/*
 * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, version 2.0, as published by the
 * Free Software Foundation.
 *
 * This program is also distributed with certain software (including but not
 * limited to OpenSSL) that is licensed under separate terms, as designated in a
 * particular file or component or in included license documentation. The
 * authors of MySQL hereby grant you an additional permission to link the
 * program and your derivative works with the separately licensed software that
 * they have included with MySQL.
 *
 * Without limiting anything contained in the foregoing, this file, which is
 * part of MySQL Connector/J, is also subject to the Universal FOSS Exception,
 * version 1.0, a copy of which can be found at
 * http://oss.oracle.com/licenses/universal-foss-exception.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0,
 * for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
 */

package com.mysql.cj.protocol.x;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.function.BiFunction;
import java.util.function.Function;
import java.util.function.Supplier;

import com.mysql.cj.protocol.ColumnDefinition;
import com.mysql.cj.protocol.ResultListener;
import com.mysql.cj.result.BufferedRowList;
import com.mysql.cj.result.Row;
import com.mysql.cj.result.RowList;

/**
 * Create an entire (buffered) result from the data fed to this result listener.
 *
 * @param <RES_T>
 *            The type of result that will be created (and posted to the future)
 */
public class ResultCreatingResultListener<RES_T> implements ResultListener<StatementExecuteOk> {
    private ColumnDefinition metadata;
    private List<Row> rows = new ArrayList<>();
    private Function<ColumnDefinition, BiFunction<RowList, Supplier<StatementExecuteOk>, RES_T>> resultCtor;
    private CompletableFuture<RES_T> future;

    public ResultCreatingResultListener(Function<ColumnDefinition, BiFunction<RowList, Supplier<StatementExecuteOk>, RES_T>> resultCtor,
            CompletableFuture<RES_T> future) {
        this.resultCtor = resultCtor;
        this.future = future;
    }

    public void onMetadata(ColumnDefinition metadataFields) {
        this.metadata = metadataFields;
    }

    public void onRow(Row r) {
        this.rows.add(r);
    }

    public void onComplete(StatementExecuteOk ok) {
        RowList rowList = new BufferedRowList(this.rows);
        RES_T result = this.resultCtor.apply(this.metadata).apply(rowList, () -> ok);
        this.future.complete(result);
    }

    public void onException(Throwable t) {
        this.future.completeExceptionally(t);
    }
}
