require Cwd;
require Pod::Html;
require Config;
use File::Spec::Functions ':ALL';
use File::Path 'remove_tree';
use File::Copy;

# make_test_dir and rem_test_dir dynamically create and remove testdir/test.lib.
# it is created dynamically to pass t/filenames.t, which does not allow '.'s in
# filenames as '.' is the directory separator on VMS. All tests that require
# testdir/test.lib to be present are skipped if test.lib cannot be created.
sub make_test_dir {
    if (-d 'testdir/test.lib') {
        warn "Directory 'test.lib' exists (it shouldn't yet) - removing it";
        rem_test_dir();
    }
    mkdir('testdir/test.lib') or return "Could not make test.lib directory: $!\n";
    copy('testdir/perlpodspec-copy.pod', 'testdir/test.lib/podspec-copy.pod')
        or return "Could not copy perlpodspec-copy: $!";
    copy('testdir/perlvar-copy.pod', 'testdir/test.lib/var-copy.pod')
        or return "Could not copy perlvar-copy: $!";
    return 0;
}

sub rem_test_dir {
    return unless -d 'testdir/test.lib';
    remove_tree('testdir/test.lib')
        or warn "Error removing temporary directory 'testdir/test.lib'";
}

sub convert_n_test {
    my($podfile, $testname, @p2h_args) = @_;

    my $cwd = Pod::Html::_unixify( Cwd::cwd() );
    my ($vol, $dir) = splitpath($cwd, 1);
    my @dirs = splitdir($dir);
    shift @dirs if $dirs[0] eq '';
    my $relcwd = join '/', @dirs;

    my $new_dir  = catdir $dir, "t";
    my $infile   = catpath $vol, $new_dir, "$podfile.pod";
    my $outfile  = catpath $vol, $new_dir, "$podfile.html";

    # To add/modify args to p2h, use @p2h_args
    Pod::Html::pod2html(
        "--infile=$infile",
        "--outfile=$outfile",
        "--podpath=t",
        "--htmlroot=/",
        "--podroot=$cwd",
        @p2h_args,
    );

    $cwd =~ s|\/$||;

    my ($expect, $result);
    {
	local $/;
	# expected
	$expect = <DATA>;
	$expect =~ s/\[PERLADMIN\]/$Config::Config{perladmin}/;
	$expect =~ s/\[RELCURRENTWORKINGDIRECTORY\]/$relcwd/g;
	$expect =~ s/\[ABSCURRENTWORKINGDIRECTORY\]/$cwd/g;
	if (ord("A") == 193) { # EBCDIC.
	    $expect =~ s/item_mat_3c_21_3e/item_mat_4c_5a_6e/;
	}
    if (Pod::Simple->VERSION > 3.28) {
        $expect =~ s/\n\n(some html)/$1/m;
        $expect =~ s{(TESTING FOR AND BEGIN</h1>)\n\n}{$1}m;
    }

	# result
	open my $in, '<', $outfile or die "cannot open $outfile: $!";
	$result = <$in>;
	close $in;
    }

    my $diff = '/bin/diff';
    -x $diff or $diff = '/usr/bin/diff';
    -x $diff or $diff = undef;
    my $diffopt = $diff ? $^O =~ m/(linux|darwin)/ ? '-u' : '-c'
                        : '';
    $diff = 'fc/n' if $^O =~ /^MSWin/;
    $diff = 'differences' if $^O eq 'VMS';
    if ($diff) {
	ok($expect eq $result, $testname) or do {
	  my $expectfile = "${podfile}_expected.tmp";
	  open my $tmpfile, ">", $expectfile or die $!;
	  print $tmpfile $expect;
	  close $tmpfile;
	  open my $diff_fh, "-|", "$diff $diffopt $expectfile $outfile" or die $!;
	  print STDERR "# $_" while <$diff_fh>;
	  close $diff_fh;
	  unlink $expectfile;
	};
    } else {
	# This is fairly evil, but lets us get detailed failure modes
	# anywhere that we've failed to identify a diff program.
	is($expect, $result, $testname);
    }

    # pod2html creates these
    1 while unlink $outfile;
    1 while unlink "pod2htmd.tmp";
}

1;