chore: bump version to 0.1.10 [skip ci]

The printer chart API was issuing one extra SELECT per row per field that the
serializer read but .only() omitted. nozzle_temp_left/nozzle_target_temp_left
were added to the serialization loop without being added to _METRICS_API_FIELDS,
so a single-day request ran 5,507 queries and took 34s; the UI's default 48h
range took 87s. Against a remote Postgres this is pure round-trip latency.

- Add the two left-nozzle fields to _METRICS_API_FIELDS.
- Always apply both time bounds in PrinterDataAPIView. Missing or partial date
  params previously left the range open, so a bare API call scanned the whole
  metrics table.
- Give PrinterDashboardView the same treatment the API already had: .only(),
  sampling to _MAX_CHART_POINTS, and a targeted snapshot fetch. It also
  evaluated its queryset twice, because .last() on an unevaluated queryset
  issues its own query plus its own prefetch.
- Extract sample_metrics() and fetch_snapshots_by_metric() for reuse.

Printer shares the infrastructure_device table with a host project's other
devices and had no category field, so Printer.objects.filter(is_active=True)
could return a NAS. Add a category field and a category-scoped default manager,
keeping all_objects as the unfiltered base manager so related descriptors still
resolve every row. Migration 0009 creates the column in standalone deployments
and skips the DDL where the host project already owns it.

Measured: API 87s -> 0.67s, dashboard 3.4s -> 0.9s. Query counts are now
independent of row count, asserted by tests.

Dockerfile

@@ -22,19 +22,20 @@ RUN pip install --no-cache-dir bambu-lab-cloud-api --no-deps && \
         (d / 'INSTALLER').write_text('pip\n'); \
         (d / 'RECORD').write_text('')"
 
-# Install project and remaining dependencies (pip sees opencv-python already satisfied)
+# Install standalone dependencies first — cached unless pyproject.toml changes
 COPY pyproject.toml .
 RUN pip install --no-cache-dir ".[standalone,mcp]"
 
-# Copy application code
+# Copy full source and install the local package (no-deps: already installed above)
 COPY . .
+RUN pip install --no-cache-dir --no-deps .
 
 # Create data directory for SQLite
 RUN mkdir -p /app/data
 
-# Collect static files
+# Collect static files from the locally installed package
 ENV DJANGO_SETTINGS_MODULE=standalone.settings
-RUN python standalone/manage.py collectstatic --noinput 2>/dev/null || true
+RUN python standalone/manage.py collectstatic --noinput
 
 # Supervisor config to run both web and collector
 COPY docker/supervisord.conf /etc/supervisor/conf.d/supervisord.conf

bambu_run/admin.py

@@ -1,5 +1,5 @@
 from django.contrib import admin
-from .models import Printer, PrinterMetrics, Filament, FilamentType, FilamentSnapshot, PrintJob, FilamentUsage, BambuCloudTask
+from .models import Printer, PrinterMetrics, Filament, FilamentType, FilamentSnapshot, PrintJob, FilamentUsage, BambuCloudTask, Hotend, HotendSnapshot
 
 
 @admin.register(Printer)
@@ -107,6 +107,21 @@ class FilamentUsageAdmin(admin.ModelAdmin):
     readonly_fields = ('consumed_percent', 'consumed_grams')
 
 
+@admin.register(Hotend)
+class HotendAdmin(admin.ModelAdmin):
+    list_display = ('printer', 'serial_number', 'nozzle_type', 'is_toolhead', 'slot_number', 'used_time_seconds', 'wear_percent', 'last_seen_at')
+    list_filter = ('printer', 'is_toolhead', 'nozzle_type')
+    search_fields = ('serial_number',)
+    readonly_fields = ('last_seen_at', 'created_at')
+
+
+@admin.register(HotendSnapshot)
+class HotendSnapshotAdmin(admin.ModelAdmin):
+    list_display = ('printer_metric', 'hotend', 'raw_id', 'used_time_seconds', 'wear_percent', 'timestamp')
+    list_filter = ('hotend',)
+    readonly_fields = ('printer_metric', 'hotend', 'raw_id', 'used_time_seconds', 'wear_percent', 'stat', 'timestamp')
+
+
 @admin.register(BambuCloudTask)
 class BambuCloudTaskAdmin(admin.ModelAdmin):
     list_display = ('task_id', 'design_title', 'plate_title', 'device_serial', 'cloud_status', 'weight_grams', 'cloud_start_time', 'synced_at')

bambu_run/management/commands/bambu_collector.py

@@ -554,6 +554,8 @@ class Command(BaseCommand):
                 printer_metric=printer_metric,
                 filament=filament,
                 tray_id=tray_id,
+                ams_unit_id=unit_id_int,
+                ams_type=tray_data.get('ams_type', '') or '',
                 slot_name=tray_data.get('slot'),
                 type=tray_data.get('type'),
                 sub_type=tray_data.get('sub_type'),
@@ -569,6 +571,38 @@ class Command(BaseCommand):
                 match_method=match_method
             )
 
+    def _update_hotends(self, printer, printer_metric, hotends_data):
+        from bambu_run.models import Hotend, HotendSnapshot
+
+        for h in hotends_data:
+            if h.get("is_empty"):
+                continue
+
+            hotend, _ = Hotend.objects.update_or_create(
+                printer=printer,
+                serial_number=h.get("serial_number"),
+                defaults={
+                    "raw_id": h.get("raw_id", 0),
+                    "nozzle_type": h.get("nozzle_type", ""),
+                    "diameter": self._to_decimal(h.get("diameter")),
+                    "slot_number": h.get("slot_number"),
+                    "is_toolhead": bool(h.get("is_toolhead")),
+                    "last_filament_profile_id": h.get("fila_id", ""),
+                    "last_color": h.get("color") or "",
+                    "used_time_seconds": h.get("used_time_seconds", 0),
+                    "wear_percent": h.get("wear_percent", 0),
+                },
+            )
+
+            HotendSnapshot.objects.create(
+                printer_metric=printer_metric,
+                hotend=hotend,
+                raw_id=h.get("raw_id", 0),
+                used_time_seconds=h.get("used_time_seconds", 0),
+                wear_percent=h.get("wear_percent", 0),
+                stat=h.get("stat"),
+            )
+
     def _track_print_job(self, session, metric, snapshot):
         from bambu_run.models import PrintJob
 
@@ -641,31 +675,40 @@ class Command(BaseCommand):
         elif not session.trays_used:
             logger.warning(f"No trays tracked for job {job.project_name}, skipping filament usage")
         else:
+            # A bare tray_id (from `tray_now`) doesn't identify which physical AMS
+            # unit was active when multiple units share the same slot numbering —
+            # so create one usage row per (unit, tray) that had a tracked filament
+            # loaded at job start, rather than guessing a single "correct" unit.
+            created_usages = []
             for tray_id in session.trays_used:
-                start_snap = start_metric.filament_snapshots.filter(
+                start_snaps = start_metric.filament_snapshots.filter(
                     tray_id=tray_id, filament__isnull=False
-                ).first()
-                if not start_snap:
-                    continue
-
-                end_snap = metric.filament_snapshots.filter(
-                    filament=start_snap.filament, tray_id=tray_id
-                ).first()
-
-                usage = FilamentUsage.objects.create(
-                    print_job=job,
-                    filament=start_snap.filament,
-                    tray_id=tray_id,
-                    starting_percent=start_snap.remain_percent or 100,
-                    ending_percent=end_snap.remain_percent if end_snap else None,
-                    is_primary=(len(session.trays_used) == 1),
                 )
-                usage.calculate_consumed()
+                for start_snap in start_snaps:
+                    end_snap = metric.filament_snapshots.filter(
+                        filament=start_snap.filament,
+                        tray_id=tray_id,
+                        ams_unit_id=start_snap.ams_unit_id,
+                    ).first()
+
+                    usage = FilamentUsage.objects.create(
+                        print_job=job,
+                        filament=start_snap.filament,
+                        tray_id=tray_id,
+                        ams_unit_id=start_snap.ams_unit_id,
+                        starting_percent=start_snap.remain_percent or 100,
+                        ending_percent=end_snap.remain_percent if end_snap else None,
+                    )
+                    usage.calculate_consumed()
+                    created_usages.append(usage)
+
+            for usage in created_usages:
+                usage.is_primary = len(created_usages) == 1
                 usage.save()
 
                 if self.verbose:
                     logger.debug(
-                        f"Filament usage for {start_snap.filament} (tray {tray_id}): "
+                        f"Filament usage for {usage.filament} (unit {usage.ams_unit_id}, tray {usage.tray_id}): "
                         f"{usage.starting_percent}% -> {usage.ending_percent}%, consumed {usage.consumed_percent}%"
                     )
 
@@ -746,12 +789,17 @@ class Command(BaseCommand):
                     external_spool=snapshot.get("external_spool", {}),
                     lights_report=snapshot.get("lights_report", []),
                     vortek_raw=snapshot.get("vortek_raw", {}),
+                    nozzle_info=snapshot.get("hotends", []),
                 )
 
                 filaments_data = snapshot.get('filaments', [])
                 if filaments_data:
                     self._create_filament_snapshots(metric, filaments_data, snapshot)
 
+                hotends_data = snapshot.get('hotends', [])
+                if hotends_data:
+                    self._update_hotends(session.printer, metric, hotends_data)
+
                 self._track_print_job(session, metric, snapshot)
 
                 session.success_count += 1

bambu_run/migrations/0006_alter_filamentsnapshot_options_and_more.py

@@ -0,0 +1,63 @@
+# Generated by Django 5.2.8 on 2026-06-20 12:40
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("bambu_run", "0005_printermetrics_vortek_raw"),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name="filamentsnapshot",
+            options={
+                "ordering": ["printer_metric", "ams_unit_id", "tray_id"],
+                "verbose_name": "Filament Snapshot",
+                "verbose_name_plural": "Filament Snapshots",
+            },
+        ),
+        migrations.AddField(
+            model_name="filamentsnapshot",
+            name="ams_type",
+            field=models.CharField(
+                blank=True,
+                choices=[
+                    ("AMS", "AMS"),
+                    ("AMS 2 Pro", "AMS 2 Pro"),
+                    ("AMS HT", "AMS HT"),
+                ],
+                default="",
+                help_text="Type of the AMS unit this tray belongs to (AMS / AMS 2 Pro / AMS HT)",
+                max_length=32,
+            ),
+        ),
+        migrations.AddField(
+            model_name="filamentsnapshot",
+            name="ams_unit_id",
+            field=models.PositiveSmallIntegerField(
+                blank=True,
+                db_index=True,
+                help_text="Which physical AMS unit this tray belongs to (matches MQTT ams[i].id; 128 = AMS HT)",
+                null=True,
+            ),
+        ),
+        migrations.AddField(
+            model_name="filamentusage",
+            name="ams_unit_id",
+            field=models.PositiveSmallIntegerField(
+                blank=True,
+                db_index=True,
+                help_text="Which physical AMS unit the slot belongs to (matches MQTT ams[i].id; 128 = AMS HT)",
+                null=True,
+            ),
+        ),
+        migrations.AddIndex(
+            model_name="filamentsnapshot",
+            index=models.Index(
+                fields=["printer_metric", "ams_unit_id", "tray_id"],
+                name="infrastruct_printer_2ad168_idx",
+            ),
+        ),
+    ]

