"use client";

import { useState, useEffect } from "react";
import { VideoCard } from "./VideoCard";
import { useVideoProgress } from "./useVideoProgress";
import AuthModal from "../components/AuthModal";

function getStoredUser(): string | null {
  if (typeof window === "undefined") return null;
  try {
    const raw = localStorage.getItem("pb_user");
    if (!raw) return null;
    const user = JSON.parse(raw);
    return user?.email ?? null;
  } catch {
    return null;
  }
}

/* ─── data ─── */

const stats = [
  { value: "21", label: "节实战课程" },
  { value: "150+", label: "分钟视频" },
  { value: "3", label: "位实战讲师" },
];

const audiences = [
  {
    icon: "💼",
    title: "职场人想转型",
    desc: "受够了 996？学会远程工作技能，平滑过渡到自由生活方式",
  },
  {
    icon: "👨‍💻",
    title: "开发者 / 设计师",
    desc: "你的技能天然适合远程，学会如何接全球客户、拿美金报酬",
  },
  {
    icon: "📱",
    title: "自媒体 / 内容创作者",
    desc: "边旅行边创作，掌握数字游民内容变现的全套方法论",
  },
  {
    icon: "🌍",
    title: "想出国旅居的人",
    desc: "签证、税务、保险、目的地一站搞定，少走弯路直接出发",
  },
];

const benefits = [
  {
    num: 1,
    title: "完整的远程工作体系",
    desc: "从技能评估到客户获取，建立可持续的远程收入系统",
  },
  {
    num: 2,
    title: "打通 3+ 收入渠道",
    desc: "远程全职、自由职业、数字产品、内容创作多管齐下",
  },
  {
    num: 3,
    title: "掌握 50+ 远程工具",
    desc: "协作、会议、项目管理、财务，一个背包装下整个办公室",
  },
  {
    num: 4,
    title: "签证 + 税务 + 保险全通关",
    desc: "55 国数字游民签证政策、合规税务方案、保险选购指南",
  },
  {
    num: 5,
    title: "跑通第一次数字游民旅程",
    desc: "从选目的地到打包出发，手把手带你完成首次数字游民体验",
  },
];

// 示例视频：w3schools 公开样本，可替换为 MinIO CDN URL（如 https://minioweb.hackrobot.cn/hackrobot/course/xxx.mp4）
const SAMPLE_VIDEO = "https://www.w3schools.com/html/mov_bbb.mp4";

