//
// Created by YuhangQ on 2021/9/24.
//

#ifndef INVODB_PAGE_MANAGER_H
#define INVODB_PAGE_MANAGER_H

#include <iostream>
#include <fstream>
#include <cstring>

class StoragePage {
public:
    void print();
    int next();
    int setNext(const int& nextPage);
    int* intArray();
    StoragePage() { memset(page, 0, sizeof(page)); }
    char& operator[] (int index) { return this->page[index]; }
    operator const char *() const { return this->page; }
    operator char *() { return this->page; }
private:
    char page[1024];
};

class PageManager {
public:
    static PageManager& Instance() {
        static PageManager instance;
        return instance;
    }
    static int loadDatabase(const char *filename);
    StoragePage getPage(const int &index);
    void setPage(const int &index, const StoragePage &page);
    int allocate();

private:
    std::fstream stream;

    // 私有化实现单例
    PageManager() {}
    ~PageManager() {}
    PageManager(const PageManager&);
    PageManager& operator=(const PageManager&);
};


#endif //INVODB_PAGE_MANAGER_H