bambu_run/migrations/0007_hotend_hotendsnapshot.py

@@ -0,0 +1,172 @@
+# Generated by Django 5.2.8 on 2026-06-20 14:07
+
+import django.db.models.deletion
+import django.utils.timezone
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("bambu_run", "0006_alter_filamentsnapshot_options_and_more"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="Hotend",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("serial_number", models.CharField(db_index=True, max_length=100)),
+                (
+                    "nozzle_type",
+                    models.CharField(blank=True, default="", max_length=50),
+                ),
+                (
+                    "diameter",
+                    models.DecimalField(
+                        blank=True, decimal_places=2, max_digits=3, null=True
+                    ),
+                ),
+                (
+                    "raw_id",
+                    models.PositiveSmallIntegerField(
+                        help_text="Last-seen MQTT device.nozzle.info[].id"
+                    ),
+                ),
+                (
+                    "slot_number",
+                    models.PositiveSmallIntegerField(
+                        blank=True,
+                        help_text="Rack bay 1-6, derived from raw_id 16-21. Null if currently unknown (e.g. mounted on toolhead and id reports as the 0 sentinel).",
+                        null=True,
+                    ),
+                ),
+                (
+                    "is_toolhead",
+                    models.BooleanField(
+                        default=False,
+                        help_text="True if currently mounted on the toolhead under normal polling (raw_id == 0).",
+                    ),
+                ),
+                (
+                    "last_filament_profile_id",
+                    models.CharField(
+                        blank=True,
+                        default="",
+                        help_text="Bambu material profile id of the filament last loaded (MQTT fila_id, e.g. 'GFA01')",
+                        max_length=20,
+                    ),
+                ),
+                (
+                    "last_color",
+                    models.CharField(
+                        blank=True,
+                        default="",
+                        help_text="6-char hex of the filament last loaded (MQTT color_m, alpha stripped)",
+                        max_length=6,
+                    ),
+                ),
+                ("used_time_seconds", models.PositiveIntegerField(default=0)),
+                (
+                    "wear_percent",
+                    models.DecimalField(
+                        decimal_places=2,
+                        default=0,
+                        help_text="MQTT wear (0-128 scale) converted to a 0-100 percent",
+                        max_digits=5,
+                    ),
+                ),
+                ("last_seen_at", models.DateTimeField(auto_now=True)),
+                ("created_at", models.DateTimeField(auto_now_add=True)),
+                (
+                    "printer",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="hotends",
+                        to="bambu_run.printer",
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Hotend",
+                "verbose_name_plural": "Hotends",
+                "db_table": "infrastructure_hotend",
+                "ordering": ["printer", "-is_toolhead", "slot_number", "serial_number"],
+                "unique_together": {("printer", "serial_number")},
+            },
+        ),
+        migrations.CreateModel(
+            name="HotendSnapshot",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("raw_id", models.PositiveSmallIntegerField()),
+                ("used_time_seconds", models.PositiveIntegerField(default=0)),
+                (
+                    "wear_percent",
+                    models.DecimalField(decimal_places=2, default=0, max_digits=5),
+                ),
+                (
+                    "stat",
+                    models.IntegerField(
+                        blank=True,
+                        help_text="Raw MQTT status code for this hotend",
+                        null=True,
+                    ),
+                ),
+                (
+                    "timestamp",
+                    models.DateTimeField(
+                        db_index=True, default=django.utils.timezone.now
+                    ),
+                ),
+                (
+                    "hotend",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="snapshots",
+                        to="bambu_run.hotend",
+                    ),
+                ),
+                (
+                    "printer_metric",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="hotend_snapshots",
+                        to="bambu_run.printermetrics",
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Hotend Snapshot",
+                "verbose_name_plural": "Hotend Snapshots",
+                "db_table": "infrastructure_hotend_snapshot",
+                "ordering": ["printer_metric", "hotend"],
+                "indexes": [
+                    models.Index(
+                        fields=["printer_metric", "hotend"],
+                        name="infrastruct_printer_b528aa_idx",
+                    ),
+                    models.Index(
+                        fields=["hotend", "-timestamp"],
+                        name="infrastruct_hotend__691f7e_idx",
+                    ),
+                ],
+            },
+        ),
+    ]

bambu_run/migrations/0008_printermetrics_nozzle_info.py

@@ -0,0 +1,22 @@
+# Generated by Django 5.2.8 on 2026-06-20 14:22
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("bambu_run", "0007_hotend_hotendsnapshot"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="printermetrics",
+            name="nozzle_info",
+            field=models.JSONField(
+                blank=True,
+                default=list,
+                help_text="Parsed per-poll nozzle/hotend info list",
+            ),
+        ),
+    ]

bambu_run/migrations/0009_printer_category.py

@@ -0,0 +1,77 @@
+"""Add Printer.category so printer queries can be scoped away from other devices.
+
+`infrastructure_device` is shared with host projects. In a standalone Bambu-Run
+deployment bambu_run owns the table and the column must be created here. In a
+host project like RAE the table was created by that project's own app and
+already carries a `category` column, so creating it again would fail.
+`AddFieldIfMissing` introspects the table and only emits DDL when needed; the
+model state is updated either way.
+"""
+
+import django.db.models.manager
+from django.db import migrations, models
+
+
+class AddFieldIfMissing(migrations.AddField):
+    """AddField that is a no-op at the database level if the column exists."""
+
+    def database_forwards(self, app_label, schema_editor, from_state, to_state):
+        model = to_state.apps.get_model(app_label, self.model_name)
+        with schema_editor.connection.cursor() as cursor:
+            existing = {
+                column.name
+                for column in schema_editor.connection.introspection.get_table_description(
+                    cursor, model._meta.db_table
+                )
+            }
+        if self.name in existing:
+            return
+        super().database_forwards(app_label, schema_editor, from_state, to_state)
+
+    def database_backwards(self, app_label, schema_editor, from_state, to_state):
+        """Reverse the model state only, never the column.
+
+        In a host project the column belongs to that project's own app — dropping
+        it on reverse would break the host's device model. Leaving an unused
+        column behind in a standalone rollback is the harmless side of this trade.
+        """
+        return
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("bambu_run", "0008_printermetrics_nozzle_info"),
+    ]
+
+    operations = [
+        AddFieldIfMissing(
+            model_name="printer",
+            name="category",
+            field=models.CharField(
+                default="threed_printer",
+                help_text=(
+                    "Device category. Always 'threed_printer' for printers — present "
+                    "because host projects may share this table with other device types."
+                ),
+                max_length=50,
+            ),
+        ),
+        migrations.AlterModelOptions(
+            name="printer",
+            options={
+                "base_manager_name": "all_objects",
+                "default_manager_name": "objects",
+                "ordering": ["name"],
+                "verbose_name": "Printer",
+                "verbose_name_plural": "Printers",
+            },
+        ),
+        migrations.AlterModelManagers(
+            name="printer",
+            managers=[
+                ("all_objects", django.db.models.manager.Manager()),
+                ("objects", django.db.models.manager.Manager()),
+            ],
+        ),
+    ]

bambu_run/models.py

@@ -8,7 +8,8 @@ from django.utils import timezone
 AMS_INFO_TO_TYPE = {
     "1001": "AMS",
     "1003": "AMS 2 Pro",
-    "2104": "AMS HT",
+    "1104": "AMS HT",   # observed on production H2C (last 4 of info code 11001104)
+    "2104": "AMS HT",   # observed in dev capture (last 4 of info code 11002104)
 }
 
 AMS_TYPE_CHOICES = [
@@ -21,19 +22,44 @@ AMS_TYPE_CHOICES = [
 def ams_type_from_info(info_code) -> str:
     """Resolve an AMS unit's `info` model code to a human label.
 
-    The HT unit reports its `id` with the 0x80 bit set (e.g. 128) — when the info
+    Real MQTT `info` codes are 8 characters (e.g. "10001003") with the type encoded
-    code is unknown, that bit is a reasonable secondary hint for HT identification.
+    in the last 4 digits — confirmed against a live H2C with AMS 2 Pro / AMS / AMS HT.
+    Fall back to an exact match for the bare 4-digit form in case other firmware
+    reports it short.
     """
-    if info_code is None:
+    if not info_code:
         return ""
-    return AMS_INFO_TO_TYPE.get(str(info_code), "")
+    code = str(info_code)
+    return AMS_INFO_TO_TYPE.get(code[-4:], "") or AMS_INFO_TO_TYPE.get(code, "")
+
+
+class PrinterManager(models.Manager):
+    """Default manager — scopes every query to actual 3D printers.
+
+    `Printer` shares the `infrastructure_device` table with a host project's other
+    device rows (RAE stores its NAS, routers and cameras there too). Without this
+    scoping, `Printer.objects.filter(is_active=True).first()` can return a NAS.
+    """
+
+    def get_queryset(self):
+        return super().get_queryset().filter(category=Printer.CATEGORY_3D_PRINTER)
 
 
 class Printer(models.Model):
     """Represents a Bambu Lab 3D printer device"""
 
+    CATEGORY_3D_PRINTER = "threed_printer"
+
     name = models.CharField(max_length=200, help_text="Friendly device name")
     model = models.CharField(max_length=100, help_text="Device model (e.g., X1C, P1S)")
+    category = models.CharField(
+        max_length=50,
+        default=CATEGORY_3D_PRINTER,
+        help_text=(
+            "Device category. Always 'threed_printer' for printers — present because "
+            "host projects may share this table with other device types."
+        ),
+    )
     manufacturer = models.CharField(
         max_length=100, default="Bambu Lab", help_text="e.g., Bambu Lab"
     )
@@ -48,11 +74,19 @@ class Printer(models.Model):
     first_seen = models.DateTimeField(auto_now_add=True)
     last_updated = models.DateTimeField(auto_now=True)
 
+    # `all_objects` is declared first so it serves as the base manager for related
+    # descriptors (PrinterMetrics.device etc.) — those must never filter, or rows
+    # attached to a mis-categorised device become unreachable.
+    all_objects = models.Manager()
+    objects = PrinterManager()
+
     class Meta:
         db_table = "infrastructure_device"
         verbose_name = "Printer"
         verbose_name_plural = "Printers"
         ordering = ["name"]
+        base_manager_name = "all_objects"
+        default_manager_name = "objects"
 
     def __str__(self):
         return f"{self.name} ({self.model})"
@@ -239,6 +273,15 @@ class PrinterMetrics(models.Model):
         default=dict, blank=True, help_text="Raw print.device MQTT payload (Vortek rack groundwork)"
     )
 
+    # Parsed device.nozzle.info[] from this poll, one dict per entry (mirrors
+    # HotendInfo.to_dict()). Includes induction-chip hotends *and* non-inductive
+    # nozzle positions (e.g. H2C's fixed left nozzle) that have no stable serial
+    # number to key a Hotend registry row on — kept here so the dashboard can show
+    # their readable type/diameter without claiming an identity/history we don't have.
+    nozzle_info = models.JSONField(
+        default=list, blank=True, help_text="Parsed per-poll nozzle/hotend info list"
+    )
+
     class Meta:
         db_table = "infrastructure_printer_metrics"
         verbose_name = "Printer Metric"
@@ -498,6 +541,15 @@ class FilamentSnapshot(models.Model):
         max_length=20, null=True, blank=True,
         help_text="Slot identifier like A00-W1"
     )
+    ams_unit_id = models.PositiveSmallIntegerField(
+        null=True, blank=True, db_index=True,
+        help_text="Which physical AMS unit this tray belongs to (matches MQTT ams[i].id; 128 = AMS HT)"
+    )
+    ams_type = models.CharField(
+        max_length=32, blank=True, default="",
+        choices=AMS_TYPE_CHOICES,
+        help_text="Type of the AMS unit this tray belongs to (AMS / AMS 2 Pro / AMS HT)"
+    )
 
     type = models.CharField(max_length=50, null=True, blank=True)
     sub_type = models.CharField(
@@ -545,9 +597,10 @@ class FilamentSnapshot(models.Model):
         db_table = "infrastructure_filament_snapshot"
         verbose_name = "Filament Snapshot"
         verbose_name_plural = "Filament Snapshots"
-        ordering = ['printer_metric', 'tray_id']
+        ordering = ['printer_metric', 'ams_unit_id', 'tray_id']
         indexes = [
             models.Index(fields=['printer_metric', 'tray_id']),
+            models.Index(fields=['printer_metric', 'ams_unit_id', 'tray_id']),
             models.Index(fields=['filament']),
         ]
 
@@ -686,6 +739,10 @@ class FilamentUsage(models.Model):
     )
 
     tray_id = models.IntegerField(help_text="Which AMS slot was used")
+    ams_unit_id = models.PositiveSmallIntegerField(
+        null=True, blank=True, db_index=True,
+        help_text="Which physical AMS unit the slot belongs to (matches MQTT ams[i].id; 128 = AMS HT)"
+    )
 
