light-rofime.el

;; LightRoFIME: Ring of Favorite Input MEthods, modified by shchoi
;; RoFIME created by slomo at KLDP https://kldp.org/node/109184
;; Modified by shchoi https://web.sfc.keio.ac.jp/~t21526hc/blog/

;; Set your favorite input methods
(setq favorite-input-methods
      '(nil "korean-hangul" "japanese"))
(setq default-input-method "korean-hangul")

;; Set key bindings
(global-set-key (kbd "S-SPC") 'toggle-the-other-input-method)
(global-set-key (kbd "C-S-SPC") 'toggle-ring-structure)

;; load settings
(cond
 ((boundp 'favorite-input-methods)
  (setq input-method-ring favorite-input-methods))
 (T (setq input-method-ring () )))
(cond
 ((boundp 'default-input-method)
  (add-to-list 'input-method-ring default-input-method)))

;; functions
(defun rofime-swap-heads (ring)
  (cons (cadr ring)
        (cons (car ring)
              (cddr ring))))

(defun rofime-swap-the-ends (ring)
  (append (last ring)
          (append (reverse (cdr (reverse (cdr ring))))
                  (list (car ring)))))

(defun rofime-rotate (ring)
  (if (< (length ring) 2) ring
    (append (cdr ring) (list (car ring)))))

(defun rofime-add (ime)
  (add-to-list 'input-method-ring ime))

(defun rofime-message () (interactive)
       (message "%S" input-method-ring))

(defun toggle-the-other-input-method() (interactive)
       (rofime-add current-input-method)
       (setq input-method-ring
             (rofime-swap-heads input-method-ring))
       (set-input-method (car input-method-ring))
       (rofime-message))

(defun rofime-rotate-the-others (ring)
        (cons (car ring)
              (rofime-rotate (cdr ring))))

(defun toggle-ring-structure () (interactive)
       (if (equal (car input-method-ring) nil)
           (setq input-method-ring
                 (rofime-rotate-the-others (reverse input-method-ring)))
           (setq input-method-ring
                 (rofime-swap-the-ends input-method-ring)))
       (set-input-method (car input-method-ring))
       (rofime-message))