// ==++==
//
//   Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// ==--==
// =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
//
// OrderedHashRepartitionStream.cs
//
// <OWNER>Microsoft</OWNER>
//
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 
using System.Collections.Generic;
using System.Threading;
 
namespace System.Linq.Parallel
{
    internal class OrderedHashRepartitionStream<TInputOutput, THashKey, TOrderKey> : HashRepartitionStream<TInputOutput, THashKey, TOrderKey>
    {
        internal OrderedHashRepartitionStream(
            PartitionedStream<TInputOutput, TOrderKey> inputStream, Func<TInputOutput, THashKey> hashKeySelector,
            IEqualityComparer<THashKey> hashKeyComparer, IEqualityComparer<TInputOutput> elementComparer, CancellationToken cancellationToken)
            : base(inputStream.PartitionCount, inputStream.KeyComparer, hashKeyComparer, elementComparer)
        {
            m_partitions =
                new OrderedHashRepartitionEnumerator<TInputOutput, THashKey, TOrderKey>[inputStream.PartitionCount];
 
            // Initialize state shared among the partitions. A latch and a matrix of buffers. Note that
            // the actual elements in the buffer array are lazily allocated if needed.
            CountdownEvent barrier = new CountdownEvent(inputStream.PartitionCount);
            ListChunk<Pair<TInputOutput, THashKey>>[,] valueExchangeMatrix =
                new ListChunk<Pair<TInputOutput, THashKey>>[inputStream.PartitionCount, inputStream.PartitionCount];
            ListChunk<TOrderKey>[,] keyExchangeMatrix = new ListChunk<TOrderKey>[inputStream.PartitionCount, inputStream.PartitionCount];
 
            // Now construct each partition object.
            for (int i = 0; i < inputStream.PartitionCount; i++)
            {
                m_partitions[i] = new OrderedHashRepartitionEnumerator<TInputOutput, THashKey, TOrderKey>(
                    inputStream[i], inputStream.PartitionCount, i, hashKeySelector, this, barrier,
                    valueExchangeMatrix, keyExchangeMatrix, cancellationToken);
            }
        }
    }
}