NeutronLoadBalancerPoolMember> testMap = new HashMap<String, NeutronLoadBalancerPoolMember>();
        Object[] instances = NeutronUtil.getInstances(INeutronLoadBalancerPoolMemberAware.class, this);
        while (i.hasNext()) {
            NeutronLoadBalancerPoolMember test = i.next();
            String loadBalancerPoolMemberUUID = test.getPoolMemberID();

            /*
             *  Verify that the LoadBalancerPoolMember doesn't already exist.
             */
            List<NeutronLoadBalancerPoolMember> members = singletonPool.getLoadBalancerPoolMembers();
            for (NeutronLoadBalancerPoolMember member: members) {
                if (member.getPoolMemberID().equals(loadBalancerPoolMemberUUID)) {
                    throw new BadRequestException("LoadBalancerPoolMember UUID already exists");
                }
            }

            if (testMap.containsKey(test.getPoolMemberID())) {
                throw new BadRequestException("Load Balancer PoolMember UUID already exists");
            }
            if (instances != null) {
                if (instances.length > 0) {
                    for (Object instance : instances) {
                        INeutronLoadBalancerPoolMemberAware service = (INeutronLoadBalancerPoolMemberAware) instance;
                        int status = service.canCreateNeutronLoadBalancerPoolMember(test);
                        if (status < HTTP_OK_BOTTOM || status > HTTP_OK_TOP) {
                            return Response.status(status).build();
                        }
                    }
                } else {
                    throw new ServiceUnavailableException(NO_PROVIDERS);
                }
            } else {
                throw new ServiceUnavailableException(NO_PROVIDER_LIST);
            }
        }
        /*
         * now, each element of the bulk request can be added to the cache
         */
        i = bulk.iterator();
        while (i.hasNext()) {
            NeutronLoadBalancerPoolMember test = i.next();
            if (instances != null) {
                for (Object instance : instances) {
                    INeutronLoadBalancerPoolMemberAware service = (INeutronLoadBalancerPoolMemberAware) instance;
                    service.neutronLoadBalancerPoolMemberCreated(test);
                }
            }
            singletonPool.addLoadBalancerPoolMember(test);
        }
    }
    return Response.status(HttpURLConnection.HTTP_CREATED).entity(input).build();
}

/**
 * Updates a LB member pool
 */

@Path("{loadBalancerPoolMemberUUID}")
@PUT
@Produces({ MediaType.APPLICATION_JSON })
@Consumes({ MediaType.APPLICATION_JSON })
@StatusCodes({
        @ResponseCode(code = HttpURLConnection.HTTP_OK, condition = "Operation successful"),
        @ResponseCode(code = HttpURLConnection.HTTP_BAD_REQUEST, condition = "Bad Request"),
        @ResponseCode(code = HttpURLConnection.HTTP_UNAUTHORIZED, condition = "Unauthorized"),
        @ResponseCode(code = HttpURLConnection.HTTP_FORBIDDEN, condition = "Forbidden"),
        @ResponseCode(code = HttpURLConnection.HTTP_NOT_FOUND, condition = "Not Found"),
        @ResponseCode(code = HttpURLConnection.HTTP_NOT_IMPLEMENTED, condition = "Not Implemented") })
public Response updateLoadBalancerPoolMember(
        @PathParam("loadBalancerPoolUUID") String loadBalancerPoolUUID,
        @PathParam("loadBalancerPoolMemberUUID") String loadBalancerPoolMemberUUID,
        final NeutronLoadBalancerPoolMemberRequest input) {

    //TODO: Implement update LB member pool
    return Response.status(HttpURLConnection.HTTP_NOT_IMPLEMENTED).entity(input).build();
}

/**
 * Deletes a LoadBalancerPoolMember
 */

@Path("{loadBalancerPoolMemberUUID}")
@DELETE
@StatusCodes({
    @ResponseCode(code = HttpURLConnection.HTTP_NO_CONTENT, condition = "No Content"),
    @ResponseCode(code = HttpURLConnection.HTTP_UNAUTHORIZED, condition = "Unauthorized"),
    @ResponseCode(code = HttpURLConnection.HTTP_FORBIDDEN, condition = "Forbidden"),
    @ResponseCode(code = HttpURLConnection.HTTP_NOT_FOUND, condition = "Not Found"),
    @ResponseCode(code = HttpURLConnection.HTTP_NOT_IMPLEMENTED, condition = "Not Implemented"),
    @ResponseCode(code = HttpURLConnection.HTTP_UNAVAILABLE, condition = "No providers available") })
public Response deleteLoadBalancerPoolMember(
        @PathParam("loadBalancerPoolUUID") String loadBalancerPoolUUID,
        @PathParam("loadBalancerPoolMemberUUID") String loadBalancerPoolMemberUUID) {
    INeutronLoadBalancerPoolCRUD loadBalancerPoolInterface = getNeutronInterfaces().getLoadBalancerPoolInterface();

    // Verify that the loadBalancerPool exists, for the member to be removed from its cache
    if (!loadBalancerPoolInterface.neutronLoadBalancerPoolExists(loadBalancerPoolUUID)) {
        throw new ResourceNotFoundException(UUID_NO_EXIST);
    }

    //Verify that the LB pool member exists
    NeutronLoadBalancerPoolMember singleton = null;
    List<NeutronLoadBalancerPoolMember> members =
            loadBalancerPoolInterface.getNeutronLoadBalancerPool(loadBalancerPoolUUID).getLoadBalancerPoolMembers();
    for (NeutronLoadBalancerPoolMember member: members) {
        if (member.getPoolMemberID().equals(loadBalancerPoolMemberUUID)) {
            singleton = member;
            break;
        }
    }
    if (singleton == null) {
        throw new BadRequestException("LoadBalancerPoolMember UUID does not exist.");
    }

    Object[] instances = NeutronUtil.getInstances(INeutronLoadBalancerPoolMemberAware.class, this);
    if (instances != null) {
        if (instances.length > 0) {
            for (Object instance : instances) {
                INeutronLoadBalancerPoolMemberAware service = (INeutronLoadBalancerPoolMemberAware) instance;
                int status = service.canDeleteNeutronLoadBalancerPoolMember(singleton);
                if (status < HTTP_OK_BOTTOM || status > HTTP_OK_TOP) {
                    return Response.status(status).build();
                }
            }
        } else {
            throw new ServiceUnavailableException(NO_PROVIDERS);
        }
    } else {
        throw new ServiceUnavailableException(NO_PROVIDER_LIST);
    }

    if (instances != null) {
        for (Object instance : instances) {
            INeutronLoadBalancerPoolMemberAware service = (INeutronLoadBalancerPoolMemberAware) instance;
            service.neutronLoadBalancerPoolMemberDeleted(singleton);
        }
    }

    /**
     * Remove the member from the neutron load balancer pool
     */
    NeutronLoadBalancerPool singletonPool = loadBalancerPoolInterface.getNeutronLoadBalancerPool(loadBalancerPoolUUID);
    singletonPool.removeLoadBalancerPoolMember(singleton);

    return Response.status(HttpURLConnection.HTTP_NO_CONTENT).build();
}
}