/*
    Copyright (C) 2015-2016 Carl Hetherington <cth@carlh.net>

    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; either version 2 of the License, or
    (at your option) any later version.

    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, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include "raw_convert.h"
#include "image_filename_sorter.h"
#include <boost/filesystem.hpp>
#include <boost/foreach.hpp>
#include <iostream>

using std::list;

bool
ImageFilenameSorter::operator() (boost::filesystem::path a, boost::filesystem::path b)
{
	std::list<int> na = extract_numbers (a);
	std::list<int> nb = extract_numbers (b);
	if (na.empty() || nb.empty()) {
		return a.string() < b.string();
	}

	if (na.size() != nb.size()) {
		/* Just use the first one */
		return na.front() < nb.front();
	}

	std::list<int>::const_iterator i = na.begin ();
	std::list<int>::const_iterator j = nb.begin ();

	while (i != na.end()) {
		if (*i != *j) {
			return *i < *j;
		}
		++i;
		++j;
	}

	/* All the same */
	return false;

}

list<int>
ImageFilenameSorter::extract_numbers (boost::filesystem::path p)
{
	p = p.leaf ();

	std::list<std::string> numbers;

	std::string current;
	for (size_t i = 0; i < p.string().size(); ++i) {
		if (isdigit (p.string()[i])) {
			current += p.string()[i];
		} else {
			if (!current.empty ()) {
				numbers.push_back (current);
				current.clear ();
			}
		}
	}

	if (!current.empty ()) {
		numbers.push_back (current);
	}

	std::list<int> numbers_as_int;
	BOOST_FOREACH (std::string i, numbers) {
		numbers_as_int.push_back (raw_convert<int> (i));
	}

	return numbers_as_int;
}