etl/src/flat_map.h

///\file

/******************************************************************************
The MIT License(MIT)

Embedded Template Library.
https://github.com/ETLCPP/etl
http://www.etlcpp.com

Copyright(c) 2015 jwellbelove

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files(the "Software"), to deal
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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.
******************************************************************************/

#ifndef __ETL_FLAT_MAP__
#define __ETL_FLAT_MAP__

#include "platform.h"
#include "reference_flat_map.h"
#include "pool.h"

#undef ETL_FILE
#define ETL_FILE "2"

//*****************************************************************************
///\defgroup flat_map flat_map
/// A flat_map with the capacity defined at compile time.
/// Has insertion of O(N) and flat_map of O(logN)
/// Duplicate entries are not allowed.
///\ingroup containers
//*****************************************************************************

namespace etl
{
  //***************************************************************************
  /// The base class for specifically sized flat_maps.
  /// Can be used as a reference type for all flat_maps containing a specific type.
  ///\ingroup flat_map
  //***************************************************************************
  template <typename TKey, typename TMapped, typename TKeyCompare = std::less<TKey> >
  class iflat_map : private etl::ireference_flat_map<TKey, TMapped, TKeyCompare>
  {
  private:

    typedef etl::ireference_flat_map<TKey, TMapped, TKeyCompare> refmap_t;
    typedef typename refmap_t::lookup_t lookup_t;
    typedef etl::ipool storage_t;

  public:


    typedef std::pair<const TKey, TMapped> value_type;
    typedef TKey              key_type;
    typedef TMapped           mapped_type;
    typedef TKeyCompare       key_compare;
    typedef value_type&       reference;
    typedef const value_type& const_reference;
    typedef value_type*       pointer;
    typedef const value_type* const_pointer;
    typedef size_t            size_type;

    typedef typename refmap_t::iterator       iterator;
    typedef typename refmap_t::const_iterator const_iterator;

    typedef std::reverse_iterator<iterator>       reverse_iterator;
    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
    typedef typename std::iterator_traits<iterator>::difference_type difference_type;

  protected:

    typedef typename etl::parameter_type<TKey>::type key_parameter_t;

  private:

    //*********************************************************************
    /// How to compare elements and keys.
    //*********************************************************************
    class compare
    {
    public:

      bool operator ()(const value_type& element, key_type key) const
      {
        return key_compare()(element.first, key);
      }

      bool operator ()(key_type key, const value_type& element) const
      {
        return key_compare()(key, element.first);
      }
    };

  public:

    //*********************************************************************
    /// Returns an iterator to the beginning of the flat_map.
    ///\return An iterator to the beginning of the flat_map.
    //*********************************************************************
    iterator begin()
    {
      return refmap_t::begin();
    }

    //*********************************************************************
    /// Returns a const_iterator to the beginning of the flat_map.
    ///\return A const iterator to the beginning of the flat_map.
    //*********************************************************************
    const_iterator begin() const
    {
      return refmap_t::begin();
    }

    //*********************************************************************
    /// Returns an iterator to the end of the flat_map.
    ///\return An iterator to the end of the flat_map.
    //*********************************************************************
    iterator end()
    {
      return refmap_t::end();
    }

    //*********************************************************************
    /// Returns a const_iterator to the end of the flat_map.
    ///\return A const iterator to the end of the flat_map.
    //*********************************************************************
    const_iterator end() const
    {
      return refmap_t::end();
    }

    //*********************************************************************
    /// Returns a const_iterator to the beginning of the flat_map.
    ///\return A const iterator to the beginning of the flat_map.
    //*********************************************************************
    const_iterator cbegin() const
    {
      return refmap_t::cbegin();
    }

    //*********************************************************************
    /// Returns a const_iterator to the end of the flat_map.
    ///\return A const iterator to the end of the flat_map.
    //*********************************************************************
    const_iterator cend() const
    {
      return refmap_t::cend();
    }

    //*********************************************************************
    /// Returns an reverse iterator to the reverse beginning of the flat_map.
    ///\return Iterator to the reverse beginning of the flat_map.
    //*********************************************************************
    reverse_iterator rbegin()
    {
      return refmap_t::rbegin();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the reverse beginning of the flat_map.
    ///\return Const iterator to the reverse beginning of the flat_map.
    //*********************************************************************
    const_reverse_iterator rbegin() const
    {
      return refmap_t::rbegin();
    }

