;;; core-ui.el -*- lexical-binding: t; -*-

(defvar doom-theme nil
  "A symbol representing the Emacs theme to load at startup.

This is changed when `load-theme' is used as well.")

(defvar doom-font nil
  "The default font to use.

Expects either a `font-spec', font object, an XFT font string or an XLFD font
string.

This affects the `default' and `fixed-pitch' faces.

Examples:
  (setq doom-font (font-spec :family \"Fira Mono\" :size 12))
  (setq doom-font \"Terminus (TTF):pixelsize=12:antialias=off\")")

(defvar doom-big-font nil
  "The font to use when `doom-big-font-mode' is enabled. Expects either a
`font-spec' or a XFT font string. See `doom-font' for examples.")

(defvar doom-variable-pitch-font nil
  "The font to use for variable-pitch text.

Expects either a `font-spec', font object, a XFT font string or XLFD string. See
`doom-font' for examples.

It is recommended you don't set specify a font-size, as to inherit `doom-font's
size.")

(defvar doom-serif-font nil
  "The default font to use for the `fixed-pitch-serif' face.

Expects either a `font-spec', font object, a XFT font string or XLFD string. See
`doom-font' for examples.

It is recommended you don't set specify a font-size, as to inherit `doom-font's
size.")

(defvar doom-unicode-font nil
  "Fallback font for unicode glyphs. Is ignored if :feature unicode is active.

Expects either a `font-spec', font object, a XFT font string or XLFD string. See
`doom-font' for examples.

It is recommended you don't set specify a font-size, as to inherit `doom-font's
size.")


;;
(defvar doom-init-ui-hook nil
  "List of hooks to run when the UI has been initialized.")

(defvar doom--prefer-theme-elc nil
  "If non-nil, `load-theme' will prefer the compiled theme (unlike its default
behavior). Do not set this directly, this is let-bound in `doom|init-theme'.")

(setq-default
 ansi-color-for-comint-mode t
 bidi-display-reordering nil ; disable bidirectional text for tiny performance boost
 blink-matching-paren nil    ; don't blink--too distracting
 compilation-always-kill t        ; kill compilation process before starting another
 compilation-ask-about-save nil   ; save all buffers on `compile'
 compilation-scroll-output 'first-error
 confirm-nonexistent-file-or-buffer t
 confirm-kill-emacs #'doom-quit-p   ; custom confirmation when killing Emacs
 cursor-in-non-selected-windows nil ; hide cursors in other windows
 custom-theme-directory (expand-file-name "themes/" doom-private-dir)
 display-line-numbers-width 3
 enable-recursive-minibuffers nil
 frame-inhibit-implied-resize t
 ;; remove continuation arrow on right fringe
 fringe-indicator-alist
 (delq (assq 'continuation fringe-indicator-alist)
       fringe-indicator-alist)
 highlight-nonselected-windows nil
 image-animate-loop t
 indicate-buffer-boundaries nil
 indicate-empty-lines nil
 inhibit-compacting-font-caches t
 max-mini-window-height 0.3
 mode-line-default-help-echo nil ; disable mode-line mouseovers
 mouse-yank-at-point t           ; middle-click paste at point, not at click
 resize-mini-windows 'grow-only  ; Minibuffer resizing
 show-help-function nil          ; hide :help-echo text
 split-width-threshold 160       ; favor horizontal splits
 uniquify-buffer-name-style 'forward
 use-dialog-box nil              ; always avoid GUI
 visible-cursor nil
 x-stretch-cursor nil
 ;; `pos-tip' defaults
 pos-tip-internal-border-width 6
 pos-tip-border-width 1
 ;; no beeping or blinking please
 ring-bell-function #'ignore
 visible-bell nil
 ;; don't resize emacs in steps, it looks weird
 window-resize-pixelwise t
 frame-resize-pixelwise t)

;; y/n instead of yes/no
(fset #'yes-or-no-p #'y-or-n-p)

;; Truly silence startup message
(fset #'display-startup-echo-area-message #'ignore)


;;
;; Third party packages

;; `avy'
(setq avy-all-windows nil
      avy-background t)

;; `all-the-icons'
(def-package! all-the-icons
  :commands (all-the-icons-octicon all-the-icons-faicon all-the-icons-fileicon
             all-the-icons-wicon all-the-icons-material all-the-icons-alltheicon)
  :init
  (defun doom*disable-all-the-icons-in-tty (orig-fn &rest args)
    (if (display-graphic-p)
        (apply orig-fn args)
      ""))
  :config
  ;; all-the-icons doesn't work in the terminal, so we "disable" it.
  (dolist (fn '(all-the-icons-octicon all-the-icons-material
                all-the-icons-faicon all-the-icons-fileicon
                all-the-icons-wicon all-the-icons-alltheicon))
    (advice-add fn :around #'doom*disable-all-the-icons-in-tty)))

