session.hh

   1 /*
   2  * Copyright (c) 2021, S. Gilles <sgilles@sgilles.net>
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software
   5  * for any purpose with or without fee is hereby granted, provided
   6  * that the above copyright notice and this permission notice appear
   7  * in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
  10  * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
  11  * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
  12  * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
  13  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
  14  * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  15  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  16  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18 #ifndef SESSION_H
  19 #define SESSION_H
  20
  21 #include <filesystem>
  22 #include <optional>
  23 #include <map>
  24 #include <set>
  25 #include <variant>
  26 #include <vector>
  27
  28 #include "card.hh"
  29
  30 /* What's currently going on */
  31 enum class Currently_doing { Viewing_A, Viewing_B, Finished, Trivial };
  32
  33 /*
  34  * This holds the abstract information about a review session: a list of
  35  * cards scheduled for review and what action has been taken on each card.
  36  *
  37  * Thankfully rule-of-zero-compliant.
  38  */
  39 class Session {
  40         public:
  41                 Session(const std::filesystem::path& data_dir);
  42
  43                 /* A changing (but not strongly random) value per-run. Used by Card in shuffled ordering */
  44                 static std::string salt;
  45
  46                 /*
  47                  * A card at level j takes between timing_data[j].first
  48                  * and timing_data[j].second days to review next. Not
  49                  * computed because I might want to fiddle with it.
  50                  */
  51                 static constexpr std::pair<int, int> timing_data[13] = {
  52                         /* */
  53                         std::make_pair(0, 0),     /* */
  54                         std::make_pair(1, 1),     /* */
  55                         std::make_pair(1, 2),     /* */
  56                         std::make_pair(2, 3),     /* */
  57                         std::make_pair(3, 5),     /* */
  58                         std::make_pair(5, 8),     /* */
  59                         std::make_pair(8, 13),    /* */
  60                         std::make_pair(13, 21),   /* */
  61                         std::make_pair(21, 34),   /* */
  62                         std::make_pair(34, 55),   /* */
  63                         std::make_pair(55, 89),   /* */
  64                         std::make_pair(89, 144),  /* */
  65                         std::make_pair(144, 233), /* */
  66                 };
  67
  68                 /* Are the any cards to review in this session? */
  69                 bool have_cards_to_review() const;
  70
  71                 /* What's going on right now? */
  72                 Currently_doing get_current_action() const;
  73
  74                 /* Get the A-side of the card that's being looked at */
  75                 std::optional<const std::string> get_current_A_side() const;
  76
  77                 /* Get the B-side of the card that's being looked at */
  78                 std::optional<const std::string> get_current_B_side() const;
  79
  80                 /* Get something like "19/23" */
  81                 const std::string get_progress_string() const;
  82
  83                 /* Get something like "Finished. 10 passed, 3 failed" */
  84                 const std::string get_statistics() const;
  85
  86                 /* Get something like "Already marked as passed" */
  87                 const std::string get_previously_seen_string() const;
  88
  89                 /* Are there cards after this one? */
  90                 bool have_next_card() const;
  91
  92                 /* Are there cards before this one? */
  93                 bool have_prev_card() const;
  94
  95                 /* Flip the current card over */
  96                 void flip_current_card();
  97
  98                 /* Mark the current card as having had some review action taken */
  99                 void mark_current_card_as(Review_status review_status);
 100
 101                 /* Move to the next card */
 102                 void move_next_card();
 103
 104                 /* Move to the previous card */
 105                 void move_prev_card();
 106
 107                 /* Write out new levels and schedule files according to this session's progress */
 108                 void update_cards_on_disk();
 109
 110         private:
 111                 /* Something like "~/.data/sispare" */
 112                 const std::filesystem::path data_dir;
 113
 114                 /* When this session was started */
 115                 std::chrono::system_clock::time_point session_start;
 116
 117                 /* What the UI should show right now */
 118                 Currently_doing current_action;
 119
 120                 /* All the cards that are due for review this session. */
 121                 std::set<Card> cards;
 122
 123                 /* Our iterator into cards */
 124                 std::set<Card>::iterator cards_it;
 125
 126                 /* ... and the actual index */
 127                 std::size_t it_index;
 128
 129                 /* What happened to each card? Indexed by path for use by update_cards_on_disk. */
 130                 std::map<std::filesystem::path, Review_status> card_status;
 131
 132                 /* The schedule files that may need to be updated if we review some cards */
 133                 std::vector<std::filesystem::path> schedule_files_to_clean;
 134
 135                 /* The cards which we failed reading; therefore cards we should delete */
 136                 std::set<std::filesystem::path> cards_to_delete;
 137 };
 138
 139 #endif