"use client";

import { useState, useEffect } from "react";
import Link from "next/link";
import { useParams } from "next/navigation";
import { ThemeToggle } from "@/app/components/ThemeToggle";
import { getTopicConfig } from "../config";
import { isPaid } from "@/app/cloudphone/lib/payment";

type TopicHeaderProps = {
  topicId: string;
};

export function TopicHeader({ topicId }: TopicHeaderProps) {
  const [paid, setPaid] = useState(false);
  const config = getTopicConfig(topicId);

  useEffect(() => {
    setPaid(isPaid());
    const onPayUpdate = () => setPaid(isPaid());
    window.addEventListener("pay:updated", onPayUpdate);
    return () => window.removeEventListener("pay:updated", onPayUpdate);
  }, []);

  const ctaHref = config?.externalUrl
    ? config.externalUrl
    : paid
      ? "/cloudphone/course/0/0"
      : config?.payUrl ?? "/";

  return (
    <header
      className="fixed left-0 right-0 top-0 z-50 border-b border-[var(--border)] bg-[var(--background)]/95 backdrop-blur-xl"
      style={{ animationFillMode: "both" }}
    >
      <div className="mx-auto flex h-12 max-w-6xl items-center justify-between gap-2 px-3 sm:h-14 sm:gap-4 sm:px-4 md:h-16 md:px-6">
        <Link
          href="/"
          className="min-w-0 truncate text-sm font-medium text-[var(--foreground)] sm:text-base md:text-lg"
        >
          🌍 异度星球
        </Link>
        <nav className="flex shrink-0 items-center gap-1.5 sm:gap-3">
          <ThemeToggle />
          <Link
            href="/"
            className="text-sm text-[var(--muted-foreground)] transition hover:text-[var(--foreground)]"
          >
            首页
          </Link>
          <a
            href="https://chatwoot.hackrobot.cn/livechat?user_id=hackrobot"
            target="_blank"
            rel="noopener noreferrer"
            className="hidden items-center gap-1.5 rounded-full border border-[var(--accent)]/40 bg-[var(--accent)]/10 px-3 py-1.5 text-xs font-medium text-[var(--accent)] transition hover:bg-[var(--accent)]/20 sm:inline-flex sm:px-4 sm:py-2 sm:text-sm"
          >
            <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
              <path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z" />
            </svg>
            即时问答
          </a>
          <Link
            href={ctaHref}
            target={config?.externalUrl ? "_blank" : undefined}
            rel={config?.externalUrl ? "noopener noreferrer" : undefined}
            className="inline-flex items-center gap-1.5 rounded-full bg-[var(--accent)] px-3 py-1.5 text-xs font-medium text-[var(--accent-foreground)] transition hover:opacity-90 sm:px-4 sm:py-2 sm:text-sm"
          >
            {config?.externalUrl ? "前往了解 →" : paid ? "进入课程 →" : "立即报名 →"}
          </Link>
        </nav>
      </div>
    </header>
  );
}