#ifndef filemanager_H
#define filemanager_H

#include <string>
#include <map>
#include <vector>
#include <utility>

#include "TChain.h"

typedef long int runnumber_id;
typedef std::string period_id;


struct DatasetInformation
{
    std::string name;
    std::string regex;
    std::string path;
};


class FileManager
{
public:
    typedef std::multimap<runnumber_id, std::string> database_type;
    typedef std::pair<database_type::const_iterator, database_type::const_iterator> bi_iterator;

    /**
     * the constructor take an identifier of the data, actually it can be:
     *
     * - DATA
     * - DATAEGAMMA
     * - DATAL1CALO
     * - MCJF17
     * - MCGAMGAM15
     * - MCGAMGAM7
     **/

    explicit FileManager(const std::string dataset_name = "DATA");
    explicit FileManager(const DatasetInformation & dataset_information);


    /**
     * all these functions (probably you don't need them) return a couple of
     * iterators:
     * std::pair<database_type::const_iterator, database_type::const_iterator>
     * the first value is the begin(), the second the end() of the space you
     * want to iterate. Example:
     * 
     * FileManager::bi_iterator startend = file_manager.get_iterator_from(0);
     * FileManager::database_type::const_iterator begin = startend.first;
     * FileManager::database_type::const_iterator end = startend.second;
     * FileManager::database_type::const_iterator it = begin;
     * for (; it != end; ++it)
     *   std::cout << "run: " << it->first << " file: " << it->second << std::endl;
     *
     **/
    bi_iterator get_iterator(runnumber_id runnumber) const;
    bi_iterator get_iterator_all() const;
    bi_iterator get_iterator_from(runnumber_id from) const;
    bi_iterator get_iterator_to(runnumber_id to) const;
    bi_iterator get_iterator_fromto(runnumber_id from,
				    runnumber_id to) const;
    bi_iterator get_iterator_period(period_id period) const;


    /**
     * all these functions return a std::vector<std::string> of filenames
     **/
    std::vector<std::string> get_filename(runnumber_id runnumber) const;
    std::vector<std::string> get_filename_all() const;
    std::vector<std::string> get_filename_from(runnumber_id from) const;
    std::vector<std::string> get_filename_to(runnumber_id to) const;
    std::vector<std::string> get_filename_fromto(runnumber_id from,
						 runnumber_id to) const;
    std::vector<std::string> get_filename_period(period_id period) const;
    

    /**
     * probably this is what you want. These functions return a TChain*
     * ready to be used.
     **/
    TChain* get_chain(runnumber_id runnumber) const;
    TChain* get_chain_all() const;
    TChain* get_chain_from(runnumber_id from) const;
    TChain* get_chain_to(runnumber_id to) const;
    TChain* get_chain_fromto(runnumber_id from,
			     runnumber_id to) const;
    TChain* get_chain_period(period_id period) const;
    
    
private:
    database_type database;
    std::map<std::string, DatasetInformation> datasets_info;
    DatasetInformation dataset_info;
    runnumber_id get_runnumber_from_filename(const std::string);
    void find_files();
    void InitDatasetInformation();
    void AddDatasetInformation(const DatasetInformation & dataset_information);
};


#endif