#!/usr/bin/env perl

use warnings;
use strict;
use feature 'say';

use File::Path qw(make_path);
use PPI;

if (! @ARGV) {
    say "USAGE: ./syntax_check perl_script.pl";
    exit;
}

my $file = $ARGV[0];
die "Can't open file '$file': $!" if ! -f $file;

my $lib_dir = 'test_lib/';

if (! -d $lib_dir) {
    mkdir $lib_dir or die $!;
}

my $doc = PPI::Document->new($file);

my $includes = $doc->find('PPI::Statement::Include');

for my $include (@$includes) {

    my $module = $include->module;
    my $package = $module;

    # Skip pragmas

    if ($module eq lc $module) {
        say "Skipping assumed pragma '$module'";
        next;
    }

    $module =~ s|::|/|g;

    if (my ($dir, $file) = $module =~ m|^(.*)/(.*)$|) {
        $file .= '.pm';
        my $path = "$dir/$file";

        # Skip includes that are actually available
        
        if (exists $INC{$path}) {
            say "Skipping available module '$package'";
            next;
        }
      
        if (! -d "$lib_dir/$dir") { 
            make_path("$lib_dir/$dir") or die $!;
        }

        if (! -f "$lib_dir/$path") {
            open my $wfh, '>', "$lib_dir/$path" or die $!;
            print $wfh '1;';
            close $wfh or die $!;
        }
    }
}

say '';

`perl -I$lib_dir -c $file`;