From 53cc90a74bbdd7b1a7262e0dd7db0bf819f5cce0 Mon Sep 17 00:00:00 2001
From: Yaro Kasear <git@kasear.net>
Date: Tue, 7 Oct 2025 10:28:11 -0500
Subject: [PATCH] Fix paging.

---
 crudkit/core/service.py | 36 ++++++++++++++++++++++++++++--------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/crudkit/core/service.py b/crudkit/core/service.py
index e9484da..38b7e31 100644
--- a/crudkit/core/service.py
+++ b/crudkit/core/service.py
@@ -205,22 +205,42 @@ class CRUDService(Generic[T]):
         # Make sure joins/filters match the real query
         query = self._apply_firsthop_strategies(query, root_alias, plan)
         if plan.filters:
-            query = query.filters(*plan.filters)
+            query = query.filter(*plan.filters)
 
         order_spec = self._extract_order_spec(root_alias, plan.order_by)
-        query = query.order_by(*self._order_clauses(order_spec, invert=False))
 
-        # We only need the order-by columns for the anchor
-        anchor_q = self.session.query(*order_spec.cols)
-        # IMPORTANT: anchor_q must use the same FROMs/joins as `query`
-        anchor_q = anchor_q.select_from(query.subquery())
+        # Inner subquery must be ordered exactly like the real query
+        inner = query.order_by(*self._order_clauses(order_spec, invert=False))
+
+        # IMPORTANT: Build subquery that actually exposes the order-by columns
+        # under predictable names, then select FROM that and reference subq.c[...]
+        subq = inner.with_entities(*order_spec.cols).subquery()
+
+        # Map the order columns to the subquery columns by key/name
+        cols_on_subq = []
+        for col in order_spec.cols:
+            key = getattr(col, "key", None) or getattr(col, "name", None)
+            if not key:
+                # Fallback, but frankly your order cols should have names
+                raise ValueError("Order-by column is missing a key/name")
+            cols_on_subq.append(getattr(subq.c, key))
+
+        # Now the outer anchor query orders and offsets on the subquery columns
+        anchor_q = (
+            self.session
+            .query(*cols_on_subq)
+            .select_from(subq)
+            .order_by(*[
+                (c.desc() if is_desc else c.asc())
+                for c, is_desc in zip(cols_on_subq, order_spec.desc)
+            ])
+        )
 
         offset = max(0, (page - 1) * per_page - 1)
         row = anchor_q.offset(offset).limit(1).first()
         if not row:
             return None
-        # Row might be a tuple-like; turn into list for _key_predicate
-        return list(row)
+        return list(row)  # tuple-like -> list for _key_predicate
 
     def _apply_not_deleted(self, query, root_alias, params):
         if self.supports_soft_delete and not _is_truthy((params or {}).get("include_deleted")):