cybernetlab/ensure_it

#
module EnsureIt
  patch Object do
    def ensure_array(*args, default: [], make: false, **opts)
      return default if make != true
      EnsureIt.ensure_array([self], *args, **opts)
    end

    def ensure_array!(*args, make: false, **opts)
      return EnsureIt.ensure_array([self], *args, **opts) if make == true
      EnsureIt.raise_error(:ensure_array!,
                           **EnsureIt.ensure_array_error(**opts))
    end
  end

  patch NilClass do
    def ensure_array(*args, default: [], make: false, **opts)
      make == true ? [] : default
    end

    def ensure_array!(*args, make: false, **opts)
      return [] if make == true
      EnsureIt.raise_error(:ensure_array!,
                           **EnsureIt.ensure_array_error(**opts))
    end
  end

  patch Array do
    using EnsureIt if ENSURE_IT_REFINED

    def ensure_array(*args, **opts)
      EnsureIt.ensure_array(self, *args, **opts)
    end
    alias_method :ensure_array!, :ensure_array
  end

  ENSURES = %i(ensure_symbol ensure_symbol! ensure_string ensure_string!
               ensure_integer ensure_integer! ensure_float ensure_float!
               ensure_array ensure_array! ensure_class ensure_class!)

  OPERATIONS = %i(compact flatten reverse rotate shuffle sort sort_desc uniq)

  if ENSURE_IT_REFINED
    using EnsureIt

    def self.ensure_array(arr, *args, values: nil, **opts)
      args.each do |arg|
        if arg.is_a?(Proc)
          arr = arr.map(arg)
          next
        end
        arg = arg.ensure_symbol || next
        case arg
        when *ENSURES
          arr =
            case arg
            when :ensure_symbol then arr.map { |x| x.ensure_symbol }
            when :ensure_symbol! then arr.map { |x| x.ensure_symbol! }
            when :ensure_string then arr.map { |x| x.ensure_string }
            when :ensure_string! then arr.map { |x| x.ensure_string! }
            when :ensure_integer then arr.map { |x| x.ensure_integer }
            when :ensure_integer! then arr.map { |x| x.ensure_integer! }
            when :ensure_float then arr.map { |x| x.ensure_float }
            when :ensure_float! then arr.map { |x| x.ensure_float! }
            when :ensure_array then arr.map { |x| x.ensure_array }
            when :ensure_array! then arr.map { |x| x.ensure_array! }
            when :ensure_class then arr.map { |x| x.ensure_class }
            when :ensure_class! then arr.map { |x| x.ensure_class! }
            end
        when *OPERATIONS
          op = arg == :sort_desc ? :sort : arg
          arr = arr.send(op)
          arr = arr.reverse if arg == :sort_desc
        else
          arr = arr.map { |x| x.respond_to?(arg) ? x.send(arg) : nil }
        end
      end
      values.is_a?(Array) ? arr & values : arr
    end
  else
    def self.ensure_array(arr, *args, values: nil, **opts)
      args.each do |arg|
        if arg.is_a?(Proc)
          arr = arr.map(arg)
          next
        end
        arg = arg.ensure_symbol || next
        case arg
        when *ENSURES then arr = arr.map(&arg)
        when *OPERATIONS
          op = arg == :sort_desc ? :sort : arg
          arr = arr.send(op)
          arr = arr.reverse if arg == :sort_desc
        else
          arr = arr.map { |x| x.respond_to?(arg) ? x.send(arg) : nil }
        end
      end
      values.is_a?(Array) ? arr & values : arr
    end
  end

  def self.ensure_array_error(**opts)
    opts[:message] ||= '#{subject} should be an Array'
    opts
  end
end