#!/bin/sh
#|-*- mode:lisp -*-|#
#|
exec ros -Q -- $0 "$@"
|#
(progn ;;init forms
  (ros:ensure-asdf)
  #+quicklisp(ql:quickload '() :silent t)
  )

(defpackage :ros.script.package-updates-exporter.3936516038
  (:use :cl))
(in-package :ros.script.package-updates-exporter.3936516038)

(defun get-distribution ()
  (with-open-file (in "/etc/os-release" :direction :input)
    (let ((os-names '("debian" "alpine" "arch"))
          (found nil))
      (loop for line = (read-line in nil) while line do
        (loop for os in os-names
              when (search os (string-downcase line))
		do (setf found os)))
      found)))

(defun get-package-manager (distro)
  (let ((package-managers '(("debian" . "apt") ("alpine" . "apk") ("arch" . "pacman"))))
    (cdr (assoc distro package-managers :test #'string=))))

(defvar *distribution* (get-distribution))
(defvar *package-manager* (get-package-manager *distribution*))


(defun get-upgradable (package-manager)
  (let ((package-managers '(("apt" . "list --upgradable | grep \"upgradable\"")
                            ("apk" . "list --upgradable")
                            ("pacman" . "-Qu"))))
    (let ((command (assoc package-manager package-managers :test #'string=)))
      (if command
          (count #\Newline (or (uiop:run-program `(,package-manager ,(cdr command)) :output :string :ignore-error-status t) ""))
          (error "Unknown package manager: ~A" package-manager)))))

(defun main (&rest argv)
  (let* ((architecture (uiop:run-program '("uname" "-m") :output :string))
         (upgradable (get-upgradable *package-manager*)))
    (format t "# HELP ~a_upgrades_pending Packages pending updates by origin~%" *package-manager*)
    (format t "# TYPE ~a_upgrades_pending gauge~%" *package-manager*)
    (format t "~a_package_pending_update{arch=\"~a\"} ~d~%" *package-manager* (string-trim '(#\Newline) architecture) upgradable)))

;;; vim: set ft=lisp lisp: