;;; basics.el --- Super basic Emacs settings -*- lexical-binding: t -*-

;;; Commentary:

;; These are the settings that I literally cannot live without.  Basic
;; settings, built-in packages, that kind of stuff.  Everything else
;; goes in init.el.

;;; Code:

;;; Directories

(defmacro defdir (name directory &optional docstring makedir)
  "Define a variable and a function NAME expanding to DIRECTORY.
DOCSTRING is applied to the variable; its default is DIRECTORY's
path.  If MAKEDIR is non-nil, the directory and its parents will
be created."
  (declare (indent 2) (doc-string 3))
  `(progn
     (defvar ,name (expand-file-name ,directory)
       ,(concat (or docstring (format "%s" directory)) "\n"
                "Defined by `defdir'."))
     (defun ,name (file &optional mkdir)
       ,(concat "Expand FILE relative to variable `" (symbol-name name) "'.\n"
                "If MKDIR is non-nil, parent directories are created.\n"
                "Defined by `defdir'.")
       (let ((file-name (expand-file-name
                         (convert-standard-filename file) ,name)))
         (when mkdir
           (make-directory (file-name-directory file-name) :parents))
         file-name))
     ,(if makedir
	  `(make-directory ,directory :parents)
	`(unless (file-exists-p ,directory)
	   (warn "Directory `%s' doesn't exist." ,directory)))))

(defdir etc/ (locate-user-emacs-file "etc/")
  "Where various Emacs files are placed."
  :makedir)

(defdir lisp/ (locate-user-emacs-file "lisp/")
  "My bespoke elisp files."
  :makedir)
(push lisp/ load-path)

(defdir sync/ "~/Sync/"
  "My Syncthing directory."
  :makedir)

(defdir private/ (sync/ "emacs/private/")
  "Private files and stuff."
  :makedir)
(push private/ load-path)

(use-package no-littering
  :ensure t :demand t
  :preface
  (setq-default no-littering-etc-directory etc/
		no-littering-var-directory etc/))

;;; Settings

;; Async
(setq-default async-shell-command-buffer 'new-buffer
	      async-shell-command-display-buffer nil)

;; Scrolling
(setq-default  auto-hscroll-mode t
	       auto-window-vscroll nil
	       fast-but-imprecise-scrolling t
	       hscroll-margin 1
	       hscroll-step 1
	       scroll-conservatively 25
	       scroll-margin 0
	       scroll-preserve-screen-position 1
	       scroll-step 1)
(scroll-bar-mode -1)
(horizontal-scroll-bar-mode -1)
(pixel-scroll-precision-mode)

;; Cursor
(setq-default cursor-in-non-selected-windows 'hollow
	      cursor-type 'bar
	      blink-cursor-blinks 1
	      blink-cursor-interval 0.25
	      blink-cursor-delay 0.25)
(blink-cursor-mode)

;; Mouse
(setq-default mouse-drag-copy-region t
	      mouse-wheel-progressive-speed nil
	      mouse-yank-at-point t)

;; Dialogs
(unless (boundp 'use-short-answers)
  (fset 'yes-or-no-p 'y-or-n-p))

(setq-default read-answer-short t
	      use-dialog-box nil
	      use-file-dialog nil
	      use-short-answers t)

;; Minibuffer
(setq-default completion-ignore-case t
	      read-buffer-completion-ignore-case t
	      read-file-name-completion-ignore-case t
	      completions-detailed t
	      enable-recursive-minibuffers t
	      file-name-shadow-properties '(invisible t intangible t)
	      minibuffer-eldef-shorten-default t
	      minibuffer-prompt-properties '( read-only t
					      cursor-intangible t
					      face minibuffer-prompt))
(file-name-shadow-mode)
(minibuffer-electric-default-mode)

(require 'savehist)
(setq-default history-length 1024
	      history-delete-duplicates t
	      ;; savehist-file (etc/ "savehist.el")
	      savehist-save-minibuffer-history t
	      savehist-autosave-interval 30)
(savehist-mode)

;; Undo
(setq-default undo-limit (* 10 1024 1024))

;; Killing and yanking
(setq-default kill-do-not-save-duplicates t
	      kill-read-only-ok t
	      save-interprogram-paste-before-kill t
	      yank-pop-change-selection t)
(delete-selection-mode)

