/*
 * Copyright 2013 (c) Anna Schumaker.
 */
#include <playlist.h>
#include <stdlib.h>

Playlist :: Playlist()
	 : flags(0), cur(-1)
{
}

Playlist :: Playlist(playlist_flags f)
	 : flags(f), cur(-1)
{
}

Playlist :: ~Playlist()
{
}

void Playlist :: write(File &f)
{
	f << flags << " " << tracks.size();
	for (unsigned int i = 0; i < tracks.size(); i++)
		f << " " << tracks[i];
}

void Playlist :: read(File &f)
{
	unsigned int n;
	f >> flags >> n;
	tracks.resize(n);
	for (unsigned int i = 0; i < n; i++)
		f >> tracks[i];
}

void Playlist :: set_flag(playlist_flags f)
{
	flags |= f;
}

void Playlist :: unset_flag(playlist_flags f)
{
	flags &= ~f;
}

const unsigned int Playlist :: get_flags()
{
	return flags;
}

unsigned int Playlist :: add(unsigned int track_id)
{
	tracks.push_back(track_id);
	return tracks.size() - 1;
}

void Playlist :: del(unsigned int plist_id)
{
	tracks.erase(tracks.begin() + plist_id);
}

unsigned int Playlist :: size()
{
	return tracks.size();
}

unsigned int Playlist :: next()
{
	unsigned int res;

	if (tracks.size() == 1)
		cur = 0;
	else if (flags & PL_RANDOM)
		cur += rand() % (tracks.size() / 2) + 1;
	else
		cur++;

	if (cur >= tracks.size())
		cur -= tracks.size();

	res = tracks[cur];
	if (!(flags & PL_LOCKED)) {
		tracks.erase(tracks.begin() + cur);
		cur--;
	}
	return res;
}