fix(3b): delad kompletteringsväg för legacy /cook + deterministiska cooking-assumptions

- cookRecipeInputSchema utökas med actualPortionsEaten, leftoverEstimatePortions, leftoverNote
- completeCookingSession-wrapper i apps/api/src/lib/cooking.ts hanterar summavalidering,
  persistens av svar, profiluppdateringar och analytics (started+completed) för båda vägarna
- Legacy POST /v1/recipes/:id/cook använder wrappern med emitStartedEvent
- GET /v1/recipes/:id/cooking-assumptions väljer deterministiskt bland icke-valfria ingredienser
- i18n: nyckel cooked.portionsSumExceedsPlanned i samtliga 12 lokaler + server-i18n
- Nya tester för legacy /cook och cooking-assumptions med valfri första ingrediens

Refs: steg 3b-fix, granskningsrunda 2026-08-07

apps/api/src/lib/cooking.ts

@@ -1,12 +1,15 @@
 import type { FastifyInstance } from "fastify";
 import { and, eq, gt, isNull, sql } from "drizzle-orm";
 import { schema, markMilestone } from "@app/database";
-import { allocateFefo } from "@app/inventory-engine";
+import { allocateFefo, updateCookingAssumptionProfile } from "@app/inventory-engine";
 import { scaleNutrition } from "@app/nutrition-engine";
 import type { Unit } from "@app/shared-types";
-import { todayIso, emitEvent } from "./helpers.js";
+import { cookingSessionStarted, cookingSessionCompleted } from "@app/analytics";
+import { todayIso, emitEvent, trackProductAnalytics } from "./helpers.js";
 import { errors } from "./errors.js";
 import { loadFullRecipe } from "../routes/recipes.js";
+import { userLanguageTag } from "./contentLanguage.js";
+import { t } from "./i18n.js";
 import { MEAL_TYPES } from "@app/shared-types";
 
 export interface CompleteCookingInput {
@@ -19,6 +22,14 @@ export interface CompleteCookingInput {
   date?: string;
   mealType?: string;
   inventoryOverrides?: Array<{ canonicalIngredientId: string; quantityUsed: number; unit: string }>;
+  actualPortionsEaten?: number;
+  leftoverEstimatePortions?: number;
+  leftoverNote?: string;
+}
+
+export interface CompleteCookingSessionOptions {
+  /** Sant för legacy POST /v1/recipes/:id/cook där session skapas och startas i ett steg. */
+  emitStartedEvent?: boolean;
 }
 
 export interface CompleteCookingResult {
@@ -30,8 +41,138 @@ export interface CompleteCookingResult {
 }
 
