fix(dashboard): tile resize clipping and phantom scrollbars (Issue #97)

Two dashboard tile CSS issues reported after resizing tiles in the
GridStack-based dashboard:

1. Shrinking the Progress tile's height clipped the lower content
   (time grid, filename, buttons) out of the visible area instead of
   making it scale or scroll - #card-progress had no flex layout, so
   its fixed-size children just overflowed silently under the generic
   overflow:auto rule. Applied the same display:flex;flex-direction:
   column pattern already used for #card-camera, with flex-shrink:0
   on the direct children so the container can properly scroll instead
   of hiding content off-screen.

2. Tiles could show a scrollbar even with nothing to scroll, from
   sub-pixel horizontal overflow under the blanket
   overflow-y:auto/overflow-x:hidden rule (was overflow:auto covering
   both axes) - split it so only vertical scroll is offered, which is
   the only axis dashboard content actually needs.

Verified visually via Playwright: resizing the progress tile to
h=2/h=4 no longer clips content, and a fan-card resize with
scrollHeight==clientHeight now shows no scrollbar.

NIGHTLY_CHANGELOG.md

@@ -2,3 +2,7 @@
 
 - Fix: on printers with multiple daisy-chained ACE units and no toolhead buffer (e.g. Kobra S1 with 2 ACE Pro), only the first unit's 4 slots were ever shown on the dashboard or synced to OrcaSlicer — the bridge silently discarded every ACE unit after the first. All units now show up correctly (Issue #95, thanks @hoovercl for the detailed report and logs)
 - Feat: the GCode browser now supports multi-select and bulk delete — click any file's checkbox to enter select mode, use "Select All" to grab everything currently visible (respecting your active search/filter), then delete the selection with one confirmation instead of one-by-one (Issue #94, thanks @Blaim)
+- Fix: **printing via OrcaSlicer "Upload and print" failed (or fed the wrong spool) when a slot below the used filament was empty** — e.g. printing with Filament 4 while slot 3 was empty. The generated AMS slot mapping inserted a placeholder pointing at the physically empty tray, which the printer rejects. Placeholders now point at a loaded tray instead. Printing with all slots full already worked and is unchanged.
+- Fix: manually assigning a filament profile to an ACE slot could crash the MQTT callback (`'list' object has no attribute 'get'`) when the printer rejected the assignment, e.g. for custom-RFID/third-party filament. The bridge now handles the printer's failure response cleanly instead of crashing, and the log now correlates a rejected assignment with the request that triggered it (slot/type/color) so a rejection reason can be diagnosed from bridge logs alone (Issue #100, thanks @Blaim)
+- Fix: **the camera stream could hang forever after a printer reboot** — the printer rotates its stream token on reboot, but the running ffmpeg processes kept reading from the stale, now-silent connection and never noticed. The bridge now detects the URL change and automatically restarts the camera pipeline, ffmpeg itself now times out on a stalled read as a second line of defense, and `/api/camera/stream` now returns a proper 503 instead of hanging if no frame arrives within 5s (Issue #99, thanks @fmontagna for the excellent root-cause analysis and reproduction)
+- Fix: shrinking the Progress dashboard tile below its default height clipped the lower content (time grid, filename, buttons) out of view instead of scaling with it; dashboard tiles in general could show a scrollbar even when there was nothing to scroll. Both fixed (Issue #97, thanks @Blaim)

kobrax_moonraker_bridge.py

@@ -631,7 +631,16 @@ class CameraCache:
         self._fail_count_mjpeg: int = 0
 
     def set_url(self, url: str):
+        # A changed URL means the printer rotated its stream token (typically
+        # after a reboot). Running ffmpeg processes still hold the stale URL
+        # and will never pick it up on their own - they only re-read self._url
+        # at the top of their outer loop, which they never reach while blocked
+        # in a stdout read on the old, now-silent connection. Tear them down;
+        # the next ensure_running() respawns them against the new URL.
+        changed = bool(url and self._url and url != self._url)
         self._url = url
+        if changed:
+            self.reset()
 
     def reset(self):
         """Reset backoff counters and forcefully tear down any running
@@ -679,7 +688,12 @@ class CameraCache:
             self._task_mjpeg = asyncio.create_task(self._run_mjpeg_loop())
 
