ransack_enum_text_search.rb

=begin
Given enum like status: %i(bad good great)
ransacker(:status){ Arel.sql(ites('status')) }
will allow to perform:

Model.search(status_cont: 'a') => returns models with bad and great statuses
Model.search(status_cont: 'g') => returns models with good and great statuses

Another way to solve http://stackoverflow.com/questions/37257835/searching-on-an-enum-field-with-ransack
=end

  # This method is not needed
  def self.enums_to_db
    defined_enums.each do |name, map|
      connection.execute <<~EOF
        CREATE TYPE #{name} AS ENUM ('#{map.keys.join("', '")}');
      EOF
    end
  end

  def self.hash_to_psql_case(field, hash, other = nil)
    hash.reduce("CASE") do |m, kv|
      k, v = kv
      m += " WHEN #{field}=#{v} THEN '#{k}'"
    end +
      (other.present? ? " ELSE '#{other}'" : '') +
      ' END'
  end
  singleton_class.send(:alias_method, :htpc, :hash_to_psql_case)

  def self.int_to_enum_string(field)
    htpc(field, defined_enums[field])
  end
  singleton_class.send(:alias_method, :ites, :int_to_enum_string)

  # ransacker(:attempt_type){ Arel.sql(ites('attempt_type')) }