/*
 * Copyright (c) 2014 Brocade Communications Systems, Inc. and others.  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.controller.sal.restconf.impl;

import java.util.List;

import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Response.Status;

import org.opendaylight.controller.sal.restconf.impl.RestconfError.ErrorTag;
import org.opendaylight.controller.sal.restconf.impl.RestconfError.ErrorType;

import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;

/**
 * Unchecked exception to communicate error information, as defined in the ietf restcong draft,
 * to be sent to the client.
 *
 * @author Devin Avery
 * @author Thomas Pantelis
 * @see {@link https://tools.ietf.org/html/draft-bierman-netconf-restconf-02}
 */
public class RestconfDocumentedException extends WebApplicationException {

    private static final long serialVersionUID = 1L;

    private final List<RestconfError> errors;
    private final Status status;

    /**
     * Constructs an instance with an error message. The error type defaults to APPLICATION and
     * the error tag defaults to OPERATION_FAILED.
     *
     * @param message A string which provides a plain text string describing the error.
     */
    public RestconfDocumentedException( String message ) {
        this( message, RestconfError.ErrorType.APPLICATION, RestconfError.ErrorTag.OPERATION_FAILED );
    }

    /**
     * Constructs an instance with an error message, error type, and error tag.
     *
     * @param message A string which provides a plain text string describing the error.
     * @param errorType The enumerated type indicating the layer where the error occurred.
     * @param errorTag The enumerated tag representing a more specific error cause.
     */
    public RestconfDocumentedException( String message, ErrorType errorType, ErrorTag errorTag ) {
        this( null, new RestconfError( errorType, errorTag, message ) );
    }

    /**
     * Constructs an instance with an error message and exception cause. The stack trace of the
     * exception is included in the error info.
     *
     * @param message A string which provides a plain text string describing the error.
     * @param cause The underlying exception cause.
     */
    public RestconfDocumentedException( String message, Throwable cause ) {
        this( cause, new RestconfError( RestconfError.ErrorType.APPLICATION,
                                        RestconfError.ErrorTag.OPERATION_FAILED, message,
                                        null, RestconfError.toErrorInfo( cause ) ) );
    }

    /**
     * Constructs an instance with the given error.
     */
    public RestconfDocumentedException( RestconfError error ) {
        this( null, error );
    }

    /**
     * Constructs an instance with the given errors.
     */
    public RestconfDocumentedException( List<RestconfError> errors ) {
        this.errors = ImmutableList.copyOf( errors );
        Preconditions.checkArgument( !this.errors.isEmpty(), "RestconfError list can't be empty" );
        status = null;
    }

    /**
     * Constructs an instance with an HTTP status and no error information.
     *
     * @param status the HTTP status.
     */
    public RestconfDocumentedException( Status status ) {
        Preconditions.checkNotNull( status, "Status can't be null" );
        errors = ImmutableList.of();
        this.status = status;
    }

    private RestconfDocumentedException( Throwable cause, RestconfError error ) {
        super( cause );
        Preconditions.checkNotNull( error, "RestconfError can't be null" );
        errors = ImmutableList.of( error );
        status = null;
    }

    public List<RestconfError> getErrors() {
        return errors;
    }

    public Status getStatus() {
        return status;
    }


    @Override
    public String getMessage() {
        return "errors: " + errors + (status != null ? ", status: " + status : "");
    }
}