#
# Shortens GitHub URLs.
#
# Authors:
#   Joel Kuzmarski <leoj3n@gmail.com>
#   Sorin Ionescu <sorin.ionescu@gmail.com>
#

local url="$1"

if [[ -z "$url" ]]; then
  print "usage: $0 [ url | - ] [slug]" >&2
  return 1
elif [[ "$url" == '-' ]]; then
  read url <&0
elif [[ "$url" != *github.com* ]]; then
  url="https://github.com/$url"
fi

if (( $+commands[curl] )); then
  local result="$(curl -s -i 'http://git.io' -F "url=$url" -F "code=$2")"

  if [[ $result == *Unprocessable* ]]; then
    print "$0: the slug '$2' is already taken!" >&2
  else
    print $result | grep 'Location:' | sed 's/Location: //'
  fi
else
  print "$0: command not found: curl" >&2
fi