;; Notifying the user
(setq-default echo-keystrokes 0.01
	      ring-bell-function #'ignore)

;; Point and mark
(setq-default set-mark-command-repeat-pop t)

;; The system
(setq-default read-process-output-max (* 10 1024 1024))

;; Startup
(setq-default inhibit-startup-screen t
	      initial-buffer-choice t
	      initial-scratch-message nil)

;; (menu-bar-mode -1)
(tool-bar-mode -1)
(tooltip-mode -1)

;; Text editing
(setq-default fill-column 80
	      sentence-end-double-space t
	      tab-width 8)
(global-so-long-mode)

(setq-default show-paren-delay 0.01
	      show-paren-style 'parenthesis
	      show-paren-when-point-in-periphery t
	      show-paren-when-point-inside-paren t)
(show-paren-mode)
(electric-pair-mode)

;; Encodings
(set-language-environment "UTF-8")
(setq-default buffer-file-coding-system 'utf-8-unix
              coding-system-for-read 'utf-8-unix
              coding-system-for-write 'utf-8-unix
              default-process-coding-system '(utf-8-unix . utf-8-unix)
              locale-coding-system 'utf-8-unix)
(set-charset-priority 'unicode)
(prefer-coding-system 'utf-8-unix)
(set-default-coding-systems 'utf-8-unix)
(set-terminal-coding-system 'utf-8-unix)
(set-keyboard-coding-system 'utf-8-unix)
(pcase system-type
  ((or 'ms-dos 'windows-nt)
   (set-clipboard-coding-system 'utf-16-le)
   (set-selection-coding-system 'utf-16-le))
  (_
   (set-selection-coding-system 'utf-8)
   (set-clipboard-coding-system 'utf-8)))

;; Abbrev
(setq-default abbrev-file-name (sync/ "abbrev.el")
	      save-abbrevs 'silently)

;; Files
(setq-default auto-revert-verbose nil
	      global-auto-revert-non-file-buffers t
	      create-lockfiles nil
	      find-file-visit-truename t
	      mode-require-final-newline t
	      view-read-only t
	      save-silently t)
(global-auto-revert-mode)

(setq-default auto-save-default nil
	      auto-save-interval 1
	      auto-save-no-message t
	      auto-save-timeout 1
	      auto-save-visited-interval 1)
(add-to-list 'auto-save-file-name-transforms
	     `(".*" ,(etc/ "auto-save/" t) t))
(auto-save-visited-mode)

(setq-default backup-by-copying t
	      version-control t
	      kept-new-versions 8
	      kept-old-versions 8
	      delete-old-versions t)

(require 'recentf)
(setq-default ;; recentf-save-file (etc/ "recentf" t)
	      recentf-max-menu-items 500
	      recentf-max-saved-items nil ; Save the whole list
	      recentf-auto-cleanup 'mode)
(add-to-list 'recentf-exclude etc/)
(add-to-list 'recentf-exclude "-autoloads.el\\'")
(add-hook 'buffer-list-update-hook #'recentf-track-opened-file)
(recentf-mode)

(require 'saveplace)
(setq-default ;; save-place-file (etc/ "places.el")
	      save-place-forget-unreadable-files (eq system-type
						     'gnu/linux))
(save-place-mode)

(require 'uniquify)
(setq uniquify-after-kill-buffer-p t
      uniquify-buffer-name-style 'forward
      uniquify-ignore-buffers-re "^\\*"
      uniquify-separator path-separator)

(setq-local vc-follow-symlinks t
	    vc-make-backup-files t)

;; Native compilation
(setq-default native-comp-async-report-warnings-errors 'silent
	      native-comp-deferred-compilation t
	      native-compile-target-directory (etc/ "eln" t))
(add-to-list 'native-comp-eln-load-path native-compile-target-directory)
(when (fboundp 'startup-redirect-eln-cache)
  (startup-redirect-eln-cache native-compile-target-directory))

;; Custom file
(setq-default custom-file (sync/ "emacs/custom.el"))
(define-advice package--save-selected-packages (:around (orig &rest args) no-custom)
  "Don't save `package-selected-packages' to `custom-file'."
  (let ((custom-file null-device))
    (apply orig args)))

