src/song_list.h

   1 /***************************************************************************
   2  *   Copyright (C) 2008-2016 by Andrzej Rybczak                            *
   3  *   electricityispower@gmail.com                                          *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
  19  ***************************************************************************/
  20
  21 #ifndef NCMPCPP_SONG_LIST_H
  22 #define NCMPCPP_SONG_LIST_H
  23
  24 #include <boost/range/detail/any_iterator.hpp>
  25 #include "curses/menu.h"
  26 #include "song.h"
  27 #include "utility/const.h"
  28
  29 struct SongProperties
  30 {
  31         enum class State { Undefined, Const, Mutable };
  32
  33         SongProperties()
  34                 : m_state(State::Undefined)
  35         { }
  36
  37         SongProperties &assign(NC::List::Properties *properties_, MPD::Song *song_)
  38         {
  39                 m_state = State::Mutable;
  40                 m_properties = properties_;
  41                 m_song = song_;
  42                 return *this;
  43         }
  44
  45         SongProperties &assign(const NC::List::Properties *properties_, const MPD::Song *song_)
  46         {
  47                 m_state = State::Const;
  48                 m_const_properties = properties_;
  49                 m_const_song = song_;
  50                 return *this;
  51         }
  52
  53         const NC::List::Properties &properties() const
  54         {
  55                 assert(m_state != State::Undefined);
  56                 return *m_const_properties;
  57         }
  58         const MPD::Song *song() const
  59         {
  60                 assert(m_state != State::Undefined);
  61                 return m_const_song;
  62         }
  63
  64         NC::List::Properties &properties()
  65         {
  66                 assert(m_state == State::Mutable);
  67                 return *m_properties;
  68         }
  69         MPD::Song *song()
  70         {
  71                 assert(m_state == State::Mutable);
  72                 return m_song;
  73         }
  74
  75 private:
  76         State m_state;
  77
  78         union {
  79                 NC::List::Properties *m_properties;
  80                 const NC::List::Properties *m_const_properties;
  81         };
  82         union {
  83                 MPD::Song *m_song;
  84                 const MPD::Song *m_const_song;
  85         };
  86 };
  87
  88 template <Const const_>
  89 using SongIteratorT = boost::range_detail::any_iterator<
  90         typename std::conditional<
  91                 const_ == Const::Yes,
  92                 const SongProperties,
  93                 SongProperties>::type,
  94         boost::random_access_traversal_tag,
  95         typename std::conditional<
  96                 const_ == Const::Yes,
  97                 const SongProperties &,
  98                 SongProperties &>::type,
  99         std::ptrdiff_t
 100         >;
 101
 102 typedef SongIteratorT<Const::No> SongIterator;
 103 typedef SongIteratorT<Const::Yes> ConstSongIterator;
 104
 105 struct SongList
 106 {
 107         virtual SongIterator currentS() = 0;
 108         virtual ConstSongIterator currentS() const = 0;
 109         virtual SongIterator beginS() = 0;
 110         virtual ConstSongIterator beginS() const = 0;
 111         virtual SongIterator endS() = 0;
 112         virtual ConstSongIterator endS() const = 0;
 113
 114         virtual std::vector<MPD::Song> getSelectedSongs() = 0;
 115 };
 116
 117 inline SongIterator begin(SongList &list) { return list.beginS(); }
 118 inline ConstSongIterator begin(const SongList &list) { return list.beginS(); }
 119 inline SongIterator end(SongList &list) { return list.endS(); }
 120 inline ConstSongIterator end(const SongList &list) { return list.endS(); }
 121
 122 struct SongMenu: NC::Menu<MPD::Song>, SongList
 123 {
 124         SongMenu() { }
 125         SongMenu(NC::Menu<MPD::Song> &&base)
 126         : NC::Menu<MPD::Song>(std::move(base)) { }
 127
 128         virtual SongIterator currentS() override;
 129         virtual ConstSongIterator currentS() const override;
 130         virtual SongIterator beginS() override;
 131         virtual ConstSongIterator beginS() const override;
 132         virtual SongIterator endS() override;
 133         virtual ConstSongIterator endS() const override;
 134
 135         virtual std::vector<MPD::Song> getSelectedSongs() override;
 136 };
 137
 138 #endif // NCMPCPP_SONG_LIST_H