;; `hide-mode-line-mode'
(add-hook 'completion-list-mode-hook #'hide-mode-line-mode)
(add-hook 'Man-mode-hook #'hide-mode-line-mode)

;; `highlight-numbers' --- better number literal fontification in code
(def-package! highlight-numbers
  :hook ((prog-mode conf-mode) . highlight-numbers-mode)
  :config (setq highlight-numbers-generic-regexp "\\_<[[:digit:]]+\\(?:\\.[0-9]*\\)?\\_>"))

;; `highlight-escape-sequences'
(def-package! highlight-escape-sequences
  :hook ((prog-mode conf-mode) . highlight-escape-sequences-mode))

;; `rainbow-delimiters' --- helps us distinguish stacked delimiter pairs.
;; Especially in parentheses-drunk languages like Lisp.
(setq rainbow-delimiters-max-face-count 3)

;; `restart-emacs' --- provides a simple mechanism for restarting Emacs and
;; daemons interactively.
(setq restart-emacs--args (list "--restore"))

;; `visual-fill-column' --- for a distractions-free-like UI, that dynamically
;; resizes margins and can center a buffer.
(setq visual-fill-column-center-text t
      visual-fill-column-width
      ;; take Emacs 26 line numbers into account
      (+ (if EMACS26+ 6 0) fill-column))


;;
;; Built-in packages

(def-package! ediff
  :defer t
  :init
  (setq ediff-diff-options "-w" ; turn off whitespace checking
        ediff-split-window-function #'split-window-horizontally
        ediff-window-setup-function #'ediff-setup-windows-plain)
  :config
  ;; Restore window config after quitting ediff
  (defun doom|ediff-save-wconf ()
    (setq +ediff--saved-wconf (current-window-configuration)))
  (add-hook 'ediff-before-setup-hook #'doom|ediff-save-wconf)

  (defun doom|ediff-restore-wconf ()
    (set-window-configuration +ediff--saved-wconf))
  (add-hook 'ediff-quit-hook #'doom|ediff-restore-wconf 'append)
  (add-hook 'ediff-suspend-hook #'doom|ediff-restore-wconf 'append))


(def-package! hl-line
  ;; Highlights the current line
  :hook ((prog-mode text-mode conf-mode) . hl-line-mode)
  :config
  ;; I don't need hl-line showing in other windows. This also offers a small
  ;; speed boost when buffer is displayed in multiple windows.
  (setq hl-line-sticky-flag nil
        global-hl-line-sticky-flag nil)

  ;; On Emacs 26+, when point is on the last line, hl-line highlights bleed into
  ;; the rest of the window after eob. This is the fix.
  (when EMACS26+
    (defun doom--line-range ()
      (cons (line-beginning-position)
            (cond ((let ((eol (line-end-position)))
                     (and (=  eol (point-max))
                          (/= eol (line-beginning-position))))
                   (1- (line-end-position)))
                  ((or (eobp)
                       (= (line-end-position 2) (point-max)))
                   (line-end-position))
                  ((line-beginning-position 2)))))
    (setq hl-line-range-function #'doom--line-range))

  ;; Disable `hl-line' in evil-visual mode (temporarily). `hl-line' can make the
  ;; selection region harder to see while in evil visual mode.
  (after! evil
    (defvar-local doom-buffer-hl-line-mode nil)
    (defun doom|disable-hl-line ()
      (when hl-line-mode
        (setq doom-buffer-hl-line-mode t)
        (hl-line-mode -1)))
    (defun doom|enable-hl-line-maybe ()
      (if doom-buffer-hl-line-mode (hl-line-mode +1)))
    (add-hook 'evil-visual-state-entry-hook #'doom|disable-hl-line)
    (add-hook 'evil-visual-state-exit-hook  #'doom|enable-hl-line-maybe)))


(def-package! winner
  ;; undo/redo changes to Emacs' window layout
  :after-call doom-exit-window-hook
  :preface (defvar winner-dont-bind-my-keys t) ; I'll bind keys myself
  :config (winner-mode +1))


(def-package! paren
  ;; highlight matching delimiters
  :after-call (after-find-file doom-exit-buffer-hook)
  :init
  (defun doom|disable-show-paren-mode ()
    "Turn off `show-paren-mode' buffer-locally."
    (set (make-local-variable 'show-paren-mode) nil))
  :config
  (setq show-paren-delay 0.1
        show-paren-highlight-openparen t
        show-paren-when-point-inside-paren t)
  (show-paren-mode +1))


