+;;; Header narrowing courtesy of Hideyuki Shirai.
+(defun wl-message-header-narrowing ()
+ "Narrowing headers."
+ (unless (eq this-command 'wl-summary-redisplay-all-header)
+ (save-excursion
+ (save-restriction
+ (goto-char (point-min))
+ (if (re-search-forward "^$" nil t)
+ (beginning-of-line)
+ (goto-char (point-max)))
+ (narrow-to-region (point-min) (point))
+ (let ((fields wl-message-header-narrowing-fields))
+ (while fields
+ (wl-message-header-narrowing-1 (concat "^" (car fields) ":"))
+ (setq fields (cdr fields))))))))
+
+(defvar wl-message-header-narrowing-map (make-sparse-keymap))
+(define-key wl-message-header-narrowing-map [mouse-2]
+ 'wl-message-header-narrowing-again-at-mouse)
+
+(defvar wl-message-header-narrowing-widen-map (make-sparse-keymap))
+(define-key wl-message-header-narrowing-widen-map [mouse-2]
+ 'wl-message-header-narrowing-widen-at-mouse)
+
+(defun wl-message-header-narrowing-again-at-mouse (event)
+ (interactive "e")
+ (save-window-excursion
+ (save-excursion
+ (mouse-set-point event)
+ (wl-message-header-narrowing))))
+
+(defun wl-message-header-narrowing-1 (hregexp)
+ (let ((case-fold-search t)
+ ov start end)
+ (goto-char (point-min))
+ (while (re-search-forward hregexp nil t)
+ (setq start (match-beginning 0))
+ (forward-line 1)
+ (setq end (progn (while (looking-at "^[ \t]") (forward-line))
+ (forward-line -1)
+ (line-end-position)))
+ (if (<= (count-lines start end) wl-message-header-narrowing-lines)
+ (forward-line 1)
+ (goto-char start)
+ (forward-line (1- wl-message-header-narrowing-lines))
+ (end-of-line)
+ (setq start (point))
+ (unless (eq (get-char-property start 'invisible)
+ 'wl-message-header-narrowing)
+ (setq ov (or
+ (let ((ovs (overlays-at start))
+ ov)
+ (while (and ovs (not (overlayp ov)))
+ (if (overlay-get (car ovs)
+ 'wl-message-header-narrowing)
+ (setq ov (car ovs)))
+ (setq ovs (cdr ovs)))
+ ov)
+ (make-overlay start end)))
+ (overlay-put ov 'wl-message-header-narrowing t)
+ (overlay-put ov 'evaporate t)
+ (overlay-put ov 'invisible 'wl-message-header-narrowing)
+ (overlay-put ov 'after-string
+ wl-message-header-narrowing-string))))))
+
+(defun wl-message-header-narrowing-widen-at-mouse (event)
+ (interactive "e")
+ (save-selected-window
+ (select-window (posn-window (event-start event)))
+ (let* ((win (selected-window))
+ (wpos (window-start win))
+ (pos (mouse-set-point event))
+ (ovs (overlays-in (1- pos) (1+ pos))) ;; Uum...
+ ov)
+ (while (and ovs (not (overlayp ov)))
+ (when (overlay-get (car ovs) 'wl-message-header-narrowing)
+ (setq ov (car ovs)))
+ (setq ovs (cdr ovs)))
+ (when (overlayp ov)
+ (overlay-put ov 'face 'wl-message-header-narrowing-face)
+ (overlay-put ov 'local-map wl-message-header-narrowing-map)
+ (overlay-put ov 'invisible nil)
+ (overlay-put ov 'after-string nil))
+ (set-window-start win wpos))))
+
+(defun wl-message-header-narrowing-setup ()
+ (when (boundp 'line-move-ignore-invisible)
+ (set (make-local-variable 'line-move-ignore-invisible) t))
+ (set-text-properties 0 (length wl-message-header-narrowing-string)
+ `(face
+ wl-message-header-narrowing-face
+ keymap
+ ,wl-message-header-narrowing-widen-map)
+ wl-message-header-narrowing-string))
+
+(defun wl-message-header-narrowing-toggle ()
+ "Toggle header narrowing."
+ (interactive)
+ (when wl-message-use-header-narrowing
+ (save-excursion
+ (goto-char (point-min))
+ (if (re-search-forward "^$" nil t)
+ (beginning-of-line)
+ (goto-char (point-max)))
+ (let ((ovs (overlays-in (point-min) (point)))
+ ov hn-ovs)
+ (while (setq ov (car ovs))
+ (when (overlay-get ov 'wl-message-header-narrowing)
+ (setq hn-ovs (cons ov hn-ovs)))
+ (setq ovs (cdr ovs)))
+ (if hn-ovs
+ (while hn-ovs
+ (delete-overlay (car hn-ovs))
+ (setq hn-ovs (cdr hn-ovs)))
+ (wl-message-header-narrowing))))))
+