 /**
- * Gemensam kärna för att "jag har lagat". Används av både
- * POST /v1/recipes/:id/cook (legacy shortcut) och
+ * Delad kompletteringsväg för både POST /v1/recipes/:id/cook (legacy)
+ * och POST /v1/cooking-sessions/:id/complete. Hanterar summavalidering,
+ * persistens av svar, profiluppdateringar och analytics.
+ */
+export async function completeCookingSession(
+  app: FastifyInstance,
+  session: typeof schema.cookingSessions.$inferSelect,
+  userId: string,
+  input: CompleteCookingInput,
+  correlationId: string,
+  options: CompleteCookingSessionOptions = {},
+): Promise<CompleteCookingResult & { session: typeof schema.cookingSessions.$inferSelect }> {
+  const plannedPortions = input.portionsCooked ?? session.plannedPortions;
+  const mealBoxPortions = input.mealBoxPortions ?? 0;
+  const actualPortionsEaten = input.actualPortionsEaten ?? Math.max(0, plannedPortions - mealBoxPortions);
+  const leftoverEstimatePortions = input.leftoverEstimatePortions ?? mealBoxPortions;
+
+  if (actualPortionsEaten + leftoverEstimatePortions > plannedPortions) {
+    const languageTag = await userLanguageTag(app.db, userId);
+    throw errors.badRequest(t("cooked.portionsSumExceedsPlanned", languageTag));
+  }
+
+  if (options.emitStartedEvent && session.status === "started") {
+    await trackProductAnalytics(
+      app.db,
+      userId,
+      cookingSessionStarted({
+        householdId: session.householdId,
+        properties: {
+          cookingSessionId: session.id,
+          recipeId: session.recipeId,
+          status: session.status,
+          plannedPortions,
+        },
+      }),
+    );
+  }
+
+  const result = await completeCookingSessionCore(
+    app,
+    session,
+    userId,
+    { ...input, portionsCooked: plannedPortions, mealBoxPortions },
+    correlationId,
+  );
+
+  // Persistera användarens svar (ersätter kärnans default-värden).
+  const [updated] = await app.db
+    .update(schema.cookingSessions)
+    .set({
+      actualPortionsEaten,
+      leftoverEstimatePortions,
+      leftoverNote: input.leftoverNote ?? null,
+      updatedAt: new Date(),
+    })
+    .where(eq(schema.cookingSessions.id, session.id))
+    .returning();
+  if (!updated) throw errors.internal("Kunde inte uppdatera cooking session.");
+
+  // Uppdatera antagandeprofiler per icke-valfri ingrediens (hushållsnivå).
+  const date = new Date().toISOString().slice(0, 10);
+  for (const ing of result.recipeIngredients) {
+    if (ing.optional) continue;
+    const [existing] = await app.db
+      .select()
+      .from(schema.cookingAssumptionProfiles)
+      .where(
+        and(
+          eq(schema.cookingAssumptionProfiles.householdId, session.householdId),
+          eq(schema.cookingAssumptionProfiles.canonicalIngredientId, ing.canonicalIngredientId),
+        ),
+      )
+      .limit(1);
+
+    const updatedProfile = updateCookingAssumptionProfile(
+      {
+        householdId: session.householdId,
+        canonicalIngredientId: ing.canonicalIngredientId,
+        plannedPortions,
+        actualPortionsEaten,
+        leftoverEstimatePortions,
+        sessionId: session.id,
+        date,
+      },
+      existing ?? { averageEatenPortions: null, averageLeftoverPortions: null, observationCount: 0 },
+    );
+
+    await app.db
+      .insert(schema.cookingAssumptionProfiles)
+      .values({
+        householdId: session.householdId,
+        canonicalIngredientId: ing.canonicalIngredientId,
+        ...updatedProfile,
+        updatedAt: new Date(),
+      })
+      .onConflictDoUpdate({
+        target: [
+          schema.cookingAssumptionProfiles.householdId,
+          schema.cookingAssumptionProfiles.canonicalIngredientId,
+        ],
+        set: {
+          averageEatenPortions: updatedProfile.averageEatenPortions,
+          averageLeftoverPortions: updatedProfile.averageLeftoverPortions,
+          observationCount: updatedProfile.observationCount,
+          lastSessionAnswers: updatedProfile.lastSessionAnswers,
+          updatedAt: new Date(),
+        },
+      });
+  }
+
+  await trackProductAnalytics(
+    app.db,
+    userId,
+    cookingSessionCompleted({
+      householdId: session.householdId,
+      properties: {
+        cookingSessionId: session.id,
+        recipeId: session.recipeId,
+        portionsCooked: plannedPortions,
+        actualPortionsEaten,
+        leftoverEstimatePortions,
+        mealBoxPortions,
+      },
+    }),
+  );
+
+  return { ...result, session: updated };
+}
+
+/**
+ * Lågnivå-kärna för att "jag har lagat". Används via completeCookingSession
+ * av både POST /v1/recipes/:id/cook (legacy shortcut) och
  * POST /v1/cooking-sessions/:id/complete.
  */
 export async function completeCookingSessionCore(
@@ -234,14 +375,12 @@ export async function completeCookingSessionCore(
     correlationId,
   });
 
-  // 5. Uppdatera session
+  // 5. Uppdatera session (svaren skrivs över av completeCookingSession).
   await app.db
     .update(schema.cookingSessions)
     .set({
       status: "completed",
       completedAt: new Date(),
-      actualPortionsEaten: portionsCooked - mealBoxPortions,
-      leftoverEstimatePortions: mealBoxPortions,
       plannedDeductions: deductions,
       updatedAt: new Date(),
     })

apps/api/src/lib/i18n.ts

@@ -19,14 +19,35 @@ const HOUSEHOLD_DEFAULT_NAMES: Record<string, string> = {
   sv: "Hemma",
 };
 
+const COOKED_PORTIONS_SUM_EXCEEDS_PLANNED: Record<string, string> = {
+  da: "Antal spiste portioner og rester må ikke overstige det samlede antal portioner.",
+  de: "Gegessene Portionen und Reste dürfen die Gesamtanzahl der Portionen nicht überschreiten.",
+  en: "Eaten portions and leftovers cannot exceed the total number of portions.",
+  es: "Las raciones comidas y las sobras no pueden superar el número total de raciones.",
+  fi: "Syödyt annokset ja tähteet eivät voi ylittää annosten kokonaismäärää.",
+  fr: "Les portions mangées et les restes ne peuvent pas dépasser le nombre total de portions.",
+  it: "Le porzioni mangiate e gli avanzi non possono superare il numero totale di porzioni.",
+  nb: "Antall spiste porsjoner og rester kan ikke overstige det totale antallet porsjoner.",
+  nl: "Gegeten porties en restjes mogen het totaal aantal porties niet overschrijden.",
+  pl: "Zjedzone porcje i resztki nie mogą przekroczyć całkowitej liczby porcji.",
+  pt: "As porções comidas e as sobras não podem ultrapassar o número total de porções.",
+  sv: "Antalet ätna portioner och rester får inte överstiga det totala antalet portioner.",
+};
+
+function resolve(catalog: Record<string, string>, languageTag: string): string {
+  const lang = (languageTag.split("-")[0] ?? "sv").toLowerCase();
+  return catalog[lang] ?? catalog["en"] ?? catalog["sv"]!;
+}
+
 export function t(key: string, languageTag: string): string {
+  if (key === "cooked.portionsSumExceedsPlanned") {
+    return resolve(COOKED_PORTIONS_SUM_EXCEEDS_PLANNED, languageTag);
+  }
+
   if (key !== "onboarding.householdDefaultName") {
     // No other server-side keys are supported yet; fall back to a safe default.
     return HOUSEHOLD_DEFAULT_NAMES["sv"]!;
   }
 
