From 2ce52d9eab27e528a0bcca0f90607485f0b53921 Mon Sep 17 00:00:00 2001
From: Colin Maudry <colin@maudry.com>
Date: Fri, 10 Jul 2026 08:00:59 +0200
Subject: [PATCH] feat(grid): fetch_grid_page datasource server-side AG Grid
 (#41)

---
 src/utils/grid.py  | 34 ++++++++++++++++++++++++++++++++++
 tests/test_grid.py | 24 ++++++++++++++++++++++++
 2 files changed, 58 insertions(+)
 create mode 100644 src/utils/grid.py
 create mode 100644 tests/test_grid.py

diff --git a/src/utils/grid.py b/src/utils/grid.py
new file mode 100644
index 0000000..674b11c
--- /dev/null
+++ b/src/utils/grid.py
@@ -0,0 +1,34 @@
+"""Datasource server-side pour AG Grid (infinite row model)."""
+
+from src.db import count_marches, query_marches, schema
+from src.utils.query_ast import ast_to_sql, filtermodel_to_ast, sort_model_to_sql
+from src.utils.table import postprocess_page
+
+
+def fetch_grid_page(
+    filter_model,
+    sort_model,
+    start_row: int,
+    end_row: int,
+    base_where_sql: str = "TRUE",
+    base_params: tuple = (),
+) -> tuple[list[dict], int]:
+    """Renvoie (row_data, total_count) pour un bloc [start_row, end_row)."""
+    ast = filtermodel_to_ast(filter_model, schema)
+    filter_sql, filter_params = ast_to_sql(ast, schema)
+    where_sql = f"({base_where_sql}) AND ({filter_sql})"
+    params = [*base_params, *filter_params]
+
+    order_by = sort_model_to_sql(sort_model, schema) or None
+    total = count_marches(where_sql, params)
+
+    limit = max(0, end_row - start_row)
+    page = query_marches(
+        where_sql=where_sql,
+        params=params,
+        order_by=order_by,
+        limit=limit,
+        offset=start_row,
+    )
+    page = postprocess_page(page)
+    return page.to_dicts(), total
diff --git a/tests/test_grid.py b/tests/test_grid.py
new file mode 100644
index 0000000..22020be
--- /dev/null
+++ b/tests/test_grid.py
@@ -0,0 +1,24 @@
+from src.utils.grid import fetch_grid_page
+
+
+def test_fetch_grid_page_returns_rows_and_count():
+    rows, total = fetch_grid_page(None, None, 0, 20)
+    assert isinstance(rows, list)
+    assert isinstance(total, int)
+    assert total >= len(rows)
+    if rows:
+        # postprocess_page ajoute une colonne 'marche' avec un lien
+        assert "marche" in rows[0]
+
+
+def test_fetch_grid_page_filter_reduces_count():
+    _, total_all = fetch_grid_page(None, None, 0, 1)
+    fm = {"objet": {"filterType": "text", "type": "contains", "filter": "zzzzzznope"}}
+    rows, total_filtered = fetch_grid_page(fm, None, 0, 20)
+    assert total_filtered <= total_all
+    assert rows == [] and total_filtered == 0
+
+
+def test_fetch_grid_page_offset_slicing():
+    rows, _ = fetch_grid_page(None, None, 0, 5)
+    assert len(rows) <= 5