// 一级：part 二级：section 三级：lesson
const curriculum = [
  {
    emoji: "🚀",
    part: "基础篇",
    sections: [
      { name: "认识数字游民", lessons: [{ id: "01", title: "什么是数字游民？破除 5 个常见误解", duration: "12:30", videoUrl: SAMPLE_VIDEO }, { id: "02", title: "数字游民三种模式：蜜蜂、乌龟、候鸟", duration: "08:45", videoUrl: SAMPLE_VIDEO }] },
    ],
  },
  {
    emoji: "💡",
    part: "技能篇",
    sections: [
      { name: "远程工作能力", lessons: [{ id: "03", title: "远程高薪技能全景图：找到你的方向", duration: "14:20", videoUrl: SAMPLE_VIDEO }, { id: "04", title: "30天技能升级路线：从评估到接单", duration: "11:15", videoUrl: SAMPLE_VIDEO }, { id: "05", title: "建立个人品牌：让客户主动找你", duration: "09:40", videoUrl: SAMPLE_VIDEO }] },
    ],
  },
  {
    emoji: "💰",
    part: "收入篇",
    sections: [
      { name: "构建收入体系", lessons: [{ id: "06", title: "远程全职 vs 自由职业：选哪条路？", duration: "10:05", videoUrl: SAMPLE_VIDEO }, { id: "07", title: "自由职业平台实操：Upwork / Toptal / 电鸭", duration: "13:50", videoUrl: SAMPLE_VIDEO }, { id: "08", title: "被动收入搭建：数字产品 & 在线课程", duration: "12:20", videoUrl: SAMPLE_VIDEO }, { id: "09", title: "定价的艺术：如何报价不心虚", duration: "07:30", videoUrl: SAMPLE_VIDEO }] },
    ],
  },
  {
    emoji: "🛠️",
    part: "工具篇",
    sections: [
      { name: "移动办公装备", lessons: [{ id: "10", title: "硬件极简主义：一个背包装下办公室", duration: "06:45", videoUrl: SAMPLE_VIDEO }, { id: "11", title: "远程协作工具栈：Slack / Notion / Linear", duration: "08:30", videoUrl: SAMPLE_VIDEO }, { id: "12", title: "安全必修课：VPN / 密码管理 / 2FA", duration: "05:55", videoUrl: SAMPLE_VIDEO }, { id: "13", title: "跨境财务工具：Wise / Stripe / Revolut", duration: "07:10", videoUrl: SAMPLE_VIDEO }] },
    ],
  },
  {
    emoji: "📋",
    part: "合规篇",
    sections: [
      { name: "签证税务保险", lessons: [{ id: "14", title: "55 国数字游民签证政策全解读", duration: "15:30", videoUrl: SAMPLE_VIDEO }, { id: "15", title: "税务居民身份与合规规划", duration: "11:40", videoUrl: SAMPLE_VIDEO }, { id: "16", title: "数字游民保险选购指南", duration: "06:20", videoUrl: SAMPLE_VIDEO }] },
    ],
  },
  {
    emoji: "🗺️",
    part: "目的地篇",
    sections: [
      { name: "选择你的城市", lessons: [{ id: "17", title: "亚洲三城：清迈 / 巴厘岛 / 首尔深度对比", duration: "10:50", videoUrl: SAMPLE_VIDEO }, { id: "18", title: "欧洲双雄：里斯本 / 巴塞罗那生活实录", duration: "09:25", videoUrl: SAMPLE_VIDEO }, { id: "19", title: "美洲探索：墨西哥城 / 麦德林旅居指南", duration: "08:15", videoUrl: SAMPLE_VIDEO }] },
    ],
  },
  {
    emoji: "🏆",
    part: "实战篇",
    sections: [
      { name: "启程出发", lessons: [{ id: "20", title: "出发前检查清单 & 打包哲学", duration: "07:40", videoUrl: SAMPLE_VIDEO }, { id: "21", title: "第一个月生存指南 & 长期可持续策略", duration: "13:10", videoUrl: SAMPLE_VIDEO }] },
    ],
  },
];

const instructors = [
  {
    name: "Alex",
    avatar: "🧑‍💻",
    role: "全栈开发者 / 5年数字游民",
    tag: "技术导师",
    desc: "前字节跳动高级工程师，2021年开始数字游民生活，足迹遍布 20+ 国家，远程服务硅谷客户",
  },
  {
    name: "Lisa",
    avatar: "👩‍🎨",
    role: "品牌设计师 / 自由职业教练",
    tag: "变现专家",
    desc: "Toptal 认证设计师，年收入 $120K+，帮助 500+ 人成功转型远程自由职业",
  },
  {
    name: "Marco",
    avatar: "🧳",
    role: "旅居作家 / 签证顾问",
    tag: "旅居达人",
    desc: "常驻里斯本，持有 3 国数字游民签证，《数字游民签证手册》作者，深谙各国政策",
  },
];

/* ─── component ─── */

export default function CoursePage() {
  const [modalOpen, setModalOpen] = useState(false);
  const [authOpen, setAuthOpen] = useState(false);
  const [userEmail, setUserEmail] = useState<string | null>(null);
  const [expandedPart, setExpandedPart] = useState<string | null>(null);
  const { markCompleted, isCompleted, isPartCompleted } = useVideoProgress();

  useEffect(() => {
    setUserEmail(getStoredUser());
  }, []);

  const handleLogout = () => {
    localStorage.removeItem("pb_token");
    localStorage.removeItem("pb_user");
    setUserEmail(null);
  };

