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*/

using System.Collections.Generic;
using NGit;
using NGit.Transport;
using Sharpen;

namespace NGit.Transport
{
	/// <summary>
	/// <see cref="PreUploadHook">PreUploadHook</see>
	/// that delegates to a list of other hooks.
	/// <p>
	/// Hooks are run in the order passed to the constructor. If running a method on
	/// one hook throws an exception, execution of remaining hook methods is aborted.
	/// </summary>
	public class PreUploadHookChain : PreUploadHook
	{
		private readonly PreUploadHook[] hooks;

		private readonly int count;

		/// <summary>Create a new hook chaining the given hooks together.</summary>
		/// <remarks>Create a new hook chaining the given hooks together.</remarks>
		/// <param name="hooks">hooks to execute, in order.</param>
		/// <returns>a new hook chain of the given hooks.</returns>
		public static PreUploadHook NewChain<_T0>(IList<_T0> hooks) where _T0:PreUploadHook
		{
			PreUploadHook[] newHooks = new PreUploadHook[hooks.Count];
			int i = 0;
			foreach (PreUploadHook hook in hooks)
			{
				if (hook != PreUploadHook.NULL)
				{
					newHooks[i++] = hook;
				}
			}
			if (i == 0)
			{
				return PreUploadHook.NULL;
			}
			else
			{
				if (i == 1)
				{
					return newHooks[0];
				}
				else
				{
					return new NGit.Transport.PreUploadHookChain(newHooks, i);
				}
			}
		}

		/// <exception cref="NGit.Transport.ServiceMayNotContinueException"></exception>
		public override void OnBeginNegotiateRound<_T0>(UploadPack up, ICollection<_T0> wants
			, int cntOffered)
		{
			for (int i = 0; i < count; i++)
			{
				hooks[i].OnBeginNegotiateRound(up, wants, cntOffered);
			}
		}

		/// <exception cref="NGit.Transport.ServiceMayNotContinueException"></exception>
		public override void OnEndNegotiateRound<_T0>(UploadPack up, ICollection<_T0> wants
			, int cntCommon, int cntNotFound, bool ready)
		{
			for (int i = 0; i < count; i++)
			{
				hooks[i].OnEndNegotiateRound(up, wants, cntCommon, cntNotFound, ready);
			}
		}

		/// <exception cref="NGit.Transport.ServiceMayNotContinueException"></exception>
		public override void OnSendPack<_T0, _T1>(UploadPack up, ICollection<_T0> wants, 
			ICollection<_T1> haves)
		{
			for (int i = 0; i < count; i++)
			{
				hooks[i].OnSendPack(up, wants, haves);
			}
		}

		private PreUploadHookChain(PreUploadHook[] hooks, int count)
		{
			this.hooks = hooks;
			this.count = count;
		}
	}
}