     def _input_args(self, url: str) -> list[str]:
-        args = ["-fflags", "nobuffer", "-flags", "low_delay"]
+        args = ["-fflags", "nobuffer", "-flags", "low_delay",
+                 # Bail out if the source goes silent. A printer reboot or
+                 # network loss leaves the TCP connection ESTABLISHED with no
+                 # data and no FIN, so a passive stdout read blocks forever
+                 # without this (Issue #99). Value is microseconds.
+                 "-timeout", "10000000"]
         if url.lower().startswith("rtsp://"):
             args += ["-probesize", "32", "-analyzeduration", "0", "-rtsp_transport", "tcp"]
         else:
@@ -989,6 +1003,7 @@ class KobraXBridge:
         except Exception:
             self._visible_vendors = []
         self._last_state: dict = {}
+        self._last_ams_set_request: dict | None = None
         self._state = {
           "nozzle_temp":        0.0,
           "nozzle_target":      0.0,
@@ -1762,6 +1777,14 @@ class KobraXBridge:
         max_idx = max(loaded_map.keys())
         # The printer interprets ams_box_mapping as an ordered list (entry N = TN).
         # Missing slots must be inserted as placeholders, otherwise everything shifts.
+        # A placeholder must NOT reference a physically empty tray: the printer
+        # rejects such an entry even for a tool the GCode never calls (printing
+        # Filament 4 with the slot below it empty fails; all-full works). Point
+        # gap placeholders at a definitely-loaded tray instead of the gap's own
+        # (empty) index.
+        fallback_gidx = max_idx  # highest loaded slot -> loaded + printable
+        fallback_slot = loaded_map[fallback_gidx]
+        fallback_ams = self._slot_to_print_ams_index(fallback_gidx)
         result = []
         for i in range(max_idx + 1):
             if i in loaded_map:
@@ -1776,10 +1799,10 @@ class KobraXBridge:
             else:
                 result.append({
                     "paint_index": i,
-                    "ams_index": self._slot_to_print_ams_index(i),
+                    "ams_index": fallback_ams,
                     "paint_color": [255, 255, 255, 255],
-                    "ams_color": [255, 255, 255, 255],
-                    "material_type": "PLA",
+                    "ams_color": self._slot_color_rgba(fallback_slot),
+                    "material_type": fallback_slot.get("type", "PLA"),
                 })
         return result
 
@@ -1871,10 +1894,21 @@ class KobraXBridge:
         return activity
 
     def _on_multicolor_box(self, payload: dict):
+        if payload.get("state") == "failed":
+            req = getattr(self, "_last_ams_set_request", None)
+            log.warning(
+                f"multiColorBox setInfo rejected by printer: request={req}  raw_response={payload.get('data')}"
+            )
+            self._state["last_ams_set_error"] = True
+            return
         data = payload.get("data") or {}
+        if not isinstance(data, dict):
+            log.warning(f"multiColorBox/report: unexpected data shape: {data!r}")
+            return
         boxes = data.get("multi_color_box") or []
         if not boxes:
             return
+        self._state["last_ams_set_error"] = False
         self._head_tools_model = int(data.get("head_tools_model", self._head_tools_model))
         self._filament_mode = self._detect_filament_mode(boxes, self._head_tools_model)
         self._state["filament_mode"] = self._filament_mode
@@ -4029,6 +4063,11 @@ class KobraXBridge:
             return web.json_response({"error": "color must be [r,g,b]"}, status=400)
         box_id, local_slot = self._global_to_box_slot(index)
         loop = asyncio.get_event_loop()
+        self._state["last_ams_set_error"] = False
+        # Remembered so a later state="failed" report (which carries no slot
+        # info of its own, see _on_multicolor_box) can be logged alongside the
+        # request that triggered it - otherwise the failure is unattributable.
+        self._last_ams_set_request = {"global": index, "box": box_id, "local_slot": local_slot, "type": mat, "color": color}
         # setInfo goes via the web/printer topic (like tempature/set). Verified via
         # Workbench-Vue mqtt_setInfo verifiziert — via slicer/printer/ wurden
         # slot changes are ignored by the printer and overwritten with the old
@@ -4343,6 +4382,16 @@ class KobraXBridge:
         q: asyncio.Queue[bytes] = asyncio.Queue(maxsize=8)
         self.camera_cache.mjpeg_subscribers.add(q)
 
