using Lucene.Net.Index;
using Lucene.Net.Store;
using System;
using System.IO;

namespace Lucene.Net.Misc
{
    /*
	 * Licensed to the Apache Software Foundation (ASF) under one or more
	 * contributor license agreements.  See the NOTICE file distributed with
	 * this work for additional information regarding copyright ownership.
	 * The ASF 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.
	 */

    /// <summary>
    /// Utility to get document frequency and total number of occurrences (sum of the tf for each doc)  of a term. 
    /// </summary>
    public class GetTermInfo
    {
        public static void Main(string[] args)
        {

            FSDirectory dir = null;
            string inputStr = null;
            string field = null;

            if (args.Length == 3)
            {
                dir = FSDirectory.Open(new DirectoryInfo(args[0]));
                field = args[1];
                inputStr = args[2];
            }
            else
            {
                Usage();
                Environment.Exit(1);
            }

            TermInfo(dir, new Term(field, inputStr));
        }

        public static void TermInfo(Store.Directory dir, Term term)
        {
            IndexReader reader = DirectoryReader.Open(dir);
            Console.WriteLine("{0}:{1} \t totalTF = {2:#,##0} \t doc freq = {3:#,##0} \n", term.Field, term.Text(), reader.TotalTermFreq(term), reader.DocFreq(term));
        }

        private static void Usage()
        {
            // LUCENENET TODO: Usage info is dependant on packaging this into a standalone console application
            Console.WriteLine("\n\nusage:\n\t" + "java " + typeof(GetTermInfo).FullName + " <index dir> field term \n\n");
        }
    }
}