;;; lisp/lib/system.el -*- lexical-binding: t; -*-

;;;###autoload
(defun doom-system-distro ()
  "Return a symbol representing the installed distro."
  ;; REVIEW Use `with-memoization' when 27.x support is dropped
  (or (get 'doom-system-distro 'cached-value)
      (put 'doom-system-distro 'cached-value
           (cond ((featurep :os 'windows) 'windows)
                 ((featurep :os 'macos)   'macos)
                 ((and (file-exists-p "/etc/os-release")
                       (with-temp-buffer
                         (insert-file-contents "/etc/os-release")
                         (when (re-search-forward "^ID=\"?\\([^\"\n]+\\)\"?" nil t)
                           (intern (downcase (match-string 1)))))))
                 ;; A few redundancies in case os-release fails us
                 ((file-exists-p "/etc/debian_version")
                  'debian)
                 ((executable-find "nixos-version")
                  'nixos)
                 ((and (or (file-exists-p "/etc/config.scm")
                           (file-directory-p "/run/current-system"))
                       (executable-find "guix"))
                  'guix)
                 ('linux)))))

;;;###autoload
(defun doom-system-distro-version ()
  "Return a distro name and version string."
  (letf! (defun sh (&rest args) (cdr (apply #'doom-call-process args)))
    (let ((distro (doom-system-distro)))
      (cond
       ((eq distro 'windows)
        (format "Windows %s" "Unknown")) ; TODO
       ((eq distro 'macos)
        (format "MacOS %s" (sh "sw_vers" "-productVersion")))
       ((executable-find "lsb_release")
        (sh "lsb_release" "-s" "-d"))
       ((executable-find "nixos-version")
        (format "NixOS %s" (sh "nixos-version")))
       ((and (file-exists-p "/etc/os-release")
             (with-temp-buffer
               (insert-file-contents "/etc/os-release")
               (when (re-search-forward "^PRETTY_NAME=\"?\\([^\"\n]+\\)\"?" nil t)
                 (match-string 1)))))
       ((when-let (files (doom-glob "/etc/*-release"))
          (truncate-string-to-width
           (replace-regexp-in-string "\n" " " (cat (car files) 73) nil t)
           64 nil nil "...")))
       ((concat "Unknown " (sh "uname" "-v")))))))

;;;###autoload
(defun doom-system-distro-icon ()
  "Display icon for the installed distro."
  ;; REVIEW Use `with-memoization' when 27.x support is dropped
  (or (get 'doom-system-distro-icon 'cached-value)
      (put 'doom-system-distro-icon 'cached-value
           (propertize
            (pcase (doom-system-distro)
              (`windows (all-the-icons-faicon "windows"))
              (`macos (all-the-icons-faicon "apple"))
              (`arch "\uF303")
              (`debian "\uF306")
              (`raspbian "\uF315")
              (`ubuntu "\uF31b")
              (`elementary "\uF309")
              (`fedora "\uF30a")
              (`coreos "\uF305")
              (`gentoo "\uF30d")
              (`mageia "\uF310")
              (`centos "\uF304")
              ((or `opensuse `tumbleweed) "\uF314")
              (`sabayon "\uF317")
              (`slackware "\uF319")
              (`linuxmint "\uF30e")
              (`alpine "\uF300")
              (`aosc "\uF301")
              (`nixos "\uF313")
              (`devuan "\uF307")
              (`manjaro "\uF312")
              ((or `void `artix) "\uF17c")
              (_ (all-the-icons-faicon "linux")))
            'face '(:height 1)
            'display '(raise 0)))))

;;;###autoload
(defun doom-system-cpus ()
  "Return the max number of processing units on this system.
Tries to be portable. Returns 1 if cannot be determined."
  (or (get 'doom-system-cpus 'cached-value)
      (put 'doom-system-cpus 'cached-value
           (let ((cpus
                  (cond ((fboundp 'w32-get-nproc)
                         (w32-get-nproc))
                        ((getenv "NUMBER_OF_PROCESSORS"))
                        ((executable-find "nproc")
                         (doom-call-process "nproc"))
                        ((executable-find "sysctl")
                         (doom-call-process "sysctl" "-n" "hw.ncpu")))))
             (max
              1 (or (cl-typecase cpus
                      (integer cpus)
                      (string
                       (condition-case _
                           (string-to-number cpus)
                         (wrong-type-argument
                          (user-error "NUMBER_OF_PROCESSORS contains an invalid value: %S"
                                      cpus))))
                      (cons
                       (if (zerop (car cpus))
                           (string-to-number (cdr cpus))
                         (user-error "Failed to look up number of processors, because:\n\n%s"
                                     (cdr cpus)))))
                    1))))))