# To get readline line editing functionality, please install
# Term::ReadLine::Gnu (GPL) or Term::ReadLine::Perl (GPL, Artistic)
# from CPAN.

package readline;
use strict;
use warnings;
use Exporter 'import';
our @EXPORT_OK = qw( mal_readline );

use Term::ReadLine;

my $_rl = Term::ReadLine->new('Mal');
$_rl->ornaments(0);
#print "Using ReadLine implementation: " . $_rl->ReadLine() . "\n";
my $OUT = $_rl->OUT || \*STDOUT;
my $_history_loaded = 0;

my $history_file = $ENV{"HOME"} . "/.mal-history";

sub save_line {
    my ($line) = @_;
    open(my $fh, '>>', $history_file) or return;
    say $fh $line;
    close $fh;
}

sub load_history {
    open my $fh, $history_file or return;

    while(my $line = <$fh>)  {   
        chomp $line;
        $_rl->addhistory($line) if $line =~ /\S/;
    }

    close $fh;
}

sub mal_readline {
    my($prompt) = @_;
    my $line = undef;
    if (! $_history_loaded) {
        $_history_loaded = 1;
        load_history();
    }

    if (defined ($line = $_rl->readline($prompt))) {
        save_line($line);
        return $line;
    } else {
        return undef;
    }
}
1;