book.h

/*
 * Copyright (C) 1999-2000  Shane Hudson
 * Copyright (C) 2017  Fulvio Benini
 
 * This file is part of Scid (Shane's Chess Information Database).
 *
 * Scid 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.
 *
 * Scid 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 Scid.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
 
#ifndef SCID_ECO_BOOK_H
#define SCID_ECO_BOOK_H
 
#include "scid/core/error.h"
#include "scid/eco/code.h"
#include <filesystem>
#include <memory>
#include <string>
#include <string_view>
#include <unordered_map>
#include <vector>
 
namespace scid::core {
class Position;
}
 
namespace scid::eco {
 
using Error = scid::core::errorT;
using Position = scid::core::Position;
 
inline constexpr Error OK = scid::core::OK;
inline constexpr Error ERROR_FileOpen = scid::core::ERROR_FileOpen;
inline constexpr Error ERROR_Corrupt = scid::core::ERROR_Corrupt;
 
class Book {
public:
    struct Line {
        std::string_view code;
        std::string_view name;
        std::string_view moves;
    };
 
private:
    struct BookData {
        std::unique_ptr<char[]> compactStr;
        std::unique_ptr<char[]> comment;
 
        BookData(char* compact, char* comm)
            : compactStr(compact), comment(comm) {}
    };
 
    std::unordered_multimap<unsigned, BookData> pos_;
    std::vector<const char*> comments_;
    unsigned lineCount_ = 0;
    unsigned leastMaterial_ = 32; // The smallest amount of material in any
                                 // position in the book. In the range 0..32.
 
public:
    static std::pair<Error, Book> load(const std::filesystem::path& path);
 
    std::string_view findEcoString(const Position& position) const;
 
    Code findEco(const Position& position) const;
 
    std::vector<Line> linesWithPrefix(std::string_view ecoPrefix) const;
 
    unsigned lineCount() const { return lineCount_; }
    unsigned fewestPieces() const { return leastMaterial_; }
    size_t size() const { return pos_.size(); }
};
 
} // namespace scid::eco
 
#endif // SCID_ECO_BOOK_H