inital commit

booking/services.py

@@ -0,0 +1,159 @@
+from decimal import Decimal
+from datetime import timezone as dt_timezone
+
+from django.core.exceptions import ValidationError
+from django.db.models import Q
+from django.utils import timezone
+
+from .models import AvailabilitySlot, Booking, BookingEventLog
+
+ACTIVE_BOOKING_STATUSES = [Booking.Status.REQUESTED, Booking.Status.APPROVED, Booking.Status.CONFIRMED]
+
+
+def _normalize_utc(dt):
+    if timezone.is_naive(dt):
+        raise ValidationError("Datetime values must include timezone information (UTC ISO-8601).")
+    return dt.astimezone(dt_timezone.utc)
+
+
+def is_bookable(*, equipment_item=None, adventure_offering=None, starts_at, ends_at, exclude_booking_id=None):
+    starts_at = _normalize_utc(starts_at)
+    ends_at = _normalize_utc(ends_at)
+    if starts_at >= ends_at:
+        return False
+
+    filters = Q(starts_at__lt=ends_at, ends_at__gt=starts_at, status__in=ACTIVE_BOOKING_STATUSES)
+    if equipment_item is not None:
+        filters &= Q(equipment_item=equipment_item)
+    elif adventure_offering is not None:
+        filters &= Q(adventure_offering=adventure_offering)
+    else:
+        return False
+
+    queryset = Booking.objects.filter(filters)
+    if exclude_booking_id is not None:
+        queryset = queryset.exclude(id=exclude_booking_id)
+    has_overlap = queryset.exists()
+    if has_overlap:
+        return False
+
+    slot_filters = Q(starts_at__lt=ends_at, ends_at__gt=starts_at)
+    if equipment_item is not None:
+        slot_filters &= Q(equipment_item=equipment_item)
+    else:
+        slot_filters &= Q(adventure_offering=adventure_offering)
+
+    target_slots = AvailabilitySlot.objects.filter(slot_filters)
+    if not target_slots.exists():
+        # If no slot schedule exists yet, keep backward-compatible "bookable by default" behavior.
+        return True
+
+    has_blocking_unavailable = target_slots.filter(is_available=False).exists()
+    if has_blocking_unavailable:
+        return False
+
+    has_covering_available_slot = target_slots.filter(is_available=True, starts_at__lte=starts_at, ends_at__gte=ends_at).exists()
+    return has_covering_available_slot
+
+
+def quote_booking(*, equipment_item=None, adventure_offering=None, starts_at, ends_at, participants_count=1):
+    starts_at = _normalize_utc(starts_at)
+    ends_at = _normalize_utc(ends_at)
+    if ends_at <= starts_at:
+        raise ValidationError("ends_at must be greater than starts_at.")
+    if starts_at < timezone.now():
+        raise ValidationError("starts_at must be in the future.")
+
+    if equipment_item is not None and adventure_offering is not None:
+        raise ValidationError("Only one target can be quoted at a time.")
+    if equipment_item is None and adventure_offering is None:
+        raise ValidationError("A booking target is required.")
+
+    if equipment_item is not None:
+        duration_days = (ends_at - starts_at).total_seconds() / 86400
+        billable_days = max(1, int(duration_days) if duration_days.is_integer() else int(duration_days) + 1)
+        return Decimal(billable_days) * equipment_item.price_per_day
+
+    if participants_count < 1:
+        raise ValidationError("participants_count must be at least 1.")
+    if participants_count > adventure_offering.capacity:
+        raise ValidationError("participants_count exceeds adventure capacity.")
+    return Decimal(participants_count) * adventure_offering.price_per_person
+
+
+def create_booking_request(
+    *,
+    customer,
+    starts_at,
+    ends_at,
+    equipment_item=None,
+    adventure_offering=None,
+    customer_notes="",
+    participants_count=1,
+    listing_click=None,
+):
+    starts_at = _normalize_utc(starts_at)
+    ends_at = _normalize_utc(ends_at)
+    if not is_bookable(
+        equipment_item=equipment_item,
+        adventure_offering=adventure_offering,
+        starts_at=starts_at,
+        ends_at=ends_at,
+    ):
+        raise ValidationError("This item/offering is not available for this range.")
+
+    total_price = quote_booking(
+        equipment_item=equipment_item,
+        adventure_offering=adventure_offering,
+        starts_at=starts_at,
+        ends_at=ends_at,
+        participants_count=participants_count,
+    )
+
+    vendor = equipment_item.vendor if equipment_item else adventure_offering.vendor
+    booking = Booking.objects.create(
+        customer=customer,
+        vendor=vendor,
+        equipment_item=equipment_item,
+        adventure_offering=adventure_offering,
+        starts_at=starts_at,
+        ends_at=ends_at,
+        status=Booking.Status.REQUESTED,
+        total_price=total_price,
+        customer_notes=customer_notes,
+        listing_click=listing_click,
+    )
+    BookingEventLog.objects.create(
+        booking=booking,
+        from_status="",
+        to_status=Booking.Status.REQUESTED,
+        note="Booking requested.",
+        actor=customer,
+    )
+    return booking
+
+
+def transition_booking_status(*, booking, to_status, actor, note="", vendor_notes=None):
+    allowed_transitions = {
+        Booking.Status.REQUESTED: {Booking.Status.APPROVED, Booking.Status.DECLINED, Booking.Status.CANCELLED},
+        Booking.Status.APPROVED: {Booking.Status.CONFIRMED, Booking.Status.CANCELLED},
+        Booking.Status.CONFIRMED: {Booking.Status.CANCELLED},
+        Booking.Status.DECLINED: set(),
+        Booking.Status.CANCELLED: set(),
+    }
+    current = booking.status
+    if to_status not in allowed_transitions[current]:
+        raise ValidationError(f"Invalid booking status transition: {current} -> {to_status}")
+
+    booking.status = to_status
+    if vendor_notes is not None:
+        booking.vendor_notes = vendor_notes
+    booking.save(update_fields=["status", "vendor_notes", "updated_at"])
+    BookingEventLog.objects.create(
+        booking=booking,
+        from_status=current,
+        to_status=to_status,
+        note=note,
+        actor=actor,
+    )
+    return booking