class ConditionForm
  include ActiveModel::Model
  include Logic

  attr_accessor :top_operator_name, :rows

  def to_condition
    case sub_conditions.count
    when 0
      nil
    when 1
      sub_conditions.first
    else
      top_operator_class.new(sub_conditions)
    end
  end

  def delete_row(i)
    rows.slice!(i)

    self
  end

  def change_champ(i)
    sub_conditions[i] = Logic.ensure_compatibility_from_left(sub_conditions[i])

    self
  end

  private

  def top_operator_class
    Logic.class_from_name(top_operator_name)
  end

  def sub_conditions
    @sub_conditions ||= rows.map { |row| row_to_condition(row) }
  end

  def row_to_condition(row)
    left = Logic.from_json(row[:targeted_champ])
    right = parse_value(row[:value])

    Logic.class_from_name(row[:operator_name]).new(left, right)
  end

  def parse_value(value)
    return empty if value.blank?

    number = Integer(value) rescue nil
    return constant(number) if number.present?

    json = JSON.parse(value) rescue nil
    return Logic.from_json(value) if json.present?

    constant(value)
  end
end