Refactor grant reimbursement categories to be flexible

Remove hardcoded default grant amounts for ticket, accommodation, and travel
from `Conference` in favor of using `GrantReimbursementCategory`. Update
all relevant admin forms, models, and templates to reference flexible
categories instead of fixed fields.

- Remove legacy fields: `grants_default_ticket_amount`,
  `grants_default_accommodation_amount`, `grants_default_travel_from_italy_amount`,
  and `grants_default_travel_from_europe_amount` from `Conference`
- Update `Grant` and `GrantReimbursement` logic to work exclusively with
  `GrantReimbursementCategory`
- Refactor grant review admin and summary logic to support multiple,
  configurable reimbursement categories per grant
- Migrate existing grants to new reimbursement category scheme
- Add and update tests and migrations to cover flexible grant categories

This change allows flexible reimbursement types (and amounts) to be
configured per conference, supports granular grant allocation, and
paves the way for internationalization and more complex business rules.

Author: estyxx

backend/conferences/admin/conference.py

@@ -184,18 +184,6 @@ class ConferenceAdmin(
                 )
             },
         ),
-        (
-            "Grants",
-            {
-                "fields": (
-                    "grants_default_ticket_amount",
-                    "grants_default_accommodation_amount",
-                    "grants_default_travel_from_italy_amount",
-                    "grants_default_travel_from_europe_amount",
-                    "grants_default_travel_from_extra_eu_amount",
-                )
-            },
-        ),
         ("YouTube", {"fields": ("video_title_template", "video_description_template")}),
     )
     inlines = [DeadlineInline, DurationInline, SponsorLevelInline, IncludedEventInline]

backend/conferences/migrations/0055_remove_conference_grants_default_accommodation_amount_and_more.py

@@ -0,0 +1,33 @@
+# Generated by Django 5.1.4 on 2025-07-27 14:30
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('conferences', '0054_conference_frontend_revalidate_secret_and_more'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='conference',
+            name='grants_default_accommodation_amount',
+        ),
+        migrations.RemoveField(
+            model_name='conference',
+            name='grants_default_ticket_amount',
+        ),
+        migrations.RemoveField(
+            model_name='conference',
+            name='grants_default_travel_from_europe_amount',
+        ),
+        migrations.RemoveField(
+            model_name='conference',
+            name='grants_default_travel_from_extra_eu_amount',
+        ),
+        migrations.RemoveField(
+            model_name='conference',
+            name='grants_default_travel_from_italy_amount',
+        ),
+    ]

backend/conferences/models/conference.py

@@ -93,47 +93,6 @@ class Conference(GeoLocalizedModel, TimeFramedModel, TimeStampedModel):
         default="",
     )
 
-    grants_default_ticket_amount = models.DecimalField(
-        verbose_name=_("grants default ticket amount"),
-        null=True,
-        blank=True,
-        max_digits=6,
-        decimal_places=2,
-        default=None,
-    )
-    grants_default_accommodation_amount = models.DecimalField(
-        verbose_name=_("grants default accommodation amount"),
-        null=True,
-        blank=True,
-        max_digits=6,
-        decimal_places=2,
-        default=None,
-    )
-    grants_default_travel_from_italy_amount = models.DecimalField(
-        verbose_name=_("grants default travel from Italy amount"),
-        null=True,
-        blank=True,
-        max_digits=6,
-        decimal_places=2,
-        default=None,
-    )
-    grants_default_travel_from_europe_amount = models.DecimalField(
-        verbose_name=_("grants default travel from Europe amount"),
-        null=True,
-        blank=True,
-        max_digits=6,
-        decimal_places=2,
-        default=None,
-    )
-    grants_default_travel_from_extra_eu_amount = models.DecimalField(
-        verbose_name=_("grants default travel from Extra EU amount"),
-        null=True,
-        blank=True,
-        max_digits=6,
-        decimal_places=2,
-        default=None,
-    )
-
     video_title_template = models.TextField(
         default="",
         blank=True,

backend/grants/admin.py

@@ -1,45 +1,53 @@
 import logging
-from django.db import transaction
-from custom_admin.audit import (
-    create_addition_admin_log_entry,
-    create_change_admin_log_entry,
-)
-from conferences.models.conference_voucher import ConferenceVoucher
-from pycon.constants import UTC
-from custom_admin.admin import (
-    confirm_pending_status,
-    reset_pending_status_back_to_status,
-    validate_single_conference_selection,
-)
-from import_export.resources import ModelResource
 from datetime import timedelta
 from typing import Dict, List, Optional
-from countries.filters import CountryFilter
+
 from django.contrib import admin, messages
+from django.contrib.admin import SimpleListFilter
+from django.db import transaction
+from django.db.models import Exists, F, IntegerField, OuterRef, Sum, Value
+from django.db.models.functions import Coalesce
 from django.db.models.query import QuerySet
+from django.urls import reverse
 from django.utils import timezone
+from django.utils.safestring import mark_safe
 from import_export.admin import ExportMixin
 from import_export.fields import Field
-from users.admin_mixins import ConferencePermissionMixin
+from import_export.resources import ModelResource
+
+from conferences.models.conference_voucher import ConferenceVoucher
 from countries import countries
+from countries.filters import CountryFilter
+from custom_admin.admin import (
+    confirm_pending_status,
+    reset_pending_status_back_to_status,
+    validate_single_conference_selection,
+)
+from custom_admin.audit import (
+    create_addition_admin_log_entry,
+    create_change_admin_log_entry,
+)
 from grants.tasks import (
     send_grant_reply_approved_email,
+    send_grant_reply_rejected_email,
     send_grant_reply_waiting_list_email,
     send_grant_reply_waiting_list_update_email,
-    send_grant_reply_rejected_email,
 )
+from participants.models import Participant
+from pretix import user_has_admission_ticket
+from pycon.constants import UTC
 from schedule.models import ScheduleItem
 from submissions.models import Submission
-from .models import Grant, GrantConfirmPendingStatusProxy
-from django.db.models import Exists, OuterRef
-from pretix import user_has_admission_ticket
-
-from django.contrib.admin import SimpleListFilter
-from participants.models import Participant
-from django.urls import reverse
-from django.utils.safestring import mark_safe
+from users.admin_mixins import ConferencePermissionMixin
 from visa.models import InvitationLetterRequest
 
