/*
 * Copyright (2023) The Delta Lake Project Authors.
 *
 * 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 io.delta.kernel.defaults.internal.parquet;

import java.util.Optional;

import org.apache.parquet.io.api.Converter;
import org.apache.parquet.schema.GroupType;

import io.delta.kernel.data.ColumnVector;
import io.delta.kernel.types.ArrayType;

import io.delta.kernel.defaults.internal.data.vector.DefaultArrayVector;
import static io.delta.kernel.defaults.internal.parquet.ParquetConverters.createConverter;

class ArrayConverter extends RepeatedValueConverter {
    private final ArrayType typeFromClient;

    ArrayConverter(int initialBatchSize, ArrayType typeFromClient, GroupType typeFromFile) {
        super(
            initialBatchSize,
            createElementConverter(initialBatchSize, typeFromClient, typeFromFile));
        this.typeFromClient = typeFromClient;
    }

    @Override
    public ColumnVector getDataColumnVector(int batchSize) {
        ColumnVector arrayVector = new DefaultArrayVector(
            batchSize,
            typeFromClient,
            Optional.of(getNullability()),
            getOffsets(),
            getElementDataVectors()[0]);
        resetWorkingState();
        return arrayVector;
    }

    private static Converter createElementConverter(
        int initialBatchSize,
        ArrayType typeFromClient,
        GroupType typeFromFile) {

        final GroupType innerElementType = (GroupType) typeFromFile.getType("list");
        return createConverter(
            initialBatchSize,
            typeFromClient.getElementType(),
            innerElementType.getType("element"));
    }
}
