build: read colours from rendered theme.txt

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 41 insertions, 0 deletions

diff --git a/build b/build
index 73b5823..9097679 100755
--- a/build
+++ b/build
@@ -11,11 +11,39 @@ current wallpaper next to theme.txt. Everything is staged in a temporary
 directory and swapped in at the end, so a failed run leaves the previous
 dist/udt/ untouched. Never touches /boot: root copies dist/udt/ there.
 """
+import re
 import struct
 import sys
 import zlib
+from pathlib import Path
 
 PNG_SIG = b"\x89PNG\r\n\x1a\n"
+REPO = Path(__file__).resolve().parent
+PLACEHOLDERS = {f"@{r}@" for r in (
+    "SCHEME", "BG", "BG_ALT", "BG_DEEP", "SURFACE", "FG", "FG_DIM", "FG_FAINT", "ACCENT")}
+# file name: (fc-match pattern, size, the name grub-mkfont records and theme.txt uses)
+FONTS = {
+    "noto-sans-regular-24.pf2": ("Noto Sans:regular", 24, "Noto Sans Regular 24"),
+    "noto-sans-bold-32.pf2": ("Noto Sans:bold", 32, "Noto Sans Bold 32"),
+    "inconsolata-18.pf2": ("Inconsolata Nerd Font Mono", 18,
+                           "Inconsolata Nerd Font Mono Regular 18"),
+}
+
+
+def die(msg):
+    sys.exit(f"build: {msg}")
+
+
+def read_colours(text):
+    """The colours on the '# udt:' line, as RGB tuples, from a rendered theme."""
+    left = sorted(set(re.findall(r"@[A-Z_]+@", text)))
+    if left:
+        die(f"theme.txt still has placeholders {' '.join(left)}; rerun udt-palette")
+    m = re.search(r"^# udt: (.+)$", text, re.M)
+    if not m:
+        die("theme.txt has no '# udt:' colour line")
+    return {k: tuple(bytes.fromhex(v.lstrip("#")))
+            for k, v in (kv.split("=") for kv in m.group(1).split())}
 
 
 def chunk(tag, data):
@@ -58,6 +86,19 @@ def unpng(data):
 def selftest():
     w, h, px = unpng(png(3, 2, (0x12, 0x34, 0x56, 0xd9)))
     assert (w, h, px) == (3, 2, {(0x12, 0x34, 0x56, 0xd9)}), (w, h, px)
+    good = "# udt: bg_alt=#1e2030 accent=#b7bdf8\ncolor = \"#cad3f5\"\n"
+    assert read_colours(good) == {"bg_alt": (0x1e, 0x20, 0x30), "accent": (0xb7, 0xbd, 0xf8)}
+    for bad in (good + 'color = "@FG@"\n', 'color = "#cad3f5"\n'):
+        try:
+            read_colours(bad)
+        except SystemExit:
+            pass
+        else:
+            raise AssertionError(f"accepted: {bad!r}")
+    tpl = (REPO / "theme.txt.in").read_text()
+    assert set(re.findall(r"@[A-Z_]+@", tpl)) <= PLACEHOLDERS, "template token udt does not fill"
+    for _, _, name in FONTS.values():
+        assert f'"{name}"' in tpl, f"template does not use font {name}"
     print("selftest ok")