Epicure/apps/web/app/api/v1/ai/adapt/[id]/route.ts

import { NextRequest, NextResponse } from "next/server";
import { z } from "zod";
import { and, eq } from "@epicure/db";
import { db, recipes, recipeIngredients, recipeSteps } from "@epicure/db";
import { requireSession } from "@/lib/api-auth";
import { withAiQuota, resolveAiConfigOrError } from "@/lib/ai/ai-error";
import { adaptRecipe } from "@/lib/ai/features/adapt-recipe";
import { withUserKey } from "@/lib/ai/resolve-user-key";
import { getUserPrivateBio } from "@/lib/ai/user-bio";

const Schema = z.object({
  excludeIngredients: z.array(z.string()).default([]),
  extraConstraints: z.string().max(500).optional(),
  provider: z.enum(["openai", "anthropic", "openrouter", "ollama"]).optional(),
  model: z.string().optional(),
});

type Params = { params: Promise<{ id: string }> };

export async function POST(req: NextRequest, { params }: Params) {
  const { session, response } = await requireSession();
  if (response) return response;

  const { id } = await params;
  const userId = session!.user.id;

  const recipe = await db.query.recipes.findFirst({
    where: and(eq(recipes.id, id)),
    with: {
      ingredients: { orderBy: (t, { asc }) => asc(t.order) },
      steps: { orderBy: (t, { asc }) => asc(t.order) },
    },
  });
  if (!recipe || (recipe.visibility === "private" && recipe.authorId !== userId)) {
    return NextResponse.json({ error: "Not found" }, { status: 404 });
  }

  const body = await req.json() as unknown;
  const parsed = Schema.safeParse(body);
  if (!parsed.success) return NextResponse.json({ error: "Validation error" }, { status: 400 });

  if (parsed.data.excludeIngredients.length === 0 && !parsed.data.extraConstraints?.trim()) {
    return NextResponse.json({ error: "Provide at least one constraint" }, { status: 400 });
  }

  const [configResult, privateBio] = await Promise.all([
    resolveAiConfigOrError(() => withUserKey(userId, { provider: parsed.data.provider, model: parsed.data.model })),
    getUserPrivateBio(userId),
  ]);
  if (!configResult.ok) return configResult.response;
  const aiConfig = configResult.data;

  const result = await withAiQuota(userId, session!.user.tier as "free" | "pro", () =>
    adaptRecipe(
      {
        title: recipe.title,
        description: recipe.description,
        baseServings: recipe.baseServings,
        ingredients: recipe.ingredients,
        steps: recipe.steps,
      },
      {
        excludeIngredients: parsed.data.excludeIngredients,
        extraConstraints: parsed.data.extraConstraints,
      },
      { ...aiConfig, userContext: privateBio ?? undefined },
      (session!.user as { locale?: string }).locale ?? "en"
    )
  );
  if (!result.ok) return result.response;
  const adapted = result.data;

  const newId = crypto.randomUUID();
  const now = new Date();

  await db.transaction(async (tx) => {
    await tx.insert(recipes).values({
      id: newId,
      authorId: userId,
      title: adapted.title,
      description: adapted.description,
      baseServings: adapted.baseServings,
      visibility: "private",
      difficulty: adapted.difficulty,
      prepMins: adapted.prepMins,
      cookMins: adapted.cookMins,
      dietaryTags: adapted.dietaryTags ?? {},
      aiGenerated: true,
      createdAt: now,
      updatedAt: now,
    });

    if (adapted.ingredients.length > 0) {
      await tx.insert(recipeIngredients).values(
        adapted.ingredients.map((ing, i) => ({
          id: crypto.randomUUID(),
          recipeId: newId,
          rawName: ing.rawName,
          quantity: ing.quantity !== undefined ? String(ing.quantity) : undefined,
          unit: ing.unit,
          note: ing.note,
          order: i,
        }))
      );
    }

    if (adapted.steps.length > 0) {
      await tx.insert(recipeSteps).values(
        adapted.steps.map((step, i) => ({
          id: crypto.randomUUID(),
          recipeId: newId,
          instruction: step.instruction,
          timerSeconds: step.timerSeconds,
          order: i,
        }))
      );
    }
  });

  return NextResponse.json({ id: newId, adaptationNotes: adapted.adaptationNotes });
}