#if FEATURE_COLLATION
using Icu.Collation;
using Lucene.Net.Analysis.TokenAttributes;
using System;

namespace Lucene.Net.Collation.TokenAttributes
{
    /*
     * 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>
    /// Extension of <see cref="CharTermAttribute"/> that encodes the term
    /// text as a binary Unicode collation key instead of as UTF-8 bytes.
    /// </summary>
    // LUCENENET TODO: A better option would be to contribute to the icu.net library and
    // make it CLS compliant (at least the parts of it we use)
    [CLSCompliant(false)]
    public class CollatedTermAttributeImpl : CharTermAttribute
	{
		private readonly Collator collator;

		/// <summary>
		/// Create a new <see cref="CollatedTermAttributeImpl"/> </summary>
		/// <param name="collator"> Collation key generator </param>
		public CollatedTermAttributeImpl(Collator collator)
		{
            // clone in case JRE doesn't properly sync,
            // or to reduce contention in case they do
            this.collator = (Collator)collator.Clone();
		}

		public override void FillBytesRef()
		{
			var bytes = this.BytesRef;

			//LUCENENET TODO: Verify that this is correct. Java's byte[] is signed and Big Endian, .NET's is unsigned and Little Endian.
			bytes.Bytes = this.collator.GetSortKey(this.ToString()).KeyData;
			bytes.Offset = 0;
			bytes.Length = bytes.Bytes.Length;
		}
	}
}
#endif