/**
 * ============LICENSE_START=======================================================
 * org.onap.aai
 * ================================================================================
 * Copyright © 2017-2018 AT&T Intellectual Property. All rights reserved.
 * Copyright © 2017-2018 Amdocs
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 */
package org.onap.aai.sa.searchdbabstraction.searchapi;

import java.util.ArrayList;
import java.util.List;

/**
 * This class represents the filter stanza in a search statement.
 *
 * <p>
 * The expected JSON structure for a filter stanza is as follows:
 *
 * <pre>
 * {
 *     "filter": {
 *        "all": [ {query structure}, {query structure}, ... {query structure} ],
 *        "any": [ {query structure}, {query structure}, ... {query structure} ]
 *     }
 * }
 * </pre>
 */
public class Filter {

    /**
     * All queries in this list must evaluate to true for the filter to pass.
     */
    private QueryStatement[] all;

    /**
     * Any one of the queries in this list must evaluate to true for the filter to pass.
     */
    private QueryStatement[] any;


    public QueryStatement[] getAll() {
        return all;
    }

    public void setAll(QueryStatement[] all) {
        this.all = all;
    }

    public QueryStatement[] getAny() {
        return any;
    }

    public void setAny(QueryStatement[] any) {
        this.any = any;
    }

    /**
     * This method returns a string which represents this filter in syntax that is understandable by ElasticSearch and
     * is suitable for inclusion in an ElasticSearch query string.
     *
     * @return - ElasticSearch syntax string.
     */
    public String toElasticSearch() {

        StringBuilder sb = new StringBuilder();

        List<QueryStatement> notMatchQueries = new ArrayList<>();
        sb.append("{");
        sb.append("\"bool\": {");

        // Add the queries from our 'all' list.
        int matchQueriesCount = 0;
        int notMatchQueriesCount = 0;
        if (all != null) {
            sb.append("\"must\": [");

            for (QueryStatement query : all) {
                if (matchQueriesCount > 0) {
                    sb.append(", ");
                }

                if (query.isNotMatch()) {
                    notMatchQueries.add(query);
                } else {
                    sb.append(query.toElasticSearch());
                    matchQueriesCount++;
                }
            }
            sb.append("],");


            sb.append("\"must_not\": [");
            for (QueryStatement query : notMatchQueries) {
                if (notMatchQueriesCount > 0) {
                    sb.append(", ");
                }
                sb.append(query.toElasticSearch());
                notMatchQueriesCount++;
            }
            sb.append("]");
        }

        // Add the queries from our 'any' list.
        notMatchQueries.clear();
        if (any != null) {
            if (all != null) {
                sb.append(",");
            }
            sb.append("\"should\": [");

            matchQueriesCount = 0;
            for (QueryStatement query : any) {
                if (matchQueriesCount > 0) {
                    sb.append(", ");
                }

                if (query.isNotMatch()) {
                    notMatchQueries.add(query);
                } else {
                    sb.append(query.toElasticSearch());
                    matchQueriesCount++;
                }
            }
            sb.append("],");

            notMatchQueriesCount = 0;
            sb.append("\"must_not\": [");
            for (QueryStatement query : notMatchQueries) {
                if (notMatchQueriesCount > 0) {
                    sb.append(", ");
                }
                sb.append(query.toElasticSearch());
                notMatchQueriesCount++;
            }
            sb.append("]");
        }
        sb.append("}");
        sb.append("}");

        return sb.toString();
    }

    @Override
    public String toString() {

        StringBuilder sb = new StringBuilder();

        sb.append("{");

        sb.append("all: [");
        if (all != null) {
            for (QueryStatement query : all) {
                sb.append(query.toString());
            }
        }
        sb.append("], ");

        sb.append("any: [");
        if (any != null) {
            for (QueryStatement query : any) {
                sb.append(query.toString());
            }
        }
        sb.append("] ");

        sb.append("}");

        return sb.toString();
    }
}