tvl-depot/configs/shared/.emacs.d/wpc/wallpaper.el
William Carroll 5785a5d126 Support prelude/start-process
If you refer to the previous commit where I change shell-command usages to
start-process function calls, you'll see the rationale for why I prefer
start-process.

This commit introduces a more ergonomic API for start-process that fits most of
my current use-cases of it. This cleans up the code. I have introduced a bug in
the way that I'm tokenizing the COMMAND value. I've tracked that with a
TODO. For now it only affects the `xmodmap -e '<command-string>'` calls, which
isn't too disruptive.
2020-01-06 15:25:25 +00:00

89 lines
2.8 KiB
EmacsLisp

;;; wallpaper.el --- Control Linux desktop wallpaper -*- lexical-binding: t -*-
;; Author: William Carroll <wpcarro@gmail.com>
;;; Commentary:
;; Functions for setting desktop wallpaper.
;;; Code:
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Dependencies
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(require 'prelude)
(require 'fs)
(require 'cycle)
(require 'string)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Library
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(defcustom wallpaper/keybindings? t
"If non-nil, install the keybindings.")
(defcustom wallpaper/path-to-dir
(f-expand "~/.local/share/wallpaper")
"Path to the images that will be used as the wallpaper.")
(defconst wallpaper/whitelist
(cycle/from-list
(fs/ls wallpaper/path-to-dir t))
"My preferred computer wallpapers.")
(defun wallpaper/set (path)
"Set computer wallpaper to image at `PATH' using `feh` under-the-hood.
`PATH' can be absolute or relative since `f-expand' is called in the function
body to ensure feh can resolve the path."
(prelude/start-process
:name "wallpaper/set"
:command (string/format "feh --bg-scale --no-feh-bg %s" (f-expand path))))
(defun wallpaper/whitelist-set (wallpaper)
"Focuses the WALLPAPER in the `wallpaper/whitelist' cycle."
(cycle/focus (lambda (x) (equal x wallpaper)) wallpaper/whitelist)
(wallpaper/set (wallpaper/current)))
(defun wallpaper/next ()
"Cycles to the next wallpaper."
(interactive)
(let ((wallpaper (cycle/next wallpaper/whitelist)))
(wallpaper/set wallpaper)
(message (string/format "Active wallpaper: %s" (f-filename wallpaper)))))
(defun wallpaper/prev ()
"Cycles to the previous wallpaper."
(interactive)
(let ((wallpaper (cycle/prev wallpaper/whitelist)))
(wallpaper/set wallpaper)
(message (string/format "Active wallpaper: %s" (f-filename wallpaper)))))
;; TODO: Define a macro that handles, next, prev, select, current for working
;; with cycles, since this is a common pattern.
(defun wallpaper/print-current ()
"Message the currently enabled wallpaper."
(interactive)
(message
(cycle/current wallpaper/whitelist)))
(defun wallpaper/current ()
"Return the currently enabled wallpaper."
(cycle/current wallpaper/whitelist))
(defun wallpaper/ivy-select ()
"Use `counsel' to select and set a wallpaper from the `wallpaper/whitelist'."
(interactive)
(wallpaper/whitelist-set
(ivy-read "Select wallpaper: " (cycle/to-list wallpaper/whitelist))))
;; TODO: Create macro-based module system that will auto-namespace functions,
;; constants, etc. with the filename like `wallpaper'.
(when wallpaper/keybindings?
(evil-leader/set-key
"Fw" #'wallpaper/next
"Pw" #'wallpaper/prev))
(provide 'wallpaper)
;;; wallpaper.el ends here