Allow multiple projects/categories/lab priorities per entry

apps/audit/signals.py

@@ -8,7 +8,7 @@
 from .service import log_event
 
 _TRACKED_FIELDS = (
-    'title', 'project_id', 'category_id', 'entry_type_id', 'group_id',
+    'title', 'entry_type_id', 'group_id',
     'period_kind', 'period_start', 'period_end',
     'description', 'is_private', 'is_critical', 'is_highlight', 'highlight_stars',
     'is_division_head_only', 'author_id', 'is_archived',
@@ -92,6 +92,43 @@ def _workitem_tags_changed(sender, instance, action, pk_set, **kwargs):
         log_event(action='update', obj=instance, changes={'tags_cleared': True})
 
 
+# ── WorkItem taxonomy m2m changes (projects / categories / lab priorities) ────
+
+def _log_taxonomy_m2m(instance, action, pk_set, model, label):
+    if action not in ('post_add', 'post_remove', 'post_clear'):
+        return
+    if not isinstance(instance, WorkItem):
+        return  # guard: m2m_changed fires for both sides of the relation
+    if action == 'post_add' and pk_set:
+        names = sorted(model.objects.filter(pk__in=pk_set).values_list('name', flat=True))
+        if names:
+            log_event(action='update', obj=instance, changes={f'{label}_added': names})
+    elif action == 'post_remove' and pk_set:
+        names = sorted(model.objects.filter(pk__in=pk_set).values_list('name', flat=True))
+        if names:
+            log_event(action='update', obj=instance, changes={f'{label}_removed': names})
+    elif action == 'post_clear':
+        log_event(action='update', obj=instance, changes={f'{label}_cleared': True})
+
+
+@receiver(m2m_changed, sender=WorkItem.projects.through)
+def _workitem_projects_changed(sender, instance, action, pk_set, **kwargs):
+    from apps.taxonomy.models import Project
+    _log_taxonomy_m2m(instance, action, pk_set, Project, 'projects')
+
+
+@receiver(m2m_changed, sender=WorkItem.categories.through)
+def _workitem_categories_changed(sender, instance, action, pk_set, **kwargs):
+    from apps.taxonomy.models import Category
+    _log_taxonomy_m2m(instance, action, pk_set, Category, 'categories')
+
+
+@receiver(m2m_changed, sender=WorkItem.lab_priorities.through)
+def _workitem_lab_priorities_changed(sender, instance, action, pk_set, **kwargs):
+    from apps.taxonomy.models import LabPriority
+    _log_taxonomy_m2m(instance, action, pk_set, LabPriority, 'lab_priorities')
+
+
 # ── Auth events ───────────────────────────────────────────────────────────────
 
 @receiver(user_logged_in)

apps/core/templates/core/api.html

@@ -59,13 +59,13 @@ <h2 class="text-base font-semibold text-blue-900">REST API</h2>
                 <pre class="bg-slate-50 border border-slate-200 rounded p-3 text-slate-700 overflow-x-auto leading-relaxed">{
   "title":        "string (required)",
   "description":  "string (required)",
-  "project":      "slug or id (required)",
-  "category":     "slug or id (required)",
+  "projects":     ["slug or id", …]  (required; accepts a single value too),
+  "categories":   ["slug or id", …]  (required; accepts a single value too),
   "period_kind":  "today|week|fortnight|month|custom",
   "period_start": "YYYY-MM-DD (required)",
   "period_end":   "YYYY-MM-DD (required)",
   "group":        "slug or id (optional)",
-  "lab_priority": "slug or id (optional)",
+  "lab_priorities": ["slug or id", …]  (optional),
   "tags":         ["tag1", "tag2"],
   "is_private":           false,
   "is_critical":          false,
@@ -79,8 +79,10 @@ <h2 class="text-base font-semibold text-blue-900">REST API</h2>
                 <pre class="bg-slate-50 border border-slate-200 rounded p-3 text-slate-700 overflow-x-auto leading-relaxed">{
   "id":           42,
   "title":        "Weekly status",
-  "project":      "project-slug",
-  "category":     "category-slug",
+  "projects":     ["project-slug"],
+  "categories":   ["category-slug"],
+  "project":      "project-slug",   (legacy: first selected)
+  "category":     "category-slug",  (legacy: first selected)
   "period_kind":  "week",
   "period_start": "2026-05-26",
   "period_end":   "2026-06-01",

