#!/usr/bin/perl
use strict;
use warnings FATAL => 'all';
use YAML qw( LoadFile Dump );
use Template;
use B::Keywords;
use Getopt::Long;

GetOptions(
    'debug' => \my $debug,
    'nomake' => \my $do_makefile,
);

$_ = $_ ? 1 : 0 for $debug;
$_ = $_ ? 0 : 1 for $do_makefile;

sub load_fns
{
    my @fns = <fns/*.fn>;
    my %fns;
    for my $file (@fns) {
        warn "$file...\n" if $debug;
        my $data = LoadFile( $file );
        $data->{name} ||= do {
            $file =~ m[/([^.]+)] and $1;
        };
        die "$data->{name} has no docs!" unless length $data->{docs};
        $fns{$data->{name}} = $data;
    }

    return \%fns;
}

sub inject
{
    my ( $data) = @_;
    my %perl = map { ($_,1) } @B::Keywords::Functions;
    my @values = @{$data}{sort keys %$data};

    chomp( my @synopses = grep defined, map { $_->{synopsis} } @values );
    s/^/    /mg for @synopses;
    defined $_->{synopsis} and $_->{synopsis} =~ s/^/    /mg for @values;
    my %requirements = map { %$_ } grep defined, map { $_->{requirements} } @values;

    my @autoinstall;
    for ( @values )
    {
        next unless $_->{requirements};
        push @autoinstall, {
            name => $_->{name},
            requirements => $_->{requirements},
        };
    }

    for ( values %$data ) {
        $_->{exports} ||= [ $_->{name} ];
        delete $_->{exports} if exists $perl{$_->{name}};
        $_->{badegg} = !$_->{code} && $_->{exports};
    }
    my $injection = {
        autoinstall => \@autoinstall,
        synopses => \@synopses,
        requirements => \%requirements,
        fns => $data,
    };

    my $tt = Template->new() or die $Template::ERROR;
    return sub {
        my ($in, $out) = @_;
        warn "Formatting $in...\n";
        $tt->process( $in, $injection, $out ) or die $tt->error();
    };
}

{
    my $fns = load_fns();
    my $formatter = inject( $fns );
    $formatter->( 'Strings.tt', 'Strings.pm' );
    $formatter->( 'Makefile.tt', 'Makefile.PL' ) if $do_makefile;
}