;; The native border "consumes" a pixel of the fringe on righter-most splits,
;; `window-divider' does not. Available since Emacs 25.1.
(setq-default window-divider-default-places t
              window-divider-default-bottom-width 1
              window-divider-default-right-width 1)
(add-hook 'doom-init-ui-hook #'window-divider-mode)


;; `whitespace-mode'
(setq whitespace-line-column nil
      whitespace-style
      '(face indentation tabs tab-mark spaces space-mark newline newline-mark
             trailing lines-tail)
      whitespace-display-mappings
      '((tab-mark ?\t [?› ?\t])
        (newline-mark ?\n [?¬ ?\n])
        (space-mark ?\  [?·] [?.])))


;;
;; Line numbers

;; line numbers in most modes
(add-hook! (prog-mode text-mode conf-mode) #'display-line-numbers-mode)

(defun doom|enable-line-numbers ()  (display-line-numbers-mode +1))
(defun doom|disable-line-numbers () (display-line-numbers-mode -1))

;; Emacs 26+ has native line number support, and will ignore nlinum. This is for
;; Emacs 25 users:
(def-package! nlinum
  ;; Line number column. A faster (or equivalent, in the worst case) line number
  ;; plugin than `linum-mode'.
  :unless EMACS26+
  :defer t
  :init
  (defvar doom-line-number-lpad 4
    "How much padding to place before line numbers.")
  (defvar doom-line-number-rpad 1
    "How much padding to place after line numbers.")
  (defvar doom-line-number-pad-char 32
    "Character to use for padding line numbers.

By default, this is a space character. If you use `whitespace-mode' with
`space-mark', the whitespace in line numbers will be affected (this can look
ugly). In this case, you can change this to ?\u2002, which is a unicode
character that looks like a space that `whitespace-mode' won't affect.")
  :config
  (setq nlinum-highlight-current-line t)

  ;; Fix lingering hl-line overlays (caused by nlinum)
  (add-hook! 'hl-line-mode-hook
    (remove-overlays (point-min) (point-max) 'face 'hl-line))

  (defun doom-nlinum-format-fn (line _width)
    "A more customizable `nlinum-format-function'. See `doom-line-number-lpad',
`doom-line-number-rpad' and `doom-line-number-pad-char'. Allows a fix for
`whitespace-mode' space-marks appearing inside the line number."
    (let ((str (number-to-string line)))
      (setq str (concat (make-string (max 0 (- doom-line-number-lpad (length str)))
                                     doom-line-number-pad-char)
                        str
                        (make-string doom-line-number-rpad doom-line-number-pad-char)))
      (put-text-property 0 (length str) 'face
                         (if (and nlinum-highlight-current-line
                                  (= line nlinum--current-line))
                             'nlinum-current-line
                           'linum)
                         str)
      str))
  (setq nlinum-format-function #'doom-nlinum-format-fn)

  (defun doom|init-nlinum-width ()
    "Calculate line number column width beforehand (optimization)."
    (setq nlinum--width
          (length (save-excursion (goto-char (point-max))
                                  (format-mode-line "%l")))))
  (add-hook 'nlinum-mode-hook #'doom|init-nlinum-width))

(def-package! nlinum-hl
  ;; Fixes disappearing line numbers in nlinum and other quirks
  :unless EMACS26+
  :after nlinum
  :config
  ;; With `markdown-fontify-code-blocks-natively' enabled in `markdown-mode',
  ;; line numbers tend to vanish next to code blocks.
  (advice-add #'markdown-fontify-code-block-natively
              :after #'nlinum-hl-do-markdown-fontify-region)
  ;; When using `web-mode's code-folding an entire range of line numbers will
  ;; vanish in the affected area.
  (advice-add #'web-mode-fold-or-unfold :after #'nlinum-hl-do-generic-flush)
  ;; Changing fonts can leave nlinum line numbers in their original size; this
  ;; forces them to resize.
  (advice-add #'set-frame-font :after #'nlinum-hl-flush-all-windows))

(def-package! nlinum-relative
  :unless EMACS26+
  :defer t
  :config
  (setq nlinum-format " %d ")
  (add-hook 'evil-mode #'nlinum-relative-setup-evil))


;;
;; Theme & font

(defvar doom-last-window-system
  (if (daemonp) 'daemon initial-window-system)
  "The `window-system' of the last frame. If this doesn't match the current
frame's window-system, the theme will be reloaded.")

