ocarina/include/core/tags/track.h

/**
 * Copyright 2014 (c) Anna Schumaker.
 */
#ifndef OCARINA_CORE_TAGS_TRACK_H
#define OCARINA_CORE_TAGS_TRACK_H

#include <core/tags/generic.h>
#include <core/tags/artist.h>
#include <core/tags/album.h>
#include <core/tags/genre.h>
#include <core/tags/library.h>


/** Structure used to represent dates. */
struct date {
	unsigned int day;   /**< Day of the month (1 - 31).   */
	unsigned int month; /**< Month of the year (1 - 12).  */
	unsigned int year;  /**< Number of years, Commen Era. */
	date() : day(0), month(0), year(0) {};
};


/**
 * The Track tag is used to store information about tracks that
 * have been added to the tag database.
 */
class Track : public GenericTag {
private:
	Album   *_album;   /**< Pointer to the Album containing this track.   */
	Artist  *_artist;  /**< Pointer to the Artist performing this track.  */
	Genre   *_genre;   /**< Pointer to the Genre describing this track.   */
	Library *_library; /**< Pointer to the Library containing this track. */

	unsigned int _count;  /**< Number of times this track has been played.*/
	unsigned int _length; /**< Length of this track (in seconds).         */
	unsigned int _track;  /**< Track number of this track.                */

	struct date _date; /**< Date that we last played this track.          */
	std::string _path; /**< Path of this track, relative to the Library.  */

public:
	/**
	 * Track constructor
	 *
	 * @param  album    The album containing this track.
	 * @param  artist   The artist performing this track.
	 * @param  genre    The genre describing this track.
	 * @param  library  The library containing this track.
	 * @param  filepath The path of this track, relative to the library root.
	 * @param  name     The name (title) of this track.
	 * @param  length   The length of this track (in seconds).
	 * @param  track    The track number of this track.
	 */
	Track(Album *, Artist *, Genre *, Library *, const std::string &,
	      const std::string &, unsigned int, unsigned int);

	/**
	 * Track copy constructor
	 *
	 * @param track  The Track tag that should be copied.
	 */
	Track(const Track &);

	Track();  /**< Track constructor. */
	~Track(); /**< Track destructor.  */


	Album   *album();   /**< @return Track::_album.   */
	Artist  *artist();  /**< @return Track::_artist.  */
	Genre   *genre();   /**< @return Track::_genre.   */
	Library *library(); /**< @return Track::_library. */

	unsigned int count();  /**< @return Track::_count.  */
	unsigned int length(); /**< @return Track::_length. */
	unsigned int track();  /**< @return Track::_track.  */


	/**
	 * @return A locale-dependent string containing the day this
	 *         track was last played, or "Never" if the track has
	 *         never been played.
	 */
	const std::string date() const;

	/** @return The full path of this track. */
	const std::string path() const;

	/**
	 * A track's primary key is the concatenation of the library index
	 * and the relative path.
	 *
	 * @return Track::_library->index() / Track::_path.
	 */
	const std::string primary_key() const;

	/** Increment Track::_count and set Track::_date to today's date. */
	void played();

	/**
	 * Compare two tracks based on last played date.
	 *
	 * @param  rhs  The other track to compare.
	 * @return < 0: lhs < rhs.
	 * @return   0: lhs == rhs.
	 * @return > 0: lhs > rhs;
	 */
	int compare_date(const Track *);


	/**
	 * Read track data from file.
	 *
	 * @param  file  The file to read from.
	 */
	void read(File &);

	/**
	 * Write track data to file.
	 *
	 * @param  file  The file to write to.
	 */
	void write(File &);
};

namespace tags
{
	/** Called to read the track_db from disk. */
	void init_track_db();

	/**
	 * Called to create a new Track tag.
	 *
	 * @param  album    The album containing this track.
	 * @param  artist   The artist performing this track.
	 * @param  genre    The genre describing this track.
	 * @param  library  The library containing this track.
	 * @param  filepath The path of this track, relative to the library root.
	 * @param  name     The name (title) of this track.
	 * @param  length   The length of this track (in seconds).
	 * @param  track    The track number of this track.
	 * @return A new Track tag, or NULL if this Track is already in
	 *         the track_db.
	 */
	Track *add_track(Album *, Artist *, Genre *, Library *,
			 const std::string &, const std::string &,
			 unsigned int, unsigned int);

	/**
	 * Called to look up a Track tag by tag index.
	 *
	 * @param  index  The index of the Track tag.
	 * @return A matching Track tag, or NULL.
	 */
	Track *get_track(const unsigned int);

	/**
	 * Called to remove a Track tag from the database.
	 *
	 * @param  track  The Track tag to be removed.
	 */
	void remove_track(Track *);

	/**
	 * Called to remove all tracks associated with a specific Library.
	 *
	 * @param  library  The Library tag that will be matched.
	 */
	void remove_library_tracks(Library *);

	/**
	 * Called to find the number of rows in the track_db,
	 * including NULL rows.
	 *
	 * @return The Database::actual_size() of the track_db.
	 */
	unsigned int track_size();

	/** Called to write the track_db to disk. */
	void commit_track_db();
}

#endif /* OCARINA_CORE_TAGS_TRACK_H */