+        # Wait for the first frame BEFORE resp.prepare() - once prepare() sends
+        # the response headers the status is committed to 200, so a stalled
+        # source (Issue #99) must be caught here to actually return a 503
+        # instead of hanging the client forever with no frame ever arriving.
+        try:
+            first_frame = await asyncio.wait_for(q.get(), timeout=5.0)
+        except asyncio.TimeoutError:
+            self.camera_cache.mjpeg_subscribers.discard(q)
+            return web.Response(status=503, text="No frame in cache yet")
+
         boundary = "kobraxframe"
         resp = web.StreamResponse(headers={
             "Content-Type": f"multipart/x-mixed-replace;boundary={boundary}",
@@ -4351,8 +4400,8 @@ class KobraXBridge:
         })
         await resp.prepare(request)
         try:
+            frame = first_frame
             while True:
-                frame = await q.get()
                 header = (
                     f"--{boundary}\r\n"
                     f"Content-Type: image/jpeg\r\n"
@@ -4364,6 +4413,7 @@ class KobraXBridge:
                     break
                 except Exception:
                     break
+                frame = await q.get()
         except Exception as e:
             log.warning(f"Camera stream interrupted: {e}")
         finally:

tests/test_auto_ams_box_mapping_empty_slot.py

@@ -0,0 +1,85 @@
+"""Empty-tray placeholder bug in the OrcaSlicer "upload and print" path.
+
+Real KX1 bug (confirmed 2026-07-22): printing Filament 4 with the slot below it
+EMPTY fails; with all slots full it works. `_start_print` -> `_build_auto_ams_box_mapping`
+inserts a positional placeholder at each gap whose `ams_index` points at the
+gap's own (physically EMPTY) tray. The printer rejects a mapping entry that
+references an empty tray, even for a tool the GCode never calls.
+
+Invariant the fix must hold: EVERY entry's ams_index references a LOADED tray.
+Positional alignment (entry N = TN, from a16062f) must be preserved.
+"""
+import argparse
+import tempfile
+from unittest.mock import MagicMock
+
+from kobrax_moonraker_bridge import KobraXBridge
+
+# Real KX1 AMS state: slot 2 (idx 2) EMPTY, below the used Filament 4 (idx 3).
+AMS_SLOTS = [
+    {"global_index": 0, "box_id": -1, "status": 5, "type": "PLA",      "color": [101, 88, 177]},
+    {"global_index": 1, "box_id": -1, "status": 5, "type": "PLA SILK", "color": [239, 96, 163]},
+    {"global_index": 2, "box_id": -1, "status": 4, "type": "PLA",      "color": [223, 221, 220]},  # EMPTY
+    {"global_index": 3, "box_id": -1, "status": 5, "type": "PLA",      "color": [117, 120, 123]},
+]
+
+
+def _bridge(slots=AMS_SLOTS):
+    c = MagicMock(); c.callbacks = {}; c.connected = False
+    args = argparse.Namespace(
+        printer_ip="", mqtt_port=9883, username="", password="",
+        mode_id="20030", device_id="", host="127.0.0.1", port=7125,
+        data_dir=tempfile.mkdtemp(prefix="kxauto-"),
+    )
+    b = KobraXBridge(c, args=args)
+    b._filament_mode = "toolhead"
+    b._ams_slots = [dict(s) for s in slots]
+    return b
+
+
+def _loaded_ams_indices(b):
+    return {b._slot_to_print_ams_index(int(s["global_index"]))
+            for s in b._ams_slots if s["status"] == 5}
+
+
+def test_no_entry_points_at_an_empty_tray_when_only_used_slot_loaded():
+    """_start_print filters loaded to the used slot only: loaded=[(3, slot3)].
+    Positions 0..2 are placeholders and must NOT reference empty tray idx 2."""
+    b = _bridge()
+    loaded = [(3, b._ams_slots[3])]
+
+    mapping = b._build_auto_ams_box_mapping(loaded_slots=loaded)
+
+    assert [e["paint_index"] for e in mapping] == [0, 1, 2, 3]  # positional alignment kept
+    loaded_ams = _loaded_ams_indices(b)
+    bad = [e for e in mapping if e["ams_index"] not in loaded_ams]
+    assert not bad, f"entries reference an empty/non-loaded tray: {bad}"
+
+
+def test_no_entry_points_at_an_empty_tray_with_gap_in_loaded_set():
+    """All occupied slots mapped (0,1,3 loaded, 2 empty). The placeholder at
+    position 2 must not reference the empty tray idx 2."""
+    b = _bridge()
+    loaded = [(0, b._ams_slots[0]), (1, b._ams_slots[1]), (3, b._ams_slots[3])]
+
+    mapping = b._build_auto_ams_box_mapping(loaded_slots=loaded)
+
+    assert [e["paint_index"] for e in mapping] == [0, 1, 2, 3]
+    loaded_ams = _loaded_ams_indices(b)
+    bad = [e for e in mapping if e["ams_index"] not in loaded_ams]
+    assert not bad, f"entries reference an empty/non-loaded tray: {bad}"
+    # Real loaded slots keep their own ams_index.
+    assert mapping[0]["ams_index"] == 0
+    assert mapping[1]["ams_index"] == 1
+    assert mapping[3]["ams_index"] == 3
+
+
+def test_all_full_is_unchanged():
+    """All slots loaded -> no placeholders, identity mapping (the working case)."""
+    slots = [dict(s, status=5) for s in AMS_SLOTS]
+    b = _bridge(slots)
+    loaded = [(i, b._ams_slots[i]) for i in range(4)]
+
+    mapping = b._build_auto_ams_box_mapping(loaded_slots=loaded)
+
+    assert [e["ams_index"] for e in mapping] == [0, 1, 2, 3]

