[oni-org] Experiment with using more contexts to filter tasks

Instead of adding a lot of tags and adding a lot of agendas filtering on them
I'm experimenting with using org-edna to make certain contexts a dependency of a
task to filter them out of my todo list.

Current contexts I'm experimenting with are:

- ‘day-of-week?’ to filter out tasks that I can only do on certain days.

- ‘night-time?’ to filter out anything that I can't do in the evening. Usually
  having to do with contacting others.

- ‘business-hours?’ to filter out anything that is outside of a certain
  timezone's “business hours”, defined by me as anywhere between 9am and 6pm.

oni-org/oni-org.el

@@ -4,7 +4,7 @@
 
 ;; Author: Tom Willemse <tom@ryuslash.org>
 ;; Keywords: local
-;; Version: 2023.0409.214302
+;; Version: 2023.0411.202312
 ;; Package-Requires: (oni-yasnippet oni-alert oni-hydra org org-contrib org-bullets org-edna diminish all-the-icons olivetti form-feed org-pretty-table)
 
 ;; This program is free software; you can redistribute it and/or modify
@@ -600,16 +600,7 @@ also move point to the start of the heading."
 (setq org-agenda-dim-blocked-tasks 'invisible)
 
 (setq org-agenda-custom-commands
-      `(("t" . "Things to do")
+      `(("t" "Todo" tags-todo "TODO=\"TODO\"-CATEGORY=\"project\"+(SCHEDULED<\"<tomorrow>\"|TODO=\"TODO\"-CATEGORY=\"project\"+SCHEDULED=\"\")")
-        ("tt" "Todo at this computer" tags-todo ,(format "@%s|@computer|@emacs/TODO" (system-name))
-         ((org-overriding-columns-format "%TODO %46ITEM %1BLOCKED %Effort")))
-        ("tf" "Fun things to do" tags-todo "+fun")
-        ;; ("r" "Reading list" tags-todo "TODO=\"READ\"+SCHEDULED=\"\"-Effort=\"\""
-        ;;  ((org-overriding-columns-format "%8CATEGORY %ITEM %3EFFORT")
-        ;;   (org-agenda-sorting-strategy '(priority-down effort-up))
-        ;;   (org-agenda-prefix-format " (%3e) %i %-12:c")))
-        ;; ("R" "Reading list (requires estimating)" tags-todo
-        ;; "TODO=\"READ\"+Effort=\"\"")
         ("r" . "Reading")
         ("rc" "Casual reading" tags-todo "TODO=\"READ\"+casual")
         ("rn" "Noteworthy reading" tags-todo "TODO=\"READ\"+note")
@@ -776,6 +767,26 @@ After running it once remove it from `org-capture-after-finalize-hook'."
     (org-goto-first-child)
     (list (point-marker))))
 
+(defun org-edna-condition/day-of-week? (neg weekday)
+  (let ((condition (not (= (string-to-number (format-time-string "%u")) weekday))))
+    (when (xor condition neg)
+      "Not the right day.")))
+
+(defun org-edna-condition/night-time? (neg)
+  "A condition for ‘org-edna’ see if it's what I consider nighttime."
+  (let* ((hour (nth 2 (decode-time)))
+         (condition (or (> hour 20)
+                        (< hour 8))))
+    (when (xor condition neg)
+      "Too late!")))
+
+(defun org-edna-condition/business-hours? (neg timezone)
+  "A condition for ‘org-edna’ to see if it's during regular business hours."
+  (let* ((hour (nth 2 (decode-time nil timezone)))
+         (condition (> 9 hour 18)))
+    (when (xor condition neg)
+      (format "Outside of business hours in %s!" timezone))))
+
 ;;; Refile
 
 (defun oni-org-refile-to-top ()