  return (
    <div className="min-h-screen bg-white text-slate-900">
      {/* ── Nav ── */}
      <header className="sticky top-0 z-50 border-b border-slate-100 bg-white/80 backdrop-blur-lg">
        <div className="mx-auto flex h-14 max-w-5xl items-center justify-between gap-3 px-4 sm:px-6">
          <a href="/" className="flex items-center gap-2 text-sm font-bold">
            <span className="text-lg">🌍</span>
            数字游民指南
          </a>
          <div className="flex items-center gap-2 sm:gap-3">
            {userEmail ? (
              <>
                <span className="hidden max-w-[120px] truncate text-sm text-slate-600 sm:inline">
                  {userEmail}
                </span>
                <button
                  onClick={handleLogout}
                  className="rounded-full border border-slate-200 px-3 py-1.5 text-sm font-medium text-slate-600 transition-colors hover:bg-slate-50"
                >
                  退出
                </button>
              </>
            ) : (
              <button
                onClick={() => setAuthOpen(true)}
                className="rounded-full border border-slate-200 px-3 py-1.5 text-sm font-medium text-slate-600 transition-colors hover:bg-slate-50"
              >
                登录 / 注册
              </button>
            )}
            <button
              onClick={() => setModalOpen(true)}
              className="rounded-full bg-sky-500 px-4 py-1.5 text-sm font-semibold text-white transition-colors hover:bg-sky-600"
            >
              立即报名
            </button>
          </div>
        </div>
      </header>

      {/* ── Hero ── */}
      <section className="relative overflow-hidden bg-gradient-to-b from-slate-50 to-white py-20 sm:py-28">
        <div className="pointer-events-none absolute top-0 left-1/2 h-[500px] w-[700px] -translate-x-1/2 rounded-full bg-gradient-to-br from-sky-100/50 via-cyan-50/30 to-amber-50/20 blur-3xl" />
        <div className="relative mx-auto max-w-3xl px-4 text-center sm:px-6">
          <h1 className="text-4xl font-extrabold tracking-tight sm:text-5xl lg:text-6xl">
            <span className="gradient-text">数字游民</span>实战课
          </h1>
          <p className="mx-auto mt-5 max-w-xl text-lg leading-relaxed text-slate-600 sm:text-xl">
            7天打造你的远程工作体系与自由生活方式
          </p>

          <div className="mt-10 flex items-center justify-center gap-6 sm:gap-10">
            {stats.map((s) => (
              <div key={s.label} className="text-center">
                <div className="text-3xl font-extrabold text-sky-600 sm:text-4xl">
                  {s.value}
                </div>
                <div className="mt-1 text-sm text-slate-500">{s.label}</div>
              </div>
            ))}
          </div>

          <button
            onClick={() => setModalOpen(true)}
            className="mt-10 inline-flex items-center gap-2 rounded-full bg-sky-500 px-10 py-4 text-lg font-semibold text-white shadow-lg shadow-sky-500/25 transition-all hover:bg-sky-600 hover:shadow-xl hover:shadow-sky-500/30"
          >
            立即报名
            <span>→</span>
          </button>
        </div>
      </section>

      {/* ── Audience ── */}
      <section className="py-20 sm:py-24">
        <div className="mx-auto max-w-5xl px-4 sm:px-6">
          <h2 className="text-center text-2xl font-bold sm:text-3xl">
            这门课适合谁？
          </h2>
          <p className="mx-auto mt-3 max-w-xl text-center text-slate-500">
            不管你是什么背景，只要想拥有地点自由的生活
          </p>

          <div className="mt-14 grid gap-6 sm:grid-cols-2 lg:grid-cols-4">
            {audiences.map((a) => (
              <div
                key={a.title}
                className="card-hover rounded-2xl border border-slate-100 bg-white p-6 text-center shadow-sm"
              >
                <div className="mx-auto mb-4 flex h-14 w-14 items-center justify-center rounded-2xl bg-sky-50 text-3xl">
                  {a.icon}
                </div>
                <h3 className="mb-2 font-bold">{a.title}</h3>
                <p className="text-sm leading-relaxed text-slate-500">
                  {a.desc}
                </p>
              </div>
            ))}
          </div>
        </div>
      </section>

