/*  This file is part of remwharead.
 *  Copyright © 2019 tastytea <tastytea@tastytea.de>
 *
 *  This program 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, version 3.
 *
 *  This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef REMWHAREAD_SQLITE_HPP
#define REMWHAREAD_SQLITE_HPP

#include <Poco/Data/Session.h>
#include <chrono>
#include <experimental/filesystem>
#include <list>
#include <memory>
#include <string>
#include <vector>

namespace remwharead
{
namespace fs = std::experimental::filesystem;
using std::string;
using std::vector;
using std::chrono::system_clock;
using time_point = system_clock::time_point;
using std::list;
using Poco::Data::Session;

/*!
 *  @brief  Store and retrieve files from/to SQLite.
 *
 *  @since  0.6.0
 *
 *  @headerfile sqlite.hpp remwharead/sqlite.hpp
 */
class Database
{
public:
    /*!
     *  @brief  Describes a database entry.
     *
     *  @since  0.6.0
     *
     *  @headerfile sqlite.hpp remwharead/sqlite.hpp
     */
    struct entry
    {
        string uri;
        string archive_uri;
        time_point datetime;
        vector<string> tags;
        string title;
        string description;
        string fulltext;

        /*!
         *  @brief  Returns true if date and time are equal.
         *
         *  @since  0.6.0
         */
        friend bool operator ==(const Database::entry &a,
                                const Database::entry &b);

        /*!
         *  @brief  The full text in one line.
         *
         *  @since  0.6.0
         */
        [[nodiscard]]
        string fulltext_oneline() const;
    };

    /*!
     *  @brief  Connects to the database and creates it if necessary.
     *
     *  @since  0.6.0
     */
    Database();

    /*!
     *  @brief  Returns true if connected to the database.
     *
     *  @since  0.6.0
     */
    explicit operator bool() const;

    /*!
     *  @brief  Store a Database::entry in the database.
     *
     *  @since  0.6.0
     */
    void store(const entry &data) const;

    /*!
     *  @brief  Retrieve a list of Database::entry from the database.
     *
     *  @since  0.6.0
     */
    [[nodiscard]]
    list<entry> retrieve(const time_point &start = time_point(),
                         const time_point &end = system_clock::now()) const;

    /*!
     *  @brief  Remove all entries with this URI from database.
     *
     *  @return Number of removed entries.
     *
     *  @since  0.9.0
     */
    size_t remove(const string &uri);

    /*!
     *  @brief  Returns tags as comma separated string.
     *
     *  @since  0.9.0
     */
    [[nodiscard]]
    static string tags_to_string(const vector<string> &tags);

private:
    fs::path _dbpath;
    std::unique_ptr<Session> _session;
    bool _connected;

    [[nodiscard]]
    static fs::path get_data_home();
};
} // namespace remwharead

#endif  // REMWHAREAD_SQLITE_HPP