apps/core/templates/core/dashboard.html

@@ -54,7 +54,7 @@ <h2 class="font-semibold text-slate-800">Recent Entries</h2>
             <a href="{% url 'entries:detail' entry.pk %}"
                class="text-sm font-medium text-slate-800 hover:text-scd-primary truncate block">{{ entry.title }}</a>
             <p class="text-xs text-slate-400 mt-0.5">
-              {{ entry.project.name }} · {{ entry.category.name }} ·
+              {% for p in entry.projects.all %}{{ p.name }}{% if not forloop.last %}, {% endif %}{% endfor %} · {% for c in entry.categories.all %}{{ c.name }}{% if not forloop.last %}, {% endif %}{% endfor %} ·
               {{ entry.period_start|date:"M j" }}–{{ entry.period_end|date:"M j, Y" }}
             </p>
           </div>

apps/core/views.py

@@ -51,8 +51,7 @@ def get_context_data(self, **kwargs):
         ctx['recent_entries'] = (
             WorkItem.objects
             .filter(author=self.request.user)
-            .select_related('project', 'category')
-            .prefetch_related('tags')
+            .prefetch_related('projects', 'categories', 'tags')
             .order_by('-period_end', '-created_at')[:20]
         )
         ctx['prompt_form'] = AIPromptConfigForm(instance=AIPromptConfig.for_user(self.request.user))
@@ -71,8 +70,8 @@ def post(self, request):
             })
         qs = (WorkItem.objects
               .filter(author=request.user, pk__in=selected_ids)
-              .select_related('author', 'project', 'category')
-              .prefetch_related('tags'))
+              .select_related('author')
+              .prefetch_related('projects', 'categories', 'tags'))
         count = qs.count()
         if count == 0:
             return render(request, 'core/partials/_dashboard_summary.html', {

apps/entries/admin.py

@@ -5,11 +5,19 @@
 
 @admin.register(WorkItem)
 class WorkItemAdmin(admin.ModelAdmin):
-    list_display = ('title', 'author', 'project', 'category', 'entry_type',
+    list_display = ('title', 'author', 'projects_list', 'categories_list', 'entry_type',
                     'period_start', 'period_end', 'is_private', 'created_at')
-    list_filter = ('project', 'category', 'entry_type', 'is_private')
+    list_filter = ('projects', 'categories', 'entry_type', 'is_private')
     search_fields = ('title', 'description', 'author__email', 'author__display_name')
     raw_id_fields = ('author',)
-    filter_horizontal = ('tags',)
+    filter_horizontal = ('projects', 'categories', 'lab_priorities', 'tags')
     date_hierarchy = 'period_start'
     readonly_fields = ('created_at', 'updated_at')
+
+    @admin.display(description='Projects')
+    def projects_list(self, obj):
+        return ', '.join(p.name for p in obj.projects.all())
+
+    @admin.display(description='Categories')
+    def categories_list(self, obj):
+        return ', '.join(c.name for c in obj.categories.all())

apps/entries/api_views.py

@@ -51,6 +51,33 @@ def _resolve_fk(model, value, allow_blank=False):
         return None, f'{model.__name__} "{value}" not found or inactive.'
 
 
+def _resolve_fk_list(model, value, required=True):
+    """Resolve a slug/PK or list of them to a list of instances.
+
+    Accepts a single value (backward-compatible) or a list. Returns
+    (list_of_instances, error_str).
+    """
+    if value in (None, '', []):
+        if required:
+            return None, f'{model.__name__} is required.'
+        return [], None
+    values = value if isinstance(value, list) else [value]
+    instances = []
+    for v in values:
+        inst, err = _resolve_fk(model, v)
+        if err:
+            return None, err
+        instances.append(inst)
+    return instances, None
+
+
+def _get_multi(data, plural_key, singular_key):
+    """Read a list field, preferring the plural key but accepting the legacy singular one."""
+    if plural_key in data:
+        return data[plural_key]
+    return data.get(singular_key)
+
+
 def _coerce_bool(val, default=False):
     if isinstance(val, bool):
         return val
@@ -120,21 +147,23 @@ def post(self, request):
         if parsed_start and parsed_end and parsed_end < parsed_start:
             errors['period_end'] = 'period_end must be on or after period_start.'
 
