/*
 * Copyright 2013 Future Systems
 * 
 * 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.araqne.logdb.query.parser;

import java.util.Arrays;
import java.util.Map;

import org.araqne.logdb.AbstractQueryCommandParser;
import org.araqne.logdb.QueryCommand;
import org.araqne.logdb.QueryContext;
import org.araqne.logdb.query.command.Search;
import org.araqne.logdb.query.expr.Expression;

public class SearchParser extends AbstractQueryCommandParser {

	public SearchParser() {
		setDescriptions(
				"Filter tuples using expression. Tuples are fed into next command only if evaluated expression is true. Query will be completed after output count is over limit.",
				"조건 표현식에 따라 레코드를 필터링합니다. 표현식이 참인 경우에만 레코드가 다음 쿼리 명령어로 전달됩니다. limit 옵션이 주어지는 경우, 주어진 갯수만큼 표현식이 참이 되면 쿼리 전체가 완료됩니다.");
		setOptions("limit", false, "Max output count", "최대 출력 건수");
	}

	@Override
	public String getCommandName() {
		return "search";
	}

	@Override
	public QueryCommand parse(QueryContext context, String commandString) {
		ParseResult r = QueryTokenizer.parseOptions(context, commandString, getCommandName().length(), Arrays.asList("limit"),
				getFunctionRegistry());

		@SuppressWarnings("unchecked")
		Map<String, String> options = (Map<String, String>) r.value;
		String exprToken = commandString.substring(r.next);
		Long limit = null;
		if (options.containsKey("limit"))
			limit = Long.parseLong(options.get("limit"));

		Expression expr = null;
		if (!exprToken.trim().isEmpty())
			expr = ExpressionParser.parse(context, exprToken, getFunctionRegistry());
		return new Search(limit, expr);
	}
}