package AI::Pathfinding::OptimizeMultiple::DataInputObj;

use strict;
use warnings;

use 5.012;

use MooX qw/late/;

use File::Path qw(mkpath);

use AI::Pathfinding::OptimizeMultiple::Scan;

use PDL (qw( pdl ));
use PDL::IO::FastRaw (qw( readfraw writefraw ));

our $VERSION = '0.0.11';

has start_board => (isa => 'Int', is => 'ro', required => 1);
has num_boards => (isa => 'Int', is => 'ro', required => 1);
has selected_scans => (isa => 'ArrayRef', is => 'ro', required => 1,
    default => sub {
        my ($self) = @_;

        return $self->_calc_selected_scan_list();
    },
    lazy => 1,
);

has _scan_ids_to_indexes => (isa => 'HashRef[Int]', is => 'ro',
    lazy => 1,
    default => sub {
        my ($self) = @_;

        my $scan_ids = $self->get_scan_ids_aref;
        return +{ map { $scan_ids->[$_] => $_} 0 .. $#$scan_ids };
    },
);

sub _slurp
{
    my $filename = shift;

    open my $in, "<", $filename
        or die "Could not open $filename";

    binmode $in;
    local $/;
    my $content = <$in>;
    close($in);
    return $content;
}

sub _read_text_ints_file
{
    my $self = shift;

    my $filename = shift;

    my $text = _slurp($filename);

    return [split(/[\n\r]+/, $text)];
}

# Number of selected scans.
sub _num_sel_scans
{
    my $self = shift;

    return scalar(@{$self->selected_scans()});
}

sub _gen_initial_scans_tensor
{
    my $self = shift;
    my $extra_dims = shift || [];

    return zeroes($self->num_boards(), $self->_num_sel_scans, @$extra_dims);
}

sub _should_update
{
    my ($self, $src_path, $dest_path) = @_;

    my @orig_stat = stat($src_path);
    my @proc_stat = stat($dest_path);

    return ((! @proc_stat) || ($orig_stat[9] > $proc_stat[9]));
}

# Number of numbers in the header of the solutions' iteration counts
my $NUM_NUMBERS_IN_HEADER = 3;

my $HEADER_START_BOARD_IDX = 0;
my $HEADER_NUM_BOARDS = 1;
my $HEADER_ITERATIONS_LIMIT = 2;

sub _get_scans_data_helper
{
    my $self = shift;

    my $selected_scans = $self->selected_scans();

    my $start_board = $self->start_board();

    my $scans_data = {};
    my $scans_lens_data = {};

    my $scan_idx = 0;

    my $data_dir = ".data-proc";
    my $lens_dir = ".data-len-proc";

    mkpath([$data_dir, $lens_dir]);

    foreach my $scan (@$selected_scans)
    {
        {
            my $dest_path = $data_dir . "/" . $scan->id();
            {
                if ($self->_should_update($scan->data_file_path(), $dest_path))
                {
                    my $data_s = _slurp($scan->data_file_path());
                    my @array = unpack("l*", $data_s);
                    if (($array[$HEADER_START_BOARD_IDX] != 1) ||
                        ($array[$HEADER_NUM_BOARDS] < $self->num_boards)
                    )
                    {
                        die "Incorrect file format in scan " . $scan->{'id'} . "!\n";
                    }

                    my $c = pdl(\@array);

                    writefraw($c, $dest_path);
                }
            }
            {
                my $start_idx = $NUM_NUMBERS_IN_HEADER + ($start_board - 1);
                my $scan_vec = readfraw($dest_path);
                $scans_data->{$scan->id()} = $scan_vec->slice(
                    $start_idx.":".($start_idx + $self->num_boards()-1)
                );
            }
        }
        {
            my $src = $scan->data_file_path();
            my $dest = "$lens_dir/" . $scan->id();

            if ($self->_should_update($src, $dest))
            {
                my $data_s = _slurp($src);

                my @iters = unpack("l*", $data_s);
                if ( ($iters[0] != 1) || ($iters[1] < $self->num_boards()) )
                {
                    die "Incorrect file format in scan " . $scan->id() . "!\n";
                }

