#compdef -condition-

local prev="$words[CURRENT-1]"

if [[ "$prev" = -o ]]; then
  _tags -C -o options && _options
elif [[ "$prev" = -([no]t|ef) ]]; then
  _tags -C "$prev" files && _files
else
  _alternative 'files:: _files' 'parameters:: _parameters'
fi
