Ripristino delle quote già misurate nel ciclo in corso dopo un reload (#40)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/backend/services/measurement_service.py

@@ -9,6 +9,7 @@ from sqlalchemy import func, select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from src.backend.models.orm.measurement import Measurement
+from src.backend.models.orm.production import ProductionEvent
 from src.backend.models.orm.recipe import Recipe, RecipeVersion
 from src.backend.models.orm.task import (
     MEASURING_TASK_TYPES, RecipeSubtask, RecipeTask,
@@ -241,6 +242,73 @@ async def task_progress(
     return progress
 
 
+async def current_cycle_measurements(
+    db: AsyncSession, run_id: int, task_id: int,
+) -> list[dict]:
+    """The quotes of a task already measured in the cycle that is under way.
+
+    A reload, a timer redirect or an auto-logout throws away what the page held in
+    memory; the operator would measure the same quotes again and the duplicates
+    would reach the SPC statistics. The cycle needs no column of its own: it starts
+    at the latest event of the run that opens one for this task - the run start, a
+    cycle_completed, or a remeasure of this task.
+
+    If a task_measured of this task follows that boundary the task is already
+    closed in this cycle and there is nothing to restore. Where a quote was measured
+    more than once, the last reading stands.
+    """
+    boundary = (await db.execute(
+        select(ProductionEvent.id, ProductionEvent.created_at)
+        .where(
+            ProductionEvent.run_id == run_id,
+            (ProductionEvent.event_type.in_(("start", "cycle_completed")))
+            | (
+                (ProductionEvent.event_type == "remeasure")
+                & (ProductionEvent.task_id == task_id)
+            ),
+        )
+        .order_by(ProductionEvent.id.desc())
+        .limit(1)
+    )).first()
+
+    event_filter = [ProductionEvent.run_id == run_id]
+    measurement_filter = [Measurement.production_run_id == run_id]
+    if boundary is not None:
+        boundary_id, boundary_at = boundary
+        event_filter.append(ProductionEvent.id > boundary_id)
+        measurement_filter.append(Measurement.measured_at > boundary_at)
+
+    closed = (await db.execute(
+        select(ProductionEvent.id).where(
+            *event_filter,
+            ProductionEvent.event_type == "task_measured",
+            ProductionEvent.task_id == task_id,
+        ).limit(1)
+    )).first()
+    if closed is not None:
+        return []
+
+    rows = (await db.execute(
+        select(Measurement)
+        .join(RecipeSubtask, RecipeSubtask.id == Measurement.subtask_id)
+        .where(*measurement_filter, RecipeSubtask.task_id == task_id)
+        .order_by(Measurement.measured_at, Measurement.id)
+    )).scalars().all()
+
+    latest: dict[int, Measurement] = {}
+    for m in rows:
+        latest[m.subtask_id] = m
+    return [
+        {
+            "subtask_id": m.subtask_id,
+            "value": float(m.value),
+            "pass_fail": m.pass_fail,
+            "measured_at": m.measured_at,
+        }
+        for m in sorted(latest.values(), key=lambda m: (m.measured_at, m.id))
+    ]
+
+
 async def validate_run_for_version(
     db: AsyncSession, run_id: int, version_id: int,
 ) -> "ProductionRun":