                # Remove the header
                splice @iters, 0, $NUM_NUMBERS_IN_HEADER;

                my $c = pdl(
                    [\@iters,
                    $self->_read_text_ints_file(
                        "data/" . $scan->id() . ".fcs.moves.txt"
                    ),
                    $self->_read_text_ints_file(
                        "data/" . $scan->id() . ".fcpro.moves.txt"
                    ),
                    ]
                );

                writefraw($c, $dest);
            }
            {
                my $scan_vec = readfraw($dest);
                $scans_lens_data->{$scan->id()} = $scan_vec->slice(
                    sprintf(
                        "%d:%d,:,*",
                        ($start_board-1),
                        (($self->num_boards()-1)+($start_board-1))
                    )
                )->xchg(1,2);
            }
        }
    }
    continue
    {
        $scan_idx++;
    }

    return { 'scans' => $scans_data, 'with_lens' => $scans_lens_data };
}

sub _get_scans_data_generic
{
    my ($self, $id) = @_;

    return $self->_get_scans_data_helper()->{$id};
}

sub get_scans_iters_pdls
{
    my $self = shift;

    return $self->_get_scans_data_generic('scans');
}

sub get_scans_lens_iters_pdls
{
    my $self = shift;

    return $self->_get_scans_data_generic('with_lens');
}

sub _filter_scans_based_on_black_list_ids
{
    my ($scans, $black_list_ids) = @_;

    my %black_list = (map { /(\d+)/?($1 => 1) : () } @$black_list_ids);

    return
        [grep
            {
                !exists($black_list{$_->id()})
            }
            @$scans
        ];
}

sub _is_scan_suitable
{
    my ($self, $scan) = @_;

    my @stat = stat($scan->data_file_path());
    return
    (
        scalar(@stat)
            &&
        ($stat[7] >= 12 + ($self->num_boards() + $self->start_board() -1) * 4)
    );
}

sub _get_scans_registry_file_path
{
    return "scans.txt";
}

sub _get_all_scans_list_from_file
{
    my $self = shift;

    my @scans;

    my $scans_fn = $self->_get_scans_registry_file_path;

    open my $scans_fh, "<", $scans_fn
        or die "Could not open '$scans_fn' - $!.";
    while (my $line = <$scans_fh>)
    {
        chomp($line);
        my ($id, $cmd_line) = split(/\t/, $line);
        push @scans,
            AI::Pathfinding::OptimizeMultiple::Scan->new(
                id => $id,
                cmd_line => $cmd_line
            );
    }
    close($scans_fh);

    return \@scans;
}

sub _black_list_ids_list
{
    my $self = shift;

    open my $black_list_fh, "<", "scans-black-list.txt"
        or die "Could not open 'scans-black-list.txt'! $!.";
    my @black_list_ids = <$black_list_fh>;
    chomp(@black_list_ids);
    close($black_list_fh);

    return \@black_list_ids;
}

sub _suitable_scans_list
{
    my $self = shift;

    return
    [
        grep
        {
            $self->_is_scan_suitable($_)
        }
        @{$self->_get_all_scans_list_from_file()}
    ];
}

sub _calc_selected_scan_list
{
    my $self = shift;

    return
        _filter_scans_based_on_black_list_ids(
            $self->_suitable_scans_list(),
            $self->_black_list_ids_list(),
        )
}

sub _get_next_id_file_path
{
    return "next-id.txt";
}

sub get_next_id
{
    my ($self) = @_;

    my $id;

    my $fn = $self->_get_next_id_file_path;

    use autodie;

    open my $in, "<", $fn;
    $id = <$in>;
    chomp($id);
    close($in);

    open my $out, ">", $fn;
    print {$out} ($id+1);
    close($out);

    return $id;
}

sub get_prev_scans
{
    my ($self) = @_;

    my @prev_scans;

    my $scans_fn = $self->_get_scans_registry_file_path;

