import { useState } from 'react'
import { Link, NavLink } from 'react-router-dom'
import { Menu, Moon, Sun, X } from 'lucide-react'
import { useTheme } from '@/components/theme-provider'
import { cn } from '@/lib/utils'

const NAV_ITEMS = [
  { label: '产品', to: '/', end: true },
  { label: '功能', to: '/#features' },
  { label: '架构', to: '/#architecture' },
  { label: '博客', to: '/blog' },
]

function ThemeToggle() {
  const { resolved, setTheme } = useTheme()
  return (
    <button
      type="button"
      aria-label={resolved === 'dark' ? '切换到浅色主题' : '切换到深色主题'}
      onClick={() => setTheme(resolved === 'dark' ? 'light' : 'dark')}
      className="flex size-8 items-center justify-center rounded-full border border-hairline-strong text-ink-2 transition-colors hover:border-accent hover:text-accent-ink"
    >
      {resolved === 'dark' ? (
        <Sun className="size-4" />
      ) : (
        <Moon className="size-4" />
      )}
    </button>
  )
}

export function SiteHeader() {
  const [open, setOpen] = useState(false)

  const links = NAV_ITEMS.map((item) =>
    item.to.includes('#') ? (
      <a
        key={item.to}
        href={item.to}
        onClick={() => setOpen(false)}
        className="text-sm text-ink-2 transition-colors hover:text-ink"
      >
        {item.label}
      </a>
    ) : (
      <NavLink
        key={item.to}
        to={item.to}
        end={item.end}
        onClick={() => setOpen(false)}
        className={({ isActive }) =>
          cn(
            'text-sm transition-colors hover:text-ink',
            isActive ? 'text-ink' : 'text-ink-2',
          )
        }
      >
        {item.label}
      </NavLink>
    ),
  )

  return (
    <header className="sticky top-0 z-40 border-b border-hairline bg-ground/85 backdrop-blur">
      <div className="mx-auto flex h-16 max-w-6xl items-center justify-between px-6 lg:px-10">
        <Link to="/" className="font-mono text-[15px] font-semibold">
          sundynix <em className="not-italic text-accent">agentix</em>
        </Link>

        <nav className="hidden items-center gap-7 md:flex">
          {links}
          <ThemeToggle />
          <Link
            to="/download"
            className="rounded-[7px] bg-accent px-4 py-1.5 text-[13px] font-medium text-ground transition-opacity hover:opacity-90"
          >
            下载桌面版
          </Link>
        </nav>

        <div className="flex items-center gap-3 md:hidden">
          <ThemeToggle />
          <button
            type="button"
            aria-label={open ? '关闭菜单' : '打开菜单'}
            onClick={() => setOpen((v) => !v)}
            className="flex size-8 items-center justify-center text-ink-2"
          >
            {open ? <X className="size-5" /> : <Menu className="size-5" />}
          </button>
        </div>
      </div>

      {open && (
        <nav className="flex flex-col gap-4 border-t border-hairline px-6 py-5 md:hidden">
          {links}
          <Link
            to="/download"
            onClick={() => setOpen(false)}
            className="w-fit rounded-[7px] bg-accent px-4 py-1.5 text-[13px] font-medium text-ground"
          >
            下载桌面版
          </Link>
        </nav>
      )}
    </header>
  )
}