#!/usr/bin/env raku

use v6;

=begin pod

=head1 NAME

p6-module-snapshot - create a distribution to reinstall installed modules

=head1 SYNOPSIS

=begin code

    p6-module-snapshot [--directory=<.>]

=end code

=head1 DESCRIPTION

This provides a simple mechanism to take a snapshot of the installed
modules for your rakudo installation as a distribution with
no installables just dependencies.

The data is collected as a META6.json in a timestamped sub-directory
of the current directory (or the directory specified on the command
line,) and you can at some later point change directory into that
directory and do

     panda install .

or

     zef install .

And the modules will be installed. You can of course copy the directory
to another machine or back it up or something.

This can be useful in two separate scenarios - firstly that you need to
do a completely fresh or side-by-side Raku installation on your
system, or you need to duplicate the installed modules from one
system on another.

=end pod

use App::ModuleSnap;
use META6;

multi sub MAIN(Str :$directory = '.') {

    my @parts = 'Snapshot', 'Auto', DateTime.now.Str.subst(/<[:+.-]>/,"", :g);
    my $name = @parts.join('::');
    my $dir-name = @parts.join('-');

    my $dir = $directory.IO.child($dir-name);

    my META6 $meta = App::ModuleSnap.get-meta(:$name);

    if !$dir.d {
        $dir.mkdir;
    }

    $dir.add('META6.json').spurt($meta.to-json);
    say "the snapshot has been written in the directory $dir";
}
# vim: expandtab shiftwidth=4 ft=raku