.emacs.d/init.d/basics/input.el

;;; input.el --- Configure behaviour of input devices. -*- lexical-binding: t; -*-

;; Time-stamp: <2020-03-29T22:58:40+0200>

;;; Commentary:
;; * Setup mouse & keyboard behaviour.
;; * Setup basic keybindings.

;;; Code:

(require 'basics/package-management)

(use-package emacs
  :custom ((mouse-wheel-scroll-amount '(1 ((shift) . 1))) ; Scroll 1 line.
           ;; Paste text where the cursor is, not where the mouse is.
           (mouse-yank-at-point t)
           ;; Reduce scroll lag. <https://emacs.stackexchange.com/a/28746>
           (auto-window-vscroll nil))
  :config (progn
            (delete-selection-mode t) ; Delete selection when you start to write.
            ;; kill-region (cut) and kill-ring-save (copy) act on the current
            ;; line if no text is visually selected.
            ;; <https://www.emacswiki.org/emacs/WholeLineOrRegion>
            (put 'kill-ring-save 'interactive-form
                 '(interactive
                   (if (use-region-p)
                       (list (region-beginning) (region-end))
                     (list (line-beginning-position)
                           (line-beginning-position 2)))))
            (put 'kill-region 'interactive-form
                 '(interactive
                   (if (use-region-p)
                       (list (region-beginning) (region-end))
                     (list (line-beginning-position)
                           (line-beginning-position 2)))))))

(use-package bind-key
  :functions (my/delete-word my/backward-delete-word)
  :config (progn
            (defun my/delete-word (arg)
              "Delete characters forward until encountering the end of a word.
With ARG, do it that many times."
              (interactive "p")
              (if (use-region-p)
                  (delete-region (region-beginning) (region-end))
                (delete-region (point) (progn (forward-word arg) (point)))))

            (defun my/backward-delete-word (arg)
              "Delete characters backward until encountering the end of a word.
With ARG, do it that many times."
              (interactive "p")
              (my/delete-word (- arg)))
            (bind-keys
             ;; Reduce whitespace around cursor to 0 or 1, according to context.
             ("C-S-<delete>"  . fixup-whitespace)
             ;; Scroll without moving the cursor.
             ("M-<down>"      . scroll-up-line)
             ("M-<up>"        . scroll-down-line)
             ;; Delete words without storing them in the kill buffer.
             ("C-<delete>"    . my/delete-word)
             ("C-<backspace>" . my/backward-delete-word)
             ("C-DEL"         . my/backward-delete-word)
             ("C-q"           . delete-frame)
             ;; Insert next character with control characters.
             ("C-S-v"         . quoted-insert)
             ;; C-x C-f will be replaced with projectile-find-file.
             ("C-x C-S-f"     . find-file)
             ("C-x F"         . find-file)))) ; Workaround for terminals.

; Multiple cursors.
(use-package multiple-cursors
  :init (global-unset-key (kbd "M-<down-mouse-1>"))
  :bind (("C-c m"       . mc/edit-lines)
         ("M-<mouse-1>" . mc/add-cursor-on-click)))

;; Edit multiple regions in the same way simultaneously.
(use-package iedit
  :bind ("C-;" . iedit-mode))

;; Display available keybindings.
(use-package which-key
  :diminish which-key-mode
  :config (which-key-mode))

;; Navigate between windows with alt+arrows.
(use-package windmove
  :config (windmove-default-keybindings '(meta shift))
  :bind (([(meta shift left)] . windmove-left) ; Needed for Emacs-over-SSH. 🤷
         ([(meta shift right)] . windmove-right)
         ([(meta shift up)] . windmove-up)
         ([(meta shift down)] . windmove-down)))

(provide 'basics/input)
;;; input.el ends here