-  const lang = (languageTag.split("-")[0] ?? "sv").toLowerCase();
-  return (
-    HOUSEHOLD_DEFAULT_NAMES[lang] ?? HOUSEHOLD_DEFAULT_NAMES["en"] ?? HOUSEHOLD_DEFAULT_NAMES["sv"]!
-  );
+  return resolve(HOUSEHOLD_DEFAULT_NAMES, languageTag);
 }

apps/api/src/routes/cooking-sessions.ts

@@ -1,5 +1,5 @@
 import type { FastifyInstance } from "fastify";
-import { and, eq, lt } from "drizzle-orm";
+import { and, eq, inArray, lt } from "drizzle-orm";
 import { schema, markMilestone } from "@app/database";
 import {
   cookingSessionStartInputSchema,
@@ -8,14 +8,9 @@ import {
 } from "@app/validation";
 import { errors, parse } from "../lib/errors.js";
 import { requireActiveHousehold, requireMembership } from "../lib/helpers.js";
-import {
-  cookingSessionStarted,
-  cookingSessionCompleted,
-  cookingSessionCancelled,
-} from "@app/analytics";
+import { cookingSessionStarted, cookingSessionCancelled } from "@app/analytics";
 import { trackProductAnalytics } from "../lib/helpers.js";
-import { completeCookingSessionCore } from "../lib/cooking.js";
-import { updateCookingAssumptionProfile } from "@app/inventory-engine";
+import { completeCookingSession } from "../lib/cooking.js";
 import { z } from "zod";
 
 /**
@@ -137,8 +132,8 @@ export async function cookingSessionRoutes(app: FastifyInstance) {
 
   /**
    * Complete en session.
-   * I steg 3a: anropar samma logik som gamla /cook, men länkar allt till cookingSessionId.
-   * I steg 3b: sparar svar på max 2–3 frågor och uppdaterar hushållsantagandeprofiler.
+   * Delad kompletteringsväg via completeCookingSession hanterar summavalidering,
+   * persistens, profiluppdateringar och analytics.
    */
   app.post("/v1/cooking-sessions/:id/complete", auth, async (req) => {
     const { id } = parse(idParamSchema, req.params);
@@ -148,107 +143,9 @@ export async function cookingSessionRoutes(app: FastifyInstance) {
       throw errors.conflict("Sessionen måste vara startad för att avslutas.");
     }
 
-    const mealBoxPortions = input.mealBoxPortions ?? 0;
-    const plannedPortions = input.portionsCooked ?? session.plannedPortions;
-    const actualPortionsEaten = input.actualPortionsEaten ?? Math.max(0, plannedPortions - mealBoxPortions);
-    const leftoverEstimatePortions = input.leftoverEstimatePortions ?? mealBoxPortions;
+    const result = await completeCookingSession(app, session, req.userId, input, req.correlationId);
 
