/*
 * Mask.hpp
 *
 *  Created on: Sep 7, 2012
 *      Author: heber
 */

#ifndef MASK_HPP_
#define MASK_HPP_


// include config.h
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <set>

#include "CodePatterns/Assert.hpp"

#include "types.hpp"

/** A Mask_t is just a set of ids such that one can use the set as a filter
 * for any type by looking them up in the map.
 *
 * The interface is such that we have a bitmask for every given id. Only we
 * store only ids associated to true.
 */
template <typename T>
struct Mask_t : public std::set<T>
{
  /** Checks whether the bit for the given \a id is true.
   *
   * @param id id to check
   * @return true - bit set, false - bit not set
   */
  bool isTrue(const T id) const {
    const typename std::set<T>::const_iterator iter = std::set<T>::find(id);
    return (iter != std::set<T>::end());
  }

  /** Checks whether the bit for the given \a id is true.
   *
   * @param id id to check
   * @return true - bit set, false - bit not set
   */
  bool isFalse(const T id) const {
    return (!isTrue(id));
  }

  /** Setter for the bit associated to \a id.
   *
   * @param id id to set to true
   */
  void setTrue(const T id)
  {
    insert(id);
  }

  /** Unsetter for the bit associated to \a id.
   *
   * @param id id to set to false
   */
  void setFalse(const T id)
  {
    typename std::set<T>::iterator iter = std::set<T>::find(id);
    if (iter != std::set<T>::end())
      erase(iter);
  }

  /** Sets bit associated to \a id to a specific boolean value.
   *
   * @param id id to set or unset
   * @param value bit giving whether to set or unset
   */
  void setValue(const T id, bool value) {
    if (value)
      setTrue(id);
    else
      setFalse(id);
  }

  /** Use in printing the bit mask bit by bit.
   *
   * @param id bit to print
   * @return "t" or "f" whether bit is set or not.
   */
  const char* printBit(const T id) const
  {
    const typename std::set<T>::const_iterator iter = std::set<T>::find(id);
    return (iter != std::set<T>::end() ? "t" : "f");
  }
};


#endif /* MASK_HPP_ */