/*
Copyright (c) 2016 Red Hat, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package org.ovirt.engine.api.v3;

import java.io.IOException;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.Request;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;
import javax.ws.rs.core.UriInfo;
import javax.ws.rs.ext.ExceptionMapper;
import javax.ws.rs.ext.Provider;

import org.ovirt.engine.api.utils.InvalidValueException;
import org.ovirt.engine.api.v3.types.V3Fault;
import org.ovirt.engine.api.v3.types.V3UsageMessage;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * This mapper is intended to handle the exceptions thrown by the JAXB message body reader.
 */
@Provider
public class V3IOExceptionMapper implements ExceptionMapper<IOException> {
    private static final Logger log = LoggerFactory.getLogger(V3IOExceptionMapper.class);

    @Context
    protected UriInfo uriInfo;
    @Context
    protected Request request;

    @Override
    public Response toResponse(IOException exception) {
        // Check if the cause of the exception is an invalid value, and generate a specific error message:
        Throwable cause = exception.getCause();
        if (cause instanceof InvalidValueException) {
            V3Fault fault = new V3Fault();
            fault.setReason("Invalid value");
            fault.setDetail(cause.getMessage());
            return Response.status(Status.BAD_REQUEST).entity(fault).build();
        }

        // For any other kind of exception generate an error response with information describing the correct syntax for
        // the request:
        try {
            log.error(
                "IO exception while processing \"{}\" request for path \"{}\"",
                request.getMethod(),
                uriInfo.getPath()
            );
            log.error("Exception", exception);
            V3UsageFinder finder = new V3UsageFinder();
            V3UsageMessage usage = finder.getUsageMessage(uriInfo, request);
            return Response.status(Status.BAD_REQUEST).entity(usage).build();
        }
        catch (Exception error) {
            throw new WebApplicationException(error, Response.status(Status.INTERNAL_SERVER_ERROR).build());
        }
    }
}