submit-social-housing-lettings-and-sales-data/app/models/form.rb

class Form
  attr_reader :form_definition

  def initialize(form_path)
    raise "No form definition file exists for given year".freeze unless File.exist?(form_path)

    @form_definition = JSON.parse(File.open(form_path).read)
  end

  # Returns a hash with sections as keys
  def all_sections
    @all_sections ||= @form_definition["sections"]
  end

  # Returns a hash with subsections as keys
  def all_subsections
    @all_subsections ||= all_sections.map { |_section_key, section_value|
      section_value["subsections"]
    }.reduce(:merge)
  end

  # Returns a hash with pages as keys
  def all_pages
    @all_pages ||= all_subsections.map { |_subsection_key, subsection_value|
      subsection_value["pages"]
    }.reduce(:merge)
  end

  # Returns a hash with the pages of a subsection as keys
  def pages_for_subsection(subsection)
    all_subsections[subsection]["pages"]
  end

  # Returns a hash with the questions as keys
  def questions_for_page(page)
    all_pages[page]["questions"]
  end

  # Returns a hash with the questions as keys
  def questions_for_subsection(subsection)
    pages_for_subsection(subsection).map { |title, _value| questions_for_page(title) }.reduce(:merge)
  end

  # Returns a hash with soft validation questions as keys
  def soft_validations_for_page(page)
    all_pages[page]["soft_validations"]
  end

  def expected_responses_for_page(page)
    questions_for_page(page).merge(soft_validations_for_page(page) || {})
  end

  def first_page_for_subsection(subsection)
    pages_for_subsection(subsection).keys.first
  end

  def subsection_for_page(page)
    all_subsections.find { |_subsection_key, subsection_value|
      subsection_value["pages"].key?(page)
    }.first
  end

  def next_page(previous_page)
    if all_pages[previous_page].key?("default_next_page")
      next_page = all_pages[previous_page]["default_next_page"]
      return :check_answers if next_page == "check_answers"

      return next_page
    end

    subsection = subsection_for_page(previous_page)
    previous_page_idx = pages_for_subsection(subsection).keys.index(previous_page)
    pages_for_subsection(subsection).keys[previous_page_idx + 1] || :check_answers
  end

  def next_page_redirect_path(previous_page)
    next_page = next_page(previous_page)
    if next_page == :check_answers
      subsection = subsection_for_page(previous_page)
      "case_log_#{subsection}_check_answers_path"
    else
      "case_log_#{next_page}_path"
    end
  end

  def previous_page(current_page)
    subsection = subsection_for_page(current_page)
    current_page_idx = pages_for_subsection(subsection).keys.index(current_page)
    return unless current_page_idx.positive?

    pages_for_subsection(subsection).keys[current_page_idx - 1]
  end

  def all_questions
    @all_questions ||= all_pages.map { |_page_key, page_value|
      page_value["questions"]
    }.reduce(:merge)
  end

  def filter_conditional_questions(questions, case_log)
    applicable_questions = questions

    questions.each do |k, question|
      question.fetch("conditional_for", []).each do |conditional_question_key, condition|
        if condition_not_met(case_log, k, question, condition)
          applicable_questions = applicable_questions.reject { |z| z == conditional_question_key }
        end
      end
    end
    applicable_questions
  end

  def condition_not_met(case_log, question_key, question, condition)
    case question["type"]
    when "numeric"
      operator = condition[/[<>=]+/].to_sym
      operand = condition[/\d+/].to_i
      case_log[question_key].blank? || !case_log[question_key].send(operator, operand)
    when "text"
      case_log[question_key].blank? || !condition.include?(case_log[question_key])
    when "radio"
      case_log[question_key].blank? || !condition.include?(case_log[question_key])
    when "select"
      case_log[question_key].blank? || !condition.include?(case_log[question_key])
    else
      raise "Not implemented yet"
    end
  end

  def get_answer_label(case_log, question_title)
    question = all_questions[question_title]
    if question["type"] == "checkbox"
      answer = []
      question["answer_options"].each { |key, value| case_log[key] == "Yes" ? answer << value : nil }
      return answer.join(", ")
    end

    case_log[question_title]
  end
end