;; Goto Address
(if (fboundp 'global-goto-address-mode)
    (global-goto-address-mode)
  (add-hook 'after-change-major-mode-hook #'goto-address-mode))

;; Winner
(winner-mode)

;;; Keybindings

(defun other-window|switch-buffer (arg)
  "Call `other-window' or `switch-buffer' depending on windows.
When called with prefix ARG, unconditionally switch buffer."
  (interactive "P")
  (if (or arg (one-window-p))
      (switch-to-buffer (other-buffer) nil t)
    (other-window 1)))

(defun delete-window|bury-buffer ()
  "Delete the current window, or bury the current buffer.
If the current window is the only window, bury the buffer."
  (interactive)
  (condition-case e
      (delete-window)
    (t (bury-buffer))))

(defun +cycle-spacing (&optional n)
  ;; `cycle-spacing' is wildly different in 29.1 over 28.
  "Negate N argument on `cycle-spacing'.
That is, with a positive N, deletes newlines as well, leaving -N
spaces.  If N is negative, it will not delete newlines and leave
N spaces."
  (interactive "*p")
  (cycle-spacing (- n)))

(global-set-key [remap eval-expression] #'pp-eval-expression)
(global-set-key (kbd "M-o") #'other-window|switch-buffer)
(global-set-key (kbd "C-x 0") #'delete-window|bury-buffer)
(global-set-key (kbd "M-SPC") #'+cycle-spacing)
(global-set-key (kbd "C-x C-k") #'kill-this-buffer)

;;; Hooks

(add-hook 'after-save-hook #'executable-make-buffer-file-executable-if-script-p)
(add-hook 'find-file-not-found-functions
	  (defun create-missing-directories ()
	    "Automatically create missing directories."
	    (let ((target-dir (file-name-directory buffer-file-name)))
	      (unless (file-exists-p target-dir)
		(make-directory target-dir :parents)))))
(add-hook 'find-file-hook
	  (defun vc-remote-off ()
	    "Turn VC off when remote."
	    (when (file-remote-p (buffer-file-name))
	      (setq-local vc-handled-backends nil))))

;;; Advice

(define-advice switch-to-buffer (:after (&rest _) normal-mode)
  "Automatically determine the mode for non-file buffers."
  (when-let ((_ (and (eq major-mode 'fundamental-mode)))
             (buffer-file-name (buffer-name)))
    (normal-mode)))

(define-advice canonically-space-region
    (:around (orig &rest args) double-space-sentences)
  "Always double-space sentences canonically."
  (let ((sentence-end-double-space t))
    (apply orig args)))

;; With region or ...
(defun advise-region-or-buffer (&rest _)
  "`:before' advice to work on the active region or whole buffer.
See also `with-region-or-buffer'."
  (interactive (if mark-active
                   (list (region-beginning) (region-end))
                 (list (point-min) (point-max)))))

(defun advise-region-or-line (&rest _)
  "`:before' advice to work on the active region or whole line.
See also `with-region-or-line'."
  (interactive (if mark-active
                   (list (region-beginning) (region-end))
                 (list (line-beginning-position) (line-end-position)))))

(defun advise-region-or-to-eol (&rest _)
  "`:before' advice to work on the active region or to end of line.
See also `with-region-or-to-eol'."
  (INTERACTIVE (if mark-active
                   (list (region-beginning) (region-end))
                 (list (point) (line-end-position)))))

(defmacro with-region-or-buffer (&rest funcs)
  "Advise FUNCS with `advise-region-or-buffer'."
  `(progn
     ,@(cl-loop for fn in funcs
                collect
                `(advice-add ',fn :before #'advise-region-or-buffer))))

(defmacro with-region-or-line (&rest funcs)
  "Advise FUNCS with `advise-region-or-line'."
  `(progn
     ,@(cl-loop for fn in funcs
                collect
                `(advice-add ',fn :before #'advise-region-or-line))))

(defmacro with-region-or-to-eol (&rest funcs)
  "Advise FUNCS with `advise-region-or-to-eol'."
  `(progn
     ,@(cl-loop for fn in funcs
                collect
                `(advice-add ',fn :before #'advise-region-or-to-eol))))

(with-region-or-buffer indent-region)

;;; Packages

(use-package _acdw
  :load-path private/)

;;; basics.el ends here