require 'sqreen/rules/attrs'
require 'sqreen/rules/rule_cb'

module Sqreen
  module Rules
    class NotFoundCB < RuleCB
      IGNORED_EXTENSIONS = ['.css', '.gif', '.jpg', '.jpeg', '.png', '.svg', '.ico', '.webp', '.pdf', '.woff'].freeze

      def post(rv, _inst, args, _budget = nil, &_block)
        return if rv[0].to_i != 404

        env         = args[0]
        ua          = env['HTTP_USER_AGENT']
        script_name = env['SCRIPT_NAME']
        path_info   = env['PATH_INFO']
        verb        = env['REQUEST_METHOD']
        host        = env['SERVER_NAME']
        override    = env['action_dispatch.original_path']
        exception   = env['action_dispatch.exception']

        record_from_env(ua, script_name, path_info, verb, override, host, exception)
      end

      def record_from_env(ua, script_name, path_info, verb, override, host, exception)
        path = path_from_variables(script_name, path_info, override)

        return if extension?(path, IGNORED_EXTENSIONS)

        if !override && exception && !exception.to_s.empty?
          record_from_exception({ 'ua' => ua, 'verb' => verb, 'host' => host, 'script_name' => script_name, 'path_info' => path_info }, exception.exception)
        end

        record_event({ 'path' => path, 'ua' => ua, 'verb' => verb, 'host' => host })
      end

      def record_from_exception(payload, exception)
        message = exception.to_s

        if message && !message.empty?
          override = message =~ /No route matches\s+\[[a-z]+\]\s+"(.*)"/i && $1
        end
        payload['path'] = path_from_variables(payload['script_name'], payload['path_info'], override)
        return if extension?(payload['path'], IGNORED_EXTENSIONS)

        record = payload.reject { |k, v| v.nil? || ['path_info', 'script_name'].include?(k) }
        payload.delete('path') # remove added claim

        record_event(record)
      end

      def path_from_variables(script_name, path_info, override)
        path = script_name

        if path.nil?
          path = override || path_info
        elsif override
          path += override
        elsif path_info
          path += path_info
        end

        path
      end

      def extension?(path, extensions)
        return false if path.nil?

        candidate = File.extname(path).downcase

        extensions.include?(candidate)
      end
    end
  end
end