'use client';

import React from 'react';
import Link from 'next/link';
import Image from 'next/image';
import { usePathname, useRouter } from 'next/navigation';
import { MessageSquare, Activity, Clock, Puzzle, Blocks, FolderOpen, Store, LogIn, UserPlus, Bot, ServerCog, Mail, LogOut, ChevronDown } from 'lucide-react';
import { logout } from '@/lib/api';
import { LanguageSwitcher } from '@/components/LanguageSwitcher';
import { Avatar, AvatarFallback } from '@/components/ui/avatar';
import { Button } from '@/components/ui/button';
import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
import { appConnectionStatusLabel } from '@/lib/i18n/common';
import { pickAppText } from '@/lib/i18n/core';
import { useAppI18n } from '@/lib/i18n/provider';
import { useChatStore } from '@/lib/store';

type NavItem = {
  key:
    | 'chat'
    | 'status'
    | 'office'
    | 'skills'
    | 'plugins'
    | 'agents'
    | 'mcp'
    | 'outlook'
    | 'marketplace'
    | 'files';
  href: string;
  icon: React.ComponentType<{ className?: string }>;
  matchPrefixes?: string[];
};

const NAV_ITEMS: NavItem[] = [
  { key: 'chat', href: '/', icon: MessageSquare },
  { key: 'status', href: '/status', icon: Activity },
  { key: 'office', href: '/office', icon: Clock, matchPrefixes: ['/office', '/cron'] },
  { key: 'skills', href: '/skills', icon: Puzzle },
  { key: 'plugins', href: '/plugins', icon: Blocks },
  { key: 'agents', href: '/agents', icon: Bot },
  { key: 'mcp', href: '/mcp', icon: ServerCog },
  { key: 'outlook', href: '/outlook', icon: Mail },
  { key: 'marketplace', href: '/marketplace', icon: Store },
  { key: 'files', href: '/files', icon: FolderOpen },
];

const AUTH_ITEMS = [
  { key: 'login', href: '/login', icon: LogIn },
  { key: 'register', href: '/register', icon: UserPlus },
] as const;

function ConnectionDot() {
  const { locale } = useAppI18n();
  const wsStatus = useChatStore((s) => s.wsStatus);
  const nanobotReady = useChatStore((s) => s.nanobotReady);

  const isOnline = wsStatus === 'connected' && nanobotReady === true;
  const isChecking = wsStatus === 'connected' && nanobotReady === null;
  const isConnecting = wsStatus === 'connecting' || isChecking;
  const isOffline = wsStatus === 'disconnected' || (wsStatus === 'connected' && nanobotReady === false);

  const color = isOnline
    ? 'bg-green-500'
    : isConnecting
      ? 'bg-yellow-500'
      : 'bg-red-500';

  const label = appConnectionStatusLabel(wsStatus, nanobotReady, locale);

  return (
    <div className="flex items-center gap-1.5 text-xs text-muted-foreground">
      <span className={`w-2 h-2 rounded-full ${color}`} />
      <span>{label}</span>
    </div>
  );
}

const Header = () => {
  const { locale } = useAppI18n();
  const pathname = usePathname();
  const router = useRouter();
  const user = useChatStore((s) => s.user);
  const isAuthLoading = useChatStore((s) => s.isAuthLoading);
  const setUser = useChatStore((s) => s.setUser);

  const navLabel = React.useCallback((key: NavItem['key']) => {
    if (key === 'chat') return pickAppText(locale, '对话', 'Chat');
    if (key === 'status') return pickAppText(locale, '状态', 'Status');
    if (key === 'office') return pickAppText(locale, '任务管理', 'Tasks');
    if (key === 'skills') return pickAppText(locale, '技能', 'Skills');
    if (key === 'plugins') return pickAppText(locale, '插件', 'Plugins');
    if (key === 'agents') return pickAppText(locale, '智能体', 'Agents');
    if (key === 'mcp') return 'MCP';
    if (key === 'outlook') return 'Outlook';
    if (key === 'marketplace') return pickAppText(locale, '市场', 'Marketplace');
    return pickAppText(locale, '文件', 'Files');
  }, [locale]);

  const authLabel = React.useCallback((key: 'login' | 'register') => (
    key === 'login'
      ? pickAppText(locale, '登录', 'Sign In')
      : pickAppText(locale, '注册', 'Sign Up')
  ), [locale]);

  const handleLogout = async () => {
    await logout();
    setUser(null);
    router.replace('/login');
    router.refresh();
  };

  const userInitial = (user?.username || user?.email || '?').trim().charAt(0).toUpperCase();

  return (
    <header className="fixed top-0 left-0 right-0 bg-background border-b border-border z-50">
      <div className="max-w-[1720px] mx-auto px-5 sm:px-6 lg:px-8 xl:px-10">
        <div className="flex items-center h-16 gap-6">
          <Link href="/" className="flex shrink-0 items-center gap-3 pr-2">
            <Image
              src="/boardware-logo.jpg"
              alt="Boardware logo"
              width={40}
              height={32}
              className="h-8 w-10 shrink-0 rounded-sm bg-white object-contain p-0.5"
            />
            <span className="whitespace-nowrap text-[1.05rem] font-semibold leading-none tracking-tight sm:text-[1.15rem]">
              Boardware Agent Sandbox
            </span>
          </Link>