-    if (actualPortionsEaten + leftoverEstimatePortions > plannedPortions) {
-      throw errors.badRequest("Åtna portioner + rester får inte överstiga totalt antal portioner.");
-    }
-
-    const result = await completeCookingSessionCore(
-      app,
-      session,
-      req.userId,
-      { ...input, portionsCooked: plannedPortions, mealBoxPortions },
-      req.correlationId,
-    );
-
-    await app.db
-      .update(schema.cookingSessions)
-      .set({
-        actualPortionsEaten,
-        leftoverEstimatePortions,
-        leftoverNote: input.leftoverNote ?? null,
-        updatedAt: new Date(),
-      })
-      .where(eq(schema.cookingSessions.id, id));
-
-    // Uppdatera antagandeprofiler per ingrediens (hushållsnivå).
-    const date = new Date().toISOString().slice(0, 10);
-    for (const ing of result.recipeIngredients) {
-      if (ing.optional) continue;
-      const [existing] = await app.db
-        .select()
-        .from(schema.cookingAssumptionProfiles)
-        .where(
-          and(
-            eq(schema.cookingAssumptionProfiles.householdId, session.householdId),
-            eq(schema.cookingAssumptionProfiles.canonicalIngredientId, ing.canonicalIngredientId),
-          ),
-        )
-        .limit(1);
-
-      const updatedProfile = updateCookingAssumptionProfile(
-        {
-          householdId: session.householdId,
-          canonicalIngredientId: ing.canonicalIngredientId,
-          plannedPortions,
-          actualPortionsEaten,
-          leftoverEstimatePortions,
-          sessionId: id,
-          date,
-        },
-        existing ?? { averageEatenPortions: null, averageLeftoverPortions: null, observationCount: 0 },
-      );
-
-      await app.db
-        .insert(schema.cookingAssumptionProfiles)
-        .values({
-          householdId: session.householdId,
-          canonicalIngredientId: ing.canonicalIngredientId,
-          ...updatedProfile,
-          updatedAt: new Date(),
-        })
-        .onConflictDoUpdate({
-          target: [
-            schema.cookingAssumptionProfiles.householdId,
-            schema.cookingAssumptionProfiles.canonicalIngredientId,
-          ],
-          set: {
-            averageEatenPortions: updatedProfile.averageEatenPortions,
-            averageLeftoverPortions: updatedProfile.averageLeftoverPortions,
-            observationCount: updatedProfile.observationCount,
-            lastSessionAnswers: updatedProfile.lastSessionAnswers,
-            updatedAt: new Date(),
-          },
-        });
-    }
-
-    const [updated] = await app.db
-      .select()
-      .from(schema.cookingSessions)
-      .where(eq(schema.cookingSessions.id, id))
-      .limit(1);
-
-    await trackProductAnalytics(
-      app.db,
-      req.userId,
-      cookingSessionCompleted({
-        householdId: session.householdId,
-        properties: {
-          cookingSessionId: id,
-          recipeId: session.recipeId,
-          portionsCooked: plannedPortions,
-          actualPortionsEaten,
-          leftoverEstimatePortions,
-          mealBoxPortions,
-        },
-      }),
-    );
-
-    return { ...result, session: updated };
+    return result;
   });
 
   /** Hämta antagandeprofil för ett recept (per hushåll + ingrediens). */
@@ -258,23 +155,38 @@ export async function cookingSessionRoutes(app: FastifyInstance) {
     await requireMembership(app.db, householdId, req.userId);
 
     const ings = await app.db
-      .select({ canonicalIngredientId: schema.recipeIngredients.canonicalIngredientId })
+      .select({
+        canonicalIngredientId: schema.recipeIngredients.canonicalIngredientId,
+        optional: schema.recipeIngredients.optional,
+      })
       .from(schema.recipeIngredients)
       .where(eq(schema.recipeIngredients.recipeId, id));
     if (ings.length === 0) throw errors.notFound("Receptet finns inte.");
 
+    const nonOptionalIds = ings.filter((i) => !i.optional).map((i) => i.canonicalIngredientId);
+    if (nonOptionalIds.length === 0) {
+      return {
+        householdId,
+        recipeId: id,
+        defaultActualPortionsEaten: null,
+        defaultLeftoverEstimatePortions: null,
+        observationCount: 0,
+      };
+    }
+
     const profiles = await app.db
       .select()
       .from(schema.cookingAssumptionProfiles)
       .where(
         and(
           eq(schema.cookingAssumptionProfiles.householdId, householdId),
-          eq(schema.cookingAssumptionProfiles.canonicalIngredientId, ings[0]!.canonicalIngredientId),
+          inArray(schema.cookingAssumptionProfiles.canonicalIngredientId, nonOptionalIds),
         ),
-      )
-      .limit(1);
+      );
+
+    // Deterministiskt val: profilen med flest observationer (stabil över tid).
+    const p = profiles.sort((a, b) => b.observationCount - a.observationCount)[0];
 
-    const p = profiles[0];
     return {
       householdId,
       recipeId: id,

apps/api/src/routes/recipes.ts

@@ -32,7 +32,7 @@ import {
   todayIso,
 } from "../lib/helpers.js";
 import { requireFeature } from "../lib/entitlements.js";
-import { completeCookingSessionCore } from "../lib/cooking.js";
+import { completeCookingSession } from "../lib/cooking.js";
 
 /** Recept: sök, detalj, betyg, favoriter, "jag har lagat", substitutioner, användarrecept. */
 export async function recipeRoutes(app: FastifyInstance) {
@@ -433,7 +433,9 @@ export async function recipeRoutes(app: FastifyInstance) {
       })
       .returning();
 