    //*********************************************************************
    /// Returns a reverse iterator to the end + 1 of the flat_map.
    ///\return Reverse iterator to the end + 1 of the flat_map.
    //*********************************************************************
    reverse_iterator rend()
    {
      return refmap_t::rend();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the end + 1 of the flat_map.
    ///\return Const reverse iterator to the end + 1 of the flat_map.
    //*********************************************************************
    const_reverse_iterator rend() const
    {
      return refmap_t::rend();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the reverse beginning of the flat_map.
    ///\return Const reverse iterator to the reverse beginning of the flat_map.
    //*********************************************************************
    const_reverse_iterator crbegin() const
    {
      return refmap_t::crbegin();
    }

    //*********************************************************************
    /// Returns a const reverse iterator to the end + 1 of the flat_map.
    ///\return Const reverse iterator to the end + 1 of the flat_map.
    //*********************************************************************
    const_reverse_iterator crend() const
    {
      return refmap_t::crend();
    }

    //*********************************************************************
    /// Returns a reference to the value at index 'key'
    ///\param i The index.
    ///\return A reference to the value at index 'key'
    //*********************************************************************
    mapped_type& operator [](key_parameter_t key)
    {
      iterator i_element = lower_bound(key);

      // Doesn't already exist?
      if (i_element == end())
      {
        value_type* pvalue = storage.allocate<value_type>();
        ::new (pvalue) value_type();
        ++construct_count;

        std::pair<iterator, bool> result = refmap_t::insert_at(i_element, *pvalue);
        i_element->second = result.first->second;
      }

      return i_element->second;
    }

    //*********************************************************************
    /// Returns a reference to the value at index 'key'
    /// If asserts or exceptions are enabled, emits an etl::flat_map_out_of_bounds if the key is not in the range.
    ///\param i The index.
    ///\return A reference to the value at index 'key'
    //*********************************************************************
    mapped_type& at(key_parameter_t key)
    {
      return refmap_t::at(key);
    }

    //*********************************************************************
    /// Returns a const reference to the value at index 'key'
    /// If asserts or exceptions are enabled, emits an etl::flat_map_out_of_bounds if the key is not in the range.
    ///\param i The index.
    ///\return A const reference to the value at index 'key'
    //*********************************************************************
    const mapped_type& at(key_parameter_t key) const
    {
      return refmap_t::at(key);
    }

    //*********************************************************************
    /// Assigns values to the flat_map.
    /// If ETL_THROW_EXCEPTIONS & ETL_DEBUG are defined, emits flat_map_full if the flat_map does not have enough free space.
    /// If ETL_THROW_EXCEPTIONS & ETL_DEBUG are defined, emits flat_map_iterator if the iterators are reversed.
    ///\param first The iterator to the first element.
    ///\param last  The iterator to the last element + 1.
    //*********************************************************************
    template <typename TIterator>
    void assign(TIterator first, TIterator last)
    {
#if defined(ETL_DEBUG)
      difference_type d = std::distance(first, last);
      ETL_ASSERT(d <= difference_type(capacity()), ETL_ERROR(flat_map_full));
#endif

      clear();

      while (first != last)
      {
        insert(*first++);
      }
    }

    //*********************************************************************
    /// Inserts a value to the flat_map.
    /// If asserts or exceptions are enabled, emits flat_map_full if the flat_map is already full.
    ///\param value    The value to insert.
    //*********************************************************************
    std::pair<iterator, bool> insert(const_reference value)
    {
      iterator i_element = lower_bound(value.first);

      std::pair<iterator, bool> result(i_element, false);

      // Doesn't already exist?
      if ((i_element == end() || (i_element->first != value.first)))
      {
        ETL_ASSERT(!refmap_t::full(), ETL_ERROR(flat_map_full));

        value_type* pvalue = storage.allocate<value_type>();
        ::new (pvalue) value_type(value);
        ++construct_count;
        result = refmap_t::insert_at(i_element, *pvalue);
      }

      return result;
    }

    //*********************************************************************
    /// Inserts a value to the flat_map.
    /// If asserts or exceptions are enabled, emits flat_map_full if the flat_map is already full.
    ///\param position The position to insert at.
    ///\param value    The value to insert.
    //*********************************************************************
    iterator insert(iterator position, const_reference value)
    {
      return insert(value).first;
    }

    //*********************************************************************
    /// Inserts a range of values to the flat_map.
    /// If asserts or exceptions are enabled, emits flat_map_full if the flat_map does not have enough free space.
    ///\param position The position to insert at.
    ///\param first    The first element to add.
    ///\param last     The last + 1 element to add.
    //*********************************************************************
    template <class TIterator>
    void insert(TIterator first, TIterator last)
    {
      while (first != last)
      {
        insert(*first++);
      }
    }

