feat(readers): default EPUB and PDF to a dark/sepia/light reading cycle

nov-mode's reading cycle opened on sepia and ran sepia, dark, light. I reordered it to dark, sepia, light and made a fresh EPUB open dark.

pdf-view only had a binary midnight toggle. I added a matching palette layer: a fresh PDF opens dark, and c cycles dark, sepia, light, none (C selects by name, M also cycles). Each palette is a foreground/background pair fed to pdf-view-midnight-minor-mode, so sepia and light are that same duotone with warmer and lighter colors. The pdf colors mirror the nov palettes so EPUBs and PDFs read alike.

Pure name-to-colors and cycle logic are unit-tested. The live render needs a manual check.

1 files changed, 38 insertions, 0 deletions

diff --git a/tests/test-nov-reading--config-defaults.el b/tests/test-nov-reading--config-defaults.el
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+++ b/tests/test-nov-reading--config-defaults.el
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+;;; test-nov-reading--config-defaults.el --- nov reading default/order tests -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Asserts the shipped reading-view defaults: a fresh EPUB opens dark, and the
+;; `c' cycle runs dark -> sepia -> light -> none -> back.  The pure-logic file
+;; test-nov-reading--palette.el covers the cycle mechanics on fixtures; this file
+;; pins the real `cj/nov-reading-palettes' / `cj/nov-reading-default-palette'
+;; values so a reorder can't silently drift the default or the cycle order.
+
+;;; Code:
+
+(require 'ert)
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'nov-reading)
+
+(declare-function cj/nov--next-reading-palette "nov-reading" (current names))
+(defvar cj/nov-reading-palettes)
+(defvar cj/nov-reading-default-palette)
+
+(ert-deftest test-nov-reading-config-default-is-dark ()
+  "Normal: a fresh nov buffer opens on the dark palette."
+  (should (equal cj/nov-reading-default-palette "dark")))
+
+(ert-deftest test-nov-reading-config-order-is-dark-sepia-light ()
+  "Normal: the shipped palette order is dark, then sepia, then light."
+  (should (equal (mapcar #'car cj/nov-reading-palettes)
+                 '("dark" "sepia" "light"))))
+
+(ert-deftest test-nov-reading-config-cycle-from-default ()
+  "Normal: cycling from the default advances dark -> sepia -> light -> none -> dark."
+  (let ((names (mapcar #'car cj/nov-reading-palettes)))
+    (should (equal (cj/nov--next-reading-palette "dark" names) "sepia"))
+    (should (equal (cj/nov--next-reading-palette "sepia" names) "light"))
+    (should-not (cj/nov--next-reading-palette "light" names))
+    (should (equal (cj/nov--next-reading-palette nil names) "dark"))))
+
+(provide 'test-nov-reading--config-defaults)
+;;; test-nov-reading--config-defaults.el ends here