     starting_percent = models.IntegerField(help_text="Filament remaining % at job start")
     ending_percent = models.IntegerField(
@@ -723,3 +780,108 @@ class FilamentUsage(models.Model):
                 self.consumed_grams = int(
                     self.filament.initial_weight_grams * (self.consumed_percent / 100.0)
                 )
+
+
+class Hotend(models.Model):
+    """Registry of individual Vortek hotends, keyed by serial number.
+
+    A Vortek rack holds up to 6 swappable hotends (bays, MQTT `id` 16-21) plus
+    1 mounted on the toolhead at a time (MQTT `id` 0). `raw_id` reflects whichever
+    address was last seen on the wire for this hotend; `slot_number` is only set
+    when that address falls in the 16-21 rack-bay range — confirmed by watching
+    a "Read All" MQTT capture reassign a toolhead-mounted hotend's id from 0 to
+    its true bay id.
+    """
+
+    printer = models.ForeignKey(
+        'Printer', on_delete=models.CASCADE, related_name='hotends'
+    )
+    serial_number = models.CharField(max_length=100, db_index=True)
+
+    nozzle_type = models.CharField(max_length=50, blank=True, default="")
+    diameter = models.DecimalField(
+        max_digits=3, decimal_places=2, null=True, blank=True
+    )
+
+    raw_id = models.PositiveSmallIntegerField(
+        help_text="Last-seen MQTT device.nozzle.info[].id"
+    )
+    slot_number = models.PositiveSmallIntegerField(
+        null=True, blank=True,
+        help_text="Rack bay 1-6, derived from raw_id 16-21. Null if currently unknown (e.g. mounted on toolhead and id reports as the 0 sentinel)."
+    )
+    is_toolhead = models.BooleanField(
+        default=False,
+        help_text="True if currently mounted on the toolhead under normal polling (raw_id == 0)."
+    )
+
+    last_filament_profile_id = models.CharField(
+        max_length=20, blank=True, default="",
+        help_text="Bambu material profile id of the filament last loaded (MQTT fila_id, e.g. 'GFA01')"
+    )
+    last_color = models.CharField(
+        max_length=6, blank=True, default="",
+        help_text="6-char hex of the filament last loaded (MQTT color_m, alpha stripped)"
+    )
+
+    used_time_seconds = models.PositiveIntegerField(default=0)
+    wear_percent = models.DecimalField(
+        max_digits=5, decimal_places=2, default=0,
+        help_text="MQTT wear (0-128 scale) converted to a 0-100 percent"
+    )
+
+    last_seen_at = models.DateTimeField(auto_now=True)
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        db_table = "infrastructure_hotend"
+        verbose_name = "Hotend"
+        verbose_name_plural = "Hotends"
+        ordering = ['printer', '-is_toolhead', 'slot_number', 'serial_number']
+        unique_together = [['printer', 'serial_number']]
+
+    def __str__(self):
+        location = "Toolhead" if self.is_toolhead else (
+            f"Slot {self.slot_number}" if self.slot_number else "Rack"
+        )
+        return f"{self.serial_number} ({location})"
+
+    @property
+    def used_time_display(self) -> str:
+        hours, remainder = divmod(self.used_time_seconds, 3600)
+        minutes = remainder // 60
+        return f"{hours}h {minutes}m" if hours else f"{minutes}m"
+
+
+class HotendSnapshot(models.Model):
+    """Point-in-time reading of a Hotend, one row per collector poll."""
+
+    printer_metric = models.ForeignKey(
+        'PrinterMetrics', on_delete=models.CASCADE,
+        related_name='hotend_snapshots'
+    )
+    hotend = models.ForeignKey(
+        'Hotend', on_delete=models.CASCADE,
+        related_name='snapshots'
+    )
+
+    raw_id = models.PositiveSmallIntegerField()
+    used_time_seconds = models.PositiveIntegerField(default=0)
+    wear_percent = models.DecimalField(max_digits=5, decimal_places=2, default=0)
+    stat = models.IntegerField(
+        null=True, blank=True, help_text="Raw MQTT status code for this hotend"
+    )
+    timestamp = models.DateTimeField(default=timezone.now, db_index=True)
+
+    class Meta:
+        db_table = "infrastructure_hotend_snapshot"
+        verbose_name = "Hotend Snapshot"
+        verbose_name_plural = "Hotend Snapshots"
+        ordering = ['printer_metric', 'hotend']
+        indexes = [
+            models.Index(fields=['printer_metric', 'hotend']),
+            models.Index(fields=['hotend', '-timestamp']),
+        ]
+
+    def __str__(self):
+        return f"{self.hotend.serial_number} @ {self.timestamp.strftime('%Y-%m-%d %H:%M:%S')}"

bambu_run/mqtt_client.py

@@ -296,6 +296,73 @@ class AMSState:
         return loaded
 
 
+@dataclass
+class HotendInfo:
+    """A single hotend reported in `device.nozzle.info[]` (Vortek rack).
+
+    `raw_id` semantics (confirmed by watching a live "Read All" MQTT capture):
+    0 = currently mounted on the (swappable) toolhead — the sentinel hides the
+    true bay address until "Read All" resolves it; 1 = the fixed left nozzle on
+    dual-nozzle printers (no RFID chip, always reports sn="N/A"); 16-21 = rack
+    bay address, slot_number = raw_id - 15 (1-6).
+    """
+    raw_id: int = 0
+    serial_number: str = ""
+    nozzle_type: str = ""
+    diameter: float = 0.4
+    fila_id: str = ""
+    color: Optional[str] = None
+    used_time_seconds: int = 0
+    wear_percent: float = 0.0
+    stat: int = 0
+
+    @classmethod
+    def from_dict(cls, data: Dict[str, Any]) -> "HotendInfo":
+        from .utils import strip_color_padding
+
+        return cls(
+            raw_id=int(data.get("id", 0)),
+            serial_number=data.get("sn", ""),
+            nozzle_type=data.get("type", ""),
+            diameter=float(data.get("diameter", 0.4)),
+            fila_id=data.get("fila_id", ""),
+            color=strip_color_padding(data.get("color_m")),
+            used_time_seconds=int(data.get("p_t", 0)),
+            wear_percent=round(float(data.get("wear", 0.0)) / 128.0 * 100, 2),
+            stat=int(data.get("stat", 0)),
+        )
+
+    @property
+    def is_toolhead(self) -> bool:
+        return self.raw_id == 0
+
+    @property
+    def is_empty(self) -> bool:
+        return self.serial_number in ("", "N/A")
+
+    @property
+    def slot_number(self) -> Optional[int]:
+        if 16 <= self.raw_id <= 21:
+            return self.raw_id - 15
+        return None
+
+    def to_dict(self) -> Dict[str, Any]:
+        return {
+            "raw_id": self.raw_id,
+            "serial_number": self.serial_number,
+            "nozzle_type": self.nozzle_type,
+            "diameter": self.diameter,
+            "fila_id": self.fila_id,
+            "color": self.color,
+            "used_time_seconds": self.used_time_seconds,
+            "wear_percent": self.wear_percent,
+            "stat": self.stat,
+            "is_toolhead": self.is_toolhead,
+            "is_empty": self.is_empty,
+            "slot_number": self.slot_number,
+        }
+
+
 @dataclass
 class PrinterState:
     """Complete printer state parsed from MQTT data"""
@@ -388,6 +455,9 @@ class PrinterState:
     # External spool (virtual tray)
     vt_tray: Optional[Dict[str, Any]] = None
 
+    # Vortek hotend rack (device.nozzle.info[])
+    hotends: List[HotendInfo] = field(default_factory=list)
+
     # Raw data for any additional fields
     _raw_data: Dict[str, Any] = field(default_factory=dict, repr=False)
 
@@ -431,6 +501,12 @@ class PrinterState:
                 nozzle_target_temp_left = float((t >> 16) & 0xFFFF)
                 nozzle_temp_left = float(t & 0xFFFF)
 
+        # Vortek hotend rack: device.nozzle.info[] — one entry per hotend.
+        hotends = [
+            HotendInfo.from_dict(h)
+            for h in (device.get("nozzle") or {}).get("info") or []
+        ]
+
         return cls(
             timestamp=timestamp,
             sequence_id=str(print_data.get("sequence_id", "")),
@@ -487,6 +563,7 @@ class PrinterState:
             gcode_file_prepare_percent=str(print_data.get("gcode_file_prepare_percent", "")),
             lifecycle=print_data.get("lifecycle", ""),
             vt_tray=print_data.get("vt_tray"),
+            hotends=hotends,
             _raw_data=data,
         )
 
@@ -533,6 +610,7 @@ class PrinterState:
             # hotends + 1 fixed left nozzle) isn't fully modeled yet — stash everything
             # here so no data is lost once the real Vortek MQTT schema is confirmed.
             "vortek_raw": self._raw_data.get("print", {}).get("device", {}),
+            "hotends": [h.to_dict() for h in self.hotends],
             "hms": self.hms,
             "stg_cur": self.stg_cur,
             "lights_report": self.lights_report,

bambu_run/static/bambu_run/css/dashboard.css

@@ -64,3 +64,78 @@
     opacity: 0.9;
     color: rgba(255, 255, 255, 0.9);
 }
+
+/* AMS unit type colors — CSS variables so RAE/standalone can override per theme */
+:root {
+    --ams-badge-ams: #6c757d;
+    --ams-badge-ams-2-pro: #0d6efd;
+    --ams-badge-ams-ht: #fd7e14;
+    --ams-group-border-color: rgba(0, 0, 0, 0.15);
+}
+
+[data-coreui-theme="dark"] {
+    --ams-group-border-color: rgba(255, 255, 255, 0.2);
+}
+
+.ams-badge-ams {
+    background-color: var(--ams-badge-ams);
+    color: #fff;
+}
+
+.ams-badge-ams-2-pro {
+    background-color: var(--ams-badge-ams-2-pro);
+    color: #fff;
+}
+
+.ams-badge-ams-ht {
+    background-color: var(--ams-badge-ams-ht);
+    color: #fff;
+}
+
+.ams-filter-pills {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 0.5rem;
+}
+
+.ams-filter-pill {
+    border-radius: 50rem;
+    padding: 0.25rem 0.9rem;
+    font-size: 0.85rem;
+    border: 1px solid var(--ams-group-border-color);
+    background-color: transparent;
+    opacity: 0.6;
+}
+
+.ams-filter-pill.active {
+    opacity: 1;
+    font-weight: 600;
+    border-color: currentColor;
+}
+
+/* Grouped AMS unit panels — Bootstrap row/col handles sizing;
+   multi-slot units (AMS/AMS 2 Pro) are col-12, single-slot (AMS HT) are col-lg-3. */
+.ams-group {
+    border-radius: 0.5rem;
+    padding: 0.75rem;
+    border: 1px solid var(--ams-group-border-color);
+}
+
+.ams-badge-bg-ams {
+    background-color: color-mix(in srgb, var(--ams-badge-ams) 8%, transparent);
+    border-left: 3px solid var(--ams-badge-ams);
+}
+
+.ams-badge-bg-ams-2-pro {
+    background-color: color-mix(in srgb, var(--ams-badge-ams-2-pro) 8%, transparent);
+    border-left: 3px solid var(--ams-badge-ams-2-pro);
+}
+
+.ams-badge-bg-ams-ht {
+    background-color: color-mix(in srgb, var(--ams-badge-ams-ht) 8%, transparent);
+    border-left: 3px solid var(--ams-badge-ams-ht);
+}
+
+.ams-badge-bg- {
+    border-left: 3px solid var(--ams-group-border-color);
+}

bambu_run/static/bambu_run/js/printer_charts.js

@@ -625,8 +625,23 @@ function createFilamentDatasets(filamentTimeline, timestamps) {
         data: filamentTimeline[key]
     }));
 
-    // Sort by tray_id (numeric first, External last), then by start_idx (chronological)
+    // Distinct (non-null/undefined) AMS units present in this timeline — used to decide
+    // whether labels need an AMS unit prefix (avoid noise for the common single-AMS case).
+    const distinctUnits = new Set(
+        filamentEntries
+            .map(e => e.data.ams_unit_id)
+            .filter(uid => uid !== null && uid !== undefined)
+    );
+    const showUnitPrefix = distinctUnits.size > 1;
+
+    // Sort by AMS unit, then tray_id (numeric first, External last), then by start_idx
     filamentEntries.sort((a, b) => {
+        const unitA = a.data.ams_unit_id ?? -1;
+        const unitB = b.data.ams_unit_id ?? -1;
+        if (unitA !== unitB) {
+            return unitA - unitB;
+        }
+
         const trayA = a.data.tray_id;
         const trayB = b.data.tray_id;
 
@@ -659,6 +674,10 @@ function createFilamentDatasets(filamentTimeline, timestamps) {
             displayLabel = `Tray ${filament.tray_id} (${filament.type})`;
         }
 
+        if (showUnitPrefix && filament.ams_type) {
+            displayLabel = `${filament.ams_type} · ${displayLabel}`;
+        }
+
         // Add brand if it's different from type (avoid redundancy)
         if (filament.brand && filament.brand !== filament.type && filament.brand !== 'External') {
             displayLabel += ` - ${filament.brand}`;

bambu_run/templates/bambu_run/printer_dashboard.html

@@ -37,32 +37,38 @@
     <!-- Summary Cards Row -->
     <div class="row g-3 mb-4">
         {% if stats.is_dual_nozzle %}
-        <!-- Right Nozzle (dual-nozzle printers, e.g. H2C) -->
+        <!-- Left Nozzle (dual-nozzle printers, e.g. H2C) -->
         <div class="col-12 col-md-6 col-lg-3">
-            <div class="card infra-card-warning">
+            <div class="card infra-card-warning h-100">
                 <div class="card-body">
                     <div class="d-flex justify-content-between align-items-start">
                         <div>
-                            <div class="stat-label">Right Nozzle</div>
+                            <div class="stat-label d-flex align-items-center gap-1">
-                            <div class="stat-value">{{ stats.nozzle_temp|floatformat:1 }}&deg;C</div>
+                                <svg class="icon" style="width: 1.25rem; height: 1.25rem;"><use href="{% static 'bambu_run/vendors/coreui-icons-free.svg' %}#cil-arrow-thick-left"></use></svg>
-                            <div class="text-muted small">target {{ stats.nozzle_target_temp|floatformat:0 }}&deg;C
+                                Left Nozzle
-                                {% if stats.nozzle_type %}· {{ stats.nozzle_type }}{% endif %}</div>
+                            </div>
+                            <div class="stat-value">{{ stats.nozzle_temp_left|floatformat:1 }}&deg;C</div>
+                            <div class="text-muted small">target {{ stats.nozzle_target_temp_left|floatformat:0 }}&deg;C
+                                {% if stats.nozzle_type_left %}· Nozzle {{ stats.nozzle_type_left }}{% endif %}</div>
                         </div>
                         <i class="bi bi-thermometer-high" style="font-size: 2rem; opacity: 0.3;"></i>
                     </div>
                 </div>
             </div>
         </div>
-        <!-- Left Nozzle -->
+        <!-- Right Nozzle -->
         <div class="col-12 col-md-6 col-lg-3">
-            <div class="card infra-card-warning">
+            <div class="card infra-card-warning h-100">
                 <div class="card-body">
                     <div class="d-flex justify-content-between align-items-start">
                         <div>
-                            <div class="stat-label">Left Nozzle</div>
+                            <div class="stat-label d-flex align-items-center gap-1">
-                            <div class="stat-value">{{ stats.nozzle_temp_left|floatformat:1 }}&deg;C</div>
+                                Right Nozzle
-                            <div class="text-muted small">target {{ stats.nozzle_target_temp_left|floatformat:0 }}&deg;C
+                                <svg class="icon" style="width: 1.25rem; height: 1.25rem;"><use href="{% static 'bambu_run/vendors/coreui-icons-free.svg' %}#cil-arrow-thick-right"></use></svg>
-                                {% if stats.nozzle_type_left %}· {{ stats.nozzle_type_left }}{% endif %}</div>
+                            </div>
+                            <div class="stat-value">{{ stats.nozzle_temp|floatformat:1 }}&deg;C</div>
+                            <div class="text-muted small">target {{ stats.nozzle_target_temp|floatformat:0 }}&deg;C
+                                {% if stats.nozzle_type %}· Nozzle {{ stats.nozzle_type }}{% endif %}</div>
                         </div>
                         <i class="bi bi-thermometer-high" style="font-size: 2rem; opacity: 0.3;"></i>
                     </div>
@@ -72,7 +78,7 @@
         {% else %}
         <!-- Nozzle Temperature Card (single-nozzle printers) -->
         <div class="col-12 col-md-6 col-lg-3">
-            <div class="card infra-card-warning">
+            <div class="card infra-card-warning h-100">
                 <div class="card-body">
                     <div class="d-flex justify-content-between align-items-start">
                         <div>
@@ -88,7 +94,7 @@
 
