/* Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */

parcel Lucy;

/** Element of a SortSpec.
 *
 * SortRules are the building blocks used to assemble
 * L<SortSpecs|Lucy::Search::SortSpec>; each SortRule defines a single
 * level of sorting.  For example, sorting first by "category" then by score
 * requires a SortSpec with two SortRule elements.
 */
class Lucy::Search::SortRule inherits Lucy::Object::Obj {

    int32_t   type;
    CharBuf  *field;
    bool_t    reverse;

    inert int32_t FIELD;
    inert int32_t SCORE;
    inert int32_t DOC_ID;

    public inert incremented SortRule*
    new(int32_t type = 0, const CharBuf *field = NULL,
        bool_t reverse = false);

    /**
     * @param type Indicate whether to sort by score, field, etc.  (The
     * default is to sort by a field.)
     * @param field The name of a <code>sortable</code> field.
     * @param reverse If true, reverse the order of the sort for this rule.
     */
    public inert incremented SortRule*
    init(SortRule *self, int32_t type = 0, const CharBuf *field = NULL,
         bool_t reverse = false);

    /** Accessor for "field" member.
     */
    public nullable CharBuf*
    Get_Field(SortRule *self);

    /** Accessor for "type" member.
     */
    public int32_t
    Get_Type(SortRule *self);

    /** Accessor for "reverse" member.
     */
    public bool_t
    Get_Reverse(SortRule *self);

    public incremented SortRule*
    Deserialize(SortRule *self, InStream *instream);

    public void
    Serialize(SortRule *self, OutStream *outstream);

    public void
    Destroy(SortRule *self);
}