/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [http://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.neo4j.procedure.impl;

import static org.neo4j.internal.kernel.api.procs.DefaultParameterValue.ntList;

import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import java.util.function.Function;
import org.neo4j.cypher.internal.evaluator.EvaluationException;
import org.neo4j.cypher.internal.evaluator.ExpressionEvaluator;
import org.neo4j.internal.kernel.api.procs.DefaultParameterValue;
import org.neo4j.internal.kernel.api.procs.Neo4jTypes;

public class ListConverter implements Function<String, DefaultParameterValue> {
    private final Neo4jTypes.AnyType neoType;
    private final ExpressionEvaluator evaluator;
    private final Type type;

    ListConverter(Type type, Neo4jTypes.AnyType neoType, ExpressionEvaluator evaluator) {
        this.type = type;
        this.neoType = neoType;
        this.evaluator = evaluator;
    }

    @Override
    public DefaultParameterValue apply(String s) {
        try {
            List<?> list = evaluator.evaluate(s, List.class);
            typeCheck(list, type);
            return ntList(list, neoType);
        } catch (EvaluationException e) {
            throw new IllegalArgumentException(String.format("%s is not a valid list expression", s), e);
        }
    }

    private static void typeCheck(List<?> list, Type innerType) {
        if (list == null) {
            return;
        }
        for (Object obj : list) {
            if (obj != null) {
                if (innerType instanceof Class<?> clazz) {
                    if (!clazz.isAssignableFrom(obj.getClass())) {
                        throw new IllegalArgumentException(String.format(
                                "Expects a list of %s but got a list of %s",
                                clazz.getSimpleName(), obj.getClass().getSimpleName()));
                    }
                } else if (List.class.isAssignableFrom(obj.getClass()) && innerType instanceof ParameterizedType) {
                    typeCheck((List<?>) obj, ((ParameterizedType) innerType).getActualTypeArguments()[0]);
                }
            }
        }
    }
}
