feat: derive washer/dryer/dishwasher cycle list from supportedOptions when editCourseList is empty

Some DA_WM_TP1/TP2-class boards populate /wm/editcourse/vs/0 without ever
filling in editCourseList itself (issue #1), so the Cycle select never gets
created even though the device clearly has one (confirmed via SmartThings
app screenshots and a currently-selected course).

/course/vs/0's own x.com.samsung.da.supportedOptions turns out to already
carry the course list, just undocumented: a 1-hex-nibble header followed by
one fixed-width record per course, self-indexed by a course-code first byte
rather than positional like editCourseList. Confirmed against six
independent real-world dumps pulled from open and closed GitHub issues.

cycle_options() now falls back to deriving this when editCourseList is
empty, gated on two checks: the derived codes must all be distinct, and
must include whatever course is currently selected. Larger multiples of
the true record width trivially re-pass both checks too (they're just a
sparser sampling of the same table), so the smallest passing width wins
rather than requiring one unambiguous match.

Also fires on the washer_flexwash fixture, newly creating a Cycle select
there -- unconfirmed against any ground truth for that device (a different,
older board generation with no editCourseList and no screenshots to check
against), flagged for follow-up discussion rather than silently accepted.

custom_components/localthings/registry/capabilities/laundry.py

@@ -157,6 +157,11 @@ BUZZER_SOUND = Capability(
 # washer.py's course comment has the byte-level evidence for why the options[]
 # MostUsed_* entry is *not* a trustworthy second source.
 #
+# Some boards populate /wm/editcourse/vs/0 without ever filling in
+# editCourseList itself (issue #1) -- cycle_options() falls back to deriving
+# the same list from /course/vs/0's own supportedOptions in that case; see
+# _course_codes_from_supported_options for the byte-level evidence.
+#
 # Shared verbatim by washer, dishwasher, and dryer -- all DA_WM_-family boards
 # expose the same /course/vs/0 options contract.
 # ---------------------------------------------------------------------------
@@ -176,7 +181,10 @@ def parse_edit_course_list(raw):
 
 def cycle_options(resources):
     rep = resources.get('/wm/editcourse/vs/0') or {}
-    return parse_edit_course_list(rep.get('x.com.samsung.da.editCourseList'))
+    codes = parse_edit_course_list(rep.get('x.com.samsung.da.editCourseList'))
+    if codes:
+        return codes
+    return _course_codes_from_supported_options(resources.get('/course/vs/0') or {})
 
 
 def option_value(options, prefix):
@@ -187,6 +195,61 @@ def option_value(options, prefix):
     return None
 
 
+def _course_codes_from_supported_options(course_rep):
+    """Fallback for an empty/missing editCourseList: derive the selectable
+    course list from /course/vs/0's own x.com.samsung.da.supportedOptions
+    instead (issue #1: some DA_WM_TP1/TP2-class boards populate the
+    /wm/editcourse/vs/0 href but never fill in editCourseList itself).
+
+    supportedOptions is a 1-hex-nibble header followed by one fixed-width
+    record per selectable course, self-indexed rather than positional --
+    the first byte of every record is that course's own hex code, just in
+    the firmware's own internal order, not editCourseList's. Confirmed
+    against six independent real-world washer/dryer/dishwasher dumps: every
+    one divides evenly into `header + N * K bytes` with fully unique first
+    bytes across all N records, at the record's true byte width. (What the
+    rest of each record encodes is still unconfirmed -- this only uses the
+    course-code byte.)
+
+    Two guards, deliberately conservative rather than guessing further: the
+    derived codes must (a) all be distinct -- a real course table, not
+    noise -- and (b) include whatever course is currently selected
+    (x.com.samsung.da.options' Course_<code> token), which must always be a
+    member of its own device's valid list. If no split satisfies both, this
+    returns [] rather than guess.
+
+    Among splits that satisfy both, the *smallest* passing K wins rather
+    than requiring a single unambiguous one: any exact multiple of the true
+    K (e.g. 2x or 7x its byte width) trivially re-passes both checks too --
+    it's just a sparser sampling of the same valid table, every entry of
+    which is still a real course code carried over from the finer split --
+    so a larger match is never independent evidence of a different table,
+    only redundant confirmation of the smaller one.
+    """
+    raw = course_rep.get('x.com.samsung.da.supportedOptions')
+    hexstr = raw[0] if isinstance(raw, list) and raw else raw
+    if not isinstance(hexstr, str) or len(hexstr) < 3:
+        return []
+    body = hexstr[1:]
+    if len(body) % 2:
+        return []
+    total_bytes = len(body) // 2
+    current = option_value(course_rep.get('x.com.samsung.da.options'), 'Course')
+    for k in range(1, total_bytes + 1):
+        if total_bytes % k:
+            continue
+        n = total_bytes // k
+        if n < 2:
+            continue
+        firsts = [body[i * k * 2:i * k * 2 + 2] for i in range(n)]
+        if len(set(firsts)) != n:
+            continue
+        if current is not None and current not in firsts:
+            continue
+        return firsts
+    return []
+
+
 def replace_in_options(options, prefix, new_value):
     return [f"{prefix}_{new_value}" if isinstance(o, str) and o.startswith(prefix + '_') else o
             for o in options]