-    const result = await completeCookingSessionCore(app, session!, req.userId, input, req.correlationId);
+    const result = await completeCookingSession(app, session!, req.userId, input, req.correlationId, {
+      emitStartedEvent: true,
+    });
 
     return { sessionId: session!.id, ...result };
   });

apps/api/test/cooking-sessions.test.ts

@@ -1,6 +1,6 @@
 import "./setup-env.js";
 import { describe, expect, it, beforeAll, afterAll } from "vitest";
-import { and, eq, inArray, count } from "drizzle-orm";
+import { and, eq, inArray, count, sql } from "drizzle-orm";
 import { buildServer } from "../src/server.js";
 import { loadConfig } from "../src/config.js";
 import { createDatabase, closeDatabase, schema } from "@app/database";
@@ -235,6 +235,115 @@ describe("cooking sessions", () => {
     expect(body.mealBoxId).toBeDefined();
   });
 
+  it("legacy /cook stores actual portions and leftover estimate on the session row", async () => {
+    const res = await app.inject({
+      method: "POST",
+      url: `/v1/recipes/${recipeId}/cook`,
+      headers: { authorization: `Bearer ${token}` },
+      payload: {
+        portionsCooked: 4,
+        mealBoxPortions: 1,
+        actualPortionsEaten: 2,
+        leftoverEstimatePortions: 1,
+        leftoverNote: "sparas i kylen",
+        deductInventory: true,
+      },
+    });
+    expect(res.statusCode).toBe(200);
+    const { sessionId } = JSON.parse(res.body) as { sessionId: string };
+
+    const session = await testDb.db
+      .select()
+      .from(schema.cookingSessions)
+      .where(eq(schema.cookingSessions.id, sessionId))
+      .limit(1);
+    expect(session[0]!.actualPortionsEaten).toBe(2);
+    expect(session[0]!.leftoverEstimatePortions).toBe(1);
+    expect(session[0]!.leftoverNote).toBe("sparas i kylen");
+  });
+
+  it("legacy /cook updates cooking assumption profiles", async () => {
+    await testDb.db.delete(schema.cookingAssumptionProfiles).where(eq(schema.cookingAssumptionProfiles.householdId, householdId));
+
+    const recipe = (await app.inject({
+      method: "GET",
+      url: `/v1/recipes/${recipeId}`,
+      headers: { authorization: `Bearer ${token}` },
+    })).json() as { ingredients: Array<{ canonicalIngredientId: string; optional?: boolean }> };
+    const firstNonOptionalIngredientId = recipe.ingredients.find((i) => i.canonicalIngredientId && !i.optional)?.canonicalIngredientId;
+    expect(firstNonOptionalIngredientId).toBeDefined();
+
+    await app.inject({
+      method: "POST",
+      url: `/v1/recipes/${recipeId}/cook`,
+      headers: { authorization: `Bearer ${token}` },
+      payload: {
+        portionsCooked: 4,
+        actualPortionsEaten: 3,
+        leftoverEstimatePortions: 1,
+        deductInventory: true,
+      },
+    });
+
+    const profile = await testDb.db
+      .select()
+      .from(schema.cookingAssumptionProfiles)
+      .where(
+        and(
+          eq(schema.cookingAssumptionProfiles.householdId, householdId),
+          eq(schema.cookingAssumptionProfiles.canonicalIngredientId, firstNonOptionalIngredientId!),
+        ),
+      )
+      .limit(1);
+    expect(profile.length).toBe(1);
+    expect(profile[0]!.observationCount).toBe(1);
+    expect(profile[0]!.averageEatenPortions).toBe(3);
+    expect(profile[0]!.averageLeftoverPortions).toBe(1);
+  });
+
+  it("legacy /cook writes cooking_session_started and cooking_session_completed analytics", async () => {
+    const before = await testDb.db
+      .select({ name: schema.productAnalyticsEvents.eventName })
+      .from(schema.productAnalyticsEvents)
+      .where(eq(schema.productAnalyticsEvents.userId, userId));
+
+    const res = await app.inject({
+      method: "POST",
+      url: `/v1/recipes/${recipeId}/cook`,
+      headers: { authorization: `Bearer ${token}` },
+      payload: { portionsCooked: 4, deductInventory: true },
+    });
+    expect(res.statusCode).toBe(200);
+    const { sessionId } = JSON.parse(res.body) as { sessionId: string };
+
+    const after = await testDb.db
+      .select()
+      .from(schema.productAnalyticsEvents)
+      .where(eq(schema.productAnalyticsEvents.userId, userId))
+      .orderBy(schema.productAnalyticsEvents.occurredAt);
+    const newEvents = after.slice(before.length);
+    const props = (e: (typeof after)[number]) => (e.properties ?? {}) as { cookingSessionId?: string };
+    const started = newEvents.filter((e) => e.eventName === "cooking_session_started" && props(e).cookingSessionId === sessionId);
+    const completed = newEvents.filter((e) => e.eventName === "cooking_session_completed" && props(e).cookingSessionId === sessionId);
+    expect(started.length).toBe(1);
+    expect(completed.length).toBe(1);
+  });
+
+  it("legacy /cook rejects when eaten + leftovers exceed planned portions", async () => {
+    const res = await app.inject({
+      method: "POST",
+      url: `/v1/recipes/${recipeId}/cook`,
+      headers: { authorization: `Bearer ${token}` },
+      payload: {
+        portionsCooked: 4,
+        mealBoxPortions: 0,
+        actualPortionsEaten: 3,
+        leftoverEstimatePortions: 2,
+      },
+    });
+    expect(res.statusCode).toBe(400);
+  });
+
   it("stores actual portions and leftover estimate on complete", async () => {
     const start = await app.inject({
       method: "POST",
@@ -289,8 +398,9 @@ describe("cooking sessions", () => {
       method: "GET",
       url: `/v1/recipes/${recipeId}`,
       headers: { authorization: `Bearer ${token}` },
-    })).json() as { ingredients: Array<{ canonicalIngredientId: string }> };
-    const firstIngredientId = recipe.ingredients.find((i) => i.canonicalIngredientId)?.canonicalIngredientId;
+    })).json() as { ingredients: Array<{ canonicalIngredientId: string; optional?: boolean }> };
+    const firstNonOptionalIngredientId = recipe.ingredients.find((i) => i.canonicalIngredientId && !i.optional)?.canonicalIngredientId;
+    expect(firstNonOptionalIngredientId).toBeDefined();
 