         <!-- Bed Temperature Card -->
         <div class="col-12 col-md-6 col-lg-3">
-            <div class="card infra-card-danger">
+            <div class="card infra-card-danger h-100">
                 <div class="card-body">
                     <div class="d-flex justify-content-between align-items-start">
                         <div>
@@ -103,7 +109,7 @@
 
         <!-- Print Progress Card -->
         <div class="col-12 col-md-6 col-lg-3">
-            <div class="card infra-card-info">
+            <div class="card infra-card-info h-100">
                 <div class="card-body">
                     <div class="d-flex justify-content-between align-items-start">
                         <div>
@@ -118,7 +124,7 @@
 
         <!-- Chamber Light Card -->
         <div class="col-12 col-md-6 col-lg-3">
-            <div class="card {% if stats.chamber_light == 'on' %}infra-card-success{% else %}infra-card-secondary{% endif %}">
+            <div class="card h-100 {% if stats.chamber_light == 'on' %}infra-card-success{% else %}infra-card-secondary{% endif %}">
                 <div class="card-body">
                     <div class="d-flex justify-content-between align-items-start">
                         <div>
@@ -158,37 +164,6 @@
     </div>
     {% endif %}
 
-    <!-- AMS Status Section -->
-    <div class="row mb-4">
-        <div class="col-12">
-            <div class="card">
-                <div class="card-header">
-                    <h5>AMS Status</h5>
-                </div>
-                <div class="card-body">
-                    <div class="row">
-                        <div class="col-md-4">
-                            <strong>Temperature:</strong>
-                            {% if stats.ams_temp %}
-                                {{ stats.ams_temp|floatformat:1 }}&deg;C
-                            {% else %}
-                                N/A
-                            {% endif %}
-                        </div>
-                        <div class="col-md-4">
-                            <strong>Humidity:</strong>
-                            {% if stats.ams_humidity %}
-                                {{ stats.ams_humidity }}%
-                            {% else %}
-                                N/A
-                            {% endif %}
-                        </div>
-                    </div>
-                </div>
-            </div>
-        </div>
-    </div>
-
     <!-- Filaments Section -->
     <div class="row mb-4">
         <div class="col-12">
@@ -198,34 +173,59 @@
                 </div>
                 <div class="card-body">
                     {% if stats.filaments %}
-                    <div class="row g-3">
+                    {% if stats.ams_units|length > 1 %}
-                        {% for filament in stats.filaments %}
+                    <div class="ams-filter-pills mb-3" id="amsFilterPills">
-                        <div class="col-12 col-md-6 col-lg-3">
+                        <button type="button" class="btn ams-filter-pill active" data-ams-filter="all">All</button>
-                            <div class="card filament-card" data-filament-color="{{ filament.color|slice:':6' }}"{% if filament.is_transparent %} data-filament-transparent="true"{% endif %}>
+                        {% for unit in stats.ams_units %}
-                                <div class="card-body">
+                        <button type="button" class="btn ams-filter-pill ams-badge-{{ unit.ams_type|slugify }}" data-ams-filter="{{ unit.ams_unit_id }}">{{ unit.ams_type|default:"AMS" }}</button>
-                                    <div class="d-flex justify-content-between align-items-center mb-2">
+                        {% endfor %}
-                                        <h6 class="mb-0">Tray {{ filament.tray_id }}</h6>
+                    </div>
-                                        {% if filament.filament_pk %}
+                    {% endif %}
-                                        <a href="{% url 'bambu_run:filament_detail' filament.filament_pk %}" class="text-decoration-none" title="View in inventory">
+                    <div class="row g-3 ams-groups">
-                                            <svg class="icon icon-sm text-body-secondary"><use href="{% static 'bambu_run/vendors/coreui-icons-free.svg' %}#cil-external-link"></use></svg>
+                        {% for group in stats.ams_groups %}
-                                        </a>
+                        <div class="{% if group.filaments|length > 1 %}col-12{% else %}col-12 col-md-6 col-lg-3{% endif %} ams-group ams-badge-bg-{{ group.ams_type|slugify }}" data-ams-unit-id="{{ group.unit_id }}">
-                                        {% endif %}
+                            <div class="ams-group-header d-flex justify-content-between align-items-center mb-2">
-                                    </div>
+                                <strong class="small">{{ group.label }}</strong>
-                                    <p class="mb-1 small"><strong>{{ filament.type }}</strong> - {{ filament.brand }}</p>
+                                {% if group.humidity is not None or group.temp is not None %}
-                                    {% if filament.color_name %}<p class="mb-1 small text-body-secondary">{{ filament.color_name }}</p>{% endif %}
+                                <span class="small text-body-secondary">
-                                    <div class="d-flex justify-content-between align-items-center mb-2">
+                                    {% if group.humidity is not None %}{{ group.humidity }}%RH{% endif %}
-                                        <span class="small">Remaining</span>
+                                    {% if group.temp is not None %}&middot; {{ group.temp }}&deg;C{% endif %}
-                                        <span class="badge filament-badge">{{ filament.remain_percent }}%</span>
+                                </span>
-                                    </div>
+                                {% endif %}
-                                    <div class="progress" style="height: 10px; background-color: rgba(0,0,0,0.1);">
+                            </div>
-                                        <div class="progress-bar filament-progress" role="progressbar" style="width: {{ filament.remain_percent }}%;" aria-valuenow="{{ filament.remain_percent }}" aria-valuemin="0" aria-valuemax="100"></div>
+                            <div class="row g-3">
+                                {% for filament in group.filaments %}
+                                <div class="col-12 {% if group.filaments|length > 1 %}col-md-6 col-lg-3{% endif %}">
+                                    <div class="card filament-card" data-filament-color="{{ filament.color|slice:':6' }}"{% if filament.is_transparent %} data-filament-transparent="true"{% endif %}>
+                                        <div class="card-body">
+                                            <div class="d-flex justify-content-between align-items-center mb-2">
+                                                <h6 class="mb-0">Tray {{ filament.tray_id }}</h6>
+                                                {% if filament.filament_pk %}
+                                                <a href="{% url 'bambu_run:filament_detail' filament.filament_pk %}" class="text-decoration-none" title="View in inventory">
+                                                    <svg class="icon icon-sm text-body-secondary"><use href="{% static 'bambu_run/vendors/coreui-icons-free.svg' %}#cil-external-link"></use></svg>
+                                                </a>
+                                                {% endif %}
+                                            </div>
+                                            <p class="mb-1 small"><strong>{{ filament.type }}</strong> - {{ filament.brand }}</p>
+                                            {% if filament.color_name %}<p class="mb-1 small text-body-secondary">{{ filament.color_name }}</p>{% endif %}
+                                            <div class="d-flex justify-content-between align-items-center mb-2">
+                                                <span class="small">Remaining</span>
+                                                <span class="badge filament-badge">{{ filament.remain_percent }}%</span>
+                                            </div>
+                                            <div class="progress" style="height: 10px; background-color: rgba(0,0,0,0.1);">
+                                                <div class="progress-bar filament-progress" role="progressbar" style="width: {{ filament.remain_percent }}%;" aria-valuenow="{{ filament.remain_percent }}" aria-valuemin="0" aria-valuemax="100"></div>
+                                            </div>
+                                        </div>
                                     </div>
                                 </div>
+                                {% endfor %}
                             </div>
                         </div>
                         {% endfor %}
+                    </div>
 
-                        {% if stats.external_spool.type %}
+                    {% if stats.external_spool.type %}
+                    <div class="row g-3 mt-1">
                         <div class="col-12 col-md-6 col-lg-3">
                             <div class="card filament-card" data-filament-color="{{ stats.external_spool.color|slice:':6' }}">
                                 <div class="card-body">
@@ -241,8 +241,8 @@
                                 </div>
                             </div>
                         </div>
-                        {% endif %}
                     </div>
+                    {% endif %}
                     {% else %}
                     <p class="text-body-secondary">No filament data available</p>
                     {% endif %}
@@ -251,6 +251,64 @@
         </div>
     </div>
 
+    <!-- Hotends Section (Vortek rack + any plain/non-inductive nozzles) -->
+    {% if stats.hotends or stats.nozzle_positions %}
+    <div class="row mb-4">
+        <div class="col-12">
+            <div class="card">
+                <div class="card-header">
+                    <h5>Hotends</h5>
+                </div>
+                <div class="card-body">
+                    <div class="row g-3">
+                        {% for hotend in stats.hotends %}
+                        <div class="col-12 col-md-6 col-lg-3">
+                            <div class="card filament-card" data-filament-color="{{ hotend.last_color|default:'888888' }}">
+                                <div class="card-body">
+                                    <div class="d-flex justify-content-between align-items-center mb-2">
+                                        <h6 class="mb-0">
+                                            {% if hotend.is_toolhead %}Toolhead{% elif hotend.slot_number %}Slot {{ hotend.slot_number }}{% else %}Rack{% endif %}
+                                        </h6>
+                                        {% if hotend.is_toolhead %}<span class="badge filament-badge">Toolhead</span>{% endif %}
+                                    </div>
+                                    <p class="mb-1 small text-body-secondary">SN {{ hotend.serial_number }}</p>
+                                    <p class="mb-1 small"><strong>{{ hotend.nozzle_type }}</strong>{% if hotend.diameter %} &middot; {{ hotend.diameter }}mm{% endif %}</p>
+                                    {% if hotend.last_filament_profile_id %}<p class="mb-1 small text-body-secondary">Last: {{ hotend.last_filament_profile_id }}</p>{% endif %}
+                                    <div class="d-flex justify-content-between align-items-center mb-1">
+                                        <span class="small">Used time</span>
+                                        <span class="small">{{ hotend.used_time_display }}</span>
+                                    </div>
+                                    <div class="d-flex justify-content-between align-items-center mb-2">
+                                        <span class="small">Wear</span>
+                                        <span class="badge filament-badge">{{ hotend.wear_percent|floatformat:0 }}%</span>
+                                    </div>
+                                    <div class="progress" style="height: 10px; background-color: rgba(0,0,0,0.1);">
+                                        <div class="progress-bar filament-progress" role="progressbar" style="width: {{ hotend.wear_percent }}%;" aria-valuenow="{{ hotend.wear_percent }}" aria-valuemin="0" aria-valuemax="100"></div>
+                                    </div>
+                                </div>
+                            </div>
+                        </div>
+                        {% endfor %}
+                        {% for nozzle in stats.nozzle_positions %}
+                        <div class="col-12 col-md-6 col-lg-3">
+                            <div class="card">
+                                <div class="card-body">
+                                    <div class="d-flex justify-content-between align-items-center mb-2">
+                                        <h6 class="mb-0">{% if nozzle.is_toolhead %}Toolhead{% else %}Fixed Nozzle{% endif %}</h6>
+                                    </div>
+                                    <p class="mb-1 small"><strong>{{ nozzle.nozzle_type }}</strong>{% if nozzle.diameter %} &middot; {{ nozzle.diameter }}mm{% endif %}</p>
+                                    <p class="mb-0 small text-body-secondary">No induction chip data</p>
+                                </div>
+                            </div>
+                        </div>
+                        {% endfor %}
+                    </div>
+                </div>
+            </div>
+        </div>
+    </div>
+    {% endif %}
+
     <!-- Date/Time Filter Controls -->
     {% if not is_basic_user %}
     <div class="row mb-4">
@@ -467,4 +525,27 @@
     });
 </script>
 {% endif %}
+<script>
+    document.addEventListener('DOMContentLoaded', function() {
+        const pillsContainer = document.getElementById('amsFilterPills');
+        if (!pillsContainer) return;
+        const items = document.querySelectorAll('.ams-groups .ams-group');
+
+        pillsContainer.addEventListener('click', function(e) {
+            const pill = e.target.closest('.ams-filter-pill');
+            if (!pill) return;
+
+            pillsContainer.querySelectorAll('.ams-filter-pill').forEach(function(p) {
+                p.classList.remove('active');
+            });
+            pill.classList.add('active');
+
+            const filter = pill.dataset.amsFilter;
+            items.forEach(function(item) {
+                const show = filter === 'all' || item.dataset.amsUnitId === filter;
+                item.classList.toggle('d-none', !show);
+            });
+        });
+    });
+</script>
 {% endblock %}

bambu_run/views.py

@@ -11,12 +11,16 @@ import json
 import zoneinfo
 
 from .conf import app_settings
-from .models import Printer, PrinterMetrics, Filament, FilamentColor, FilamentType, FilamentSnapshot, PrintJob, FilamentUsage
+from .models import Printer, PrinterMetrics, Filament, FilamentColor, FilamentType, FilamentSnapshot, PrintJob, FilamentUsage, Hotend
 from .forms import FilamentForm, FilamentColorForm, FilamentTypeForm
 
