ocarina/include/database.h

/*
 * Copyright 2013 (c) Anna Schumaker.
 */
#ifndef OCARINA_DATABASE_H
#define OCARINA_DATABASE_H

#include <file.h>
#include <print.h>

#include <map>
#include <set>
#include <vector>


class DatabaseEntry {
public:
	bool valid;

	DatabaseEntry();
	virtual std::string primary_key() = 0;
	virtual void write(File &) = 0;
	virtual void read(File &) = 0;
};


class IndexEntry : public DatabaseEntry {
public:
	std::string key;
	std::set<unsigned int> values;

	IndexEntry();
	IndexEntry(const std::string &, unsigned int);
	~IndexEntry();
	std::string primary_key();
	void write(File &);
	void read(File &);
#ifdef CONFIG_TEST
	void print();
#endif /* CONFIG_TEST */
	void insert(unsigned int);
	void remove(unsigned int);
};


template <class T>
class Database {
private:
	std::vector<T> _db;
	std::map<const std::string, unsigned int> _keys;
	unsigned int _size;
	bool _autosave;
	File _file;

	void autosave();

public:
	typedef typename std::vector<T>::iterator iterator;
	typedef typename std::vector<T>::const_iterator const_iterator;

	Database(std::string, bool);
	~Database();
	void save();
	void load();

	unsigned int insert(T);
	void remove(unsigned int);
	unsigned int size();
	unsigned int actual_size();

	iterator begin();
	iterator end();
	iterator next(iterator &);

	iterator at(unsigned int);
	iterator find(const std::string &);
};

static inline void index_insert(Database<IndexEntry> &db,
				const std::string &key,
				unsigned int val)
{
	Database<IndexEntry>::iterator it = db.find(key);
	if (it == db.end()) {
		db.insert(IndexEntry(key, val));
	} else
		it->insert(val);
}

static inline void index_remove(Database<IndexEntry> &db,
				const std::string &key,
				unsigned int val)
{
	Database<IndexEntry>::iterator it = db.find(key);
	if (it != db.end()) {
		it->remove(val);
		if (it->values.size() == 0)
			db.remove(it - db.begin());
	}
}

#include "database.hpp"

#endif /* OCARINA_DATABASE_H */