      {/* ── Benefits ── */}
      <section className="bg-slate-50 py-20 sm:py-24">
        <div className="mx-auto max-w-5xl px-4 sm:px-6">
          <h2 className="text-center text-2xl font-bold sm:text-3xl">
            学完你将获得
          </h2>
          <p className="mx-auto mt-3 max-w-xl text-center text-slate-500">
            5 大核心收益，助你顺利开启数字游民生活
          </p>

          <div className="mt-14 space-y-5">
            {benefits.map((b) => (
              <div
                key={b.num}
                className="card-hover flex items-start gap-5 rounded-2xl border border-slate-100 bg-white p-6 shadow-sm sm:items-center"
              >
                <div className="flex h-12 w-12 shrink-0 items-center justify-center rounded-xl bg-gradient-to-br from-sky-500 to-cyan-500 text-xl font-extrabold text-white shadow-md shadow-sky-500/20">
                  {b.num}
                </div>
                <div>
                  <h3 className="text-lg font-bold text-slate-900">{b.title}</h3>
                  <p className="mt-1 text-sm text-slate-500">{b.desc}</p>
                </div>
              </div>
            ))}
          </div>
        </div>
      </section>

      {/* ── Curriculum ── 参考：垂直时间线 + 学习路径视觉 */}
      <section className="relative overflow-hidden bg-gradient-to-b from-white via-slate-50/50 to-slate-50 py-24 sm:py-28">
        <div className="mx-auto max-w-4xl px-4 sm:px-6">
          {/* 标题区：大数字 + 学习路径感 */}
          <div className="mb-16 text-center">
            <div className="inline-flex items-baseline gap-2">
              <span className="gradient-text text-6xl font-extrabold tabular-nums tracking-tight sm:text-7xl">
                21
              </span>
              <span className="text-2xl font-bold text-slate-800 sm:text-3xl">
                节实战课程
              </span>
            </div>
            <p className="mt-4 text-slate-500">
              从入门到启程 · 完整的学习路径
            </p>
            <div className="mx-auto mt-6 h-px w-24 rounded-full bg-gradient-to-r from-transparent via-sky-300/60 to-transparent" />
          </div>

          {/* 垂直时间线：左侧竖线 + 节点 */}
          <div className="relative">
            {/* 中央竖线 */}
            <div
              className="absolute left-[19px] top-6 bottom-6 w-0.5 bg-gradient-to-b from-sky-200/80 via-sky-300/60 to-sky-200/80 sm:left-[23px]"
              aria-hidden
            />

            <div className="space-y-0">
              {curriculum.map((ch, idx) => {
                const allLessons = ch.sections.flatMap((s) => s.lessons);
                const partCompleted = isPartCompleted(allLessons.map((l) => l.id));
                const isExpanded = expandedPart === ch.part;
                const totalLessons = allLessons.length;
                return (
                  <div key={ch.part} className="relative flex gap-6 pb-10 last:pb-0">
                    {/* 左侧节点圆：完成时显示 ✓ */}
                    <div className="relative z-10 flex shrink-0 items-start pt-0.5">
                      <div
                        className={`flex h-10 w-10 shrink-0 items-center justify-center rounded-full text-sm font-bold shadow-sm transition-colors sm:h-12 sm:w-12 ${
                          partCompleted
                            ? "border-2 border-emerald-300 bg-emerald-50 text-emerald-600"
                            : "border-2 border-sky-200 bg-white text-sky-600"
                        }`}
                      >
                        {partCompleted ? (
                          <svg className="h-5 w-5 sm:h-6 sm:w-6" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2.5}>
                            <path strokeLinecap="round" strokeLinejoin="round" d="M5 13l4 4L19 7" />
                          </svg>
                        ) : (
                          idx + 1
                        )}
                      </div>
                    </div>