+# Every field the chart serializers read must be listed here. A field that is
+# accessed but missing triggers a deferred-field load — one extra SELECT per row,
+# which turns a single-query page into thousands.
 _METRICS_API_FIELDS = [
     'id', 'device_id', 'timestamp',
     'nozzle_temp', 'nozzle_target_temp',
+    'nozzle_temp_left', 'nozzle_target_temp_left',
     'bed_temp', 'bed_target_temp',
     'print_percent', 'cooling_fan_speed', 'heatbreak_fan_speed',
     'wifi_signal_dbm', 'ams_humidity_raw', 'ams_temp',
@@ -25,6 +29,9 @@ _METRICS_API_FIELDS = [
     'external_spool',
 ]
 _MAX_CHART_POINTS = 3000
+# Fallback window for requests that don't specify a full date range. Without it a
+# bare API call scans the entire metrics table.
+_DEFAULT_WINDOW = timedelta(hours=24)
 
 
 def resolve_printer_from_request(pk):
@@ -32,12 +39,47 @@ def resolve_printer_from_request(pk):
 
     `pk` given (URL kwarg) -> that exact printer, 404 if missing/inactive.
     `pk` omitted -> first active printer (today's single-printer default behavior).
+
+    Both paths go through `Printer.objects`, which is category-scoped, so a
+    non-printer row sharing `infrastructure_device` (a NAS, a router) can never be
+    resolved as "the printer" — even when no active printer exists.
     """
     if pk is not None:
         return get_object_or_404(Printer, pk=pk, is_active=True)
     return Printer.objects.filter(is_active=True).first()
 
 
+def sample_metrics(metrics_list, max_points=None):
+    """Evenly thin a metrics list to at most `max_points`, always keeping the last
+    reading — the stat cards are built from it."""
+    max_points = max_points or _MAX_CHART_POINTS
+    total = len(metrics_list)
+    if total <= max_points:
+        return metrics_list
+    step = (total // max_points) + 1
+    sampled = metrics_list[::step]
+    if sampled[-1] is not metrics_list[-1]:
+        sampled.append(metrics_list[-1])
+    return sampled
+
+
+def fetch_snapshots_by_metric(metrics_list):
+    """Load filament snapshots for exactly the metrics we're serializing.
+
+    Beats `prefetch_related` on the unsampled queryset, which pulls a snapshot row
+    for every metric in the window (~25k rows for 24h) including the ones sampling
+    just discarded.
+    """
+    if not metrics_list:
+        return {}
+    snapshots_by_metric = {}
+    for snap in FilamentSnapshot.objects.filter(
+        printer_metric_id__in=[m.id for m in metrics_list]
+    ):
+        snapshots_by_metric.setdefault(snap.printer_metric_id, []).append(snap)
+    return snapshots_by_metric
+
+
 class PrinterDashboardView(LoginRequiredMixin, TemplateView):
     template_name = "bambu_run/printer_dashboard.html"
 
@@ -72,14 +114,28 @@ class PrinterDashboardView(LoginRequiredMixin, TemplateView):
 
         # Get date range (overridable by subclasses)
         start_dt, end_dt = self._get_date_range(self.request)
-        metrics = PrinterMetrics.objects.filter(
+        query = PrinterMetrics.objects.filter(
             device=printer_device, timestamp__gte=start_dt
         )
         if end_dt:
-            metrics = metrics.filter(timestamp__lte=end_dt)
+            query = query.filter(timestamp__lte=end_dt)
-        metrics = metrics.prefetch_related('filament_snapshots').order_by("timestamp")
 
-        latest_metric = metrics.last()
+        # Chart series only need the columns the serializer below reads, and only
+        # as many points as a chart can render. Fetching every column (including
+        # the large JSON blobs) for every row is what made this page slow.
+        metrics = sample_metrics(
+            list(query.only(*_METRICS_API_FIELDS).order_by("timestamp"))
+        )
+        snapshots_by_metric = fetch_snapshots_by_metric(metrics)
+
+        # The stat cards read far more fields than the charts do, so the latest
+        # reading is fetched separately as a full instance rather than deferring
+        # (a deferred field on a sampled row costs an extra query per access).
+        latest_metric = (
+            query.prefetch_related('filament_snapshots__filament')
+            .order_by("-timestamp")
+            .first()
+        )
 
         printer_data_json = {
             "timestamps": [
@@ -133,14 +189,17 @@ class PrinterDashboardView(LoginRequiredMixin, TemplateView):
             "total_layer_num": [
                 m.total_layer_num if m.total_layer_num else 0 for m in metrics
             ],
-            "filament_timeline": self._prepare_filament_timeline(metrics),
+            "filament_timeline": self._prepare_filament_timeline(
+                metrics, snapshots_by_metric
+            ),
         }
 
         stats = {}
         if latest_metric:
             filaments_list = []
             try:
-                filament_snapshots = latest_metric.filament_snapshots.select_related('filament').all()
+                # `.all()` (not `.select_related()`) so the prefetch cache is used
+                filament_snapshots = latest_metric.filament_snapshots.all()
                 for snapshot in filament_snapshots:
                     filament_dict = {
                         'tray_id': snapshot.tray_id,
@@ -148,6 +207,8 @@ class PrinterDashboardView(LoginRequiredMixin, TemplateView):
                         'brand': snapshot.sub_type or 'Unknown',
                         'color': snapshot.color or 'FFFFFFFF',
                         'remain_percent': snapshot.remain_percent or 0,
+                        'ams_unit_id': snapshot.ams_unit_id,
+                        'ams_type': snapshot.ams_type or '',
                     }
                     if snapshot.filament:
                         filament_dict['color_name'] = snapshot.filament.color
@@ -157,6 +218,52 @@ class PrinterDashboardView(LoginRequiredMixin, TemplateView):
             except Exception:
                 filaments_list = []
 
+            # Build a lookup from unit_id → AMS unit metadata (humidity, temp, info code)
+            # first so we can enrich blank ams_type values derived from old snapshots.
+            units_meta = {
+                u.get('unit_id'): u for u in (latest_metric.ams_units or [])
+            }
+
+            # Distinct AMS units in this snapshot. ams_type stored on FilamentSnapshot
+            # may be blank for rows written before the multi-AMS deploy — fall back to
+            # re-deriving from the unit's info code so labels always show correctly.
+            from .models import ams_type_from_info as _ams_type_from_info
+            seen_units = {}
+            for f in filaments_list:
+                uid = f.get('ams_unit_id')
+                if uid is not None and uid not in seen_units:
+                    label = f.get('ams_type') or ''
+                    if not label:
+                        unit_meta = units_meta.get(str(uid), {})
+                        label = _ams_type_from_info(unit_meta.get('info', ''))
+                    seen_units[uid] = label
+            ams_units_list = [
+                {'ams_unit_id': uid, 'ams_type': label}
+                for uid, label in sorted(seen_units.items())
+            ]
+
+            ams_groups = []
+            ungrouped = [f for f in filaments_list if f.get('ams_unit_id') is None]
+            if ungrouped:
+                ams_groups.append({
+                    'unit_id': None,
+                    'ams_type': '',
+                    'label': 'AMS',
+                    'humidity': None,
+                    'temp': None,
+                    'filaments': ungrouped,
+                })
+            for uid, label in sorted(seen_units.items()):
+                unit_meta = units_meta.get(str(uid), {})
+                ams_groups.append({
+                    'unit_id': uid,
+                    'ams_type': label,
+                    'label': f"{label or 'AMS'} (Unit {uid})",
+                    'humidity': unit_meta.get('humidity'),
+                    'temp': unit_meta.get('temp'),
+                    'filaments': [f for f in filaments_list if f.get('ams_unit_id') == uid],
+                })
+
             subtask_name = latest_metric.subtask_name or "No active print"
             # Look up active PrintJob for a better display name (cloud design_title)
             job_display_name = subtask_name
@@ -196,22 +303,37 @@ class PrinterDashboardView(LoginRequiredMixin, TemplateView):
                 "ams_temp": float(latest_metric.ams_temp) if latest_metric.ams_temp else None,
                 "ams_humidity": latest_metric.ams_humidity,
                 "filaments": filaments_list,
+                "ams_units": ams_units_list,
+                "ams_groups": ams_groups,
+                "hotends": list(
+                    Hotend.objects.filter(printer=printer_device)
+                    .order_by('-is_toolhead', 'slot_number', 'serial_number')
+                ),
+                # Nozzle positions with no induction chip (no stable serial number to
+                # key a Hotend registry row on, e.g. H2C's fixed left nozzle) — shown
+                # read-only from the latest poll, not persisted/historical. Entries with
+                # no readable type/diameter at all (i.e. genuinely nothing there) are
+                # dropped rather than shown as an empty placeholder.
+                "nozzle_positions": [
+                    h for h in (latest_metric.nozzle_info or [])
+                    if h.get('is_empty') and (h.get('nozzle_type') or h.get('diameter'))
+                ],
                 "external_spool": latest_metric.external_spool or {},
                 "timestamp": latest_metric.timestamp.astimezone(tz).strftime("%Y-%m-%d %H:%M:%S"),
             }
 
-        project_markers = self._calculate_project_markers(list(metrics), tz)
+        project_markers = self._calculate_project_markers(metrics, tz, printer_device)
         printer_data_json["project_markers"] = project_markers
 
         context["printer_device"] = printer_device
         context["device_name"] = printer_device.name
         context["stats"] = stats
-        context["metrics_count"] = metrics.count()
+        context["metrics_count"] = len(metrics)
         context["printer_data_json"] = json.dumps(printer_data_json)
 
         return context
 
-    def _calculate_project_markers(self, metrics, timezone_info):
+    def _calculate_project_markers(self, metrics, timezone_info, device):
         """Calculate where print jobs start and end, using cloud design_title when available."""
         if not metrics:
             return []
@@ -219,7 +341,6 @@ class PrinterDashboardView(LoginRequiredMixin, TemplateView):
         # Build a lookup: subtask_name -> display_name from PrintJobs in this time window
         window_start = metrics[0].timestamp
         window_end = metrics[-1].timestamp
-        device = metrics[0].device
         jobs_qs = PrintJob.objects.filter(
             device=device,
             start_time__gte=window_start - timedelta(minutes=5),
@@ -265,28 +386,31 @@ class PrinterDashboardView(LoginRequiredMixin, TemplateView):
 
         return markers
 
-    def _prepare_filament_timeline(self, metrics):
+    def _prepare_filament_timeline(self, metrics, snapshots_by_metric):
-        """Prepare filament data organized by unique filament configurations."""
+        """Prepare filament data organized by unique filament configurations.
+
+        Snapshots are passed in pre-grouped by metric id; reading them off each
+        metric instance instead would issue one query per point.
+        """
         filament_data = {}
         total_points = len(metrics)
 
         for idx, metric in enumerate(metrics):
-            try:
+            for snapshot in snapshots_by_metric.get(metric.id, []):
-                snapshots = metric.filament_snapshots.all()
-            except Exception:
-                snapshots = []
-
-            for snapshot in snapshots:
                 tray_id = snapshot.tray_id
+                ams_unit_id = snapshot.ams_unit_id
+                ams_type = snapshot.ams_type or ''
                 fil_type = snapshot.type or 'Unknown'
                 fil_sub_type = snapshot.sub_type or 'Unknown'
                 fil_color = snapshot.color or 'FFFFFFFF'
 
-                unique_key = f"{tray_id}_{fil_type}_{fil_sub_type}_{fil_color}"
+                unique_key = f"{ams_unit_id}_{tray_id}_{fil_type}_{fil_sub_type}_{fil_color}"
 
                 if unique_key not in filament_data:
                     filament_data[unique_key] = {
                         'tray_id': tray_id,
+                        'ams_unit_id': ams_unit_id,
+                        'ams_type': ams_type,
                         'type': fil_type,
                         'brand': fil_sub_type,
                         'color': fil_color,
@@ -348,38 +472,25 @@ class PrinterDataAPIView(LoginRequiredMixin, View):
                 .only(*_METRICS_API_FIELDS)
             )
 
