#!/usr/bin/env bash
# Abstract calls to Bash help vs man(1)
self=han

# Give up completely if no BASH_VERSINFO (<2.0)
if ! [ -n "$BASH_VERSINFO" ] ; then
    exit
fi

# Figure out the options with which we can call help; Bash >=4.0 has an -m
# option which prints the help output in a man-page like format.
declare -a helpopts
if ((BASH_VERSINFO[0] >= 4)) ; then
    helpopts=(-m)
fi

# Create a temporary file and set up a trap to get rid of it.
tmpdir=$(mktemp -dt "$self".XXXXXX) || exit
cleanup() {
    rm -fr -- "$tmpdir"
}
trap cleanup EXIT

# If we have exactly one argument and a call to the help builtin with that
# argument succeeds, display its output with `pager -s`.
if (($# == 1)) &&
   help "${helpopts[@]}" "$1" >"$tmpdir"/"$1".help 2>/dev/null ; then
    (cd -- "$tmpdir" && pager -s -- "$1".help)

# Otherwise, just pass all the arguments to man(1).
else
    man "$@"
fi