module PublicExceptionExtension

# File lib/public_exception_extension.rb, line 6
def call(env)
  request = ActionDispatch::Request.new(env)
  status  = request.path_info[1..-1].to_i

  begin
    content_type = request.formats.first
  rescue Mime::Type::InvalidMimeType
    content_type = Mime[:text]
  end

  body = { status: status, error: Rack::Utils::HTTP_STATUS_CODES.fetch(status, Rack::Utils::HTTP_STATUS_CODES[500]) }

  render(request, status, content_type, body)
end

# File lib/public_exception_extension.rb, line 23
def render(request, status, content_type, body)
  format = "to_#{content_type.to_sym}" if content_type

  if format && body.respond_to?(format)
    render_format(status, content_type, body.public_send(format))
  else
    render_html(request, status)
  end
end

# File lib/public_exception_extension.rb, line 33
def render_format(status, content_type, body)
  [
    status,
    {
      "Content-Type" => "#{content_type}; charset=#{ActionDispatch::Response.default_charset}",
      "Content-Length" => body.bytesize.to_s,
    },
    [body],
  ]
end

# File lib/public_exception_extension.rb, line 44
def render_html(request, status)
  if Rails.application.config.respond_to?(:public_exception_template)
    file_path = Rails.application.config.public_exception_template.call(request, status)
    path = File.join(public_path, file_path) if file_path
  end

  path ||= ''

  path = "#{public_path}/#{status}.#{I18n.locale}.html" unless (found = File.exist?(path))
  path = "#{public_path}/#{status}.html" unless (found = File.exist?(path))

  if found || File.exist?(path)
    render_format(status, "text/html", File.read(path))
  else
    [404, { "X-Cascade" => "pass" }, []]
  end
end