-            if start_date and start_time and end_date and end_time:
+            # Both bounds are always applied. A missing bound falls back to a 24h
-                start_dt = datetime.strptime(f"{start_date} {start_time}", "%Y-%m-%d %H:%M").replace(tzinfo=tz)
+            # window rather than being left open — an unbounded range would scan
-                end_dt = datetime.strptime(f"{end_date} {end_time}", "%Y-%m-%d %H:%M").replace(tzinfo=tz)
+            # every metric ever recorded.
-                query = query.filter(timestamp__gte=start_dt, timestamp__lte=end_dt)
+            def _parse(date_str, time_str):
-                range_seconds = (end_dt - start_dt).total_seconds()
+                return datetime.strptime(
-                expected_count = max(1, int(range_seconds / 30))
+                    f"{date_str} {time_str}", "%Y-%m-%d %H:%M"
-            elif start_date and start_time:
+                ).replace(tzinfo=tz)
-                start_dt = datetime.strptime(f"{start_date} {start_time}", "%Y-%m-%d %H:%M").replace(tzinfo=tz)
-                query = query.filter(timestamp__gte=start_dt)
-                expected_count = _MAX_CHART_POINTS
-            elif end_date and end_time:
-                end_dt = datetime.strptime(f"{end_date} {end_time}", "%Y-%m-%d %H:%M").replace(tzinfo=tz)
-                query = query.filter(timestamp__lte=end_dt)
-                expected_count = _MAX_CHART_POINTS
-            else:
-                expected_count = _MAX_CHART_POINTS
 
-            step = max(1, expected_count // _MAX_CHART_POINTS)
+            end_dt = _parse(end_date, end_time) if end_date else timezone.now()
+            start_dt = _parse(start_date, start_time) if start_date else end_dt - _DEFAULT_WINDOW
+            query = query.filter(timestamp__gte=start_dt, timestamp__lte=end_dt)
 
             # Stage B: single DB round-trip, downsample in Python
-            metrics_list = list(query.order_by("timestamp"))
+            metrics_list = sample_metrics(list(query.order_by("timestamp")))
-            if step > 1:
-                metrics_list = metrics_list[::step]
 
             total_points = len(metrics_list)
 
             # Stage C: targeted snapshot fetch (only sampled IDs)
-            snapshots_by_metric: dict = {}
+            snapshots_by_metric = fetch_snapshots_by_metric(metrics_list)
-            if metrics_list:
-                sampled_ids = [m.id for m in metrics_list]
-                for snap in FilamentSnapshot.objects.filter(printer_metric_id__in=sampled_ids):
-                    snapshots_by_metric.setdefault(snap.printer_metric_id, []).append(snap)
 
             # Stage D: single-pass serialization
             timestamps = []

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "bambu-run"
-version = "0.1.7"
+version = "0.1.10"
 description = "Django reusable app for Bambu Lab 3D printer monitoring and filament inventory management"
 readme = "README.md"
 license = {text = "MIT"}

tests/test_ams_type_from_info.py

@@ -0,0 +1,25 @@
+import pytest
+
+from bambu_run.models import ams_type_from_info
+
+
+@pytest.mark.parametrize(
+    "info_code,expected",
+    [
+        # Real-world 8-char info codes captured from a live H2C with
+        # AMS 2 Pro (unit 0), AMS (unit 1), AMS HT (unit 128).
+        ("10001003", "AMS 2 Pro"),
+        ("10001001", "AMS"),
+        ("11002104", "AMS HT"),
+        # Bare 4-digit codes (original assumption) still resolve.
+        ("1001", "AMS"),
+        ("1003", "AMS 2 Pro"),
+        ("2104", "AMS HT"),
+        # Unknown/missing codes resolve to empty string, not an error.
+        ("99999999", ""),
+        ("", ""),
+        (None, ""),
+    ],
+)
+def test_ams_type_from_info(info_code, expected):
+    assert ams_type_from_info(info_code) == expected

tests/test_filament_context.py

@@ -0,0 +1,185 @@
+import pytest
+from decimal import Decimal
+from django.urls import reverse
+from django.utils import timezone
+
+from bambu_run.models import Printer, PrinterMetrics, FilamentSnapshot
+
+
+@pytest.fixture
+def logged_in_client(client, django_user_model):
+    user = django_user_model.objects.create_user(username="tester", password="pw")
+    client.force_login(user)
+    return client
+
+
+@pytest.mark.django_db
+def test_dashboard_filaments_carry_ams_unit_info(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    metric = PrinterMetrics.objects.create(device=printer, timestamp=timezone.now())
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=0, ams_type="AMS",
+        type="PLA", remain_percent=80,
+    )
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=128, ams_type="AMS HT",
+        type="PA-CF", remain_percent=50,
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    filaments = resp.context["stats"]["filaments"]
+    assert len(filaments) == 2
+    units = {(f["ams_unit_id"], f["ams_type"]) for f in filaments}
+    assert units == {(0, "AMS"), (128, "AMS HT")}
+
+    ams_units = resp.context["stats"]["ams_units"]
+    assert ams_units == [
+        {"ams_unit_id": 0, "ams_type": "AMS"},
+        {"ams_unit_id": 128, "ams_type": "AMS HT"},
+    ]
+
+
+@pytest.mark.django_db
+def test_filament_timeline_keeps_same_tray_id_units_separate(logged_in_client):
+    from bambu_run.views import PrinterDashboardView
+
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    metric = PrinterMetrics.objects.create(device=printer, timestamp=timezone.now())
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=0, ams_type="AMS",
+        type="PLA", sub_type="PLA Basic", color="FF0000", remain_percent=80,
+    )
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=128, ams_type="AMS HT",
+        type="PLA", sub_type="PLA Basic", color="FF0000", remain_percent=50,
+    )
+
+    from bambu_run.views import fetch_snapshots_by_metric
+
+    view = PrinterDashboardView()
+    metrics = list(PrinterMetrics.objects.filter(pk=metric.pk))
+    timeline = view._prepare_filament_timeline(
+        metrics, fetch_snapshots_by_metric(metrics)
+    )
+
+    assert len(timeline) == 2
+
+
+@pytest.mark.django_db
+def test_dashboard_renders_unit_pills_and_badges_with_multiple_units(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    metric = PrinterMetrics.objects.create(device=printer, timestamp=timezone.now())
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=0, ams_type="AMS",
+        type="PLA", color="FF0000FF", remain_percent=80,
+    )
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=128, ams_type="AMS HT",
+        type="PA-CF", color="00FF00FF", remain_percent=50,
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    assert resp.status_code == 200
+    html = resp.content.decode()
+    assert "ams-filter-pills" in html
+    assert "ams-badge-ams" in html
+    assert "ams-badge-ams-ht" in html
+    assert 'data-ams-unit-id="0"' in html
+    assert 'data-ams-unit-id="128"' in html
+
+
+@pytest.mark.django_db
+def test_dashboard_groups_filaments_by_ams_unit(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    metric = PrinterMetrics.objects.create(
+        device=printer, timestamp=timezone.now(),
+        ams_units=[
+            {"unit_id": "0", "ams_type": "AMS 2 Pro", "humidity": 5, "temp": 22.5},
+            {"unit_id": "128", "ams_type": "AMS HT", "humidity": 8, "temp": 60.0},
+        ],
+    )
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=0, ams_type="AMS 2 Pro",
+        type="ABS", remain_percent=80,
+    )
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=1, ams_unit_id=0, ams_type="AMS 2 Pro",
+        type="ABS", remain_percent=60,
+    )
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=128, ams_type="AMS HT",
+        type="PA-CF", remain_percent=50,
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    groups = resp.context["stats"]["ams_groups"]
+    assert len(groups) == 2
+
+    ams2pro_group, ht_group = groups
+    assert ams2pro_group["unit_id"] == 0
+    assert ams2pro_group["label"] == "AMS 2 Pro (Unit 0)"
+    assert ams2pro_group["humidity"] == 5
+    assert ams2pro_group["temp"] == 22.5
+    assert len(ams2pro_group["filaments"]) == 2
+
+    assert ht_group["unit_id"] == 128
+    assert ht_group["label"] == "AMS HT (Unit 128)"
+    assert ht_group["humidity"] == 8
+    assert len(ht_group["filaments"]) == 1
+
+
+@pytest.mark.django_db
+def test_dashboard_renders_wide_and_compact_panels(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    metric = PrinterMetrics.objects.create(
+        device=printer, timestamp=timezone.now(),
+        ams_units=[
+            {"unit_id": "0", "ams_type": "AMS 2 Pro", "humidity": 5, "temp": 22.5},
+            {"unit_id": "128", "ams_type": "AMS HT", "humidity": 8, "temp": 60.0},
+        ],
+    )
+    for tray_id in range(4):
+        FilamentSnapshot.objects.create(
+            printer_metric=metric, tray_id=tray_id, ams_unit_id=0, ams_type="AMS 2 Pro",
+            type="ABS", remain_percent=80,
+        )
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=128, ams_type="AMS HT",
+        type="PA-CF", remain_percent=50,
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    html = resp.content.decode()
+    assert "col-12 ams-group" in html        # wide group: col-12 only
+    assert "col-lg-3 ams-group" in html      # compact group: col-lg-3
+    assert "AMS 2 Pro (Unit 0)" in html
+    assert "AMS HT (Unit 128)" in html
+
+
+@pytest.mark.django_db
+def test_dashboard_hides_unit_pills_with_single_unit(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    metric = PrinterMetrics.objects.create(device=printer, timestamp=timezone.now())
+    FilamentSnapshot.objects.create(
+        printer_metric=metric, tray_id=0, ams_unit_id=0, ams_type="AMS",
+        type="PLA", color="FF0000FF", remain_percent=80,
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    assert resp.status_code == 200
+    assert "ams-filter-pills" not in resp.content.decode()

tests/test_hotend_collection.py

@@ -0,0 +1,121 @@
+import pytest
+
+from bambu_run.management.commands.bambu_collector import Command, DeviceSession, resolve_printer_device
+from bambu_run.models import Hotend, HotendSnapshot, PrinterMetrics
+
+
+class FakeClient:
+    """Stub in place of BambuPrinter — returns canned snapshots, no real MQTT."""
+
+    def __init__(self, snapshots):
+        self._snapshots = snapshots
+        self._index = 0
+        self._client = None
+
+    def get_snapshot(self):
+        snap = self._snapshots[min(self._index, len(self._snapshots) - 1)]
+        self._index += 1
+        return snap
+
+
+def make_session(device_id, name, snapshots):
+    printer = resolve_printer_device(device_id, {"name": name, "dev_product_name": "H2C"})
+    return DeviceSession(device_id=device_id, client=FakeClient(snapshots), printer=printer)
+
+
+def hotends_snapshot(used_time=11472, wear=100.0):
+    return {
+        "gcode_state": "IDLE",
+        "hotends": [
+            {
+                "raw_id": 21, "serial_number": "20D06A5B2918952", "nozzle_type": "HS01",
+                "diameter": 0.4, "fila_id": "GFA01", "color": "FFFFFF",
+                "used_time_seconds": used_time, "wear_percent": wear, "stat": 0,
+                "is_toolhead": False, "is_empty": False, "slot_number": 6,
+            },
+            {
+                "raw_id": 1, "serial_number": "N/A", "nozzle_type": "HS01",
+                "diameter": 0.4, "fila_id": "", "color": None,
+                "used_time_seconds": 0, "wear_percent": 0.0, "stat": 0,
+                "is_toolhead": False, "is_empty": True, "slot_number": None,
+            },
+            {
+                "raw_id": 0, "serial_number": "20D06A5C0426280", "nozzle_type": "HS01",
+                "diameter": 0.4, "fila_id": "GFA00", "color": "FEC600",
+                "used_time_seconds": 93490, "wear_percent": 100.0, "stat": 0,
+                "is_toolhead": True, "is_empty": False, "slot_number": None,
+            },
+        ],
+    }
+
+
+@pytest.mark.django_db
+def test_first_poll_creates_one_hotend_per_non_empty_entry():
+    session = make_session("SERIAL-A", "Printer A", [hotends_snapshot()])
+
+    cmd = Command()
+    cmd.verbose = False
+    cmd._collect_printer_data(session)
+
+    hotends = Hotend.objects.filter(printer=session.printer)
+    assert hotends.count() == 2  # empty bay (sn="N/A") skipped
+
+    rack = hotends.get(serial_number="20D06A5B2918952")
+    assert rack.raw_id == 21
+    assert rack.slot_number == 6
+    assert rack.is_toolhead is False
+    assert rack.used_time_seconds == 11472
+    assert rack.wear_percent == 100.0
+    assert rack.nozzle_type == "HS01"
+    assert rack.last_filament_profile_id == "GFA01"
+    assert rack.last_color == "FFFFFF"
+
+    toolhead = hotends.get(serial_number="20D06A5C0426280")
+    assert toolhead.is_toolhead is True
+    assert toolhead.slot_number is None
+
+
+@pytest.mark.django_db
+def test_first_poll_creates_one_snapshot_per_non_empty_hotend():
+    session = make_session("SERIAL-A", "Printer A", [hotends_snapshot()])
+
+    cmd = Command()
+    cmd.verbose = False
+    cmd._collect_printer_data(session)
+
+    metric = PrinterMetrics.objects.get(device=session.printer)
+    assert HotendSnapshot.objects.filter(printer_metric=metric).count() == 2
+
+
+@pytest.mark.django_db
+def test_collector_persists_raw_nozzle_info_including_non_inductive_entries():
+    session = make_session("SERIAL-A", "Printer A", [hotends_snapshot()])
+
+    cmd = Command()
+    cmd.verbose = False
+    cmd._collect_printer_data(session)
+
+    metric = PrinterMetrics.objects.get(device=session.printer)
+    assert len(metric.nozzle_info) == 3  # all entries, including the empty/non-inductive one
+    serials = {h["serial_number"] for h in metric.nozzle_info}
+    assert serials == {"20D06A5B2918952", "N/A", "20D06A5C0426280"}
+
+
+@pytest.mark.django_db
+def test_second_poll_updates_existing_hotend_instead_of_duplicating():
+    session = make_session(
+        "SERIAL-A", "Printer A",
+        [hotends_snapshot(used_time=11472, wear=100.0), hotends_snapshot(used_time=11500, wear=100.0)],
+    )
+
+    cmd = Command()
+    cmd.verbose = False
+    cmd._collect_printer_data(session)
+    cmd._collect_printer_data(session)
+
+    hotends = Hotend.objects.filter(printer=session.printer, serial_number="20D06A5B2918952")
+    assert hotends.count() == 1
+    assert hotends.first().used_time_seconds == 11500
+
+    snapshots = HotendSnapshot.objects.filter(hotend=hotends.first())
+    assert snapshots.count() == 2

