#! /usr/bin/perl

# filter to implement the old -F (--history-format) option, which was badly implemented and never
# used anyway. The simplicity of this script shows the usefulness of the filter concept. 
# As a bonus, it is much easier to modify than the original rlwrap source code

use lib ($ENV{RLWRAP_FILTERDIR} or ".");
use RlwrapFilter;
use POSIX qw(strftime);
use strict;


my ($raw_input, $prompt);

my $filter = new RlwrapFilter;
my $name = $filter -> name;
my $format = join " ", @ARGV; # you may specify the format without quotes (as in -z 'history_format -- %D') 
my ($prefix) = ($format =~ /^(.*?)\%/);
$prefix ||= $format;




$filter -> help_text("Usage: rlwrap -z '$name <format>' <command>\n".
		     "Append <format> to every history item, and strip it off again when input is accepted\n" .
                     "escape codes in <format> will be replaced: %D by the current working directory,\n" .
                     "%P by the current prompt and %C by the command name, and all the remaining escape codes\n" .
                     "as understood by strftime (3)") ;

$filter -> input_handler(\&strip_off);
$filter -> echo_handler(sub{$raw_input});
$filter -> history_handler(sub {strip_off($_) . " " . expand($format)});
$filter -> prompt_handler(sub{$prompt = $_});
$filter -> run;




sub expand {
  my ($format) = @_;
  my $expanded = POSIX::strftime($format, localtime(time));
  my $pwd = eval {$filter -> cwd};
  $pwd = "?" if $@;
  my $command_name = ($filter -> command_line)[0];
  $expanded =~ s/%P/$prompt/g;
  $expanded =~ s/%C/$command_name/g;
  $expanded =~ s/%D/$pwd/g;
  return $expanded;
}

sub strip_off {
  ($raw_input) = @_;
  my $stripped = $raw_input;
  $stripped =~ s/ ?\Q$prefix\E.*//;
  return $stripped;
}
