Add Plang plugin

Plugins/Plang.pm

@@ -0,0 +1,66 @@
+# File: Plang.pm
+# Author: pragma-
+#
+# Purpose: Simplified scripting language for creating advanced PBot factoids
+# and interacting with various internal PBot APIs.
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package Plugins::Plang;
+use parent 'Plugins::Plugin';
+
+use warnings; use strict;
+use feature 'unicode_strings';
+
+use Getopt::Long qw(GetOptionsFromArray);
+
+sub initialize {
+    my ($self, %conf) = @_;
+
+    my $path = $self->{pbot}->{registry}->get_value('general', 'plang_dir') // 'Plang';
+    unshift @INC, $path if not grep { $_ eq $path } @INC;
+    require "$path/Interpreter.pm";
+
+    my $debug = $self->{pbot}->{registry}->get_value('plang', 'debug') // 0;
+    $self->{plang} = Plang::Interpreter->new(embedded => 1, debug => $debug);
+
+    $self->{pbot}->{commands}->register(sub { $self->cmd_plang(@_) }, "plang", 0);
+}
+
+sub unload {
+    my $self = shift;
+    $self->{pbot}->{commands}->unregister("plang");
+}
+
+sub cmd_plang {
+    my ($self, $context) = @_;
+
+    my $usage = "plang <Plang code>; see https://github.com/pragma-/Plang";
+
+    my $getopt_error;
+    local $SIG{__WARN__} = sub {
+        $getopt_error = shift;
+        chomp $getopt_error;
+    };
+
+    my ($show_usage);
+    my @opt_args = $self->{pbot}->{interpreter}->split_line($context->{arguments}, strip_quotes => 1);
+
+    Getopt::Long::Configure("bundling");
+    GetOptionsFromArray(
+        \@opt_args,
+        'h'   => \$show_usage
+    );
+
+    return $usage                         if $show_usage;
+    return "/say $getopt_error -- $usage" if defined $getopt_error;
+    $context->{arguments} = "@opt_args";
+
+    my $result = $self->{plang}->interpret_string($context->{arguments});
+    return "No output." if not defined $result;
+    return "/say $result";
+}
+
+1;