/*
* This file is part of pgn-extract: a Portable Game Notation (PGN) extractor.
* Copyright (C) 1994-2019 David J. Barnes
*
* pgn-extract is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* pgn-extract is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with pgn-extract. If not, see <http://www.gnu.org/licenses/>.
*
* David J. Barnes may be contacted as d.j.barnes@kent.ac.uk
* https://www.cs.kent.ac.uk/people/staff/djb/
*/
/* Define a type to hold hash values of interest.
* This is used both to aid in duplicate detection
* and in finding positional variations.
*/
#ifndef HASHING_H
#define HASHING_H
typedef struct HashLog {
/* Store both the final position hash value and
* the cumulative hash value for a game.
*/
HashCode final_hash_value;
HashCode cumulative_hash_value;
/* Record the file list index for the file this game was first found in. */
unsigned file_number;
struct HashLog *next;
} HashLog;
/*
* A structure for counting the number of times a position arises
* in a game.
*/
typedef struct PositionCount {
HashCode hash_value;
Colour to_move;
unsigned short castling_rights;
Rank ep_rank;
Col ep_col;
unsigned count;
struct PositionCount *next;
} PositionCount;
void init_duplicate_hash_table(void);
void clear_duplicate_hash_table(void);
const char *previous_occurance(Game game_details, unsigned plycount);
Boolean check_for_only_repetition(PositionCount *position_counts);
Boolean update_position_counts(PositionCount *position_counts, const Board *board);
void free_position_count_list(PositionCount *position_counts);
PositionCount *new_position_count_list(const Board *board);
PositionCount *copy_position_count_list(PositionCount *original);
#endif // HASHING_H