#!/usr/bin/env ruby
=begin =======================================================================

# BINMAN 1 2012-10-14 3.2.0

## NAME

binman - man pages for bin scripts

## SYNOPSIS

`binman` [*OPTION*]... *COMMAND*

## DESCRIPTION

[binman] produces UNIX manual pages for your executable scripts. It can
extract their leading comment headers (defined below), convert them from
markdown(7) into roff(7) using [md2man], and display them using man(1).

### Leading comment headers

A leading comment header can be one of the following two things:

1.  A contiguous sequence of single-line comments (which begin with `#`
    and optionally continue with a single space followed by any number of
    characters until the end of the line) starting at the beginning of the
    file (after shebang and encoding comments plus optional blank lines) and
    ending at the first single blank line.

2.  The first embedded document delimited by `=begin` and `=end` lines, which
    begin with the respective delimiters and optionally continue with a single
    space followed by any number of characters until the end of the line.

### Markdown processing divergence

Although your leading comment headers are written in markdown(7), `binman
conv` inherits the following additions to markdown(7) syntax from [md2man]:

  * There can be at most one top-level heading (H1).  It is emitted as `.TH`
    in the roff(7) output to define the UNIX manual page's header and footer.

  * Paragraphs whose lines are all uniformly indented by two spaces are
    considered to be "indented paragraphs".  They are unindented accordingly
    before emission as `.IP` in the roff(7) output.

  * Paragraphs whose subsequent lines (all except the first) are uniformly
    indented by two spaces are considered to be a "tagged paragraphs".  They
    are unindented accordingly before emission as `.TP` in the roff(7) output.

### Markdown processing extensions

The following [Redcarpet] extensions are enabled while processing markdown(7):

  * tables
  * autolink
  * superscript
  * strikethrough
  * no_intra_emphasis
  * fenced_code_blocks

## OPTIONS

`-h`, `--help`
  Show this help manual.

## COMMANDS

`help` *FILE* [*ARGUMENT*]...
  If the given *ARGUMENT* sequence contains `-h` or `--help` except after
  `--`, then this program extracts the given *FILE*'s leading comment header,
  converts it into roff(7), and displays it using man(1) before exiting with
  status code `0`.  Otherwise, this program exits with status code `111`.

`show` [*FILE*]
  Use man(1) to display the roff(7) conversion of the leading comment header
  extracted from the given *FILE* or STDIN.

`load` [*FILE*]
  Print the leading comment header extracted from the given *FILE* or STDIN.

`dump` [*FILE*]
  Print the roff(7) conversion of the leading comment header extracted from
  the given *FILE* or STDIN.

`conv` [*FILE*]
  Print the roff(7) conversion of the markdown(7) document read from the given
  *FILE* or STDIN.

## SEE ALSO

man(1), roff(7), markdown(7)

[binman]: https://github.com/sunaku/binman
[md2man]: https://github.com/sunaku/md2man
[Redcarpet]: https://github.com/vmg/redcarpet

=end =========================================================================

require 'binman'

command, source = ARGV

if command == 'help'
  BinMan.help source, ARGV[2..-1]
  exit 111
else
  BinMan.help
  source ||= STDIN
  case command
  when 'show'
    BinMan.send(command, source)
  when 'load', 'dump', 'conv'
    puts BinMan.send(command, source)
  else
    warn 'binman: invalid command; try --help'
    exit 1
  end
end