/*
 * Copyright 2019-2023 The Polypheny Project
 *
 * 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 org.polypheny.db.sql.language;


import org.polypheny.db.algebra.type.AlgDataType;
import org.polypheny.db.algebra.type.AlgDataTypeFactory;
import org.polypheny.db.languages.ParserPos;
import org.polypheny.db.type.PolyType;
import org.polypheny.db.util.TimestampString;


/**
 * A SQL literal representing a DATE, TIME or TIMESTAMP value.
 *
 * Examples:
 *
 * <ul>
 * <li>DATE '2004-10-22'</li>
 * <li>TIME '14:33:44.567'</li>
 * <li><code>TIMESTAMP '1969-07-21 03:15 GMT'</code></li>
 * </ul>
 */
public abstract class SqlAbstractDateTimeLiteral extends SqlLiteral {

    protected final boolean hasTimeZone;
    protected final int precision;


    /**
     * Constructs a datetime literal.
     */
    protected SqlAbstractDateTimeLiteral( Object d, boolean tz, PolyType typeName, int precision, ParserPos pos ) {
        super( d, typeName, pos );
        this.hasTimeZone = tz;
        this.precision = precision;
    }


    /**
     * Converts this literal to a {@link TimestampString}.
     */
    protected TimestampString getTimestamp() {
        return (TimestampString) value;
    }


    public int getPrec() {
        return precision;
    }


    /**
     * Returns e.g. <code>DATE '1969-07-21'</code>.
     */
    public abstract String toString();

    /**
     * Returns e.g. <code>1969-07-21</code>.
     */
    public abstract String toFormattedString();


    @Override
    public AlgDataType createSqlType( AlgDataTypeFactory typeFactory ) {
        return typeFactory.createPolyType( getTypeName(), getPrec() );
    }


    @Override
    public void unparse( SqlWriter writer, int leftPrec, int rightPrec ) {
        writer.literal( this.toString() );
    }

}