tests/fixtures/golden/washer_flexwash.json

@@ -2,6 +2,7 @@
   "state_keys": [
     "alarm_code",
     "child_lock",
+    "cycle",
     "cycle_active",
     "delay_start_hours",
     "detergent_low",

tests/test_laundry_capabilities.py

@@ -35,6 +35,81 @@ class TestCourseHelpers:
         assert laundry.option_value(opts, 'Missing') is None
 
 
+class TestCourseCodesFromSupportedOptions:
+    """cycle_options()'s fallback for boards that populate
+    /wm/editcourse/vs/0 without ever filling in editCourseList itself
+    (issue #1) -- derives the course list from /course/vs/0's own
+    supportedOptions instead."""
+
+    # Real dump from issue #1 (DA_WM_TP1_21_COMMON, WW5000C): a 1-hex-nibble
+    # header followed by 14 self-indexed 7-byte-per-course records. '1C' (the
+    # first record) is confirmed as "Eco 40-60" both by this device's own
+    # currently-selected course matching the SmartThings app screenshot's
+    # checked item, and by six other independent devices' already-shipped
+    # translations agreeing on the same code -> name mapping.
+    _REAL_SUPPORTED_OPTIONS = (
+        '31C8410923FA67F1B847E923FA67F25843E933FA57F20857E943FA67F'
+        '088000913FA67F7485209204A5208780009000A00006841E930FA30F'
+        '7F841E920FA30F65841E943FA57F8F8102923FA57F96841E920FA37F'
+        '34841E923FA67FA0811E933FA33F'
+    )
+
+    def test_derives_codes_when_edit_course_list_is_empty(self):
+        resources = {
+            '/wm/editcourse/vs/0': {'x.com.samsung.da.editCourseList': ''},
+            '/course/vs/0': {
+                'x.com.samsung.da.options': ['Course_1C'],
+                'x.com.samsung.da.supportedOptions': [self._REAL_SUPPORTED_OPTIONS],
+            },
+        }
+        assert laundry.cycle_options(resources) == [
+            '1C', '1B', '25', '20', '08', '74', '87', '06',
+            '7F', '65', '8F', '96', '34', 'A0',
+        ]
+
+    def test_edit_course_list_still_takes_priority(self):
+        """A live editCourseList wins even with supportedOptions present --
+        no reason to prefer a derived list over the authoritative one."""
+        resources = {
+            '/wm/editcourse/vs/0': {'x.com.samsung.da.editCourseList': 'EditCourseList_651C'},
+            '/course/vs/0': {
+                'x.com.samsung.da.options': ['Course_1C'],
+                'x.com.samsung.da.supportedOptions': [self._REAL_SUPPORTED_OPTIONS],
+            },
+        }
+        assert laundry.cycle_options(resources) == ['65', '1C']
+
+    def test_rejects_a_table_missing_the_current_course(self):
+        """The device's own currently-selected course must be a member of
+        its derived list -- a mismatch means the guess is wrong, not that
+        the device selected something outside its own supported set."""
+        resources = {
+            '/course/vs/0': {
+                'x.com.samsung.da.options': ['Course_FF'],
+                'x.com.samsung.da.supportedOptions': [self._REAL_SUPPORTED_OPTIONS],
+            },
+        }
+        assert laundry.cycle_options(resources) == []
+
+    def test_smallest_passing_split_wins_over_its_own_multiples(self):
+        """K=2 and K=4 both trivially re-pass the same two checks here --
+        each is just a sparser sampling of the true, smaller K=1 table (its
+        first bytes are a subset of K=1's, so uniqueness and "contains the
+        current course" carry over for free) -- but K=1 is the real, most
+        specific table and must be the one returned."""
+        resources = {
+            '/course/vs/0': {
+                'x.com.samsung.da.options': ['Course_AA'],
+                'x.com.samsung.da.supportedOptions': ['0AABBCCDD'],
+            },
+        }
+        assert laundry.cycle_options(resources) == ['AA', 'BB', 'CC', 'DD']
+
+    def test_empty_without_supported_options_or_course_href(self):
+        assert laundry.cycle_options({}) == []
+        assert laundry.cycle_options({'/course/vs/0': {}}) == []
+
+
 class TestCycleSelect:
     def test_builds_labelled_cycle_select(self):
         desc = laundry.cycle_select(translation_key='dryer_cycle', icon='mdi:tumble-dryer')