     await app.inject({
       method: "POST",
@@ -299,14 +409,13 @@ describe("cooking sessions", () => {
       payload: { mealBoxPortions: 1, actualPortionsEaten: 2, leftoverEstimatePortions: 1 },
     });
 
-    if (firstIngredientId) {
     const profile = await testDb.db
       .select()
       .from(schema.cookingAssumptionProfiles)
       .where(
         and(
           eq(schema.cookingAssumptionProfiles.householdId, householdId),
-            eq(schema.cookingAssumptionProfiles.canonicalIngredientId, firstIngredientId),
+          eq(schema.cookingAssumptionProfiles.canonicalIngredientId, firstNonOptionalIngredientId!),
         ),
       )
       .limit(1);
@@ -314,7 +423,104 @@ describe("cooking sessions", () => {
     expect(profile[0]!.observationCount).toBe(1);
     expect(profile[0]!.averageEatenPortions).toBe(2);
     expect(profile[0]!.averageLeftoverPortions).toBe(1);
-    }
+  });
+
+  it("cooking-assumptions ignores optional first ingredient and returns defaults from a non-optional one", async () => {
+    await testDb.db.delete(schema.cookingAssumptionProfiles).where(eq(schema.cookingAssumptionProfiles.householdId, householdId));
+
+    // Skapa ett recept där den första ingrediensen är valfri.
+    const [recipe] = await testDb.db
+      .insert(schema.recipes)
+      .values({
+        slug: `optional-first-${Date.now()}`,
+        titleSv: "Testrecept valfri först",
+        descriptionSv: "",
+        cuisine: "international",
+        mealTypes: ["dinner"],
+        tags: [],
+        methods: [],
+        equipment: [],
+        difficulty: "easy",
+        prepTimeMinutes: 5,
+        cookTimeMinutes: 10,
+        totalTimeMinutes: 15,
+        portions: 4,
+        nutritionPerPortion: { kcal: 100, proteinG: 5, fatG: 3, carbsG: 12, saturatedFatG: 1, fiberG: 1, sugarG: 2, saltG: 0.1 },
+        allergens: [],
+        spiceLevel: 0,
+        dna: {
+          cuisine: "international",
+          vegetables: [],
+          flavorProfile: [],
+          spiceLevel: 0,
+          method: "stovetop",
+          timeMinutes: 15,
+          calories: 100,
+          proteinGrams: 5,
+        },
+        status: "published",
+        verificationStatus: "unverified",
+        sourceType: "own_editorial",
+        creatorDisplayName: "Test",
+      })
+      .returning();
+    const testRecipeId = recipe!.id;
+
+    await testDb.db.insert(schema.recipeIngredients).values([
+      {
+        recipeId: testRecipeId,
+        canonicalIngredientId: "olive_oil",
+        displayNameSv: "Olivolja",
+        quantity: 1,
+        unit: "TABLESPOON",
+        optional: true,
+        sortOrder: 0,
+      },
+      {
+        recipeId: testRecipeId,
+        canonicalIngredientId: "pasta_dry",
+        displayNameSv: "Pasta",
+        quantity: 320,
+        unit: "GRAM",
+        optional: false,
+        sortOrder: 1,
+      },
+    ]);
+
+    // Completa en session och skriv profil för den icke-valfria ingrediensen.
+    const start = await app.inject({
+      method: "POST",
+      url: `/v1/recipes/${testRecipeId}/cook/start`,
+      headers: { authorization: `Bearer ${token}` },
+      payload: { startNow: true, portions: 4 },
+    });
+    const sessionId = (JSON.parse(start.body) as { session: { id: string } }).session.id;
+
+    await app.inject({
+      method: "POST",
+      url: `/v1/cooking-sessions/${sessionId}/complete`,
+      headers: { authorization: `Bearer ${token}` },
+      payload: { mealBoxPortions: 0, actualPortionsEaten: 3, leftoverEstimatePortions: 1 },
+    });
+
+    const assumptions = await app.inject({
+      method: "GET",
+      url: `/v1/recipes/${testRecipeId}/cooking-assumptions`,
+      headers: { authorization: `Bearer ${token}` },
+    });
+    expect(assumptions.statusCode).toBe(200);
+    const body = JSON.parse(assumptions.body) as {
+      defaultActualPortionsEaten: number | null;
+      defaultLeftoverEstimatePortions: number | null;
+      observationCount: number;
+    };
+    expect(body.observationCount).toBe(1);
+    expect(body.defaultActualPortionsEaten).toBe(3);
+    expect(body.defaultLeftoverEstimatePortions).toBe(1);
+
+    // Städa upp testreceptet.
+    await testDb.db.delete(schema.recipeIngredients).where(eq(schema.recipeIngredients.recipeId, testRecipeId));
+    await testDb.db.delete(schema.recipes).where(eq(schema.recipes.id, testRecipeId));
   });
 