    open my $in, "<", $scans_fn
        or die "Could not open '$scans_fn' - $!.";;
    while (my $line = <$in>)
    {
        chomp($line);
        my ($scan_id, $cmd_line) = split(/\t/, $line);
        push @prev_scans, { 'id' => $scan_id, 'cmd_line' => $cmd_line };
    }
    close($in);

    return \@prev_scans;
}

sub _get_scan_cmd_line
{
    my $self = shift;
    my $args = shift;

    my $min_board = $args->{'min'} || 1;
    my $max_board = $args->{'max'} || 32_000;
    my $id = $args->{'id'};
    my $argv = $args->{'argv'};
    my @fc_num =
        (exists($args->{'freecells_num'})
            ?  ("--freecells-num" , $args->{'freecells_num'})
            : ()
        );
    my @variant =
        (exists($args->{'variant'})
            ? ("--variant", $args->{'variant'})
            : ()
        );

    return
    [
        qw(freecell-solver-fc-pro-range-solve),
        $min_board, $max_board, "20",
        @variant,
        qw(--total-iterations-limit 100000 --binary-output-to),
        "data/$id.data.bin",
        @$argv,
        @fc_num,
    ];
}

sub time_scan
{
    my $self = shift;
    my $args = shift;

    my $min_board = $args->{'min'} || 1;
    my $max_board = $args->{'max'} || 32_000;
    my $id = $args->{'id'};

    my $cmd_line = $self->_get_scan_cmd_line($args);

    open my $from_cmd, "-|", @$cmd_line
        or die "Could not start '@$cmd_line'";
    open my $fcs_out, ">", "data/$id.fcs.moves.txt";
    open my $fc_pro_out, ">", "data/$id.fcpro.moves.txt";
    $fcs_out->autoflush(1);
    $fc_pro_out->autoflush(1);
    while (my $line = <$from_cmd>)
    {
        print $line;
        chomp($line);
        if ($line =~ m{\A\[\[Num FCS Moves\]\]=(.*)\z}o)
        {
            print {$fcs_out} "$1\n";
        }
        elsif ($line =~ m{\A\[\[Num FCPro Moves\]\]=(.*)\z}o)
        {
            print {$fc_pro_out} "$1\n";
        }
    }
    close($from_cmd);
    close($fcs_out);
    close($fc_pro_out);
}

sub get_scan_ids_aref
{
    my $self = shift;

    return [map { $_->id() } @{ $self->selected_scans }];
}

sub lookup_scan_idx_based_on_id
{
    my ($self, $scan_id) = @_;

    my $idx = $self->_scan_ids_to_indexes->{$scan_id};
    if (!defined($idx))
    {
        die "Index '$idx' does not exist!";
    }

    return $idx;
}

1;

=pod

=head1 NAME

AI::Pathfinding::OptimizeMultiple::DataInputObj - handle the data input.

=head1 SUBROUTINES/METHODS

=head2 $self->get_next_id()

Retrieves the next scan ID and increment it.

=head2 $self->get_prev_scans()

Returns an array reference of previous scan hash-refs.

=head2 my $hash_ref = $self->get_scans_iters_pdls()

Returns the hash ref mapping scan IDs/names to iteration PDLs.

=head2 my $hash_ref = $self->get_scans_lens_iters_pdls()

Returns the hash ref mapping scan IDs/names to iteration+lengths PDLs.

=head2 $self->num_boards()

The number of boards.

=head2 $self->selected_scans()

An accessor for the selected scans.

=head2 $self->start_board()

The index of the board to start from.

=head2 $self->time_scan()

Times a new scan.

=head2 $self->get_scan_ids_aref()

Get an array reference of the scan IDs.

=head2 my $idx = $self->lookup_scan_idx_based_on_id($scan_id)

$scan_id is a string and lookup_scan_idx_based_on_id() looks up its index
in the scans.

=head1 COPYRIGHT AND LICENSE

Copyright (c) 2010 Shlomi Fish

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

=cut