module Formulario
  class Field
    class UnvalidatedField
      attr_accessor :field_name

      attr_accessor :value
      attr_accessor :field_type
      attr_accessor :default
      attr_accessor :validators

      attr_accessor :form

      def initialize(
            field_name: ,

            value:      nil,
            field_type: Field,
            default:    Field.type_for(field_type).default,
            validators: []
          )


        @field_name = field_name

        @field_type = field_type
        @default    = default
        @validators = validators

      end

      def validate(validator=Undefined,
                   message: Undefined, &validation_block)

        validation_function = case
                              when block_given?
                                validation_block
                              when validator.is_a?(Symbol)
                                validator
                              when validator.is_a?(::Formulario::Validator)
                                validator
                              end

        validators << {
          validator: validation_function,
          message:   message,
        }
      end

      def validate!(form)
        self.form = form

        validators.inject(field_type.for(value.value)) do |current_value, validator_hash|
          validator_block = case validator_hash[:validator]
                            when ::Formulario::Validator
                              validator_hash[:validator]
                            when Symbol
                              ::Formulario::Validator.new(&value.method(validator_hash[:validator]))
                            when Proc
                              ::Formulario::Validator.new(&validator_hash[:validator])
                            end

          if instance_exec(value: value.value, object: self, field_name: field_name, &validator_block.to_proc).valid?
            current_value
          else
            message = if validator_hash[:validator].is_a?(::Formulario::Validator)
                        validator_hash[:validator].message
                      end

            value.exceptional_class
              .new(current_value,
                   reasons: message || validator_hash[:message])
          end
        end

      end

    end
  end
end