(defun doom|init-fonts ()
  "Initialize fonts."
  (condition-case e
      (progn
        (cond (doom-font
               ;; We avoid `set-frame-font' for performance reasons.
               ;; Manipulating `default-frame-alist' is effective enough.
               (add-to-list
                'default-frame-alist
                (cons 'font
                      (cond ((stringp doom-font) doom-font)
                            ((fontp doom-font) (font-xlfd-name doom-font))
                            ((signal 'wrong-type-argument (list '(fontp stringp) doom-font)))))))
              ((display-graphic-p)
               (setq doom-font (face-attribute 'default :font))))
        (when doom-serif-font
          (set-face-attribute 'fixed-pitch-serif nil :font doom-serif-font))
        (when doom-variable-pitch-font
          (set-face-attribute 'variable-pitch nil :font doom-variable-pitch-font))
        ;; Fallback to `doom-unicode-font' for Unicode characters
        (when (fontp doom-unicode-font)
          (set-fontset-font t nil doom-unicode-font nil 'append)))
    ((debug error)
     (if (string-prefix-p "Font not available: " (error-message-string e))
         (lwarn 'doom-ui :warning
                "Could not find the '%s' font on your system, falling back to system font"
                (font-get (caddr e) :family))
       (signal 'doom-error e)))))

(defun doom|init-theme ()
  "Set the theme and load the font, in that order."
  (when (and doom-theme (not (memq doom-theme custom-enabled-themes)))
    (let ((doom--prefer-theme-elc t))
      (load-theme doom-theme t))))

;; Getting themes to remain consistent across GUI Emacs, terminal Emacs and
;; daemon Emacs is hairy. `doom|init-theme' sorts out the initial GUI frame.
;; Attaching `doom|init-theme-in-frame' to `after-make-frame-functions' sorts
;; out daemon and emacsclient frames.
;;
;; There will still be issues with simultaneous gui and terminal (emacsclient)
;; frames, however. There's always `doom/reload-theme' if you need it!
(defun doom|reload-theme-in-frame-maybe (frame)
  "Reloads the theme in new daemon or tty frames."
  (when (and doom-theme
             (framep frame)
             (not (eq doom-last-window-system (framep-on-display frame))))
    (with-selected-frame frame
      (load-theme doom-theme t))
    (setq doom-last-window-system (framep-on-display frame))))

(defun doom|reload-theme-maybe (_frame)
  "Reloads the theme after closing the last frame of a type."
  (unless (cl-find doom-last-window-system (frame-list) :key #'framep-on-display)
    (setq doom-last-window-system nil)
    (doom|reload-theme-in-frame (selected-frame))))

;; fonts
(add-hook 'doom-init-ui-hook #'doom|init-fonts)
;; themes
(unless (daemonp)
  (add-hook 'doom-init-ui-hook #'doom|init-theme))
(add-hook 'after-make-frame-functions #'doom|reload-theme-in-frame-maybe)
(add-hook 'after-delete-frame-functions #'doom|reload-theme-maybe)


;;
;; Bootstrap

;; simple name in frame title
(setq frame-title-format '("%b – Doom Emacs"))

;; relegate tooltips to echo area only
(if (boundp 'tooltip-mode) (tooltip-mode -1))

;; enabled by default; no thanks, too distracting
(blink-cursor-mode -1)

;; Handle ansi codes in compilation buffer
(add-hook 'compilation-filter-hook #'doom|apply-ansi-color-to-compilation-buffer)

;; show typed keystrokes in minibuffer
(defun doom|enable-ui-keystrokes ()  (setq echo-keystrokes 0.02))
(defun doom|disable-ui-keystrokes () (setq echo-keystrokes 0))
(doom|enable-ui-keystrokes)
;; ...but hide them while isearch is active
(add-hook 'isearch-mode-hook     #'doom|disable-ui-keystrokes)
(add-hook 'isearch-mode-end-hook #'doom|enable-ui-keystrokes)

;; Make `next-buffer', `other-buffer', etc. ignore unreal buffers.
(add-to-list 'default-frame-alist '(buffer-predicate . doom-buffer-frame-predicate))
;; Prevent the glimpse of un-styled Emacs by setting these early.
(add-to-list 'default-frame-alist '(tool-bar-lines . 0))
(add-to-list 'default-frame-alist '(menu-bar-lines . 0))
(add-to-list 'default-frame-alist '(vertical-scroll-bars))
;; prompts the user for confirmation when deleting a non-empty frame
(global-set-key [remap delete-frame] #'doom/delete-frame)