+from .models import (
+    Grant,
+    GrantConfirmPendingStatusProxy,
+    GrantReimbursement,
+    GrantReimbursementCategory,
+)
+
 logger = logging.getLogger(__name__)
 
 EXPORT_GRANTS_FIELDS = (
@@ -394,6 +402,32 @@ def queryset(self, request, queryset):
         return queryset
 
 
+@admin.register(GrantReimbursementCategory)
+class GrantReimbursementCategoryAdmin(ConferencePermissionMixin, admin.ModelAdmin):
+    list_display = ("__str__", "max_amount", "category", "included_by_default")
+    list_filter = ("conference", "category", "included_by_default")
+    search_fields = ("category", "name")
+
+
+@admin.register(GrantReimbursement)
+class GrantReimbursementAdmin(ConferencePermissionMixin, admin.ModelAdmin):
+    list_display = (
+        "grant",
+        "category",
+        "granted_amount",
+    )
+    list_filter = ("grant__conference", "category")
+    search_fields = ("grant__full_name", "grant__email")
+    autocomplete_fields = ("grant",)
+
+
+class GrantReimbursementInline(admin.TabularInline):
+    model = GrantReimbursement
+    extra = 0
+    autocomplete_fields = ["category"]
+    fields = ["category", "granted_amount"]
+
+
 @admin.register(Grant)
 class GrantAdmin(ExportMixin, ConferencePermissionMixin, admin.ModelAdmin):
     change_list_template = "admin/grants/grant/change_list.html"
@@ -407,11 +441,7 @@ class GrantAdmin(ExportMixin, ConferencePermissionMixin, admin.ModelAdmin):
         "emoji_gender",
         "conference",
         "status",
-        "approved_type",
-        "ticket_amount",
-        "travel_amount",
-        "accommodation_amount",
-        "total_amount",
+        "total_amount_display",
         "country_type",
         "user_has_ticket",
         "has_voucher",
@@ -425,7 +455,6 @@ class GrantAdmin(ExportMixin, ConferencePermissionMixin, admin.ModelAdmin):
         "pending_status",
         "country_type",
         "occupation",
-        "approved_type",
         "needs_funds_for_travel",
         "need_visa",
         "need_accommodation",
@@ -451,6 +480,7 @@ class GrantAdmin(ExportMixin, ConferencePermissionMixin, admin.ModelAdmin):
         "delete_selected",
     ]
     autocomplete_fields = ("user",)
+    inlines = [GrantReimbursementInline]
 
     fieldsets = (
         (
@@ -459,12 +489,7 @@ class GrantAdmin(ExportMixin, ConferencePermissionMixin, admin.ModelAdmin):
                 "fields": (
                     "status",
                     "pending_status",
-                    "approved_type",
                     "country_type",
-                    "ticket_amount",
-                    "travel_amount",
-                    "accommodation_amount",
-                    "total_amount",
                     "applicant_reply_sent_at",
                     "applicant_reply_deadline",
                     "internal_notes",
@@ -591,11 +616,22 @@ def has_sent_invitation_letter_request(self, obj: Grant) -> bool:
         if obj.has_invitation_letter_request:
             return "📧"
         return ""
+    @admin.display(description="Total")
+    def total_amount_display(self, obj):
+        return f"{obj.total_allocated:.2f}"
+
+    @admin.display(description="Approved Reimbursements")
+    def approved_amounts_display(self, obj):
+        return ", ".join(
+            f"{r.category.name}: {r.granted_amount}" for r in obj.reimbursements.all()
+        )
 
     def get_queryset(self, request):
         qs = (
             super()
             .get_queryset(request)
+            .select_related("user")
+            .prefetch_related("reimbursements__category")
             .annotate(
                 is_proposed_speaker=Exists(
                     Submission.objects.non_cancelled().filter(
@@ -622,6 +658,11 @@ def get_queryset(self, request):
                         requester_id=OuterRef("user_id"),
                     )
                 ),
+                total_allocated=Coalesce(
+                    Sum("reimbursements__granted_amount"),
+                    Value(0),
+                    output_field=IntegerField(),
+                ),
             )
         )