change section collection

app/views/book/section.py

@@ -133,16 +133,47 @@ def section_delete(
 def change_section_position(book_id: int, section_id: int):
     section: m.Section = db.session.get(m.Section, section_id)
     new_position = request.json.get("position")
+    collection_id = request.json.get("collection_id")
 
-    sections_to_edit = m.Section.query.filter(
+    collection: m.Collection = section.collection
-        m.Section.collection_id == section.collection.id,
+    if collection_id is not None:
-        m.Section.position >= new_position,
+        collection: m.Collection = db.session.get(m.Collection, collection_id)
-    ).all()
+        if not collection:
-    for child in sections_to_edit:
+            log(log.INFO, "Collection with id [%s] not found", collection_id)
-        child: m.Section
+            return {"message": "collection not found"}, 404
-        if child.position >= new_position:
+
-            child.position += 1
+        log(
-            child.save(False)
+            log.INFO,
-    section.position = new_position
+            "Change section [%s] collection_id to [%s]",
+            section,
+            collection_id,
+        )
+        section.collection_id = collection_id
+
+    if collection.active_sections:
+        sections_to_edit = m.Section.query.filter(
+            m.Section.collection_id == collection.id,
+            m.Section.position >= new_position,
+        ).all()
+        if sections_to_edit:
+            log(log.INFO, "Calculate new positions of sections in [%s]", collection)
+            for child in sections_to_edit:
+                child: m.Section
+                if child.position >= new_position:
+                    child.position += 1
+                    child.save(False)
+
+        log(log.INFO, "Set new position [%s] of section [%s]", new_position, section)
+        section.position = new_position
+    else:
+        log(
+            log.INFO,
+            "Collection [%s] does not have active sections. Set section [%s] position to 1",
+            collection,
+            section,
+        )
+        section.position = 1
+
+    log(log.INFO, "Apply position changes on [%s]", section)
     section.save()
     return {}

tests/test_ordering.py

@@ -79,10 +79,12 @@ def test_change_section_ordering(client):
     root_collection = m.Collection.query.filter_by(is_root=True).first()
     assert root_collection
     assert root_collection.is_root
+    collection_1, _ = create_sub_collection(client, book.id, root_collection.id)
+    collection_2, _ = create_sub_collection(client, book.id, root_collection.id)
 
     current_ordering = {}  # collection_id : position
     for position in range(0, 10):
-        section, _ = create_section(client, book.id, root_collection.id)
+        section, _ = create_section(client, book.id, collection_1.id)
         assert section.position == position
         current_ordering[section.id] = section.position
 
@@ -92,9 +94,7 @@ def test_change_section_ordering(client):
     response: Response = client.post(
         f"/book/{book.id}/{section.id}/section/change_position",
         headers={"Content-Type": "application/json"},
-        json=dict(
+        json=dict(position=new_position),
-            position=new_position,
-        ),
         follow_redirects=True,
     )
 
@@ -102,8 +102,28 @@ def test_change_section_ordering(client):
     section: m.Section = db.session.get(m.Section, 3)
     assert current_ordering[section.id] != section.position
     assert section.position == new_position
-    for section in m.Section.query.filter_by(collection_id=root_collection.id).all():
+    for section in m.Section.query.filter_by(collection_id=collection_1.id).all():
         if section.position < new_position:
             assert current_ordering[section.id] == section.position
         elif section.position > new_position:
             assert current_ordering[section.id] + 1 == section.position
+
+    new_position = 999
+    assert section.collection_id == collection_1.id
+    assert not len(collection_2.active_sections)
+    response: Response = client.post(
+        f"/book/{book.id}/{section.id}/section/change_position",
+        headers={"Content-Type": "application/json"},
+        json=dict(position=new_position, collection_id=collection_2.id),
+        follow_redirects=True,
+    )
+    assert response.status_code == 200
+
+    section: m.Section = db.session.get(m.Section, section.id)
+    assert section.collection_id != collection_1.id
+    assert section.collection_id == collection_2.id
+
+    collection: m.Collection = section.collection
+    assert len(collection.active_sections) == 1
+    assert section.position != new_position
+    assert section.position == 1