remwharead/include/uri.hpp

/*  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_URI_HPP
#define REMWHAREAD_URI_HPP

#include <string>

namespace remwharead
{
    using std::string;

    /*!
     *  @brief  A processed HTML page.
     *
     *  @return true if successful, when cast to bool.
     *
     *  @since  0.7.0
     *
     *  @headerfile uri.hpp remwharead/uri.hpp
     */
    typedef struct html_extract
    {
        bool successful = false;
        string error;
        string title;
        string description;
        string fulltext;

        operator bool();
    } html_extract;

    /*!
     *  @brief  The result of the call to the archive service.
     *
     *  @return true if successful, when cast to bool.
     *
     *  @since  0.7.0
     *
     *  @headerfile uri.hpp remwharead/uri.hpp
     */
    typedef struct archive_answer
    {
        bool successful = false;
        string error;
        string uri;

        operator bool();
    } archive_answer;

    /*!
     *  @brief  Download, archive and process an %URI.
     *
     *  @since  0.6.0
     *
     *  @headerfile uri.hpp remwharead/uri.hpp
     */
    class URI
    {
    public:
        //! Construct object and set URL.
        explicit URI(const string &uri);
        ~URI();

        //! Download %URI and extract title, description and full text.
        const html_extract get();

        //! Save %URI in archive and return archive-URI.
        const archive_answer archive();

    protected:
        string _uri;

        //! Make a HTTP(S) request.
        const string make_request(const string &uri,
                                  bool archive = false) const;

        //! Extract the title from an HTML page.
        const string extract_title(const string &html);

        //! Extract the description from an HTML page.
        const string extract_description(const string &html);

        //! Removes HTML tags and superflous spaces from an HTML page.
        const string strip_html(const string &html);

        /*!
         *  @brief  Remove HTML tags.
         *
         *  @param  html HTML page.
         *  @param  tag  If set, only remove this tag.
         */
        const string remove_html_tags(const string &html,
                                      const string &tag = "");

        //! Convert HTML entities to UTF-8.
        const string unescape_html(const string &html);

        //! Replace newlines with spaces.
        const string remove_newlines(string text);
    };
}

#endif  // REMWHAREAD_URI_HPP