init.el

;;; init.el --- Init file  -*- lexical-binding: t -*-

;; Copyright © 2012–2021 Alex Kost

;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;;
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with this program.  If not, see <http://www.gnu.org/licenses/>.

;; Hacks to reduce the startup time:
;; <https://www.reddit.com/r/emacs/comments/3kqt6e/2_easy_little_known_steps_to_speed_up_emacs_start/>
;; <https://bling.github.io/blog/2016/01/18/why-are-you-changing-gc-cons-threshold/>
(setq gc-cons-threshold (expt 2 24) ; 16 MiB
      garbage-collection-messages t)
(setq load-prefer-newer t)


;;; Location of various files

(defmacro al/file-accessors (name val)
  "Define variable and function for accessing my directories."
  (let ((dir-var  (intern (concat "al/" name "-dir")))
        (file-fun (intern (concat "al/" name "-dir-file"))))
    `(progn
       (defvar ,dir-var ,val)
       (defun ,file-fun (file)
         ,(format "Return full file name of a FILE placed in `%s'."
                  dir-var)
         (expand-file-name file ,dir-var)))))

(al/file-accessors "emacs-init"
                    (file-name-directory
                     (file-truename load-file-name)))
(al/file-accessors "emacs"         (al/emacs-init-dir-file "../"))
(al/file-accessors "emacs-data"    (al/emacs-dir-file "data"))
(al/file-accessors "emacs-utils"   (al/emacs-dir-file "utils"))
(al/file-accessors "emacs-my-packages" (al/emacs-dir-file "packages"))
(al/file-accessors "gnus"          (al/emacs-data-dir-file "gnus"))
(al/file-accessors "gnus-news"     (al/gnus-dir-file "news"))
(al/file-accessors "gnus-mail"     (al/gnus-dir-file "mail"))
(al/file-accessors "gnus-saved"    (al/gnus-dir-file "saved"))

(al/file-accessors "config"        "~/config")
(al/file-accessors "notes"         "~/notes")
(al/file-accessors "progs"         "~/progs")
(al/file-accessors "journal"       (al/notes-dir-file  "journal"))
(al/file-accessors "music"         "~/music")
(al/file-accessors "sound"         "~/docs/audio/small")
(al/file-accessors "tmp"           "~/tmp")
(al/file-accessors "src"           "~/src")
(al/file-accessors "devel"         "~/devel")
(al/file-accessors "download"      "~/downloads")
(al/file-accessors "math"          "~/maths")
(al/file-accessors "echo-download" (al/download-dir-file "echo"))


;;; Guix stuff

(al/file-accessors "guix-profile" "~/.guix-profiles")
(al/file-accessors "guix-system-profile" "/run/current-system/profile")

(defvar al/guix-system?
  (file-exists-p al/guix-system-profile-dir)
  "Non-nil, if current OS is GuixSD.")

(defvar al/guix-profile-names
  '("emacs" "fonts" "games" "build" "guile" "misc" "main"))

(defun al/guix-profile (name)
  "Return file name of my guix profile with NAME."
  (al/guix-profile-dir-file (concat name "/" name)))

(defun al/guix-profiles ()
  "Return a list of all my guix profiles."
  (mapcar #'al/guix-profile al/guix-profile-names))

(al/file-accessors "guix-user-profile" (al/guix-profile "main"))


;;; (Auto)loading various files

(defvar al/pure-config? (getenv "EMPURE")
  "Non-nil, if external packages should not be loaded.")

(setq
 package-user-dir (al/emacs-data-dir-file "elpa")
 package-enable-at-startup nil)

(push al/emacs-utils-dir load-path)

(let (file-name-handler-alist)
  ;; Loading my utils required for the rest config.
  (require 'al-autoload)
  (require 'al-file)
  (require 'al-misc)
  (require 'al-text)

  ;; Autoloading my utils.
  (let ((auto-file (al/autoloads-file al/emacs-utils-dir)))
    (unless (file-exists-p auto-file)
      (with-demoted-errors "ERROR during generating utils autoloads: %S"
        (al/update-autoloads al/emacs-utils-dir)))
    (al/load auto-file))

  ;; Autoloading external packages.
  (unless al/pure-config?
    (with-demoted-errors "ERROR during autoloading ELPA packages: %S"
      (when (require 'al-package nil t)
        (setq
         al/ignored-packages
         '( ;; Installed via Guix:
           pdf-tools
           bui
           dash
           emms
           geiser
           magit
           ;; Redundant dependencies of magit:
           magit-popup git-commit with-editor))

        (advice-add 'package-installed-p
          :around #'al/package-installed-p)
        (advice-add 'quelpa-package-install
          :around #'al/quelpa-package-install)
        (advice-add 'package-compute-transaction
          :around #'al/package-compute-transaction)
        (advice-add 'package-activate-1
          :around #'al/package-activate-1))
      (package-initialize))
    (with-demoted-errors "ERROR during autoloading Guix packages: %S"
      (when (require 'al-guix-autoload nil t)
        (apply #'al/guix-autoload-emacs-packages
               (al/guix-profiles))))
    (when (file-exists-p al/emacs-my-packages-dir)
      (with-demoted-errors "ERROR during autoloading my packages: %S"
        (dolist (dir (al/subdirs al/emacs-my-packages-dir))
          (let* ((elisp-dir (expand-file-name "elisp" dir))
                 (dir (if (file-exists-p elisp-dir)
                          elisp-dir
                        dir)))
            (push dir load-path)
            (mapc #'al/load (al/find-autoloads dir)))))))

  (with-demoted-errors "ERROR during server start: %S"
    (require 'al-server)
    (al/server-named-start "server-emms" "server"))

  ;; Code for optional dependencies on external packages.
  (al/define-package-exists hydra defhydra)
  (al/define-package-exists mwim mwim-beginning)

  (defun al/init-load (file)
    "Load FILE from `al/emacs-init-dir'."
    (al/load (al/emacs-init-dir-file file)))

  ;; Loading the rest config files.
  (mapc #'al/init-load
        '("keys"
          "text"
          "packages"
          "settings"
          "files"
          "prog"
          "time"
          "file-modes"
          "mmedia"
          "net"
          "dict"
          "visual"
          "games"
          "custom")))

(setq custom-file (al/emacs-init-dir-file "custom.el"))

(message "Garbage collected %d times." gcs-done)

;;; init.el ends here