>From 573fd67baaf17a5344fe0827641e5edb271dd599 Mon Sep 17 00:00:00 2001
From: Kyle Meyer <address@hidden>
Date: Tue, 2 Dec 2014 01:34:38 -0500
Subject: [PATCH 4/4] org-timer.el: Isolate commands of different timers

* lisp/org-timer.el: Fix timer bugs resulting from crosstalk between
commands for relative and countdown timers.

Several issues were caused by relative timer functions trying to work
with countdown timers.

- When org-timer-start was called with a countdown timer, the modeline
  was updated for the new relative timer, but the countdown timer
  remained scheduled.

- When org-timer-pause-or-continue was called with a countdown timer
  running, the modeline was put in a paused state, but the countdown
  timer remained scheduled.

- When org-timer-stop was called with a countdown timer running, the
  timer was removed from the modeline, but the countdown timer remained
  scheduled.

Another issue was due to a countdown timer function trying to work with
a relative timer.

- When org-timer-set-timer was called with a paused relative timer, the
  relative timer was not reset properly (org-timer-pause-time was still
  non-nil) and the modeline remained in the paused state of the relative
  timer, even though the countdown timer was scheduled with
  run-with-timer.

To prevent all these issues, refuse to execute relative timer commands
if a countdown timer is running, and vice versa.
---
 lisp/org-timer.el | 34 +++++++++++++++++++++++-----------
 1 file changed, 23 insertions(+), 11 deletions(-)

diff --git a/lisp/org-timer.el b/lisp/org-timer.el
index 6cecd7e..147528e 100644
--- a/lisp/org-timer.el
+++ b/lisp/org-timer.el
@@ -93,6 +93,8 @@ (defvar org-timer-done-hook nil
 (defvar org-timer-cancel-hook nil
   "Hook run before countdown timer is canceled.")
 
+(defvar org-timer-timer-is-countdown nil)
+
 ;;;###autoload
 (defun org-timer-start (&optional offset)
   "Set the starting time for the relative timer to now.
@@ -105,8 +107,12 @@ (defun org-timer-start (&optional offset)
 the amount, with the default to make the first timer string in
 the region 0:00:00."
   (interactive "P")
-  (if (equal offset '(16))
-      (call-interactively 'org-timer-change-times-in-region)
+  (cond
+   ((equal offset '(16))
+    (call-interactively 'org-timer-change-times-in-region))
+   (org-timer-timer-is-countdown
+    (user-error "Countdown timer is running.  Cancel first"))
+   (t
     (let (delta def s)
       (if (not offset)
 	  (setq org-timer-start-time (current-time))
@@ -129,7 +135,7 @@ (defun org-timer-start (&optional offset)
       (message "Timer start time set to %s, current value is %s"
 	       (format-time-string "%T" org-timer-start-time)
 	       (org-timer-secs-to-hms (or delta 0)))
-      (run-hooks 'org-timer-start-hook))))
+      (run-hooks 'org-timer-start-hook)))))
 
 (defun org-timer-pause-or-continue (&optional stop)
   "Pause or continue the relative timer.
@@ -137,7 +143,10 @@ (defun org-timer-pause-or-continue (&optional stop)
   (interactive "P")
   (cond
    (stop (org-timer-stop))
-   ((not org-timer-start-time) (error "No timer is running"))
+   (org-timer-timer-is-countdown
+    (user-error "Countdown timer is running"))
+   ((not org-timer-start-time)
+    (user-error "No relative timer is running"))
    (org-timer-pause-time
     ;; timer is paused, continue
     (setq org-timer-start-time
@@ -160,6 +169,8 @@ (defun org-timer-pause-or-continue (&optional stop)
 (defun org-timer-stop ()
   "Stop the relative timer."
   (interactive)
+  (when org-timer-timer-is-countdown
+    (user-error "Countdown timer is running"))
   (run-hooks 'org-timer-stop-hook)
   (setq org-timer-start-time nil
 	org-timer-pause-time nil)
@@ -192,7 +203,6 @@ (defun org-timer-value-string ()
 	  (org-timer-secs-to-hms
 	   (abs (floor (org-timer-seconds))))))
 
-(defvar org-timer-timer-is-countdown nil)
 (defun org-timer-seconds ()
   (if org-timer-timer-is-countdown
       (- (org-float-time org-timer-start-time)
@@ -354,8 +364,8 @@ (defvar org-timer-current-timer nil)
 (defun org-timer-cancel-timer ()
   "Cancel the current timer."
   (interactive)
-  (if (not org-timer-current-timer)
-      (message "No timer to cancel")
+  (if (not org-timer-timer-is-countdown)
+      (message "No countdown timer to cancel")
     (run-hooks 'org-timer-cancel-hook)
     (cancel-timer org-timer-current-timer)
     (setq org-timer-current-timer nil
@@ -402,6 +412,9 @@ (defun org-timer-set-timer (&optional opt)
 minutes in the Effort property, if any.  You can ignore this by
 using three `C-u' prefix arguments."
   (interactive "P")
+  (when (and org-timer-start-time
+	     (not org-timer-timer-is-countdown))
+    (user-error "Relative timer is running.  Stop first"))
   (let* ((effort-minutes (org-get-at-eol 'effort-minutes 1))
 	 (minutes (or (and (not (equal opt '(64)))
 			   effort-minutes
@@ -435,10 +448,9 @@ (defun org-timer-set-timer (&optional opt)
 		       (concat "File:" (file-name-nondirectory (buffer-file-name)))))
 		  (t (error "Not in an Org buffer"))))
 	     timer-set)
-	(if (or (and org-timer-current-timer
-		     (or (equal opt '(16))
-			 (y-or-n-p "Replace current timer? ")))
-		(not org-timer-current-timer))
+	(if (or (not org-timer-current-timer)
+		(or (equal opt '(16))
+		    (y-or-n-p "Replace current countdown timer? ")))
 	    (progn
 	      (require 'org-clock)
 	      (when org-timer-current-timer
-- 
2.1.3