//-----------------------------------------------------------------------------
//Cortex
//Copyright (c) 2010-2015, Joshua Scoggins 
//All rights reserved.
//
//Redistribution and use in source and binary forms, with or without
//modification, are permitted provided that the following conditions are met:
//    * Redistributions of source code must retain the above copyright
//      notice, this list of conditions and the following disclaimer.
//    * Redistributions in binary form must reproduce the above copyright
//      notice, this list of conditions and the following disclaimer in the
//      documentation and/or other materials provided with the distribution.
//    * Neither the name of Cortex nor the
//      names of its contributors may be used to endorse or promote products
//      derived from this software without specific prior written permission.
//
//THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
//ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
//WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
//DISCLAIMED. IN NO EVENT SHALL Joshua Scoggins BE LIABLE FOR ANY
//DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
//(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
//LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
//ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
//(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
//SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//-----------------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.Runtime;
using System.Text;
using System.Text.RegularExpressions;
using System.Reflection;
using System.IO;
using System.Linq;

namespace Cortex.Operation
{
  public delegate void UnfulfilledHookResolver(Operation next);
  public abstract class Operation : List<Operation>
  {
    public int Index { get; set; }
    private Queue<UnfulfilledHookResolver> unfulfilledHooks;
    public Operation()
    {
      unfulfilledHooks = new Queue<UnfulfilledHookResolver>();
    }

    public abstract Operation Coalesce();
    ///<summary>
    ///Performs an initial fulfill by linking
    ///nodes together that can be linked together
    ///within the confines of the current operation
    ///Unfulfillable hooks need to be registered through
    ///the RegisterHook method so they can be linked to the
    ///next node within the parent operation of this operation
    ///</summary>
    public abstract void InitialFulfill();
    public void RegisterHook(UnfulfilledHookResolver resolver)
    {
      unfulfilledHooks.Enqueue(resolver);
    }
    ///<summary>
    ///Returns the head node of the current operation chain
    ///</summary>
    public abstract Operation First();
    public Operation OnTrueHook { get; set; }
    public Operation OnFalseHook { get; set; }
    public void ResolveHooks(Operation next)
    {
      if(unfulfilledHooks.Count > 0)
      {
        do
        {
          var hook = unfulfilledHooks.Dequeue();
          hook(next);
        }while(unfulfilledHooks.Count > 0);
      }
    }
    public abstract void Build(IGraphBuilder builder);
    public virtual void Enumerate(IGraphBuilder builder)
    {
      Index = builder.Index(this);
    }
  }
}
