#!perl
use Vim::Snippet::Converter;
use Vim::Snippet::Completion;
use File::Basename;
use Getopt::Long;
use File::Path qw(mkpath rmtree);
use File::Copy 'copy';

my ( 
    $opt_src_fn,
    $opt_install_to,
    $opt_help,
    $opt_default_target_dir,
    $opt_completion);

GetOptions(
    'h|help'     => \$opt_help,
    's|src=s'    => \$opt_src_fn,
    'd'          => \$opt_default_target_dir,
    'i|install-to=s' => \$opt_install_to,
    'c|create-completion=s' => \$opt_completion ,
);

if( $opt_help ) {
    print <<'EOF';

Slippery Snippets Converter.

    Usage:

    # generate snippet vim script to stdout
    $ scc -s filename.snt > perl_snippets.vim
    
    # to replace the previous install automatically.
    $ scc -s filename.snt -i ~/.vim/syntax/perl.vim

    -s, --src  [filename]
        specify source file path

    -i, --install-to [filename]
        specify vim script path, e.g.  ~/.vim/syntax/perl.vim

    -c, --create-completion [filepath]
        create snippet keyword completion file for vim

EOF
    exit;
}

die("Please specify source file: -s filename.snt") if ( !defined $opt_src_fn );



my $src_filename = basename( $opt_src_fn );

$scc = new Vim::Snippet::Converter;
my ($in,$out);
open $in,  '<', $opt_src_fn;

if( $opt_install_to ) {
    
# mkpath $opt_install_to;

    # if file exists 
    # find the previous install
    if( -e $opt_install_to ) {
        # remove the previous install

        open my $fh1, "<" , $opt_install_to;
        my @lines = <$fh1>;
        my $i = 0;
        my $idx_start = -1;
        my $idx_end   = -1;
        foreach my $line ( @lines ) {
            $idx_start = $i  if ( $line =~ m{\Q"=====SNIPPET START:$src_filename} );
            $idx_end = $i    if ( $line =~ m{\Q"=====SNIPPET END:$src_filename} );
            $i++;
        }
        close $fh1 ;

        # splice 
        if( $idx_start > -1 ) {
            print STDERR "Found previous install: $idx_start-$idx_end\n";
            splice @lines,$idx_start,$idx_end - $idx_start + 1;

            # write back
            open $fh1 , ">" , $opt_install_to;
            print $fh1 @lines;
            close $fh1;
        }
    }

    # open file descriptor to target
    open $out, '>>', $opt_install_to;
} 
else {
    open $out, '>&', STDOUT;
}

print $out "\"=====SNIPPET START:$src_filename \n";
$scc->convert( $in, $out );
print $out "\"=====SNIPPET END:$src_filename \n";

close( $in, $out );
print STDERR <<END;

Use these settings to beautify your snippet:
------------------------------------------------
        let g:snip_start_tag = "«"
        let g:snip_end_tag = "»"
END


if ($opt_completion) {
    $keywords = $scc->{triggers};
    $comp     = new Vim::Snippet::Completion;
    $comp->gen({   
            output => $opt_completion ,
            list   => $scc->{triggers},
            opt    => 'new',
    });
    
    print STDERR <<EOF;

Vim completion file: $opt_completion 
please move $opt_completion to your home directory 
and append the below setting in your .vimrc

    set dict+=~/$opt_completion

EOF
}

print STDERR "Done";

__END__