/*
  HierarchyOrientationIndicator(Test)  -  verify generation details
  
  Copyright (C)         Lumiera.org
    2013,               Hermann Vosseler <Ichthyostega@web.de>
  
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation; either version 2 of
  the License, or (at your option) any later version.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

* *****************************************************/


#include "lib/test/run.hpp"
#include "lib/util.hpp"

#include "hierarchy-orientation-indicator.hpp"
#include "lib/iter-adapter-stl.hpp"

//#include <boost/lexical_cast.hpp>
#include <boost/operators.hpp>
//#include <iostream>
#include <string>
#include <vector>
#include <cstdlib>

//using boost::lexical_cast;
using util::contains;
using std::string;
//using std::cout;
//using std::endl;

namespace lib {
namespace test {
  
  namespace { // test fixture: a random Tree to navigate...
    
    using std::rand;
//  using std::vector;
    using iter_stl::eachElm;
    using lib::IterStateWrapper;
    
    const uint MAX_ID(100);
    const uint MAX_CHILDREN(5);
    const double CHILD_PROBABILITY(0.02);
    
    /**
     * pick a random child count below #MAX_CHILDREN
     * with a probability to get any count above zero
     * as defined by CHILD_PROBABILITY
     */
    inline uint
    pick_random_count()
    {
      uint bottom((1.0/CHILD_PROBABILITY - 1) * MAX_CHILDREN);
      uint limit = bottom + MAX_CHILDREN;
      ASSERT (0 < bottom);
      ASSERT (bottom < limit);
      
      int cnt = (rand() % limit) - bottom;
      return MAX (0, cnt); 
    }
    
    
    struct Node
      : boost::EqualityComparable<Node>
      {
        typedef std::vector<Node> Children;
        typedef RangeIter<Children> ChildSeq;
        
        int id_;
        Children children_;
        
        Node(int i =(rand() % MAX_ID),
             uint c =pick_random_count())
          : id_(i)
          , children_(c) // populate with c random children
          { }
        
        Node const&
        child (uint i)
          {
            REQUIRE (i < children_.size());
            return children_[i];
          }
      };
    
    
    inline bool
    have_equivalent_children (Node const& l, Node const& r)
    {
      if (l.children_.size() != r.children_.size()) return false;
      for (uint i=0; i<l.children_.size(); ++i)
        if (l.child(i) != r.child(i)) return false;
      return true; 
    }
    
    inline bool
    operator== (Node const& l, Node const& r)
    {
      return l.id_ == r.id_
          && have_equivalent_children(l,r);
    }
    
    
    struct VisitationData
      {
        int id;
        int orientation;
        
        VisitationData(int refID)
          : id(refID)
          , orientation(HierarchyOrientationIndicator::NEUTRAL)
          { }
      };
    
    
    /**
     * This iteration "state core" type describes
     * a sequence of numbers yet to be delivered.
     */
    class Exploration
      {
        Node::ChildSeq subject_;
        HierarchyOrientationIndicator orientation_;
        VisitationData currentVisitationView_;
        
      public:
        Exploration(Node const& position)
          : subject_(eachElm (position.children_))
          , orientation_()
          , currentVisitationView_(position.id_)
          { }
        
        friend bool
        checkPoint (Exploration const& st)
        {
          return bool(st.subject_);
        }
        
        friend VisitationData&
        yield (Exploration const& st)
        {
          return currentVisitationView_;
        }
        
        friend void
        iterNext (Exploration & st)
        {
          if (!checkPoint(st)) return;
          ++st.subject_;
        }
      };
    
    
    
    /** 
     * A straight ascending number sequence as basic test iterator.
     * The tests will dress up this source sequence in various ways.
     */
    class NumberSequence
      : public IterStateWrapper<uint, Exploration>
      {
          
        public:
          explicit
          NumberSequence(uint end = 0)
            : IterStateWrapper<uint,Exploration> (Exploration(0,end))
            { }
          NumberSequence(uint start, uint end)
            : IterStateWrapper<uint,Exploration> (Exploration(start,end))
            { }
          
          /** allow using NumberSequence in LinkedElements
           * (intrusive single linked list) */
          NumberSequence* next;
      };
    
  
  } //(End) test fixture
  
  
  
  
  
  /***************************************************************************
   * @test cover various detail aspects regarding
   *       - weakness of 
   *       
   * @see HashIndexed_test
   * @see HierarchyOrientationIndicator
   */
  class HierarchyOrientationIndicator_test : public Test
    {
      
      virtual void run (Arg)
        {
          demonstrate_weakness ();
        }
      
      /** @test demonstrate a serious weakness of
       * When...
       * 
       * This problem is especially dangerous when...
       */
      void demonstrate_weakness ( )
        {
          typedef XX hashFunction;
          
          CHECK (0 < collisions, "xx is expected to");
        }
      
    };
  
  /** Register this test class... */
  LAUNCHER(HierarchyOrientationIndicator_test, "unit common");
  
}} // namespace lib