tests/test_camera_cache_url_rotation.py

@@ -0,0 +1,51 @@
+"""Camera stream hangs forever after printer reboot (Issue #99).
+
+The printer rotates its stream token on reboot, changing the camera URL.
+CameraCache.set_url() used to be a bare assignment - the running ffmpeg loops
+never noticed since they only re-read self._url at the top of their outer
+loop, which they never reach while permanently blocked reading stdout from
+the now-silent, stale-token connection. set_url() must detect the change and
+tear the loops down so the next ensure_running() respawns them against the
+new URL.
+"""
+from kobrax_moonraker_bridge import CameraCache
+
+
+def test_set_url_first_time_does_not_reset():
+    """No prior URL - nothing stale to tear down."""
+    c = CameraCache()
+    calls = []
+    c.reset = lambda: calls.append(True)
+    c.set_url("http://printer/live/tokenA")
+    assert c._url == "http://printer/live/tokenA"
+    assert not calls
+
+
+def test_set_url_same_value_does_not_reset():
+    c = CameraCache()
+    calls = []
+    c.set_url("http://printer/live/tokenA")
+    c.reset = lambda: calls.append(True)
+    c.set_url("http://printer/live/tokenA")
+    assert not calls
+
+
+def test_set_url_changed_triggers_reset():
+    """The actual bug scenario: token rotates after a printer reboot."""
+    c = CameraCache()
+    calls = []
+    c.set_url("http://printer/live/tokenA")
+    c.reset = lambda: calls.append(True)
+    c.set_url("http://printer/live/tokenB")
+    assert c._url == "http://printer/live/tokenB"
+    assert calls == [True]
+
+
+def test_set_url_empty_to_value_does_not_reset():
+    """Startup case: no URL known yet, first status push sets it - nothing
+    running to tear down."""
+    c = CameraCache()
+    calls = []
+    c.reset = lambda: calls.append(True)
+    c.set_url("http://printer/live/tokenA")
+    assert not calls

