import { NextRequest, NextResponse } from "next/server";
import { db, recipes, recipeIngredients, recipeSteps, recipePhotos, recipeBatchDishes } from "@epicure/db";
import { eq, desc, and } from "@epicure/db";
import { z } from "zod";
import { requireSessionOrApiKey } from "@/lib/api-auth";
import { isOwnedRecipePhotoKey } from "@/lib/storage";
import { checkTierLimitInTransaction, TierLimitError } from "@/lib/tiers";
import { dispatchWebhook } from "@/lib/webhooks";
import { parseQuantity } from "@/lib/parse-quantity";
import { extractIngredientQuantity } from "@/lib/extract-ingredient-quantity";

const CreateRecipeSchema = z.object({
  title: z.string().min(1).max(200),
  description: z.string().max(2000).optional(),
  baseServings: z.number().int().min(1).max(100).default(4),
  recipeType: z.enum(["dish", "drink"]).default("dish"),
  visibility: z.enum(["private", "unlisted", "public", "followers"]).default("private"),
  difficulty: z.enum(["easy", "medium", "hard"]).optional(),
  prepMins: z.number().int().min(0).max(1440).optional(),
  cookMins: z.number().int().min(0).max(1440).optional(),
  tags: z.array(z.string().min(1).max(50)).max(20).default([]),
  aiGenerated: z.boolean().optional(),
  language: z.string().max(10).optional(),
  sourceUrl: z.string().url().max(2000).optional(),
  dietaryTags: z.object({
    vegan: z.boolean().optional(),
    vegetarian: z.boolean().optional(),
    glutenFree: z.boolean().optional(),
    dairyFree: z.boolean().optional(),
    nutFree: z.boolean().optional(),
    halal: z.boolean().optional(),
    kosher: z.boolean().optional(),
  }).optional(),
  ingredients: z.array(z.object({
    rawName: z.string().min(1).max(200),
    quantity: z.union([z.number(), z.string()]).optional().transform(parseQuantity),
    unit: z.string().max(50).optional(),
    note: z.string().max(500).optional(),
    order: z.number().int().default(0),
  }).transform((ing) => {
    const { rawName, quantity, unit } = extractIngredientQuantity(ing.rawName, ing.quantity, ing.unit);
    return { ...ing, rawName, quantity, unit };
  })).max(100).default([]),
  steps: z.array(z.object({
    instruction: z.string().min(1).max(2000),
    timerSeconds: z.number().int().min(0).max(86400).optional(),
    order: z.number().int().optional(),
    appliesTo: z.array(z.string().min(1).max(100)).max(20).default([]),
  })).max(100).default([]),
  photos: z.array(z.object({
    key: z.string().min(1).max(500),
    isCover: z.boolean().default(false),
    sizeMb: z.number().int().min(0).max(50).default(0),
  })).max(20).default([]),
  coverIcon: z.string().max(50).nullable().optional(),
  coverColor: z.string().max(50).nullable().optional(),
  isBatchCook: z.boolean().default(false),
  dishes: z.array(z.object({
    name: z.string().min(1).max(100),
    description: z.string().max(500).optional(),
    fridgeDays: z.number().int().min(1).max(14),
    freezerFriendly: z.boolean().default(false),
    freezerNote: z.string().max(300).optional(),
    dayOfInstructions: z.string().min(1).max(1000),
  })).max(10).default([]),
  // Manually-entered per-serving nutrition — takes precedence over (and
  // disables) the AI-estimate action on the recipe page, since re-estimating
  // would silently discard values the author entered on purpose.
  nutrition: z.object({
    calories: z.number().min(0).max(10000),
    proteinG: z.number().min(0).max(1000),
    carbsG: z.number().min(0).max(1000),
    fatG: z.number().min(0).max(1000),
    fiberG: z.number().min(0).max(1000),
    sodiumMg: z.number().min(0).max(100000),
  }).optional(),
});

export async function GET(req: NextRequest) {
  const { session, response } = await requireSessionOrApiKey(req, { rateLimit: { limit: 60, windowSeconds: 60 } });
  if (response) return response;