                    {/* 右侧内容卡片 */}
                    <div className="min-w-0 flex-1">
                      <div
                        className={`overflow-hidden rounded-2xl border shadow-sm transition-colors ${
                          partCompleted ? "border-emerald-200/80 bg-emerald-50/30" : "border-slate-200/80 bg-white"
                        }`}
                      >
                        {/* 一级：Part 标题，点击展开/收起 */}
                        <button
                          type="button"
                          onClick={() => setExpandedPart(isExpanded ? null : ch.part)}
                          className="flex w-full items-center justify-between gap-3 px-5 py-4 text-left transition-colors hover:bg-slate-50/80 sm:px-6"
                        >
                          <div className="flex items-center gap-3">
                            <span className="text-2xl">{ch.emoji}</span>
                            <h3 className="font-bold text-slate-800">{ch.part}</h3>
                            {partCompleted && (
                              <span className="rounded-full bg-emerald-100 px-2 py-0.5 text-xs font-medium text-emerald-700">
                                已完成
                              </span>
                            )}
                          </div>
                          <span className="flex items-center gap-2 text-sm text-slate-400">
                            <span>{totalLessons} 节</span>
                            <svg
                              className={`h-4 w-4 shrink-0 transition-transform duration-200 ${
                                isExpanded ? "rotate-180" : ""
                              }`}
                              fill="none"
                              viewBox="0 0 24 24"
                              stroke="currentColor"
                            >
                              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 9l-7 7-7-7" />
                            </svg>
                          </span>
                        </button>

                        {/* 展开后：二级 section + 三级 lesson */}
                        {isExpanded && (
                          <div className="border-t border-slate-100 bg-slate-50/40">
                            {ch.sections.map((sec) => (
                              <div key={sec.name} className="border-b border-slate-100 last:border-b-0">
                                {/* 二级标题 */}
                                <div className="flex items-center gap-3 border-b border-slate-100/80 bg-slate-50/60 px-5 py-3.5 sm:px-6">
                                  <span className="flex h-6 w-1 shrink-0 rounded-full bg-gradient-to-b from-sky-400 to-sky-500" />
                                  <h4 className="text-sm font-semibold text-slate-700">
                                    {sec.name}
                                  </h4>
                                  <span className="rounded-full bg-slate-200/60 px-2 py-0.5 text-xs font-medium text-slate-500">
                                    {sec.lessons.length} 节
                                  </span>
                                </div>
                                {/* 三级：视频卡片网格 */}
                                <div className="grid gap-5 p-5 sm:grid-cols-2 sm:p-6 lg:grid-cols-3">
                                  {sec.lessons.map((lesson) => (
                                    <VideoCard
                                      key={lesson.id}
                                      lesson={lesson as { id: string; title: string; duration: string; videoUrl?: string }}
                                      completed={isCompleted(lesson.id)}
                                      onComplete={() => markCompleted(lesson.id)}
                                    />
                                  ))}
                                </div>
                              </div>
                            ))}
                          </div>
                        )}
                      </div>
                    </div>
                  </div>
                );
              })}
            </div>
          </div>
        </div>
      </section>

      {/* ── Instructors ── */}
      <section className="bg-slate-50 py-20 sm:py-24">
        <div className="mx-auto max-w-5xl px-4 sm:px-6">
          <h2 className="text-center text-2xl font-bold sm:text-3xl">
            三位实战讲师联合授课
          </h2>
          <p className="mx-auto mt-3 max-w-xl text-center text-slate-500">
            真正的数字游民亲自带你上手
          </p>

          <div className="mt-14 grid gap-6 sm:grid-cols-3">
            {instructors.map((ins) => (
              <div
                key={ins.name}
                className="card-hover rounded-2xl border border-slate-100 bg-white p-6 text-center shadow-sm"
              >
                <div className="mx-auto mb-4 flex h-20 w-20 items-center justify-center rounded-full bg-gradient-to-br from-sky-100 to-cyan-50 text-5xl">
                  {ins.avatar}
                </div>
                <h3 className="text-lg font-bold">{ins.name}</h3>
                <p className="mt-1 text-sm text-slate-500">{ins.role}</p>
                <span className="mt-3 inline-block rounded-full bg-sky-50 px-3 py-1 text-xs font-semibold text-sky-600">
                  {ins.tag}
                </span>
                <p className="mt-4 text-sm leading-relaxed text-slate-500">
                  {ins.desc}
                </p>
              </div>
            ))}
          </div>
        </div>
      </section>

