/*Copyright (c) 2011 Erik Garrison

  Permission is hereby granted, free of charge, to any person obtaining a copy of
  this software and associated documentation files (the "Software"), to deal in
  the Software without restriction, including without limitation the rights to
  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  of the Software, and to permit persons to whom the Software is furnished to do
  so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/

/* Modifed by Jeremiah Wala to switch unique_ptr to traditional
   pointer (requiring free on destruction) */

#ifndef SEQLIB_INTERVAL_TREE_H__
#define SEQLIB_INTERVAL_TREE_H__

#include <algorithm>
#include <iostream>
#include <vector>

namespace SeqLib
{

    template <class T, typename K = std::size_t>
    class TInterval
    {
    public:
        K start;
        K stop;
        T value;
        TInterval(K s, K e, const T& v) : start(s), stop(e), value(v)
        {
        }
    };

    template <class T, typename K>
    K intervalStart(const TInterval<T, K>& i)
    {
        return i.start;
    }

    template <class T, typename K>
    K intervalStop(const TInterval<T, K>& i)
    {
        return i.stop;
    }

    template <class T, typename K>
    std::ostream& operator<<(std::ostream& out, TInterval<T, K>& i)
    {
        out << "Interval(" << i.start << ", " << i.stop << "): " << i.value;
        return out;
    }

    template <class T, typename K = std::size_t>
    class IntervalStartSorter
    {
    public:
        bool operator()(const TInterval<T, K>& a, const TInterval<T, K>& b)
        {
            return a.start < b.start;
        }
    };

    template <class T, typename K = std::size_t>
    class TIntervalTree
    {

    public:
        typedef TInterval<T, K> interval;
        typedef std::vector<interval> intervalVector;
        typedef TIntervalTree<T, K> intervalTree;

        intervalVector intervals;
        intervalTree* left;
        intervalTree* right;
        K center;

        // jwala added destructor
        ~TIntervalTree<T, K>()
        {
            if (left)
                delete left;
            if (right)
                delete right;
        }

        TIntervalTree<T, K>(void) : left(NULL), right(NULL), center(0)
        {
        }

    private:
        intervalTree* copyTree(const intervalTree& orig)
        {
            return (new intervalTree(orig));
        }

    public:
        TIntervalTree<T, K>(const intervalTree& other)
            : intervals(other.intervals), left(other.left ? copyTree(*other.left) : NULL), right(other.right ? copyTree(*other.right) : NULL),
              center(other.center)
        {
        }

    public:
        TIntervalTree<T, K>& operator=(const intervalTree& other)
        {
            center = other.center;
            intervals = other.intervals;
            left = other.left ? copyTree(*other.left) : NULL;
            right = other.right ? copyTree(*other.right) : NULL;
            return *this;
        }

        // Note: changes the order of ivals
        TIntervalTree<T, K>(intervalVector& ivals, std::size_t depth = 16, std::size_t minbucket = 64, K leftextent = 0, K rightextent = 0,
                            std::size_t maxbucket = 512)
            : left(NULL), right(NULL)
        {

            --depth;
            IntervalStartSorter<T, K> intervalStartSorter;
            if (depth == 0 || (ivals.size() < minbucket && ivals.size() < maxbucket))
            {
                std::sort(ivals.begin(), ivals.end(), intervalStartSorter);
                intervals = ivals;
            }
            else
            {
                if (leftextent == 0 && rightextent == 0)
                {
                    // sort intervals by start
                    std::sort(ivals.begin(), ivals.end(), intervalStartSorter);
                }

                K leftp = 0;
                K rightp = 0;
                K centerp = 0;

                if (leftextent || rightextent)
                {
                    leftp = leftextent;
                    rightp = rightextent;
                }
                else
                {
                    leftp = ivals.front().start;
                    std::vector<K> stops;
                    stops.resize(ivals.size());
                    transform(ivals.begin(), ivals.end(), stops.begin(), intervalStop<T, K>);
                    rightp = *max_element(stops.begin(), stops.end());
                }

                // centerp = ( leftp + rightp ) / 2;
                centerp = ivals.at(ivals.size() / 2).start;
                center = centerp;

                intervalVector lefts;
                intervalVector rights;

                for (typename intervalVector::const_iterator i = ivals.begin(); i != ivals.end(); ++i)
                {
                    const interval& interval = *i;
                    if (interval.stop < center)
                    {
                        lefts.push_back(interval);
                    }
                    else if (interval.start > center)
                    {
                        rights.push_back(interval);
                    }
                    else
                    {
                        intervals.push_back(interval);
                    }
                }

                if (!lefts.empty())
                {
                    left = new intervalTree(lefts, depth, minbucket, leftp, centerp);
                }
                if (!rights.empty())
                {
                    right = new intervalTree(rights, depth, minbucket, centerp, rightp);
                }
            }
        }

        intervalVector findOverlapping(K start, K stop) const
        {
            intervalVector ov;
            this->findOverlapping(start, stop, ov);
            return ov;
        }

        void findOverlapping(K start, K stop, intervalVector& overlapping) const
        {
            if (!intervals.empty() && !(stop < intervals.front().start))
            {
                for (typename intervalVector::const_iterator i = intervals.begin(); i != intervals.end(); ++i)
                {
                    const interval& interval = *i;
                    if (interval.stop >= start && interval.start <= stop)
                    {
                        overlapping.push_back(interval);
                    }
                }
            }

            if (left && start <= center)
            {
                left->findOverlapping(start, stop, overlapping);
            }

            if (right && stop >= center)
            {
                right->findOverlapping(start, stop, overlapping);
            }
        }

        intervalVector findContained(K start, K stop) const
        {
            intervalVector contained;
            this->findContained(start, stop, contained);
            return contained;
        }

        void findContained(K start, K stop, intervalVector& contained) const
        {
            if (!intervals.empty() && !(stop < intervals.front().start))
            {
                for (typename intervalVector::const_iterator i = intervals.begin(); i != intervals.end(); ++i)
                {
                    const interval& interval = *i;
                    if (interval.start >= start && interval.stop <= stop)
                    {
                        contained.push_back(interval);
                    }
                }
            }

            if (left && start <= center)
            {
                left->findContained(start, stop, contained);
            }

            if (right && stop >= center)
            {
                right->findContained(start, stop, contained);
            }
        }

        //~TIntervalTree(void) = default;
    };

} // namespace SeqLib
#endif
