/*
* Licensed to CRATE Technology GmbH ("Crate") under one or more contributor
* license agreements.  See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.  Crate 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.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial agreement.
*/

package io.crate.sql.tree;

import com.google.common.base.MoreObjects;
import com.google.common.base.Preconditions;

import java.util.List;

public class AliasedRelation
    extends Relation {
    private final Relation relation;
    private final String alias;
    private final List<String> columnNames;

    public AliasedRelation(Relation relation, String alias, List<String> columnNames) {
        Preconditions.checkNotNull(relation, "relation is null");
        Preconditions.checkNotNull(alias, " is null");

        this.relation = relation;
        this.alias = alias;
        this.columnNames = columnNames;
    }

    public Relation getRelation() {
        return relation;
    }

    public String getAlias() {
        return alias;
    }

    public List<String> getColumnNames() {
        return columnNames;
    }

    @Override
    public <R, C> R accept(AstVisitor<R, C> visitor, C context) {
        return visitor.visitAliasedRelation(this, context);
    }

    @Override
    public String toString() {
        return MoreObjects.toStringHelper(this)
            .add("relation", relation)
            .add("alias", alias)
            .add("columnNames", columnNames)
            .omitNullValues()
            .toString();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }

        AliasedRelation that = (AliasedRelation) o;

        if (!alias.equals(that.alias)) {
            return false;
        }
        if (columnNames != null ? !columnNames.equals(that.columnNames) : that.columnNames != null) {
            return false;
        }
        if (!relation.equals(that.relation)) {
            return false;
        }

        return true;
    }

    @Override
    public int hashCode() {
        int result = relation.hashCode();
        result = 31 * result + alias.hashCode();
        result = 31 * result + (columnNames != null ? columnNames.hashCode() : 0);
        return result;
    }

}