feat: planner hard-constraint filter for the 6 spec constraints

2026-05-06 06:42:49 -07:00
parent bf0a327561
commit 95396137c6
2 changed files with 275 additions and 0 deletions
@@ -0,0 +1,88 @@
+"""Hard-constraint filter (constraints #1-#6 from the spec)."""
+from __future__ import annotations
+
+from datetime import date, timedelta
+from typing import Dict, Iterable, List, Optional, Set
+from uuid import UUID
+
+from app.services.planner.config import PlannerConfig
+from app.services.planner.types import FilterResult, RecipeCost
+
+
+def _calorie_band(target: int, pct: int) -> tuple[int, int]:
+    delta = target * pct / 100.0
+    return (int(target - delta), int(target + delta))
+
+
+def filter_recipes(
+    *,
+    recipes: Iterable[dict],
+    recipe_ingredient_ids: Dict[UUID, Set[UUID]],
+    recipe_costs: Dict[UUID, RecipeCost],
+    blocked_ingredient_ids: Set[UUID],
+    blocked_recipe_ids: Set[UUID],
+    last_cooked_at: Dict[UUID, date],
+    family_calorie_target: Optional[int],
+    config: PlannerConfig,
+    today: date,
+) -> FilterResult:
+    feasible: List[UUID] = []
+    rejected: Dict[UUID, str] = {}
+
+    cal_band: Optional[tuple[int, int]] = None
+    if family_calorie_target is not None:
+        cal_band = _calorie_band(family_calorie_target, config.calorie_tolerance_pct)
+
+    recency_cutoff = today - timedelta(weeks=config.recency_weeks)
+
+    for r in recipes:
+        rid = r["id"]
+        if isinstance(rid, str):
+            rid = UUID(rid)
+
+        # #2: per-recipe blocklist
+        if rid in blocked_recipe_ids:
+            rejected[rid] = "blocked_recipe"
+            continue
+
+        # #1: ingredient blocklist intersection
+        if blocked_ingredient_ids & recipe_ingredient_ids.get(rid, set()):
+            rejected[rid] = "blocked_ingredient"
+            continue
+
+        # #3: recency
+        last = last_cooked_at.get(rid)
+        if last and last >= recency_cutoff:
+            rejected[rid] = "recency"
+            continue
+
+        # #4: calories
+        if cal_band is not None:
+            cps = r.get("calories_per_serving")
+            if cps is None:
+                rejected[rid] = "calories_missing"
+                continue
+            lo, hi = cal_band
+            if cps < lo or cps > hi:
+                rejected[rid] = "calories"
+                continue
+
+        # #5: time
+        prep = int(r.get("prep_time_minutes") or 0)
+        cook = int(r.get("cook_time_minutes") or 0)
+        if prep + cook > config.max_total_minutes:
+            rejected[rid] = "time"
+            continue
+
+        # #6: cost
+        cost = recipe_costs.get(rid)
+        if cost is None:
+            rejected[rid] = "no_cost"
+            continue
+        if float(cost.total_cost) > config.max_meal_cost:
+            rejected[rid] = "cost"
+            continue
+
+        feasible.append(rid)
+
+    return FilterResult(feasible_recipe_ids=feasible, rejected=rejected)