2 files changed, 22 insertions, 55 deletions
diff --git a/module/output/color.scm b/module/output/color.scm
new file mode 100644
index 00000000..123d0ba2
--- /dev/null
+++ b/module/output/color.scm
@@ -0,0 +1,22 @@
+(define-module (output color)
+  )
+
+;; Returns a color with good contrast to the given background color.
+;; https://stackoverflow.com/questions/1855884/determine-font-color-based-on-background-color/1855903#1855903
+(define-public (calculate-fg-color c)
+  (catch #t
+    (lambda ()
+      (define (str->num c n) (string->number (substring/shared c n (+ n 2)) 16))
+      ;; (format (current-error-port) "COLOR = ~s~%" c)
+      (let ((r (str->num c 1))
+            (g (str->num c 3))
+            (b (str->num c 5)))
+        (if (< 1/2 (/ (+ (* 0.299 r)
+                         (* 0.587 g)
+                         (* 0.114 b))
+                      #xFF))
+            "#000000" "#FFFFFF")))
+    (lambda args
+      (format (current-error-port) "Error calculating foreground color?~%~s~%" args)
+      "#FF0000"
+      )))
diff --git a/module/output/vdir.scm b/module/output/vdir.scm
deleted file mode 100644
index 2541f0f9..00000000
--- a/module/output/vdir.scm
+++ /dev/null
@@ -1,55 +0,0 @@
-;;; Commentary:
-;;; Module for writing components to the vdir storage format.
-;;; Currently also has some cases for "big" icalendar files,
-;;; but those are currently unsupported.
-
-;;; TODO generalize save-event and remove-event into a general interface,
-;;; which different database backends can implement. Actually, do that for all
-;;; loading and writing.
-
-;;; Code:
-
-(define-module (output vdir)
-  :use-module (util)
-  :use-module (vcomponent ical output)
-  :use-module (vcomponent)
-  :use-module ((util io) :select (with-atomic-output-to-file))
-  )
-
-
-(define / file-name-separator-string)
-
-(define-public (save-event event)
-  (define calendar (parent event))
-  (case (prop calendar '-X-HNH-SOURCETYPE)
-    [(file)
-     (error "Importing into direct calendar files not supported")]
-
-    [(vdir)
-     (let* ((uid (or (prop event 'UID) (uuidgen))))
-       (set! (prop event 'UID) uid
-             ;; TODO use existing filename if present?
-             (prop event '-X-HNH-FILENAME) (string-append
-                                            (prop calendar '-X-HNH-DIRECTORY)
-                                            / uid ".ics"))
-       (with-atomic-output-to-file (prop event '-X-HNH-FILENAME)
-        (lambda () (print-components-with-fake-parent (list event))))
-       uid)]
-
-    [else
-     (error "Source of calendar unknown, aborting.")
-     ]))
-
-
-(define-public (remove-event event)
-  (define calendar (parent event))
-  (case (prop calendar '-X-HNH-SOURCETYPE)
-    [(file)
-     (error "Removing events from large files unsupported")]
-
-    [(vdir)
-     (delete-file (prop event '-X-HNH-FILENAME))]
-
-    [else
-     (error "Source of calendar unknown, aborting.")
-     ]))