tests/test_hotend_dashboard.py

@@ -0,0 +1,128 @@
+import pytest
+from django.urls import reverse
+from django.utils import timezone
+
+from bambu_run.models import Printer, PrinterMetrics, Hotend
+
+
+@pytest.fixture
+def logged_in_client(client, django_user_model):
+    user = django_user_model.objects.create_user(username="tester", password="pw")
+    client.force_login(user)
+    return client
+
+
+@pytest.mark.django_db
+def test_dashboard_context_includes_hotends_toolhead_first(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    PrinterMetrics.objects.create(device=printer, timestamp=timezone.now())
+
+    Hotend.objects.create(
+        printer=printer, serial_number="RACK-SN", raw_id=16, slot_number=1,
+        is_toolhead=False, nozzle_type="HS01", used_time_seconds=3600, wear_percent=50,
+    )
+    Hotend.objects.create(
+        printer=printer, serial_number="TOOLHEAD-SN", raw_id=0, slot_number=None,
+        is_toolhead=True, nozzle_type="HS01", used_time_seconds=7200, wear_percent=80,
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    hotends = resp.context["stats"]["hotends"]
+    assert len(hotends) == 2
+    assert hotends[0].serial_number == "TOOLHEAD-SN"
+    assert hotends[1].serial_number == "RACK-SN"
+
+
+@pytest.mark.django_db
+def test_dashboard_context_includes_non_inductive_nozzle_positions(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    PrinterMetrics.objects.create(
+        device=printer, timestamp=timezone.now(),
+        nozzle_info=[
+            {
+                "raw_id": 1, "serial_number": "N/A", "nozzle_type": "HS01", "diameter": 0.4,
+                "fila_id": "", "color": None, "used_time_seconds": 0, "wear_percent": 0.0,
+                "stat": 0, "is_toolhead": False, "is_empty": True, "slot_number": None,
+            },
+        ],
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    positions = resp.context["stats"]["nozzle_positions"]
+    assert len(positions) == 1
+    assert positions[0]["nozzle_type"] == "HS01"
+
+
+@pytest.mark.django_db
+def test_dashboard_omits_nozzle_positions_with_no_readable_data(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    PrinterMetrics.objects.create(
+        device=printer, timestamp=timezone.now(),
+        nozzle_info=[
+            {
+                "raw_id": 1, "serial_number": "N/A", "nozzle_type": "", "diameter": 0,
+                "fila_id": "", "color": None, "used_time_seconds": 0, "wear_percent": 0.0,
+                "stat": 0, "is_toolhead": False, "is_empty": True, "slot_number": None,
+            },
+        ],
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    assert resp.context["stats"]["nozzle_positions"] == []
+    assert "<h5>Hotends</h5>" not in resp.content.decode()
+
+
+@pytest.mark.django_db
+def test_dashboard_renders_nozzle_position_without_serial_or_wear(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    PrinterMetrics.objects.create(
+        device=printer, timestamp=timezone.now(),
+        nozzle_info=[
+            {
+                "raw_id": 1, "serial_number": "N/A", "nozzle_type": "HS01", "diameter": 0.4,
+                "fila_id": "", "color": None, "used_time_seconds": 0, "wear_percent": 0.0,
+                "stat": 0, "is_toolhead": False, "is_empty": True, "slot_number": None,
+            },
+        ],
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    html = resp.content.decode()
+    assert "Hotends" in html
+    assert "HS01" in html
+    assert "SN: N/A" not in html
+    assert "SN N/A" not in html
+
+
+@pytest.mark.django_db
+def test_dashboard_renders_hotends_card(logged_in_client):
+    printer = Printer.objects.create(name="Printer A", model="H2C", is_active=True)
+    PrinterMetrics.objects.create(device=printer, timestamp=timezone.now())
+
+    Hotend.objects.create(
+        printer=printer, serial_number="RACK-SN", raw_id=18, slot_number=3,
+        is_toolhead=False, nozzle_type="HS01", diameter=0.4,
+        used_time_seconds=3661, wear_percent=50, last_filament_profile_id="GFA01",
+        last_color="DE4343",
+    )
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_dashboard", kwargs={"pk": printer.pk})
+    )
+
+    html = resp.content.decode()
+    assert "Hotends" in html
+    assert "RACK-SN" in html
+    assert "Slot 3" in html

tests/test_hotend_parsing.py

@@ -0,0 +1,100 @@
+from bambu_run.mqtt_client import PrinterState
+
+
+def real_nozzle_payload():
+    """Real captured device.nozzle payload from a live H2C with a Vortek rack
+    (1x AMS, 1x AMS 2 Pro, 1x AMS HT physically connected — unrelated here).
+    SN/used-time cross-checked against the user's Bambu Studio Hotends Info table."""
+    return {
+        "exist": 3997699,
+        "src_id": 17,
+        "tar_id": 17,
+        "state": 0,
+        "info": [
+            {"id": 21, "sn": "20D06A5B2918952", "type": "HS01", "diameter": 0.4,
+             "fila_id": "GFA01", "color_m": "FFFFFFFF", "p_t": 11472, "wear": 128.0, "stat": 0, "tm": 350},
+            {"id": 1, "sn": "N/A", "type": "HS01", "diameter": 0.4,
+             "fila_id": "", "color_m": "00000000", "p_t": 0, "wear": 0.0, "stat": 0, "tm": 0},
+            {"id": 16, "sn": "20D06A5B2919219", "type": "HS01", "diameter": 0.4,
+             "fila_id": "GFA01", "color_m": "A3D8E1FF", "p_t": 105386, "wear": 128.0, "stat": 0, "tm": 350},
+            {"id": 20, "sn": "20D06A590610257", "type": "HS01", "diameter": 0.4,
+             "fila_id": "GFG01", "color_m": "00000000", "p_t": 81506, "wear": 128.0, "stat": 0, "tm": 350},
+            {"id": 18, "sn": "20D06A591506263", "type": "HS01", "diameter": 0.4,
+             "fila_id": "GFA01", "color_m": "DE4343FF", "p_t": 30962, "wear": 128.0, "stat": 0, "tm": 350},
+            {"id": 0, "sn": "20D06A5C0426280", "type": "HS01", "diameter": 0.4,
+             "fila_id": "GFA00", "color_m": "FEC600FF", "p_t": 93490, "wear": 128.0, "stat": 0, "tm": 350},
+            {"id": 19, "sn": "20D06A5C0207881", "type": "HS01", "diameter": 0.4,
+             "fila_id": "GFA01", "color_m": "DE4343FF", "p_t": 1430, "wear": 128.0, "stat": 0, "tm": 350},
+        ],
+    }
+
+
+def make_data(nozzle_payload):
+    return {"print": {"gcode_state": "IDLE", "device": {"nozzle": nozzle_payload}}}
+
+
+def test_snapshot_includes_one_hotend_per_nozzle_info_entry():
+    state = PrinterState.from_mqtt_data(make_data(real_nozzle_payload()))
+    snapshot = state.get_snapshot()
+
+    assert len(snapshot["hotends"]) == 7
+
+
+def test_hotend_fields_extracted_correctly():
+    state = PrinterState.from_mqtt_data(make_data(real_nozzle_payload()))
+    snapshot = state.get_snapshot()
+
+    by_sn = {h["serial_number"]: h for h in snapshot["hotends"]}
+    h = by_sn["20D06A5B2919219"]
+
+    assert h["raw_id"] == 16
+    assert h["nozzle_type"] == "HS01"
+    assert h["diameter"] == 0.4
+    assert h["fila_id"] == "GFA01"
+    assert h["color"] == "A3D8E1"  # alpha stripped
+    assert h["used_time_seconds"] == 105386
+    assert h["wear_percent"] == 100.0  # 128/128*100
+    assert h["is_empty"] is False
+
+
+def test_id_zero_is_toolhead_and_resolves_slot_number():
+    state = PrinterState.from_mqtt_data(make_data(real_nozzle_payload()))
+    snapshot = state.get_snapshot()
+
+    by_sn = {h["serial_number"]: h for h in snapshot["hotends"]}
+    toolhead = by_sn["20D06A5C0426280"]
+
+    assert toolhead["raw_id"] == 0
+    assert toolhead["is_toolhead"] is True
+    assert toolhead["slot_number"] is None  # true bay address hidden while id==0 sentinel
+
+
+def test_rack_bay_ids_resolve_to_slot_numbers_one_through_six():
+    state = PrinterState.from_mqtt_data(make_data(real_nozzle_payload()))
+    snapshot = state.get_snapshot()
+
+    by_sn = {h["serial_number"]: h for h in snapshot["hotends"]}
+
+    assert by_sn["20D06A5B2919219"]["slot_number"] == 1  # raw_id 16
+    assert by_sn["20D06A591506263"]["slot_number"] == 3  # raw_id 18
+    assert by_sn["20D06A5C0207881"]["slot_number"] == 4  # raw_id 19
+    assert by_sn["20D06A590610257"]["slot_number"] == 5  # raw_id 20
+    assert by_sn["20D06A5B2918952"]["slot_number"] == 6  # raw_id 21
+
+
+def test_empty_bay_with_na_serial_is_flagged_empty():
+    state = PrinterState.from_mqtt_data(make_data(real_nozzle_payload()))
+    snapshot = state.get_snapshot()
+
+    by_sn = {h["serial_number"]: h for h in snapshot["hotends"]}
+    empty = by_sn["N/A"]
+
+    assert empty["is_empty"] is True
+    assert empty["is_toolhead"] is False
+
+
+def test_snapshot_hotends_empty_list_when_no_nozzle_payload():
+    state = PrinterState.from_mqtt_data({"print": {"gcode_state": "IDLE"}})
+    snapshot = state.get_snapshot()
+
+    assert snapshot["hotends"] == []

