/*
 * 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.
 */

using System;

using OpenBitSet = Lucene.Net.Util.OpenBitSet;
using IndexReader = Lucene.Net.Index.IndexReader;

namespace Lucene.Net.Search
{
	
	/// <summary> Constrains search results to only match those which also match a provided
	/// query.  
	/// 
	/// <p> This could be used, for example, with a {@link RangeQuery} on a suitably
	/// formatted date field to implement date filtering.  One could re-use a single
	/// QueryFilter that matches, e.g., only documents modified within the last
	/// week.  The QueryFilter and RangeQuery would only need to be reconstructed
	/// once per day.
	/// 
	/// </summary>
	/// <version>  $Id:$
	/// </version>
	[Serializable]
	public class QueryWrapperFilter : Filter
	{
		private class AnonymousClassHitCollector:HitCollector
		{
			public AnonymousClassHitCollector(System.Collections.BitArray bits, QueryWrapperFilter enclosingInstance)
			{
				InitBlock(bits, enclosingInstance);
			}
			private void  InitBlock(System.Collections.BitArray bits, QueryWrapperFilter enclosingInstance)
			{
				this.bits = bits;
				this.enclosingInstance = enclosingInstance;
			}
			private System.Collections.BitArray bits;
			private QueryWrapperFilter enclosingInstance;
			public QueryWrapperFilter Enclosing_Instance
			{
				get
				{
					return enclosingInstance;
				}
				
			}
			public override void  Collect(int doc, float score)
			{
				bits.Set(doc, true);
			}
		}

        private class AnonymousClassHitCollector2 : HitCollector
        {
            public AnonymousClassHitCollector2(OpenBitSet bits, QueryWrapperFilter enclosingInstance)
            {
                InitBlock(bits, enclosingInstance);
            }
            private void InitBlock(OpenBitSet bits, QueryWrapperFilter enclosingInstance)
            {
                this.bits = bits;
                this.enclosingInstance = enclosingInstance;
            }
            private OpenBitSet bits;
            private QueryWrapperFilter enclosingInstance;
            public QueryWrapperFilter Enclosing_Instance
            {
                get
                {
                    return enclosingInstance;
                }

            }
            public override void Collect(int doc, float score)
            {
                bits.Set(doc);
            }
        }

        private Query query;
		
		/// <summary>Constructs a filter which only matches documents matching
		/// <code>query</code>.
		/// </summary>
		public QueryWrapperFilter(Query query)
		{
			this.query = query;
		}
		
        [System.Obsolete("Use getDocIdSet(IndexReader) instead.")]
		public override System.Collections.BitArray Bits(IndexReader reader)
		{
			System.Collections.BitArray bits = new System.Collections.BitArray((reader.MaxDoc() % 64 == 0 ? reader.MaxDoc() / 64 : reader.MaxDoc() / 64 + 1) * 64);
			new IndexSearcher(reader).Search(query, new AnonymousClassHitCollector(bits, this));
			return bits;
		}

        public override DocIdSet GetDocIdSet(IndexReader reader)
        {
            OpenBitSet bits = new OpenBitSet((reader.MaxDoc() % 64 == 0 ? reader.MaxDoc() / 64 : reader.MaxDoc() / 64 + 1) * 64);
            new IndexSearcher(reader).Search(query, new AnonymousClassHitCollector2(bits, this));
            return bits;
        }

        public override System.String ToString()
		{
			return "QueryWrapperFilter(" + query + ")";
		}
		
		public  override bool Equals(object o)
		{
			if (!(o is QueryWrapperFilter))
				return false;
			return this.query.Equals(((QueryWrapperFilter) o).query);
		}
		
		public override int GetHashCode()
		{
			return query.GetHashCode() ^ unchecked((int) 0x923F64B9);
		}
	}
}