      {/* ── Final CTA ── */}
      <section className="py-20 sm:py-28">
        <div className="mx-auto max-w-3xl px-4 text-center sm:px-6">
          <h2 className="text-2xl font-bold sm:text-3xl">
            准备好开启你的数字游民生活了吗？
          </h2>
          <p className="mx-auto mt-4 max-w-lg text-slate-500">
            加入我们，跟着实战讲师一起，从零开始规划属于你的自由生活
          </p>

          <div className="mt-8 flex flex-wrap items-center justify-center gap-4 text-sm text-slate-500">
            <span className="rounded-full border border-slate-200 bg-white px-4 py-1.5">
              21节实战视频
            </span>
            <span className="rounded-full border border-slate-200 bg-white px-4 py-1.5">
              永久回看
            </span>
            <span className="rounded-full border border-slate-200 bg-white px-4 py-1.5">
              社群答疑
            </span>
          </div>

          <button
            onClick={() => setModalOpen(true)}
            className="mt-10 inline-flex items-center gap-2 rounded-full bg-sky-500 px-10 py-4 text-lg font-semibold text-white shadow-lg shadow-sky-500/25 transition-all hover:bg-sky-600 hover:shadow-xl hover:shadow-sky-500/30"
          >
            立即加入
            <span>→</span>
          </button>
        </div>
      </section>

      {/* ── Footer ── */}
      <footer className="border-t border-slate-100 bg-white py-8 text-center text-sm text-slate-400">
        <a href="/" className="font-medium text-slate-600 transition-colors hover:text-sky-600">
          🌍 数字游民指南
        </a>
        <span className="mx-2">·</span>
        开源免费 · 社区驱动
      </footer>

      <AuthModal
        isOpen={authOpen}
        onClose={() => setAuthOpen(false)}
        onSuccess={(email) => setUserEmail(email)}
      />

      {/* ── 报名 Modal ── */}
      {modalOpen && (
        <div
          className="fixed inset-0 z-[100] flex items-center justify-center bg-black/50 p-4 backdrop-blur-sm"
          onClick={() => setModalOpen(false)}
        >
          <div
            className="relative w-full max-w-sm animate-fade-in rounded-2xl bg-white p-8 shadow-2xl"
            onClick={(e) => e.stopPropagation()}
          >
            <button
              onClick={() => setModalOpen(false)}
              className="absolute top-4 right-4 flex h-8 w-8 items-center justify-center rounded-full text-slate-400 transition-colors hover:bg-slate-100 hover:text-slate-600"
            >
              <svg className="h-5 w-5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M6 18L18 6M6 6l12 12" />
              </svg>
            </button>

            <h3 className="text-center text-lg font-bold">
              数字游民实战课
            </h3>
            <p className="mt-1 text-center text-sm text-slate-500">
              7天打造你的远程工作体系
            </p>

            <div className="mt-6 rounded-xl border border-slate-100 bg-slate-50 p-6 text-center">
              <div className="text-6xl">🌍</div>
              <p className="mt-3 text-sm font-medium text-slate-600">
                扫码报名
              </p>
              <p className="mt-4 text-3xl font-extrabold text-sky-600">¥199</p>
              <p className="mt-1 text-xs text-slate-400">
                微信扫码 · 小程序购买
              </p>
            </div>

            <div className="mt-5 rounded-xl border border-slate-100 bg-slate-50 p-4 text-center">
              <div className="text-4xl">💬</div>
              <p className="mt-2 text-sm font-medium text-slate-600">
                添加微信进群
              </p>
              <p className="mt-1 text-xs text-slate-400">
                交流答疑 · 文档资料 · 权益通知
              </p>
            </div>
          </div>
        </div>
      )}
    </div>
  );
}