tests/test_multi_ams_collection.py

@@ -0,0 +1,104 @@
+import pytest
+
+from bambu_run.management.commands.bambu_collector import Command, DeviceSession, resolve_printer_device
+from bambu_run.models import Filament, FilamentSnapshot, FilamentUsage, PrinterMetrics
+
+
+class FakeClient:
+    """Stub in place of BambuPrinter — returns canned snapshots, no real MQTT."""
+
+    def __init__(self, snapshots):
+        self._snapshots = snapshots
+        self._index = 0
+        self._client = None
+
+    def get_snapshot(self):
+        snap = self._snapshots[min(self._index, len(self._snapshots) - 1)]
+        self._index += 1
+        return snap
+
+
+def make_session(device_id, name, snapshots):
+    printer = resolve_printer_device(device_id, {"name": name, "dev_product_name": "H2C"})
+    return DeviceSession(device_id=device_id, client=FakeClient(snapshots), printer=printer)
+
+
+def two_unit_tray0_snapshot():
+    """Two AMS units (AMS unit_id=0, AMS HT unit_id=128) both report tray_id=0,
+    with different filament types loaded — these must not collide."""
+    return {
+        "gcode_state": "IDLE",
+        "ams_units": [
+            {"unit_id": "0", "ams_type": "AMS", "humidity": 30, "temp": 25.0},
+            {"unit_id": "128", "ams_type": "AMS HT", "humidity": 20, "temp": 60.0},
+        ],
+        "filaments": [
+            {
+                "tray_id": 0, "type": "PLA", "sub_type": "PLA Basic", "color": "FF0000FF",
+                "tray_uuid": "UUID-UNIT0-TRAY0",
+                "remain_percent": 80, "ams_unit_id": 0, "ams_type": "AMS",
+            },
+            {
+                "tray_id": 0, "type": "PA-CF", "sub_type": "PA6-CF", "color": "00FF00FF",
+                "tray_uuid": "UUID-UNIT128-TRAY0",
+                "remain_percent": 50, "ams_unit_id": 128, "ams_type": "AMS HT",
+            },
+        ],
+    }
+
+
+@pytest.mark.django_db
+def test_two_ams_units_with_same_tray_id_create_distinct_snapshots():
+    session = make_session("SERIAL-A", "Printer A", [two_unit_tray0_snapshot()])
+
+    cmd = Command()
+    cmd.verbose = False
+    cmd._collect_printer_data(session)
+
+    metric = PrinterMetrics.objects.get(device=session.printer)
+    snapshots = FilamentSnapshot.objects.filter(printer_metric=metric).order_by("ams_unit_id")
+
+    assert snapshots.count() == 2
+
+    ams_snap, ht_snap = snapshots
+    assert ams_snap.tray_id == 0
+    assert ams_snap.ams_unit_id == 0
+    assert ams_snap.ams_type == "AMS"
+    assert ams_snap.type == "PLA"
+
+    assert ht_snap.tray_id == 0
+    assert ht_snap.ams_unit_id == 128
+    assert ht_snap.ams_type == "AMS HT"
+    assert ht_snap.type == "PA-CF"
+
+
+@pytest.mark.django_db
+def test_filament_usage_matches_correct_unit_when_tray_ids_collide():
+    start_snapshot = two_unit_tray0_snapshot()
+    start_snapshot.update({"gcode_state": "RUNNING", "subtask_name": "job_1", "print_percent": 1, "tray_now": "0"})
+
+    end_snapshot = two_unit_tray0_snapshot()
+    end_snapshot["filaments"][0]["remain_percent"] = 70  # AMS unit 0 consumed
+    end_snapshot["filaments"][1]["remain_percent"] = 50  # AMS HT unit 128 untouched
+    end_snapshot.update({"gcode_state": "FINISH", "subtask_name": "job_1", "print_percent": 100})
+
+    session = make_session("SERIAL-A", "Printer A", [start_snapshot, end_snapshot])
+
+    cmd = Command()
+    cmd.verbose = False
+    cmd._collect_printer_data(session)
+    cmd._collect_printer_data(session)
+
+    usages = FilamentUsage.objects.filter(print_job__device=session.printer).order_by("ams_unit_id")
+    # Both units reported tray_id=0 with a tracked filament loaded throughout the
+    # job — usage is recorded per physical unit, not collapsed into one ambiguous row.
+    assert usages.count() == 2
+
+    ams_usage, ht_usage = usages
+    assert ams_usage.ams_unit_id == 0
+    assert ams_usage.starting_percent == 80
+    assert ams_usage.ending_percent == 70
+
+    assert ht_usage.ams_unit_id == 128
+    assert ht_usage.starting_percent == 50
+    assert ht_usage.ending_percent == 50

tests/test_printer_device_scoping.py

@@ -0,0 +1,71 @@
+"""Printer shares the `infrastructure_device` table with non-printer devices
+(NAS, routers, ...) in host projects like RAE. Printer queries must never
+resolve one of those rows.
+"""
+
+import pytest
+from django.urls import reverse
+
+from bambu_run.models import Printer
+from bambu_run.views import resolve_printer_from_request
+
+
+@pytest.fixture
+def logged_in_client(client, django_user_model):
+    user = django_user_model.objects.create_user(username="scoping", password="pw")
+    client.force_login(user)
+    return client
+
+
+@pytest.fixture
+def nas():
+    """A non-printer device row sharing the table, sorting before any printer."""
+    return Printer.all_objects.create(
+        name="A NAS", model="DS920+", category="nas", is_active=True
+    )
+
+
+@pytest.mark.django_db
+def test_default_manager_excludes_non_printers(nas):
+    printer = Printer.objects.create(name="Z Printer", model="H2C", is_active=True)
+
+    assert list(Printer.objects.all()) == [printer]
+    assert nas in Printer.all_objects.all()
+
+
+@pytest.mark.django_db
+def test_new_printers_default_to_the_printer_category():
+    printer = Printer.objects.create(name="Fresh", model="H2C")
+
+    assert printer.category == Printer.CATEGORY_3D_PRINTER
+    assert printer in Printer.objects.all()
+
+
+@pytest.mark.django_db
+def test_resolve_printer_skips_an_active_nas(nas):
+    """The exact production failure: NAS sorts first and is active, printer is not."""
+    printer = Printer.objects.create(name="Z Printer", model="H2C", is_active=False)
+
+    assert resolve_printer_from_request(None) is None, "inactive printer must not resolve"
+
+    printer.is_active = True
+    printer.save()
+    assert resolve_printer_from_request(None) == printer
+
+
+@pytest.mark.django_db
+def test_resolve_printer_by_pk_rejects_a_non_printer(nas):
+    from django.http import Http404
+
+    with pytest.raises(Http404):
+        resolve_printer_from_request(nas.pk)
+
+
+@pytest.mark.django_db
+def test_dashboard_does_not_fall_back_to_a_nas(logged_in_client, nas):
+    resp = logged_in_client.get(reverse("bambu_run:printer_dashboard"))
+
+    assert resp.status_code == 200
+    assert "error" in resp.context
+    assert resp.context.get("printer_device") is None
+    assert list(resp.context["all_printers"]) == []

tests/test_printer_query_performance.py

@@ -0,0 +1,233 @@
+"""Guards against the query-count and payload regressions that made the printer
+pages slow: deferred-field N+1s, unbounded date ranges, and unsampled chart data.
+"""
+
+import json
+from datetime import timedelta
+
+import pytest
+from django.urls import reverse
+from django.utils import timezone
+
+from bambu_run.models import Printer, PrinterMetrics, FilamentSnapshot
+from bambu_run.views import _MAX_CHART_POINTS
+
+
+@pytest.fixture
+def logged_in_client(client, django_user_model):
+    user = django_user_model.objects.create_user(username="perf", password="pw")
+    client.force_login(user)
+    return client
+
+
+@pytest.fixture
+def printer():
+    return Printer.objects.create(name="Perf Printer", model="H2C", is_active=True)
+
+
+def _make_metrics(printer, count, *, snapshots_per_metric=2, spacing_seconds=30):
+    """Create `count` metrics ending now, each with some filament snapshots."""
+    now = timezone.now()
+    metrics = PrinterMetrics.objects.bulk_create(
+        [
+            PrinterMetrics(
+                device=printer,
+                timestamp=now - timedelta(seconds=spacing_seconds * (count - i)),
+                nozzle_temp=200 + i % 5,
+                nozzle_target_temp=220,
+                nozzle_temp_left=180 + i % 3,
+                nozzle_target_temp_left=190,
+                bed_temp=60,
+                bed_target_temp=60,
+                print_percent=i % 100,
+                gcode_state="RUNNING",
+                print_type="local",
+                subtask_name="job",
+            )
+            for i in range(count)
+        ]
+    )
+    FilamentSnapshot.objects.bulk_create(
+        [
+            FilamentSnapshot(
+                printer_metric=m,
+                tray_id=str(tray),
+                type="PLA",
+                sub_type="Bambu",
+                color="FF0000FF",
+                remain_percent=80,
+            )
+            for m in metrics
+            for tray in range(snapshots_per_metric)
+        ]
+    )
+    return metrics
+
+
+# --- Root cause 1: deferred-field N+1 in the API -----------------------------
+
+
+def _count_queries(client, url, params=None):
+    from django.db import connection
+    from django.test.utils import CaptureQueriesContext
+
+    with CaptureQueriesContext(connection) as ctx:
+        resp = client.get(url, params or {})
+    assert resp.status_code == 200
+    return len(ctx)
+
+
+@pytest.mark.django_db
+def test_api_query_count_is_independent_of_row_count(logged_in_client, printer):
+    """Every field the serializer reads must be in .only(), or Django emits one
+    extra SELECT per row per missing field — making query count scale with data."""
+    today = timezone.localtime().date()
+    url = reverse("bambu_run:printer_api")
+    params = {
+        "start_date": str(today - timedelta(days=1)),
+        "end_date": str(today),
+        "start_time": "00:00",
+        "end_time": "23:59",
+    }
+
+    _make_metrics(printer, 10)
+    few = _count_queries(logged_in_client, url, params)
+
+    _make_metrics(printer, 190)
+    many = _count_queries(logged_in_client, url, params)
+
+    assert few == many, f"query count scales with rows: {few} -> {many}"
+
+
+@pytest.mark.django_db
+def test_api_returns_dual_nozzle_values(logged_in_client, printer):
+    """The left-nozzle fields must survive the .only() narrowing."""
+    _make_metrics(printer, 5)
+    today = timezone.localtime().date()
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_api"),
+        {
+            "start_date": str(today - timedelta(days=1)),
+            "end_date": str(today),
+            "start_time": "00:00",
+            "end_time": "23:59",
+        },
+    )
+
+    data = resp.json()
+    assert any(v is not None for v in data["nozzle_temp_left"])
+    assert any(v is not None for v in data["nozzle_target_temp_left"])
+
+
+# --- Root cause: unbounded query when date params are missing ----------------
+
+
+@pytest.mark.django_db
+def test_api_without_params_is_time_bounded(logged_in_client, printer):
+    """A bare API call must not scan the whole table — it defaults to 24h."""
+    _make_metrics(printer, 10, spacing_seconds=30)  # inside 24h
+    old = PrinterMetrics.objects.create(
+        device=printer, timestamp=timezone.now() - timedelta(days=30), nozzle_temp=100
+    )
+
+    resp = logged_in_client.get(reverse("bambu_run:printer_api"))
+
+    data = resp.json()
+    assert len(data["timestamps"]) == 10
+    assert old.timestamp.isoformat() not in data["timestamps_iso"]
+
+
+@pytest.mark.django_db
+def test_api_with_only_start_date_is_time_bounded(logged_in_client, printer):
+    """Partial params must not drop the upper bound and scan forever."""
+    _make_metrics(printer, 5)
+    today = timezone.localtime().date()
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_api"), {"start_date": str(today - timedelta(days=1))}
+    )
+
+    assert resp.status_code == 200
+    assert len(resp.json()["timestamps"]) == 5
+
+
+@pytest.mark.django_db
+def test_api_downsamples_above_max_chart_points(logged_in_client, printer, monkeypatch):
+    monkeypatch.setattr("bambu_run.views._MAX_CHART_POINTS", 10)
+    _make_metrics(printer, 40, snapshots_per_metric=1, spacing_seconds=30)
+    today = timezone.localtime().date()
+
+    resp = logged_in_client.get(
+        reverse("bambu_run:printer_api"),
+        {
+            "start_date": str(today - timedelta(days=1)),
+            "end_date": str(today),
+            "start_time": "00:00",
+            "end_time": "23:59",
+        },
+    )
+
+    assert 0 < len(resp.json()["timestamps"]) <= 10
+
+
+# --- Root cause 2: the dashboard render -------------------------------------
+
+
+@pytest.mark.django_db
+def test_dashboard_query_count_is_independent_of_row_count(logged_in_client, printer):
+    url = reverse("bambu_run:printer_dashboard")
+
+    _make_metrics(printer, 10)
+    few = _count_queries(logged_in_client, url)
+
+    _make_metrics(printer, 190)
+    many = _count_queries(logged_in_client, url)
+
+    assert few == many, f"query count scales with rows: {few} -> {many}"
+
+
+@pytest.mark.django_db
+def test_dashboard_downsamples_chart_payload(logged_in_client, printer, monkeypatch):
+    """The dashboard inlines its JSON into the HTML, so it must sample like the API."""
+    monkeypatch.setattr("bambu_run.views._MAX_CHART_POINTS", 10)
+    _make_metrics(printer, 60, snapshots_per_metric=1)
+
+    resp = logged_in_client.get(reverse("bambu_run:printer_dashboard"))
+    payload = json.loads(resp.context["printer_data_json"])
+
+    assert 0 < len(payload["timestamps"]) <= 10
+
+
+@pytest.mark.django_db
+def test_dashboard_stats_use_the_newest_metric(logged_in_client, printer):
+    """Sampling must never drop the latest reading — the stat cards depend on it."""
+    import zoneinfo
+
+    from bambu_run.conf import app_settings
+
+    _make_metrics(printer, 20)
+    newest = PrinterMetrics.objects.create(
+        device=printer, timestamp=timezone.now(), nozzle_temp=242, gcode_state="RUNNING"
+    )
+
+    resp = logged_in_client.get(reverse("bambu_run:printer_dashboard"))
+
+    assert resp.context["stats"]["nozzle_temp"] == pytest.approx(242)
+    assert resp.context["stats"]["timestamp"] == newest.timestamp.astimezone(
+        zoneinfo.ZoneInfo(app_settings.TIMEZONE)
+    ).strftime("%Y-%m-%d %H:%M:%S")
+
+
+@pytest.mark.django_db
+def test_dashboard_filament_timeline_aligns_with_timestamps(logged_in_client, printer):
+    """remain_data must stay index-aligned with timestamps after sampling."""
+    _make_metrics(printer, 30, snapshots_per_metric=2)
+
+    resp = logged_in_client.get(reverse("bambu_run:printer_dashboard"))
+    payload = json.loads(resp.context["printer_data_json"])
+
+    n = len(payload["timestamps"])
+    assert payload["filament_timeline"]
+    for series in payload["filament_timeline"].values():
+        assert len(series["remain_data"]) == n