module Ransack::Configuration

def add_predicate(name, opts = {})
  name = name.to_s
  opts[:name] = name
  compounds = opts.delete(:compounds)
  compounds = true if compounds.nil?
  opts[:arel_predicate] = opts[:arel_predicate].to_s
  self.predicates[name] = Predicate.new(opts)
  ['_any', '_all'].each do |suffix|
    self.predicates[name + suffix] = Predicate.new(
      opts.merge(
        :name => name + suffix,
        :arel_predicate => opts[:arel_predicate] + suffix,
        :compound => true
      )
    )
  end if compounds
end

def configure
  yield self
end

def predicate_keys
  predicates.keys.sort {|a,b| b.length <=> a.length}
end