/*
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * Copyright 2019 Danny Robson <danny@nerdcruft.net>
 */

#include "emory/chunk/map.hpp"
#include "emory/chunk/params.hpp"

#include <cruft/util/io.hpp>
#include <cruft/util/view.hpp>
#include <cruft/util/parse/value.hpp>

#include <algorithm>
#include <iostream>
#include <compare>


///////////////////////////////////////////////////////////////////////////////
enum {
    ARG_SELF,
    ARG_BITS,
    ARG_WINDOW,
    ARGS_MINIMUM,
    ARGS_INPUT,

    NUM_ARGS,
};


//-----------------------------------------------------------------------------
static
std::strong_ordering
region_ordering (
    emory::chunk::region const &a,
    emory::chunk::region const &b
) {
    if (auto const cmp = a.size () <=> b.size (); cmp != 0)
        return cmp;
    for (int i = 0; i < std::ssize (a.digest); ++i)
        if (auto const cmp = a.digest[i] <=> b.digest[i]; cmp != 0)
            return cmp;
    return std::strong_ordering::equal;
}


static bool region_less (emory::chunk::region const &a, emory::chunk::region const &b)
{
    return region_ordering (a, b) < 0;
}


static bool region_equal (emory::chunk::region const &a, emory::chunk::region const &b)
{
    return region_ordering (a, b) == 0;
}


//static bool overlap (emory::chunk::region const &a, emory::chunk::region const &b)
//{
//    return a.offset.first < b.offset.second &&
//           b.offset.first < a.offset.second;
//}


//-----------------------------------------------------------------------------
int main (int argc, char const **argv)
{
    if (argc != NUM_ARGS) {
        std::cerr << "usage: " << argv[ARG_SELF] << " <bits> <window> <minimum> <input>\n";
        return EXIT_FAILURE;
    }

    emory::chunk::params const p {
        .bits    = cruft::parse::from_string<std::size_t> (argv[ARG_BITS  ]),
        .window  = cruft::parse::from_string<std::size_t> (argv[ARG_WINDOW]),
        .minimum = cruft::parse::from_string<std::ptrdiff_t> (argv[ARGS_MINIMUM]),
    };

    cruft::mapped_file data (argv[ARGS_INPUT]);
    emory::chunk::map src (data, p);

    std::cout << src.size () << " chunks\n";
}