  const { searchParams } = new URL(req.url);
  const limit = Math.min(parseInt(searchParams.get("limit") ?? "20"), 100);
  const offset = parseInt(searchParams.get("offset") ?? "0");
  const visibility = searchParams.get("visibility") as "private" | "unlisted" | "public" | "followers" | null;
  const recipeType = searchParams.get("recipeType") as "dish" | "drink" | null;

  const conditions = [eq(recipes.authorId, session!.user.id)];
  if (visibility) conditions.push(eq(recipes.visibility, visibility));
  if (recipeType) conditions.push(eq(recipes.recipeType, recipeType));

  const rows = await db
    .select()
    .from(recipes)
    .where(and(...conditions))
    .orderBy(desc(recipes.updatedAt))
    .limit(limit)
    .offset(offset);

  return NextResponse.json({ data: rows, limit, offset });
}

export async function POST(req: NextRequest) {
  const { session, response } = await requireSessionOrApiKey(req, { rateLimit: { limit: 60, windowSeconds: 60 } });
  if (response) return response;

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

  const id = crypto.randomUUID();
  const now = new Date();
  const data = parsed.data;

  if (data.photos.some((p) => !isOwnedRecipePhotoKey(p.key, id, session!.user.id))) {
    return NextResponse.json({ error: "Validation error", issues: [{ path: ["photos"], message: "Photo key not issued for this recipe" }] }, { status: 400 });
  }

  const photosSizeMb = data.photos.reduce((sum, p) => sum + p.sizeMb, 0);

  try {
    await db.transaction(async (tx) => {
    await checkTierLimitInTransaction(tx, session!.user.id, session!.user.tier as "free" | "pro" | "family", "recipe");
    if (photosSizeMb > 0) {
      await checkTierLimitInTransaction(tx, session!.user.id, session!.user.tier as "free" | "pro" | "family", "storage", photosSizeMb);
    }
    await tx.insert(recipes).values({
      id,
      authorId: session!.user.id,
      title: data.title,
      description: data.description,
      baseServings: data.baseServings,
      recipeType: data.recipeType,
      visibility: data.visibility,
      difficulty: data.difficulty,
      prepMins: data.prepMins,
      cookMins: data.cookMins,
      tags: data.tags,
      dietaryTags: data.dietaryTags ?? {},
      aiGenerated: data.aiGenerated ?? false,
      language: data.language,
      sourceUrl: data.sourceUrl,
      coverIcon: data.coverIcon ?? null,
      coverColor: data.coverColor ?? null,
      isBatchCook: data.isBatchCook,
      nutritionData: data.nutrition ? { perServing: data.nutrition } : undefined,
      nutritionManual: !!data.nutrition,
      createdAt: now,
      updatedAt: now,
    });

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

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

    if (data.photos.length > 0) {
      await tx.insert(recipePhotos).values(
        data.photos.map((photo, i) => ({
          id: crypto.randomUUID(),
          recipeId: id,
          storageKey: photo.key,
          order: i,
          isCover: photo.isCover,
          sizeMb: photo.sizeMb,
        }))
      );
    }

    if (data.dishes.length > 0) {
      await tx.insert(recipeBatchDishes).values(
        data.dishes.map((dish, i) => ({
          id: crypto.randomUUID(),
          recipeId: id,
          name: dish.name,
          description: dish.description,
          order: i,
          fridgeDays: dish.fridgeDays,
          freezerFriendly: dish.freezerFriendly,
          freezerNote: dish.freezerNote,
          dayOfInstructions: dish.dayOfInstructions,
        }))
      );
    }
    });
  } catch (err) {
    if (err instanceof TierLimitError) {
      return NextResponse.json({ error: `${err.limit === "storage" ? "Storage" : "Recipe"} limit reached for your tier` }, { status: 403 });
    }
    throw err;
  }

  const recipe = await db.query.recipes.findFirst({ where: eq(recipes.id, id) });
  void dispatchWebhook(session!.user.id, "recipe.created", { id, title: data.title });
  return NextResponse.json(recipe, { status: 201 });
}