/*
 * 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.collect.HashMultimap;
import com.google.common.collect.Multimap;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public abstract class Literal
    extends Expression {

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

    public static Literal fromObject(Object value) {
        Literal literal = null;
        if (value == null) {
            literal = NullLiteral.INSTANCE;
        } else if (value instanceof String) {
            literal = new StringLiteral((String) value);
        } else if (value instanceof Number) {
            if (value instanceof Float || value instanceof Double) {
                literal = new DoubleLiteral(value.toString());
            } else if (value instanceof Short || value instanceof Integer || value instanceof Long) {
                literal = new LongLiteral(value.toString());
            }
        } else if (value instanceof Boolean) {
            literal = (Boolean) value ? BooleanLiteral.TRUE_LITERAL : BooleanLiteral.FALSE_LITERAL;
        } else if (value instanceof Object[]) {
            List<Expression> expressions = new ArrayList<>();
            for (Object o : (Object[]) value) {
                expressions.add(fromObject(o));
            }
            literal = new ArrayLiteral(expressions);
        } else if (value instanceof Map) {
            Multimap<String, Expression> map = HashMultimap.create();
            @SuppressWarnings("unchecked") Map<String, Object> valueMap = (Map<String, Object>) value;
            for (Map.Entry<String, Object> entry : valueMap.entrySet()) {
                map.put(entry.getKey(), fromObject(entry.getValue()));
            }
            literal = new ObjectLiteral(map);
        }
        return literal;
    }
}