(defun doom|protect-visible-buffer ()
  "Don't kill the current buffer if it is visible in another window (bury it
instead). Meant for `kill-buffer-query-functions'."
  (not (and (delq (selected-window) (get-buffer-window-list nil nil t))
            (not (member (substring (buffer-name) 0 1) '(" " "*"))))))

(defun doom|protect-fallback-buffer ()
  "Don't kill the scratch buffer. Meant for `kill-buffer-query-functions'."
  (not (eq (current-buffer) (doom-fallback-buffer))))

(defun doom|highlight-non-default-indentation ()
  "Highlight whitespace that doesn't match your `indent-tabs-mode' setting.

e.g. If you indent with spaces by default, tabs will be highlighted. If you
indent with tabs, spaces at BOL are highlighted.

Does nothing if `whitespace-mode' is already active or the current major mode is
derived from `special-mode'."
  (unless (or (bound-and-true-p global-whitespace-mode)
              (bound-and-true-p whitespace-mode)
              (eq major-mode 'fundamental-mode)
              (eq (get major-mode 'mode-class) 'special)
              (derived-mode-p 'special-mode)
              buffer-read-only)
    (require 'whitespace)
    (set (make-local-variable 'whitespace-style)
         (if (bound-and-true-p whitespace-newline-mode)
             (cl-union (if indent-tabs-mode '(indentation) '(tabs tab-mark))
                       whitespace-style)
           `(face ,@(if indent-tabs-mode '(indentation) '(tabs tab-mark))
             trailing-lines tail)))
    (whitespace-mode +1)))

(defun doom|init-ui ()
  "Initialize Doom's user interface by applying all its advice and hooks."
  (add-to-list 'kill-buffer-query-functions #'doom|protect-fallback-buffer nil #'eq)
  (add-to-list 'kill-buffer-query-functions #'doom|protect-visible-buffer  nil #'eq)
  (add-hook 'after-change-major-mode-hook #'doom|highlight-non-default-indentation)
  (run-hook-wrapped 'doom-init-ui-hook #'doom-try-run-hook))

(add-hook 'emacs-startup-hook #'doom|init-ui)


;;
;; Fixes/hacks

;; doesn't exist in terminal Emacs; we define it to prevent errors
(unless (fboundp 'define-fringe-bitmap)
  (defun define-fringe-bitmap (&rest _)))

(defun doom*disable-old-themes-first (orig-fn &rest args)
  (mapc #'disable-theme custom-enabled-themes)
  (apply orig-fn args)
  (when (fboundp 'powerline-reset)
    (powerline-reset)))
(advice-add #'load-theme :around #'doom*disable-old-themes-first)

(defun doom*prefer-compiled-theme (orig-fn &rest args)
  "Make `load-theme' prioritize the byte-compiled theme for a moderate boost in
startup (or theme switch) time, so long as `doom--prefer-theme-elc' is non-nil."
  (if (or (null after-init-time)
          doom--prefer-theme-elc)
      (cl-letf* ((old-locate-file (symbol-function 'locate-file))
                 ((symbol-function 'locate-file)
                  (lambda (filename path &optional _suffixes predicate)
                    (funcall old-locate-file filename path '("c" "") predicate))))
        (apply orig-fn args))
    (apply orig-fn args)))
(advice-add #'load-theme :around #'doom*prefer-compiled-theme)

(defun doom|disable-whitespace-mode-in-childframes (frame)
  "`whitespace-mode' inundates child frames with whitspace markers, so disable
it to fix all that visual noise."
  (when (frame-parameter frame 'parent-frame)
    (with-selected-frame frame
      (setq-local whitespace-style nil)
      frame)))
(add-hook 'after-make-frame-functions #'doom|disable-whitespace-mode-in-childframes)

(defun doom*silence-motion-errors (orig-fn &rest args)
  "Prevent disruptive motion errors taking over the minibuffer while we're in
it."
  (if (not (minibufferp))
      (apply orig-fn args)
    (ignore-errors (apply orig-fn args))
    (when (<= (point) (minibuffer-prompt-end))
      (goto-char (minibuffer-prompt-end)))))
(advice-add #'left-char :around #'doom*silence-motion-errors)
(advice-add #'right-char :around #'doom*silence-motion-errors)
(advice-add #'delete-backward-char :around #'doom*silence-motion-errors)
(advice-add #'backward-kill-sentence :around #'doom*silence-motion-errors)

;; Switch to `doom-fallback-buffer' if on last real buffer
(advice-add #'kill-this-buffer :around #'doom*switch-to-fallback-buffer-maybe)

(provide 'core-ui)
;;; core-ui.el ends here