#!/usr/bin/env perl

use strict;
use warnings FATAL => 'all';
use feature qw(say);

use Test::Deep qw(eq_deeply);

sub parse_treedump {
	my $lines = shift;
	my @lines = @$lines;

	my %obj;
	my @stack;

	my $parse_next_line = sub {
		my $line = shift @lines;
		my $key_indicator = $line =~ /\|-/ ? '|-' : '`-';

		my $key_idx = index( $line, $key_indicator );

		my $level = @stack;
		my $key_level = $key_idx / 3;

		if ($key_level < $level) {
			pop @stack until $key_level == ($level = @stack);
		}

		my $current_obj = \%obj;
		$current_obj = $current_obj->{$_} foreach @stack;

		if ($line =~ /(\w+)\s=\s(.*)$/ && $key_level == $level) {
			$current_obj->{$1} = $2 eq 'undef' ? undef : $2;
		}

		elsif ($line =~ /(\w+)\s\(no\selements\)/) {
			$current_obj->{$1} = [ ];
		}

		elsif ($line =~ /(\w+)\s=$/) {
			$current_obj->{$1} = '';
		}

		elsif ($line =~ /(\w+)/ && $key_level == $level) {
			push @stack, $1;
			$current_obj->{$1} = { };
		}
	};

	$parse_next_line->() while @lines;

	return \%obj
}

my $expected_hash = {
	one      => 'two',
	three    => {
		four   => 'five',
		six    => 'seven',
		eight  => {
			nine => 'ten'
		},
		eleven => [ ],
		twelve => undef,
	},
	thirteen => 'fourteen'
};

my $lines = [];
while (<DATA>) {
	chomp;
	push @$lines, $_;
}
close DATA;
my $output_hash = parse_treedump($lines);

if (eq_deeply($output_hash, $expected_hash)) {
	say "OK";
}

1;

__DATA__
|- one = two
|- three
|  |- four = five
|  |- six = seven
|  |- eight
|  |  `- nine = ten
|  |- eleven (no elements)
|  `- twelve = undef
`- thirteen = fourteen