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use strict;
use warnings;

use Test::More;

plan tests => 16;

my $CLASS = 'Tree::Binary2';
use_ok( $CLASS )
    or Test::More->builder->BAILOUT( "Cannot load $CLASS" );

my $c;
my @order;
sub convert {
    my $c = shift;
    my @l;
    while ( my $n = $c->() ) {
        push @l, $n;
    }
    return @l;
}

{
    my $tree = $CLASS->new( 'A' )
                     ->left(
                             $CLASS->new( 'B' )
                                   ->left(
                                       $CLASS->new( 'C' )
                                   )
                                   ->right(
                                       $CLASS->new( 'D' )
                                   )
                     )
                     ->right(
                             $CLASS->new( 'E' )
                                   ->left(
                                       $CLASS->new( 'F' )
                                   )
                                   ->right(
                                       $CLASS->new( 'G' )
                                   )
                     )
                ;

    @order = $tree->traverse( $tree->IN_ORDER );
    is_deeply(
        [ map { $_->value } @order ],
        [ qw( C B D A F E G ) ],
        "The tree's ordering for in-order traversal is correct",
    );

    is_deeply(
        [ map { $_->value } $tree->traverse() ],
        [ qw( A B C D E F G ) ],
        "pre-order traversal works correctly",
    );

    @order = convert( $c = $tree->traverse() );
    is_deeply(
        [ map { $_->value } @order ],
        [ qw( A B C D E F G ) ],
        "pre-order traversal works correctly",
    );

    @order = map { $_ -> value } convert( $c = $tree->traverse( $tree->PRE_ORDER ) );
    is_deeply(
        [ @order ],
        [ qw( A B C D E F G ) ],
        "pre-order traversal works correctly",
    );

    @order = convert( $c = $tree->traverse( $tree->IN_ORDER ) );
    is_deeply(
        [ map { $_->value } @order ],
        [ qw( C B D A F E G ) ],
        "The tree's ordering for in-order traversal is correct",
    );

    @order = map { $_->value } convert( $c = $tree->traverse( $tree->POST_ORDER ) );
    is_deeply(
        [ @order ],
        [ qw( C D B F G E A ) ],
        "post-order traversal works correctly",
    );

    @order = convert( $c = $tree->traverse( $tree->LEVEL_ORDER ) );
    is_deeply(
        [ map { $_->value } @order ],
        [ qw( A B E C D F G ) ],
        "level-order traversal works correctly",
    );

    my $mirror = $tree->clone->mirror;
    my @clone_order = $mirror->traverse( $mirror->IN_ORDER );
    is_deeply(
        [ map { $_->value } @clone_order ],
        [ qw( G E F A D B C ) ],
        "The mirror's ordering for in-order traversal is correct",
    );

}

{
    my $tree = $CLASS->new(4)
        ->left(
            $CLASS->new(20)
                ->left(
                    $CLASS->new(1)
                        ->right(
                            $CLASS->new(10)
                                ->left($CLASS->new(5))
                        )
                )
                ->right(
                    $CLASS->new(3)
                )
        )
        ->right(
            $CLASS->new(6)
                ->left(
                    $CLASS->new(5)
                        ->right(
                            $CLASS->new(7)
                                ->left( $CLASS->new(90) )
                                ->right( $CLASS->new(91) )
                        )
                )
        )
    ;

    my @results = map { $_->value } $tree->traverse( $tree->IN_ORDER );

    is_deeply(
        [ @results ],
        [ 1, 5, 10, 20, 3, 4, 5, 90, 7, 91, 6 ],
        "The tree's ordering for in-order traversal is correct",
    );

    my $mirror = $tree->clone->mirror;
    my @m_results = map { $_->value } $mirror->traverse( $mirror->IN_ORDER );

    is_deeply(
        [ @m_results ],
        [ reverse @results ],
        "... the in-order traversal of the mirror is the reverse of the in-order traversal of the original tree",
    );

    @order = map { $_->value } convert( $c = $tree->traverse() );
    is_deeply(
        [ @order ],
        [ 4, 20, 1, 10, 5, 3, 6, 5, 7, 90, 91 ],
        "pre-order traversal works correctly",
    );

    @order = convert( $c = $tree->traverse( $tree->PRE_ORDER ) );
    is_deeply(
        [ map { $_->value } @order ],
        [ 4, 20, 1, 10, 5, 3, 6, 5, 7, 90, 91 ],
        "pre-order traversal works correctly",
    );

    @order = map { $_->value } convert( $c = $tree->traverse( $tree->IN_ORDER ) );
    is_deeply(
        [ @order ],
        [ 1, 5, 10, 20, 3, 4, 5, 90, 7, 91, 6 ],
        "The tree's ordering for in-order traversal is correct",
    );

    @order = convert( $c = $tree->traverse( $tree->POST_ORDER ) );
    is_deeply(
        [ map { $_->value } @order ],
        [ 5, 10, 1, 3, 20, 90, 91, 7, 5, 6, 4 ],
        "post-order traversal works correctly",
    );

    @order = convert( $c = $tree->traverse( $tree->LEVEL_ORDER ) );
    is_deeply(
        [ map { $_->value } @order ],
        [ 4, 20, 6, 1, 3, 5, 10, 7, 5, 90, 91 ],
        "level-order traversal works correctly",
    );
}