import type { Metadata } from "next";
import { notFound } from "next/navigation";
import { headers } from "next/headers";
import Link from "next/link";
import { Globe } from "lucide-react";
import { auth } from "@/lib/auth/server";
import { db, shoppingLists, eq, and } from "@epicure/db";
import { buttonVariants } from "@/components/ui/button";
import { cn } from "@/lib/utils";
import { getMessages, formatMessage } from "@/lib/i18n/server";

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

export async function generateMetadata({ params }: Params): Promise<Metadata> {
  const { id } = await params;
  const list = await db.query.shoppingLists.findFirst({
    where: and(eq(shoppingLists.id, id), eq(shoppingLists.isPublic, true)),
  });
  if (!list) return {};
  return { title: list.name };
}

export default async function PublicShoppingListPage({ params }: Params) {
  const { id } = await params;
  const session = await auth.api.getSession({ headers: await headers() }).catch(() => null);
  const m = getMessages((session?.user as { locale?: string } | undefined)?.locale);
  const OTHER = m.mealPlan.aisleOther;

  const list = await db.query.shoppingLists.findFirst({
    where: and(eq(shoppingLists.id, id), eq(shoppingLists.isPublic, true)),
    with: { items: { orderBy: (t, { asc }) => [asc(t.aisle), asc(t.sortOrder), asc(t.rawName)] } },
  });

  if (!list) notFound();

  const byAisle = list.items.reduce<Record<string, typeof list.items>>((acc, item) => {
    const key = item.aisle ?? OTHER;
    (acc[key] ??= []).push(item);
    return acc;
  }, {});
  const aisles = Object.keys(byAisle).sort((a, b) => (a === OTHER ? 1 : b === OTHER ? -1 : a.localeCompare(b)));

  return (
    <div className="container mx-auto max-w-2xl px-4 py-8 space-y-6">
      <div className="flex items-center gap-2 text-sm text-muted-foreground">
        <Globe className="h-3.5 w-3.5" />
        <span>{m.publicShoppingList.sharedList}</span>
        {!session && (
          <div className="ml-auto flex items-center gap-2">
            <Link href="/signup" className={cn(buttonVariants({ size: "sm" }))}>{m.publicRecipe.signUpFree}</Link>
            <Link href="/login" className={cn(buttonVariants({ variant: "outline", size: "sm" }))}>{m.publicRecipe.logIn}</Link>
          </div>
        )}
      </div>

      <div>
        <h1 className="text-3xl font-bold tracking-tight">{list.name}</h1>
        <p className="text-muted-foreground mt-1">
          {formatMessage(m.shoppingLists.itemsChecked, {
            checked: list.items.filter((i) => i.checked).length,
            total: list.items.length,
          })}
        </p>
      </div>

      {aisles.map((aisle) => (
        <div key={aisle} className="space-y-2">
          {aisles.length > 1 && (
            <h2 className="text-xs font-semibold uppercase tracking-wide text-muted-foreground border-b pb-1">{aisle}</h2>
          )}
          <ul className="space-y-1.5">
            {byAisle[aisle]!.map((item) => (
              <li key={item.id} className="flex items-baseline gap-2 text-sm">
                <span
                  className={cn(
                    "inline-block h-4 w-4 shrink-0 rounded border translate-y-0.5",
                    item.checked ? "bg-foreground border-foreground" : "border-input"
                  )}
                />
                <span className="text-muted-foreground tabular-nums min-w-[3.5rem]">
                  {[item.quantity, item.unit].filter(Boolean).join(" ")}
                </span>
                <span className={cn(item.checked && "line-through text-muted-foreground")}>{item.rawName}</span>
              </li>
            ))}
          </ul>
        </div>
      ))}

      {!session && (
        <div className="rounded-xl border bg-muted/40 p-6 text-center space-y-3">
          <p className="font-semibold">{m.publicShoppingList.wantYourOwn}</p>
          <p className="text-sm text-muted-foreground">{m.publicRecipe.wantToSaveDescription}</p>
          <Link href="/signup" className={cn(buttonVariants())}>{m.publicRecipe.getStartedFree}</Link>
        </div>
      )}
    </div>
  );
}