          <div className="flex min-w-0 flex-1 items-center justify-end gap-3">
            <nav className="flex min-w-0 flex-1 items-center gap-1 overflow-x-auto whitespace-nowrap [scrollbar-width:none] [&::-webkit-scrollbar]:hidden">
              {NAV_ITEMS.map((item) => {
                const isActive =
                  item.href === '/'
                    ? pathname === '/'
                    : item.matchPrefixes?.some((prefix) => pathname.startsWith(prefix)) ?? pathname.startsWith(item.href);
                const Icon = item.icon;
                return (
                  <Link
                    key={item.href}
                    href={item.href}
                    className={`flex shrink-0 items-center gap-1.5 rounded-md px-3 py-2 text-sm font-medium transition-colors ${
                      isActive
                        ? 'bg-primary text-primary-foreground'
                        : 'text-muted-foreground hover:bg-accent hover:text-accent-foreground'
                    }`}
                  >
                    <Icon className="w-4 h-4" />
                    {navLabel(item.key)}
                  </Link>
                );
              })}
            </nav>

            <div className="flex shrink-0 items-center gap-2 border-l border-border pl-4">
              <LanguageSwitcher />
              {user ? (
                <Popover>
                  <PopoverTrigger asChild>
                    <button
                      type="button"
                      className="flex items-center gap-2 rounded-full border border-border/70 bg-background px-2 py-1.5 text-sm font-medium text-foreground transition-colors hover:bg-accent hover:text-accent-foreground"
                    >
                      <Avatar className="h-8 w-8 border border-border/60">
                        <AvatarFallback className="bg-primary text-xs font-semibold text-primary-foreground">
                          {userInitial}
                        </AvatarFallback>
                      </Avatar>
                      <span className="hidden max-w-28 truncate sm:block">{user.username}</span>
                      <ChevronDown className="h-4 w-4 text-muted-foreground" />
                    </button>
                  </PopoverTrigger>
                  <PopoverContent align="end" className="w-80 rounded-3xl border-border/70 p-0 shadow-2xl">
                    <div className="overflow-hidden rounded-3xl bg-gradient-to-b from-slate-50 via-slate-50 to-white">
                      <div className="border-b border-border/60 px-6 py-5">
                        <p className="truncate text-center text-sm font-medium text-muted-foreground">
                          {user.email}
                        </p>
                      </div>

                      <div className="flex flex-col items-center gap-4 px-6 py-6 text-center">
                        <Avatar className="h-24 w-24 border-4 border-white shadow-sm">
                          <AvatarFallback className="bg-primary text-4xl font-semibold text-primary-foreground">
                            {userInitial}
                          </AvatarFallback>
                        </Avatar>
                        <div className="space-y-1">
                          <p className="text-2xl font-semibold tracking-tight text-foreground">
                            {pickAppText(locale, `${user.username}，你好！`, `Hi, ${user.username}`)}
                          </p>
                          <p className="text-sm text-muted-foreground">
                            {pickAppText(locale, '当前已登录到你的工作区实例。', 'You are currently signed in to your workspace instance.')}
                          </p>
                        </div>
                      </div>

                      <div className="border-t border-border/60 bg-white/90 px-4 py-4">
                        <Button
                          type="button"
                          variant="outline"
                          onClick={handleLogout}
                          className="h-12 w-full justify-center rounded-2xl text-sm font-semibold"
                        >
                          <LogOut className="mr-2 h-4 w-4" />
                          {pickAppText(locale, '退出登录', 'Sign Out')}
                        </Button>
                      </div>
                    </div>
                  </PopoverContent>
                </Popover>
              ) : !isAuthLoading ? (
                AUTH_ITEMS.map((item) => {
                  const isActive = pathname.startsWith(item.href);
                  const Icon = item.icon;
                  return (
                    <Link
                      key={item.href}
                      href={item.href}
                      className={`flex items-center gap-1.5 rounded-md px-3 py-2 text-sm font-medium transition-colors ${
                        isActive
                          ? 'bg-primary text-primary-foreground'
                          : 'text-muted-foreground hover:bg-accent hover:text-accent-foreground'
                      }`}
                    >
                      <Icon className="w-4 h-4" />
                      {authLabel(item.key)}
                    </Link>
                  );
                })
              ) : null}
            </div>

            <div className="shrink-0 border-l border-border pl-4">
              <ConnectionDot />
            </div>
          </div>
        </div>
      </div>
    </header>
  );
};

export default Header;