   it("emits cooking_session_completed on complete and cooking_session_cancelled on cancel", async () => {

apps/mobile/src/locales/da/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Bekræft alle",
   "scan.diff.noChanges": "Ingen forskelle fundet.",
   "scan.diff.undo": "Fortryd",
-  "scan.diff.undoHint": "Hver ændring kan fortrydes fra varedetaljevisningen."
+  "scan.diff.undoHint": "Hver ændring kan fortrydes fra varedetaljevisningen.",
+  "cooked.portionsSumExceedsPlanned": "Antal spiste portioner og rester må ikke overstige det samlede antal portioner."
 }

apps/mobile/src/locales/de/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Alle bestätigen",
   "scan.diff.noChanges": "Keine Unterschiede gefunden.",
   "scan.diff.undo": "Rückgängig",
-  "scan.diff.undoHint": "Jede Änderung kann in der Artikeldetailansicht rückgängig gemacht werden."
+  "scan.diff.undoHint": "Jede Änderung kann in der Artikeldetailansicht rückgängig gemacht werden.",
+  "cooked.portionsSumExceedsPlanned": "Gegessene Portionen und Reste dürfen die Gesamtanzahl der Portionen nicht überschreiten."
 }

apps/mobile/src/locales/en/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Confirm all",
   "scan.diff.noChanges": "No differences found.",
   "scan.diff.undo": "Undo",
-  "scan.diff.undoHint": "Each change can be undone from the item detail view."
+  "scan.diff.undoHint": "Each change can be undone from the item detail view.",
+  "cooked.portionsSumExceedsPlanned": "Eaten portions and leftovers cannot exceed the total number of portions."
 }

apps/mobile/src/locales/es/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Confirmar todo",
   "scan.diff.noChanges": "No se encontraron diferencias.",
   "scan.diff.undo": "Deshacer",
-  "scan.diff.undoHint": "Cada cambio se puede deshacer desde la vista de detalle del producto."
+  "scan.diff.undoHint": "Cada cambio se puede deshacer desde la vista de detalle del producto.",
+  "cooked.portionsSumExceedsPlanned": "Las raciones comidas y las sobras no pueden superar el número total de raciones."
 }

apps/mobile/src/locales/fi/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Vahvista kaikki",
   "scan.diff.noChanges": "Eroja ei löytynyt.",
   "scan.diff.undo": "Kumoa",
-  "scan.diff.undoHint": "Jokainen muutos voidaan kumota tuotteen tietonäkymästä."
+  "scan.diff.undoHint": "Jokainen muutos voidaan kumota tuotteen tietonäkymästä.",
+  "cooked.portionsSumExceedsPlanned": "Syödyt annokset ja tähteet eivät voi ylittää annosten kokonaismäärää."
 }

apps/mobile/src/locales/fr/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Tout confirmer",
   "scan.diff.noChanges": "Aucune différence trouvée.",
   "scan.diff.undo": "Annuler",
-  "scan.diff.undoHint": "Chaque modification peut être annulée depuis la vue détail de l'article."
+  "scan.diff.undoHint": "Chaque modification peut être annulée depuis la vue détail de l'article.",
+  "cooked.portionsSumExceedsPlanned": "Les portions mangées et les restes ne peuvent pas dépasser le nombre total de portions."
 }

