module MongoidEnumerable

# File lib/mongoid_enumerable.rb, line 25
def self.define_enumerable_method(model:, field_name:, values:, default:, prefix:, before_change:, after_change:)
  model.field(field_name, type: String, default: default)

  values.each do |value|
    define_value_methods(
      model: model,
      value: value,
      field_name: field_name,
      prefix: prefix,
      before_change: before_change,
      after_change: after_change
    )
  end

  model.define_singleton_method("all_#{field_name}") do
    values
  end
end

# File lib/mongoid_enumerable.rb, line 11
def self.define_enumerable_methods(model)
  model.define_singleton_method :enumerable do |field_name, values, options = {}|
    MongoidEnumerable.define_enumerable_method(
      model: model,
      field_name: String(field_name),
      values: values.collect(&:to_s),
      default: options.fetch(:default, values.first),
      prefix: options.fetch(:prefix, nil),
      before_change: options[:before_change],
      after_change: options[:after_change]
    )
  end
end

# File lib/mongoid_enumerable.rb, line 44
def self.define_value_methods(model:, value:, field_name:, prefix:, before_change:, after_change:)
  method_name = "#{prefix}#{value}"

  model.define_method("#{method_name}!") do
    value_before = send(field_name)
    value_after = value

    callback_result = run_callback(callback_method_name: before_change,
                                   value_before: value_before, value_after: value_after)

    if callback_result
      update!(field_name => value)
      run_callback(callback_method_name: after_change,
                   value_before: value_before, value_after: value_after)
    end
  end

  model.define_method("#{method_name}?") do
    send(field_name) == value
  end

  model.scope method_name, -> { where(field_name => value) }
end

# File lib/mongoid_enumerable.rb, line 7
def self.included(model)
  define_enumerable_methods(model)
end

# File lib/mongoid_enumerable.rb, line 68
def run_callback(callback_method_name:, value_before:, value_after:)
  if callback_method_name
    callback_method = method(callback_method_name)
    validate_callback_method(method: callback_method)

    callback_method.call(value_before, value_after)
  else
    true
  end
end

# File lib/mongoid_enumerable.rb, line 79
def validate_callback_method(method:)
  return if method.arity == 2 || method.arity.negative?

  raise "Method #{method.name} must receive two parameters: old_value and new_value"
end