codetutor/frontend/src/app/questions/page.tsx

import { getQuestions, getCategories, getPatterns } from "@/lib/api";
import { QuestionCard } from "@/components/questions/question-card";
import Link from "next/link";

interface SearchParams {
  difficulty?: string;
  category?: string;
  pattern?: string;
  search?: string;
  page?: string;
}

export default async function QuestionsPage({
  searchParams,
}: {
  searchParams: Promise<SearchParams>;
}) {
  const params = await searchParams;
  const [questionsResponse, categoriesResponse, patternsResponse] =
    await Promise.all([
      getQuestions({
        difficulty: params.difficulty,
        category: params.category,
        pattern: params.pattern,
        search: params.search,
        page: params.page ? parseInt(params.page) : 1,
      }),
      getCategories(),
      getPatterns(),
    ]);

  const difficulties = ["easy", "medium", "hard"];

  return (
    <div className="space-y-6">
      <h1 className="text-3xl font-bold">Questions</h1>

      <div className="flex flex-wrap gap-4 p-4 rounded-lg bg-[var(--secondary)]">
        <div className="space-y-1">
          <label className="text-sm text-[var(--muted-foreground)]">
            Difficulty
          </label>
          <div className="flex gap-2">
            <Link
              href="/questions"
              className={`px-3 py-1 rounded text-sm ${
                !params.difficulty
                  ? "bg-[var(--primary)] text-[var(--primary-foreground)]"
                  : "bg-[var(--card)] hover:bg-[var(--muted)]"
              }`}
            >
              All
            </Link>
            {difficulties.map((d) => (
              <Link
                key={d}
                href={`/questions?difficulty=${d}`}
                className={`px-3 py-1 rounded text-sm capitalize ${
                  params.difficulty === d
                    ? "bg-[var(--primary)] text-[var(--primary-foreground)]"
                    : "bg-[var(--card)] hover:bg-[var(--muted)]"
                }`}
              >
                {d}
              </Link>
            ))}
          </div>
        </div>

        <div className="space-y-1">
          <label className="text-sm text-[var(--muted-foreground)]">
            Category
          </label>
          <select
            defaultValue={params.category || ""}
            className="px-3 py-1 rounded text-sm bg-[var(--card)] border border-[var(--border)]"
            onChange={(e) => {
              const url = new URL(window.location.href);
              if (e.target.value) {
                url.searchParams.set("category", e.target.value);
              } else {
                url.searchParams.delete("category");
              }
              window.location.href = url.toString();
            }}
          >
            <option value="">All Categories</option>
            {categoriesResponse.items.map((cat) => (
              <option key={cat.id} value={cat.slug}>
                {cat.name} ({cat.question_count})
              </option>
            ))}
          </select>
        </div>

        <div className="space-y-1">
          <label className="text-sm text-[var(--muted-foreground)]">
            Pattern
          </label>
          <select
            defaultValue={params.pattern || ""}
            className="px-3 py-1 rounded text-sm bg-[var(--card)] border border-[var(--border)]"
            onChange={(e) => {
              const url = new URL(window.location.href);
              if (e.target.value) {
                url.searchParams.set("pattern", e.target.value);
              } else {
                url.searchParams.delete("pattern");
              }
              window.location.href = url.toString();
            }}
          >
            <option value="">All Patterns</option>
            {patternsResponse.items.map((pat) => (
              <option key={pat.id} value={pat.slug}>
                {pat.name} ({pat.question_count})
              </option>
            ))}
          </select>
        </div>
      </div>

      <div className="text-sm text-[var(--muted-foreground)]">
        Showing {questionsResponse.items.length} of {questionsResponse.total}{" "}
        questions
      </div>

      <div className="grid gap-4">
        {questionsResponse.items.map((question) => (
          <QuestionCard key={question.id} question={question} />
        ))}
      </div>

      {questionsResponse.pages > 1 && (
        <div className="flex justify-center gap-2">
          {Array.from({ length: questionsResponse.pages }, (_, i) => i + 1).map(
            (page) => (
              <Link
                key={page}
                href={`/questions?page=${page}${
                  params.difficulty ? `&difficulty=${params.difficulty}` : ""
                }${params.category ? `&category=${params.category}` : ""}${
                  params.pattern ? `&pattern=${params.pattern}` : ""
                }`}
                className={`px-3 py-1 rounded ${
                  page === questionsResponse.page
                    ? "bg-[var(--primary)] text-[var(--primary-foreground)]"
                    : "bg-[var(--secondary)] hover:bg-[var(--muted)]"
                }`}
              >
                {page}
              </Link>
            )
          )}
        </div>
      )}
    </div>
  );
}