    //*********************************************************************
    /// Erases an element.
    ///\param key The key to erase.
    ///\return The number of elements erased. 0 or 1.
    //*********************************************************************
    size_t erase(key_parameter_t key)
    {
      iterator i_element = find(key);

      if (i_element == end())
      {
        return 0;
      }
      else
      {
        i_element->~value_type();
        storage.release(etl::addressof(*i_element));
        refmap_t::erase(i_element);
        --construct_count;
        return 1;
      }
    }

    //*********************************************************************
    /// Erases an element.
    ///\param i_element Iterator to the element.
    //*********************************************************************
    void erase(iterator i_element)
    {
      i_element->~value_type();
      storage.release(etl::addressof(*i_element));
      refmap_t::erase(i_element);
      --construct_count;
    }

    //*********************************************************************
    /// Erases a range of elements.
    /// The range includes all the elements between first and last, including the
    /// element pointed by first, but not the one pointed by last.
    ///\param first Iterator to the first element.
    ///\param last  Iterator to the last element.
    //*********************************************************************
    void erase(iterator first, iterator last)
    {
      iterator itr = first;

      while (itr != last)
      {
        itr->~value_type();
        storage.release(etl::addressof(*itr));
        ++itr;
        --construct_count;
      }

      refmap_t::erase(first, last);
    }

    //*************************************************************************
    /// Clears the flat_map.
    //*************************************************************************
    void clear()
    {
      if ETL_IF_CONSTEXPR(etl::is_trivially_destructible<value_type>::value)
      {
        storage.release_all();
      }
      else
      {
        iterator itr = begin();

        while (itr != end())
        {
          itr->~value_type();
          storage.release(etl::addressof(*itr));
          ++itr;
        }
      }

      construct_count.clear();
      refmap_t::clear();
    }

    //*********************************************************************
    /// Finds an element.
    ///\param key The key to search for.
    ///\return An iterator pointing to the element or end() if not found.
    //*********************************************************************
    iterator find(key_parameter_t key)
    {
      return refmap_t::find(key);
    }

    //*********************************************************************
    /// Finds an element.
    ///\param key The key to search for.
    ///\return An iterator pointing to the element or end() if not found.
    //*********************************************************************
    const_iterator find(key_parameter_t key) const
    {
      return refmap_t::find(key);
    }

    //*********************************************************************
    /// Counts an element.
    ///\param key The key to search for.
    ///\return 1 if the key exists, otherwise 0.
    //*********************************************************************
    size_t count(key_parameter_t key) const
    {
      return refmap_t::count(key);
    }

    //*********************************************************************
    /// Finds the lower bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    iterator lower_bound(key_parameter_t key)
    {
      return refmap_t::lower_bound(key);
    }

    //*********************************************************************
    /// Finds the lower bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    const_iterator lower_bound(key_parameter_t key) const
    {
      return refmap_t::lower_bound(key);
    }

    //*********************************************************************
    /// Finds the upper bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    iterator upper_bound(key_parameter_t key)
    {
      return refmap_t::upper_bound(key);
    }

    //*********************************************************************
    /// Finds the upper bound of a key
    ///\param key The key to search for.
    ///\return An iterator.
    //*********************************************************************
    const_iterator upper_bound(key_parameter_t key) const
    {
      return refmap_t::upper_bound(key);
    }

    //*********************************************************************
    /// Finds the range of equal elements of a key
    ///\param key The key to search for.
    ///\return An iterator pair.
    //*********************************************************************
    std::pair<iterator, iterator> equal_range(key_parameter_t key)
    {
      return refmap_t::equal_range(key);
    }

    //*********************************************************************
    /// Finds the range of equal elements of a key
    ///\param key The key to search for.
    ///\return An iterator pair.
    //*********************************************************************
    std::pair<const_iterator, const_iterator> equal_range(key_parameter_t key) const
    {
      return refmap_t::equal_range(key);
    }

    //*************************************************************************
    /// Assignment operator.
    //*************************************************************************
    iflat_map& operator = (const iflat_map& rhs)
    {
      if (&rhs != this)
      {
        assign(rhs.cbegin(), rhs.cend());
      }

      return *this;
    }

    //*************************************************************************
    /// Gets the current size of the flat_map.
    ///\return The current size of the flat_map.
    //*************************************************************************
    size_type size() const
    {
      return refmap_t::size();
    }

    //*************************************************************************
    /// Checks the 'empty' state of the flat_map.
    ///\return <b>true</b> if empty.
    //*************************************************************************
    bool empty() const
    {
      return refmap_t::empty();
    }

    //*************************************************************************
    /// Checks the 'full' state of the flat_map.
    ///\return <b>true</b> if full.
    //*************************************************************************
    bool full() const
    {
      return refmap_t::full();
    }

    //*************************************************************************
    /// Returns the capacity of the flat_map.
    ///\return The capacity of the flat_map.
    //*************************************************************************
    size_type capacity() const
    {
      return refmap_t::capacity();
    }