apps/mobile/src/locales/it/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Conferma tutto",
   "scan.diff.noChanges": "Nessuna differenza trovata.",
   "scan.diff.undo": "Annulla",
-  "scan.diff.undoHint": "Ogni modifica può essere annullata dalla vista dettaglio dell'articolo."
+  "scan.diff.undoHint": "Ogni modifica può essere annullata dalla vista dettaglio dell'articolo.",
+  "cooked.portionsSumExceedsPlanned": "Le porzioni mangiate e gli avanzi non possono superare il numero totale di porzioni."
 }

apps/mobile/src/locales/nb/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Bekreft alle",
   "scan.diff.noChanges": "Ingen forskjeller funnet.",
   "scan.diff.undo": "Angre",
-  "scan.diff.undoHint": "Hver endring kan angres fra varedetaljvisningen."
+  "scan.diff.undoHint": "Hver endring kan angres fra varedetaljvisningen.",
+  "cooked.portionsSumExceedsPlanned": "Antall spiste porsjoner og rester kan ikke overstige det totale antallet porsjoner."
 }

apps/mobile/src/locales/nl/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Alles bevestigen",
   "scan.diff.noChanges": "Geen verschillen gevonden.",
   "scan.diff.undo": "Ongedaan maken",
-  "scan.diff.undoHint": "Elke wijziging kan ongedaan worden gemaakt vanuit de detailweergave."
+  "scan.diff.undoHint": "Elke wijziging kan ongedaan worden gemaakt vanuit de detailweergave.",
+  "cooked.portionsSumExceedsPlanned": "Gegeten porties en restjes mogen het totaal aantal porties niet overschrijden."
 }

apps/mobile/src/locales/pl/common.json

@@ -396,5 +396,6 @@
   "scan.diff.acceptAll": "Potwierdź wszystko",
   "scan.diff.noChanges": "Nie znaleziono różnic.",
   "scan.diff.undo": "Cofnij",
-  "scan.diff.undoHint": "Każdą zmianę można cofnąć z widoku szczegółów produktu."
+  "scan.diff.undoHint": "Każdą zmianę można cofnąć z widoku szczegółów produktu.",
+  "cooked.portionsSumExceedsPlanned": "Zjedzone porcje i resztki nie mogą przekroczyć całkowitej liczby porcji."
 }

apps/mobile/src/locales/pt/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Confirmar tudo",
   "scan.diff.noChanges": "Nenhuma diferença encontrada.",
   "scan.diff.undo": "Desfazer",
-  "scan.diff.undoHint": "Cada alteração pode ser desfeita a partir da vista de detalhes do item."
+  "scan.diff.undoHint": "Cada alteração pode ser desfeita a partir da vista de detalhes do item.",
+  "cooked.portionsSumExceedsPlanned": "As porções comidas e as sobras não podem ultrapassar o número total de porções."
 }

apps/mobile/src/locales/sv/common.json

@@ -382,5 +382,6 @@
   "scan.diff.acceptAll": "Bekräfta alla",
   "scan.diff.noChanges": "Inga skillnader hittades.",
   "scan.diff.undo": "Ångra",
-  "scan.diff.undoHint": "Varje ändring kan ångras från varans detaljvy."
+  "scan.diff.undoHint": "Varje ändring kan ångras från varans detaljvy.",
+  "cooked.portionsSumExceedsPlanned": "Antalet ätna portioner och rester får inte överstiga det totala antalet portioner."
 }

packages/validation/src/recipes.ts

@@ -122,6 +122,12 @@ export const cookRecipeInputSchema = z.object({
     .regex(/^\d{4}-\d{2}-\d{2}$/)
     .optional(),
   mealType: z.enum(MEAL_TYPES).default("dinner"),
+  /** Antal portioner som faktiskt åts (steg 3c). */
+  actualPortionsEaten: z.number().int().min(0).max(24).optional(),
+  /** Uppskattade restportioner efter måltiden (steg 3c). */
+  leftoverEstimatePortions: z.number().int().min(0).max(24).optional(),
+  /** Fritextnotering om rester – aldrig i analytics. */
+  leftoverNote: z.string().max(200).optional(),
 });
 export type CookRecipeInput = z.infer<typeof cookRecipeInputSchema>;
 
@@ -152,8 +158,5 @@ export const cookingSessionCompleteInputSchema = cookRecipeInputSchema.partial()
     )
     .default([]),
   mealType: z.enum(MEAL_TYPES).optional(),
-  actualPortionsEaten: z.number().int().min(0).max(24).optional(),
-  leftoverEstimatePortions: z.number().int().min(0).max(24).optional(),
-  leftoverNote: z.string().max(200).optional(),
 });
 export type CookingSessionCompleteInput = z.infer<typeof cookingSessionCompleteInputSchema>;