-        project, err = _resolve_fk(Project, data.get('project'))
+        projects, err = _resolve_fk_list(Project, _get_multi(data, 'projects', 'project'))
         if err:
-            errors['project'] = err
+            errors['projects'] = err
 
-        category, err = _resolve_fk(Category, data.get('category'))
+        categories, err = _resolve_fk_list(Category, _get_multi(data, 'categories', 'category'))
         if err:
-            errors['category'] = err
+            errors['categories'] = err
 
         group, err = _resolve_fk(WorkGroup, data.get('group'), allow_blank=True)
         if err:
             errors['group'] = err
 
-        lab_priority, err = _resolve_fk(LabPriority, data.get('lab_priority'), allow_blank=True)
+        lab_priorities, err = _resolve_fk_list(
+            LabPriority, _get_multi(data, 'lab_priorities', 'lab_priority'), required=False,
+        )
         if err:
-            errors['lab_priority'] = err
+            errors['lab_priorities'] = err
 
         if errors:
             return JsonResponse({'errors': errors}, status=400)
@@ -144,10 +173,7 @@ def post(self, request):
                 author=user,
                 title=title,
                 description=description,
-                project=project,
-                category=category,
                 group=group,
-                lab_priority=lab_priority,
                 period_kind=period_kind,
                 period_start=parsed_start,
                 period_end=parsed_end,
@@ -157,6 +183,9 @@ def post(self, request):
                 highlight_stars=_coerce_int(data.get('highlight_stars')),
                 is_division_head_only=_coerce_bool(data.get('is_division_head_only')),
             )
+            entry.projects.set(projects)
+            entry.categories.set(categories)
+            entry.lab_priorities.set(lab_priorities)
 
             tag_names = data.get('tags', [])
             if isinstance(tag_names, list):
@@ -171,11 +200,16 @@ def post(self, request):
                     entry.tags.set(tags)
 
         from django.urls import reverse
+        project_slugs = [p.slug for p in projects]
+        category_slugs = [c.slug for c in categories]
         return JsonResponse({
             'id': entry.pk,
             'title': entry.title,
-            'project': entry.project.slug,
-            'category': entry.category.slug,
+            'projects': project_slugs,
+            'categories': category_slugs,
+            # Legacy single-value keys (first selected) for backward compatibility.
+            'project': project_slugs[0] if project_slugs else None,
+            'category': category_slugs[0] if category_slugs else None,
             'period_kind': entry.period_kind,
             'period_start': entry.period_start.isoformat(),
             'period_end': entry.period_end.isoformat(),

