import type { Metadata } from "next";
import { headers } from "next/headers";
import Link from "next/link";
import { auth } from "@/lib/auth/server";
import { db, recipes, sql, count } from "@epicure/db";
import { eq, desc, asc, and, ilike, or } from "@epicure/db";
import { RecipesHeader } from "@/components/recipe/recipes-header";
import { RecipesEmptyState } from "@/components/recipe/recipes-empty-state";
import { RecipesGrid } from "@/components/recipe/recipes-grid";

export const metadata: Metadata = {};

const PAGE_SIZE = 24;

type SearchParams = Promise<{
  q?: string;
  sort?: string;
  visibility?: string;
  difficulty?: string;
  tag?: string;
  page?: string;
}>;

const SORT_MAP = {
  updated_desc: desc(recipes.updatedAt),
  updated_asc: asc(recipes.updatedAt),
  created_desc: desc(recipes.createdAt),
  created_asc: asc(recipes.createdAt),
  title_asc: asc(recipes.title),
  title_desc: desc(recipes.title),
} as const;

type SortKey = keyof typeof SORT_MAP;

export default async function RecipesPage({ searchParams }: { searchParams: SearchParams }) {
  const session = await auth.api.getSession({ headers: await headers() });
  if (!session) return null;

  const { q, sort, visibility, difficulty, tag, page: pageParam } = await searchParams;
  const query = (q ?? "").trim().slice(0, 200);
  const sortKey: SortKey = (sort && sort in SORT_MAP ? sort : "updated_desc") as SortKey;
  const tagFilter = tag?.trim().slice(0, 50) || undefined;
  const page = Math.max(1, parseInt(pageParam ?? "1", 10) || 1);
  const offset = (page - 1) * PAGE_SIZE;

  const visibilityFilter = visibility && ["private", "unlisted", "public"].includes(visibility)
    ? (visibility as "private" | "unlisted" | "public")
    : undefined;
  const difficultyFilter = difficulty && ["easy", "medium", "hard"].includes(difficulty)
    ? (difficulty as "easy" | "medium" | "hard")
    : undefined;

  const where = and(
    eq(recipes.authorId, session.user.id),
    query
      ? or(ilike(recipes.title, `%${query}%`), ilike(recipes.description, `%${query}%`))
      : undefined,
    visibilityFilter ? eq(recipes.visibility, visibilityFilter) : undefined,
    difficultyFilter ? eq(recipes.difficulty, difficultyFilter) : undefined,
    tagFilter ? sql`${recipes.tags} @> ARRAY[${tagFilter}]::text[]` : undefined,
  );

  const [userRecipes, totalRow] = await Promise.all([
    db.query.recipes.findMany({
      where,
      orderBy: SORT_MAP[sortKey],
      with: { photos: true },
      limit: PAGE_SIZE,
      offset,
    }),
    db.select({ count: count() }).from(recipes).where(where),
  ]);

  const total = totalRow[0]?.count ?? 0;
  const totalPages = Math.max(1, Math.ceil(total / PAGE_SIZE));

  const pageHref = (p: number) => {
    const params = new URLSearchParams();
    if (query) params.set("q", query);
    if (sortKey !== "updated_desc") params.set("sort", sortKey);
    if (visibilityFilter) params.set("visibility", visibilityFilter);
    if (difficultyFilter) params.set("difficulty", difficultyFilter);
    if (tagFilter) params.set("tag", tagFilter);
    if (p > 1) params.set("page", String(p));
    const qs = params.toString();
    return qs ? `/recipes?${qs}` : "/recipes";
  };

  return (
    <div className="space-y-6">
      <RecipesHeader
        count={total}
        initialQuery={query}
        initialSort={sortKey}
        initialVisibility={visibilityFilter ?? ""}
        initialDifficulty={difficultyFilter ?? ""}
        initialTag={tagFilter ?? ""}
      />
      <RecipesEmptyState query={query} count={total} />
      <RecipesGrid key={`${query}-${sortKey}-${visibilityFilter}-${difficultyFilter}-${tagFilter}-${page}`} recipes={userRecipes} />

      {totalPages > 1 && (
        <div className="flex items-center justify-center gap-2 pt-2">
          {page > 1 && (
            <Link href={pageHref(page - 1)} className="rounded-md border px-3 py-1.5 text-sm hover:bg-accent">
              Previous
            </Link>
          )}
          <span className="text-sm text-muted-foreground px-2">
            Page {page} of {totalPages}
          </span>
          {page < totalPages && (
            <Link href={pageHref(page + 1)} className="rounded-md border px-3 py-1.5 text-sm hover:bg-accent">
              Next
            </Link>
          )}
        </div>
      )}
    </div>
  );
}
