;-------------------------------------------------------------------
; bookmark-bmenu-next-line
; bookmark-bmenu-previous-line
; bookmark-bmenu-forward-char
; bookmark-bmenu-backward-char
;
; Functions to address bug in which the `*Bookmark Annotation*' buffer
; is not modified or updated when navigating through the
; bookmark-bmenu-list.
;
; Also provides option to auto-display annotations as one navigates
; the bmenu-list

(defvar bookmark-bmenu-auto-display-annotations nil
"Whether to automatically display a bookmark's annotation as one
navigates through the bookmark list. `t' for yes. Default is
`nil'.")

(defun bookmark-bmenu-next-line (&optional ARG TRY-VSCROLL)
"Move cursor vertically down ARG lines within the bookmark list.
Refer to function `next-line' for details."
  (interactive "^p\np")
  (let
    ((annotation-buffer
       (get-buffer "*Bookmark Annotation*")))
    (when annotation-buffer
      (kill-buffer annotation-buffer)))
  (next-line ARG TRY-VSCROLL)
  (when bookmark-bmenu-auto-display-annotations
     (bookmark-bmenu-show-annotation)))

(defun bookmark-bmenu-previous-line (&optional ARG TRY-VSCROLL)
"Move cursor vertically up ARG lines within the bookmark list.
Refer to function `previous-line' for details."
  (interactive "^p\np")
  (let
    ((annotation-buffer
       (get-buffer "*Bookmark Annotation*")))
    (when annotation-buffer
      (kill-buffer annotation-buffer)))
  (previous-line ARG TRY-VSCROLL)
  (when bookmark-bmenu-auto-display-annotations
     (bookmark-bmenu-show-annotation)))

(defun bookmark-bmenu-forward-char (&optional N)
  (interactive "p")
  (bookmark-bmenu-backward-forward-char 'forward-char N))

(defun bookmark-bmenu-backward-char (&optional N)
  (interactive "p")
  (bookmark-bmenu-backward-forward-char 'backward-char N))

(defun bookmark-bmenu-backward-forward-char (direction-function N)
  (let (annotation-buffer
        (initial-line (line-number-at-pos)))
    (funcall direction-function N)
    (when (/= initial-line (line-number-at-pos))
      (when (setq annotation-buffer (get-buffer "*Bookmark Annotation*"))
        (kill-buffer annotation-buffer))
      (when bookmark-bmenu-auto-display-annotations
        (bookmark-bmenu-show-annotation)))))

;-------------------------------------------------------------------
;
; ONLY ONE OF THE FOLLOWING TWO OPTIONS ARE NECESSARY !
;
; Either redine the mode map, or just the individual keys
;
;-------------------------------------------------------------------
(defvar bookmark-bmenu-mode-map
  (let ((map (make-keymap)))
    (set-keymap-parent map special-mode-map)
    (define-key map "v" 'bookmark-bmenu-select)
    (define-key map "w" 'bookmark-bmenu-locate)
    (define-key map "2" 'bookmark-bmenu-2-window)
    (define-key map "1" 'bookmark-bmenu-1-window)
    (define-key map "j" 'bookmark-bmenu-this-window)
    (define-key map "\C-c\C-c" 'bookmark-bmenu-this-window)
    (define-key map "f" 'bookmark-bmenu-this-window)
    (define-key map "\C-m" 'bookmark-bmenu-this-window)
    (define-key map "o" 'bookmark-bmenu-other-window)
    (define-key map "\C-o" 'bookmark-bmenu-switch-other-window)
    (define-key map "s" 'bookmark-bmenu-save)
    (define-key map "k" 'bookmark-bmenu-delete)
    (define-key map "\C-d" 'bookmark-bmenu-delete-backwards)
    (define-key map "x" 'bookmark-bmenu-execute-deletions)
    (define-key map "d" 'bookmark-bmenu-delete)
    (define-key map " " 'bookmark-bmenu-next-line)
    (define-key map "n" 'bookmark-bmenu-next-line)
    (define-key map [remap next-line] 'bookmark-bmenu-next-line)
    (define-key map "p" 'bookmark-bmenu-previous-line)
    (define-key map [remap previous-line] 'bookmark-bmenu-previous-line)
    (define-key map "\177" 'bookmark-bmenu-backup-unmark)
    (define-key map "u" 'bookmark-bmenu-unmark)
    (define-key map "m" 'bookmark-bmenu-mark)
    (define-key map "l" 'bookmark-bmenu-load)
    (define-key map "r" 'bookmark-bmenu-rename)
    (define-key map "R" 'bookmark-bmenu-relocate)
    (define-key map "t" 'bookmark-bmenu-toggle-filenames)
    (define-key map "a" 'bookmark-bmenu-show-annotation)
    (define-key map "A" 'bookmark-bmenu-show-all-annotations)
    (define-key map "e" 'bookmark-bmenu-edit-annotation)
    (define-key map "/" 'bookmark-bmenu-search)
    (define-key map [remap backward-char] 'bookmark-bmenu-backward-char)
    (define-key map [remap forward-char]  'bookmark-bmenu-forward-char)
    (define-key map [mouse-2] 'bookmark-bmenu-other-window-with-mouse)
    map))


(eval-after-load "bookmark"
  (progn
    (define-key bookmark-bmenu-mode-map
      [remap next-line] 'bookmark-bmenu-next-line)
    (define-key bookmark-bmenu-mode-map
      [remap previous-line] 'bookmark-bmenu-previous-line)
    (define-key bookmark-bmenu-mode-map
      (kbd "n")   'bookmark-bmenu-next-line)
    (define-key bookmark-bmenu-mode-map
      (kbd "SPC") 'bookmark-bmenu-next-line)
    (define-key bookmark-bmenu-mode-map
      (kbd "p")   'bookmark-bmenu-previous-line)
    (define-key bookmark-bmenu-mode-map
      [remap backward-char] 'bookmark-bmenu-backward-char)
    (define-key bookmark-bmenu-mode-map
      [remap forward-char]  'bookmark-bmenu-forward-char)
  ))
;-------------------------------------------------------------------


;-------------------------------------------------------------------
; Modification to function `bookmark-bmenu-show-annotation' to allow
; for toggling whether to autodisplay annotations as one navigates
; through the bookmark list.
;
; Do note that the documentation for function `called-interactively-p'
; discourages its use in favor of eg. '(not (or executing-kbd-macro
; noninteractive))'. See there for details.
;
(defvar bookmark-bmenu-toggle-auto-display-annotations nil
"When not `nil', function `bookmark-bmenu-show-annotation' (by
default, bound to `a`), toggles whether to automatically display
a bookmark's annotation as one navigates through the bookmark
list. Default is `nil'.")

(defun bookmark-bmenu-show-annotation ()
  "Show the annotation for the current bookmark in another window."
  (interactive)
  (when (and (called-interactively-p "any")
             bookmark-bmenu-toggle-auto-display-annotations)
    (if bookmark-bmenu-auto-display-annotations
      (setq bookmark-bmenu-auto-display-annotations nil)
     (setq bookmark-bmenu-auto-display-annotations t)))
  (let ((bookmark (bookmark-bmenu-bookmark)))
    (bookmark-show-annotation bookmark)))
;-------------------------------------------------------------------