//
// Created by Administrator on 2021/4/30.
//

#ifndef SYNTAXPARSER_ITEMCOLLECTION_H
#define SYNTAXPARSER_ITEMCOLLECTION_H

#include <fstream>
#include <iostream>
#include <algorithm>
#include <functional>


#include <Item.h>
#include <GrammarResourcePool.h>

class ItemCollectionManager;

class ItemCollection{

    int index = 0;

    std::map<size_t, Item *> items;

    std::vector<Item *> cache;

    GrammarResourcePool *pool;

    friend ItemCollectionManager;

    template <class T>
    inline void hash_combine(std::size_t& seed, const T& v) const
    {
        std::hash<T> hasher;
        seed ^= hasher(v) + 0x9e3779b9 + (seed<<6) + (seed>>2);
    }

    static bool compare_item_ptr(const Item* lhs, const Item* rhs);

public:

    explicit ItemCollection(GrammarResourcePool *pool) : pool(pool) {

    }

    [[nodiscard]] const std::vector<Item *> &getItems() const {
        return cache;
    }

    [[nodiscard]] int getIndex() const  {
        return index;
    }


    bool addItem(const Production *p_pdt, int dot_index, int terminator, bool generated = false);

    void CLOSURE();

    void print(std::wofstream &output) const;

    [[nodiscard]] size_t getHash() const;
};

#endif //SYNTAXPARSER_ITEMCOLLECTION_H