tests/test_multicolor_box_failed_state.py

@@ -0,0 +1,81 @@
+"""AttributeError crash on multiColorBox/report failure (Issue #100).
+
+Real KX2-Pro bug: manually assigning a filament profile to an ACE slot
+(custom-RFID / third-party filament) gets rejected by the printer. Instead of
+echoing the normal success shape, the printer replies with `state: "failed"`
+and `data` as a 2-element LIST (`["multi_color_box", [...]]`) instead of the
+usual dict (`{"multi_color_box": [...]}`). `_on_multicolor_box` called
+`data.get(...)` unconditionally, crashing with
+`AttributeError: 'list' object has no attribute 'get'` and silently dropping
+the report (including the slot-state update it would otherwise have done).
+"""
+import argparse
+import tempfile
+from unittest.mock import MagicMock
+
+from kobrax_moonraker_bridge import KobraXBridge
+
+# Exact failure payload from the Issue #100 log.
+FAILED_PAYLOAD = {
+    "state": "failed",
+    "data": ["multi_color_box", [{"filaments": {"id": 2}, "id": 0}]],
+}
+
+SUCCESS_PAYLOAD = {
+    "state": "success",
+    "data": {
+        "head_tools_model": 1,
+        "multi_color_box": [
+            {"id": -1, "slots": []},
+            {
+                "id": 0,
+                "slots": [
+                    {"index": 0, "type": "PLA", "color": [0, 156, 189], "status": 5},
+                ],
+            },
+        ],
+    },
+}
+
+
+def _bridge():
+    c = MagicMock(); c.callbacks = {}; c.connected = False
+    args = argparse.Namespace(
+        printer_ip="", mqtt_port=9883, username="", password="",
+        mode_id="20030", device_id="", host="127.0.0.1", port=7125,
+        data_dir=tempfile.mkdtemp(prefix="kxmcb-"),
+    )
+    return KobraXBridge(c, args=args)
+
+
+def test_failed_state_does_not_crash():
+    b = _bridge()
+    b._on_multicolor_box(FAILED_PAYLOAD)  # must not raise
+    assert b._state["last_ams_set_error"] is True
+
+
+def test_success_after_failure_clears_error_flag():
+    b = _bridge()
+    b._on_multicolor_box(FAILED_PAYLOAD)
+    assert b._state["last_ams_set_error"] is True
+    b._on_multicolor_box(SUCCESS_PAYLOAD)
+    assert b._state["last_ams_set_error"] is False
+
+
+def test_non_dict_data_without_failed_state_does_not_crash():
+    """Defensive guard: any future non-dict `data` shape must not crash,
+    even if the printer doesn't set state="failed" for it."""
+    b = _bridge()
+    b._on_multicolor_box({"state": "success", "data": ["multi_color_box", []]})
+
+
+def test_failed_report_is_logged_with_the_triggering_request(caplog):
+    """The failure payload alone carries no slot/type/color info - the log
+    must correlate it with the setInfo request that triggered it, otherwise
+    the failure reason can't be diagnosed from bridge logs alone."""
+    import logging
+    b = _bridge()
+    b._last_ams_set_request = {"global": 6, "box": 0, "local_slot": 3, "type": "PLA", "color": [33, 39, 33]}
+    with caplog.at_level(logging.WARNING):
+        b._on_multicolor_box(FAILED_PAYLOAD)
+    assert any("global" in r.message and "6" in r.message for r in caplog.records)

web/themes/default/style.css

@@ -108,7 +108,7 @@ main{flex:1;overflow-y:auto;padding:20px}
    GridStack's resize-handle hit area and drag listeners. */
 /* Doc pattern: the card fills its cell; content scrolls if the user resizes
    the cell smaller than the content needs. */
-.grid-stack-item-content>.card{width:100%;height:100%;margin:0;overflow:auto;box-sizing:border-box}
+.grid-stack-item-content>.card{width:100%;height:100%;margin:0;overflow-y:auto;overflow-x:hidden;box-sizing:border-box}
 /* .card:hover{transform:translateY(-1px)} creates a new containing block right
    as the user starts dragging, throwing off GridStack's position math. Kill
    the hover transform for dashboard cards specifically. */
@@ -164,6 +164,11 @@ main{flex:1;overflow-y:auto;padding:20px}
 .cam-toggle:hover{background:rgba(0,0,0,.7)}
 
 /* ── PROGRESS ── */
+/* Same pattern as #card-camera above: without this, shrinking the tile's
+   height just clips the lower content (time-grid/filename/buttons) outside
+   the visible area instead of making it scrollable (Issue #97). */
+.grid-stack-item-content>#card-progress{display:flex;flex-direction:column;min-height:0}
+.grid-stack-item-content>#card-progress>*{flex-shrink:0}
 .hero-info{display:flex;flex-direction:column;gap:12px}
 .pct-big{font-size:52px;font-weight:700;line-height:1;color:var(--txt)}
 .pct-big small{font-size:20px;font-weight:400;color:var(--txt2)}