apps/entries/forms.py

@@ -12,7 +12,7 @@ class WorkItemForm(forms.ModelForm):
     class Meta:
         model = WorkItem
         fields = [
-            'title', 'project', 'category', 'entry_type', 'group', 'lab_priority',
+            'title', 'projects', 'categories', 'lab_priorities', 'entry_type', 'group',
             'period_kind', 'period_start', 'period_end',
             'description', 'is_private', 'is_critical', 'is_highlight', 'highlight_stars',
             'is_division_head_only',
@@ -27,15 +27,23 @@ class Meta:
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        self.fields['project'].queryset  = Project.objects.filter(is_active=True).order_by('sort_order', 'name')
-        self.fields['category'].queryset = Category.objects.filter(is_active=True).order_by('sort_order', 'name')
-        self.fields['entry_type'].queryset   = EntryType.objects.filter(is_active=True).order_by('sort_order', 'name')
-        self.fields['entry_type'].required   = False
-        self.fields['group'].queryset        = WorkGroup.objects.filter(is_active=True).order_by('sort_order', 'name')
-        self.fields['group'].required        = False
-        self.fields['lab_priority'].queryset = LabPriority.objects.filter(is_active=True).order_by('sort_order', 'name')
-        self.fields['lab_priority'].required = False
+        self.fields['projects'].queryset   = Project.objects.filter(is_active=True).order_by('sort_order', 'name')
+        self.fields['categories'].queryset = Category.objects.filter(is_active=True).order_by('sort_order', 'name')
+        # At least one project and one category remain required (ModelMultipleChoiceField
+        # is required by default — an empty multi-select fails validation).
+        self.fields['lab_priorities'].queryset = LabPriority.objects.filter(is_active=True).order_by('sort_order', 'name')
+        self.fields['lab_priorities'].required = False
+        self.fields['entry_type'].queryset = EntryType.objects.filter(is_active=True).order_by('sort_order', 'name')
+        self.fields['entry_type'].required = False
+        self.fields['group'].queryset      = WorkGroup.objects.filter(is_active=True).order_by('sort_order', 'name')
+        self.fields['group'].required      = False
         self.fields['highlight_stars'].required = False
+
+        # Style the multi-select widgets to match the rest of the form.
+        _multi_cls = ('w-full rounded-md border border-slate-300 px-3 py-2 text-sm shadow-sm '
+                      'focus:border-scd-primary focus:ring-1 focus:ring-scd-primary focus:outline-none')
+        for _name in ('projects', 'categories', 'lab_priorities'):
+            self.fields[_name].widget.attrs.update({'class': _multi_cls, 'size': 5})
         if self.instance.pk:
             self.fields['tags_input'].initial = ','.join(
                 self.instance.tags.values_list('name', flat=True)

apps/entries/migrations/0009_multiselect_taxonomy.py

@@ -0,0 +1,85 @@
+# Generated by Django 5.2.14 on 2026-06-25 17:36
+#
+# Converts WorkItem.project / category / lab_priority (single FKs) to
+# many-to-many relations (projects / categories / lab_priorities). The new
+# M2M fields are added first, existing single values are copied across, and
+# only then are the old FK columns removed — so no data is lost.
+
+from django.db import migrations, models
+
+
+def copy_fk_to_m2m(apps, schema_editor):
+    WorkItem = apps.get_model("entries", "WorkItem")
+    for item in WorkItem.objects.all():
+        if item.project_id:
+            item.projects.add(item.project_id)
+        if item.category_id:
+            item.categories.add(item.category_id)
+        if item.lab_priority_id:
+            item.lab_priorities.add(item.lab_priority_id)
+
+
+def copy_m2m_to_fk(apps, schema_editor):
+    # Reverse: collapse each M2M back to a single value (first by sort order).
+    WorkItem = apps.get_model("entries", "WorkItem")
+    for item in WorkItem.objects.all():
+        project = item.projects.first()
+        category = item.categories.first()
+        lab_priority = item.lab_priorities.first()
+        item.project = project
+        item.category = category
+        item.lab_priority = lab_priority
+        item.save(update_fields=["project", "category", "lab_priority"])
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("entries", "0008_workitem_entry_type_and_more"),
+        ("taxonomy", "0003_labpriority"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="workitem",
+            name="categories",
+            field=models.ManyToManyField(
+                related_name="work_items", to="taxonomy.category"
+            ),
+        ),
+        migrations.AddField(
+            model_name="workitem",
+            name="lab_priorities",
+            field=models.ManyToManyField(
+                blank=True, related_name="work_items", to="taxonomy.labpriority"
+            ),
+        ),
+        migrations.AddField(
+            model_name="workitem",
+            name="projects",
+            field=models.ManyToManyField(
+                related_name="work_items", to="taxonomy.project"
+            ),
+        ),
+        migrations.RunPython(copy_fk_to_m2m, copy_m2m_to_fk),
+        migrations.RemoveIndex(
+            model_name="workitem",
+            name="entries_wor_project_814625_idx",
+        ),
+        migrations.RemoveIndex(
+            model_name="workitem",
+            name="entries_wor_categor_3c98a4_idx",
+        ),
+        migrations.RemoveField(
+            model_name="workitem",
+            name="category",
+        ),
+        migrations.RemoveField(
+            model_name="workitem",
+            name="lab_priority",
+        ),
+        migrations.RemoveField(
+            model_name="workitem",
+            name="project",
+        ),
+    ]