use strict;
use warnings;
use feature 'say';
use FindBin;
use Data::Dump 'dd';
use autodie;
use Benchmark 'cmpthese';
 
use lib "$FindBin::Bin/lib";
use MyUnion 'wrap_ppunpo';

use Math::Geometry::Planar;

{                       ###### Demo data output block
    my @sets = (
        [[0,0],[0,2],[2,2],[2,0],[0,0]],
        [[0,0],[3,0],[3,1],[0,1],[0,0]],
        [[3,0],[3,2],[4,2],[4,0],[3,0]],
        [[0,2],[0,3],[1,3],[1,2],[0,2]],
    );
    say "\n**** Demo output for GPC:\n";

    my $clip_gpc_obj = Math::Geometry::Planar-> new;
    my $poly_gpc_obj = Math::Geometry::Planar-> new;

    $clip_gpc_obj-> points( $sets[ 0 ]);
    for ( 1.. 3 ) {
        $poly_gpc_obj-> points( $sets[ $_ ]);
        dd [ 
            map @{ $_-> polygons }, Gpc2Polygons( 
                GpcClip( 
                    'UNION', 
                    $poly_gpc_obj-> convert2gpc,
                    $clip_gpc_obj-> convert2gpc,
                )
            )
        ]
    }
    say "\n\n*** Demo output for POLYPACK:\n";
    dd wrap_ppunpo( @sets[ 0, $_ ]) for 1 .. 3;
}

####################### Benchmark 

my $clip_points = _get_data( 'c' );    # clipmask polygon points
my $poly_points = _get_data( 's' );    # sample polygon points

my $clip_gpc_obj = Math::Geometry::Planar-> new;
my $poly_gpc_obj = Math::Geometry::Planar-> new;
$clip_gpc_obj-> points( $clip_points );
$poly_gpc_obj-> points( $poly_points );
my $clip_gpc_struct = $clip_gpc_obj-> convert2gpc;
my $poly_gpc_struct = $poly_gpc_obj-> convert2gpc;

say "\n\n*** Benchmark (union of polygons with "
    . @$clip_points . ' and ' . @$poly_points . " points):\n";

cmpthese( -5, {
    GPC_lib => sub {
        my $union_gpc_struct = GpcClip( 
            'UNION', 
            $poly_gpc_struct,
            $clip_gpc_struct,
        );
        my ( $contour ) = Gpc2Polygons( $union_gpc_struct );
        return $contour-> polygons;
    },
    POLYPACK => sub {
        return wrap_ppunpo( $clip_points, $poly_points );
    },
});

sub _get_data {             # only simple wlr files expected!
    my $name = shift;

    open my $fh, '<', "sample/$name.wlr";
    <$fh>; <$fh>; <$fh>; 

    my @a;
    push @a, [ map { 0 + $_ } split ',', <$fh> ]
        until eof $fh;
    return \@a
}

__END__