#!/bin/sh
# Shell script implementing the Aliens interface for luarocks.
# Copyright 2009 Michael Homer. Released under the GNU GPL 2 or later.

getversion() {
   prog="$1"
   luarocks list "$prog" | awk '
      {
         if (found) {
            print $1
            exit
         }
      }
      /^'"$prog"'$/ { found=1 }'
}

in_version_range() {
   lower="$1"
   ver="$2"
   upper="$3"
   [ "$ver" ] || return 1
   [ "$ver" != "$lower" -a "$(GuessLatest "$ver" "$lower")" = "$lower" ] && return 1
   [ "$upper" ] || return 0
   [ "$(GuessLatest "$ver" "$upper")" = "$upper" ] || return 1
   [ "$ver" = "$upper" -a "$ver" != "$lower" ] && return 1
   return 0
}

getinstallversion() {
   prog="$1"
   for V in $(luarocks search "$prog" | awk '
      /^$/ && found { exit }
      found { print $1 }
      /^'"$prog"'$/ { found=1 }') 
   do
      if in_version_range "$2" "$V" "$3"
      then
         echo $V
         return 0
      fi
   done
}

install() {
   prog="$1"
   ver="$2"
   luarocks install "$prog" "$ver"
}

command="$1"
prog="$2"

case "$command" in
   --getversion)
      echo $(getversion "$2")
      ;;
   --getinstallversion)
      echo $(getinstallversion "$2" "$3" "$4")
      ;;
   --greater-than)
      ver=$(getversion "$2")
      latest=$(GuessLatest "$ver" "$3")
      [ "$latest" = "$3" ] && exit 1 || exit 0
      ;;
   --met|--within-range|--interval)
      prog="$2"
      lower="$3"
      upper="$4"
      ver=$(getversion "$2")
	  in_version_range "$lower" "$ver" "$upper"
      ;;
   --have-manager)
      which luarocks >/dev/null 2>&1 || exit 1
      ;;
   --get-manager-rule)
      echo "LuaRocks >= 1.0"
      ;;
   --install)
      install "$2" "$3"
      ;;
esac # is ridiculous