    //*************************************************************************
    /// Returns the maximum possible size of the flat_map.
    ///\return The maximum size of the flat_map.
    //*************************************************************************
    size_type max_size() const
    {
      return refmap_t::max_size();
    }

    //*************************************************************************
    /// Returns the remaining capacity.
    ///\return The remaining capacity.
    //*************************************************************************
    size_t available() const
    {
      return refmap_t::available();
    }

  protected:

    //*********************************************************************
    /// Constructor.
    //*********************************************************************
    iflat_map(lookup_t& lookup_, storage_t& storage_)
      : refmap_t(lookup_),
        storage(storage_)
    {
    }

  private:

    // Disable copy construction.
    iflat_map(const iflat_map&);

    storage_t& storage;

    /// Internal debugging.
    etl::debug_count construct_count;
  };

  //***************************************************************************
  /// Equal operator.
  ///\param lhs Reference to the first flat_map.
  ///\param rhs Reference to the second flat_map.
  ///\return <b>true</b> if the arrays are equal, otherwise <b>false</b>
  ///\ingroup flat_map
  //***************************************************************************
  template <typename TKey, typename TMapped, typename TKeyCompare>
  bool operator ==(const etl::iflat_map<TKey, TMapped, TKeyCompare>& lhs, const etl::iflat_map<TKey, TMapped, TKeyCompare>& rhs)
  {
    return (lhs.size() == rhs.size()) && std::equal(lhs.begin(), lhs.end(), rhs.begin());
  }

  //***************************************************************************
  /// Not equal operator.
  ///\param lhs Reference to the first flat_map.
  ///\param rhs Reference to the second flat_map.
  ///\return <b>true</b> if the arrays are not equal, otherwise <b>false</b>
  ///\ingroup flat_map
  //***************************************************************************
  template <typename TKey, typename TMapped, typename TKeyCompare>
  bool operator !=(const etl::iflat_map<TKey, TMapped, TKeyCompare>& lhs, const etl::iflat_map<TKey, TMapped, TKeyCompare>& rhs)
  {
    return !(lhs == rhs);
  }

  //***************************************************************************
  /// A flat_map implementation that uses a fixed size buffer.
  ///\tparam TKey     The key type.
  ///\tparam TValue   The value type.
  ///\tparam TCompare The type to compare keys. Default = std::less<TKey>
  ///\tparam MAX_SIZE_ The maximum number of elements that can be stored.
  ///\ingroup flat_map
  //***************************************************************************
  template <typename TKey, typename TValue, const size_t MAX_SIZE_, typename TCompare = std::less<TKey> >
  class flat_map : public etl::iflat_map<TKey, TValue, TCompare>
  {
  public:

    static const size_t MAX_SIZE = MAX_SIZE_;

    //*************************************************************************
    /// Constructor.
    //*************************************************************************
    flat_map()
      : etl::iflat_map<TKey, TValue, TCompare>(lookup, storage)
    {
    }

    //*************************************************************************
    /// Copy constructor.
    //*************************************************************************
    flat_map(const flat_map& other)
      : etl::iflat_map<TKey, TValue, TCompare>(lookup, storage)
    {
      etl::iflat_map<TKey, TValue, TCompare>::assign(other.cbegin(), other.cend());
    }

    //*************************************************************************
    /// Constructor, from an iterator range.
    ///\tparam TIterator The iterator type.
    ///\param first The iterator to the first element.
    ///\param last  The iterator to the last element + 1.
    //*************************************************************************
    template <typename TIterator>
    flat_map(TIterator first, TIterator last)
      : etl::iflat_map<TKey, TValue, TCompare>(lookup, storage)
    {
      etl::iflat_map<TKey, TValue, TCompare>::assign(first, last);
    }

    //*************************************************************************
    /// Destructor.
    //*************************************************************************
    ~flat_map()
    {
      etl::iflat_map<TKey, TValue, TCompare>::clear();
    }

    //*************************************************************************
    /// Assignment operator.
    //*************************************************************************
    flat_map& operator = (const flat_map& rhs)
    {
      if (&rhs != this)
      {
        etl::iflat_map<TKey, TValue, TCompare>::assign(rhs.cbegin(), rhs.cend());
      }

      return *this;
    }

  private:

    typedef typename etl::iflat_map<TKey, TValue, TCompare>::value_type node_t;

    /// The pool of nodes.
    etl::pool<node_t, MAX_SIZE> storage;

    /// The vector that stores pointers to the nodes.
    etl::vector<node_t*, MAX_SIZE> lookup;
  };
}

#undef ETL_FILE

#endif