import { useState, useRef, useEffect, useMemo } from 'react'
import { useLocation, useNavigate } from 'react-router-dom'
import { Search, Bell, ChevronDown, User, Palette, LogOut, Shield, HelpCircle, Server, Bookmark as BookmarkIcon, LayoutGrid } from 'lucide-react'
import { useAuth } from '../lib/AuthContext'
import { api } from '../lib/api'

const pageTitles: Record<string, string> = {
  '/': 'Glance',
  '/infrastructure': 'Infrastructure',
  '/booknest': 'BookNest',
  '/terminal': 'Terminal',
  '/tunnels': 'Tunnels',
  '/files': 'Files',
  '/containers': 'Containers',
  '/remote-desktop': 'Remote Desktop',
  '/host-metrics': 'Host Metrics',
  '/settings': 'Settings',
  '/help': 'Help',
}

const pageSubtitles: Record<string, string> = {
  '/booknest': 'Your Digital Library',
}

const staticPages: { name: string; path: string }[] = [
  { name: 'Glance', path: '/' },
  { name: 'Infrastructure', path: '/infrastructure' },
  { name: 'BookNest', path: '/booknest' },
  { name: 'Terminal', path: '/terminal' },
  { name: 'Tunnels', path: '/tunnels' },
  { name: 'Files', path: '/files' },
  { name: 'Containers', path: '/containers' },
  { name: 'Remote Desktop', path: '/remote-desktop' },
  { name: 'Host Metrics', path: '/host-metrics' },
  { name: 'Settings', path: '/settings' },
  { name: 'Help', path: '/help' },
]

type SearchResult =
  | { kind: 'page'; key: string; label: string; sublabel?: string; path: string }
  | { kind: 'integration'; key: string; label: string; sublabel?: string; path: string }
  | { kind: 'bookmark'; key: string; label: string; sublabel?: string; path: string }

export default function TopBar() {
  const { logout, user } = useAuth()
  const [userMenuOpen, setUserMenuOpen] = useState(false)
  const menuRef = useRef<HTMLDivElement>(null)
  const location = useLocation()
  const navigate = useNavigate()
  const title = pageTitles[location.pathname] ?? 'Glance'
  const subtitle = pageSubtitles[location.pathname]

  const [query, setQuery] = useState('')
  const [searchOpen, setSearchOpen] = useState(false)
  const [integrations, setIntegrations] = useState<{ id: number; name: string; type: string }[]>([])
  const [bookmarks, setBookmarks] = useState<{ id: number; title: string; url: string }[]>([])
  const searchRef = useRef<HTMLDivElement>(null)

  useEffect(() => {
    api.listIntegrations().then(({ integrations }) => setIntegrations(integrations)).catch(() => {})
    api.listBookmarks().then(({ bookmarks }) => setBookmarks(bookmarks)).catch(() => {})
  }, [])

  useEffect(() => {
    function handleClick(e: MouseEvent) {
      if (searchRef.current && !searchRef.current.contains(e.target as Node)) {
        setSearchOpen(false)
      }
    }
    document.addEventListener('mousedown', handleClick)
    return () => document.removeEventListener('mousedown', handleClick)
  }, [])

  const results = useMemo<SearchResult[]>(() => {
    const q = query.trim().toLowerCase()
    if (!q) return []
    const pageMatches: SearchResult[] = staticPages
      .filter((p) => p.name.toLowerCase().includes(q))
      .map((p) => ({ kind: 'page', key: `page-${p.path}`, label: p.name, path: p.path }))
    const integrationMatches: SearchResult[] = integrations
      .filter((i) => i.name.toLowerCase().includes(q) || i.type.toLowerCase().includes(q))
      .map((i) => ({ kind: 'integration', key: `int-${i.id}`, label: i.name, sublabel: i.type, path: '/infrastructure' }))
    const bookmarkMatches: SearchResult[] = bookmarks
      .filter((b) => b.title.toLowerCase().includes(q) || b.url.toLowerCase().includes(q))
      .map((b) => ({ kind: 'bookmark', key: `bm-${b.id}`, label: b.title, sublabel: b.url, path: '/booknest' }))
    return [...pageMatches, ...integrationMatches, ...bookmarkMatches].slice(0, 8)
  }, [query, integrations, bookmarks])

  function handleSelectResult(r: SearchResult) {
    navigate(r.path)
    setQuery('')
    setSearchOpen(false)
  }

  const displayName = user?.display_name || user?.username || ''
  const initials = displayName
    .split(/\s+/)
    .map((p) => p[0])
    .join('')
    .slice(0, 2)
    .toUpperCase()

  useEffect(() => {
    function handleClick(e: MouseEvent) {
      if (menuRef.current && !menuRef.current.contains(e.target as Node)) {
        setUserMenuOpen(false)
      }
    }
    document.addEventListener('mousedown', handleClick)
    return () => document.removeEventListener('mousedown', handleClick)
  }, [])

  return (
    <header className="flex items-center px-6 sticky top-0 z-40" style={{ height: subtitle ? '72px' : '56px' }}>
      {/* Page Title — pushed away from sidebar edge */}
      <div style={{ marginLeft: '20px' }}>
        <h1
          className="font-bold uppercase tracking-wide"
          style={{ color: '#C8A434', fontSize: subtitle ? '28px' : '18px' }}
        >
          {title}
        </h1>
        {subtitle && (
          <p className="text-[13px]" style={{ color: '#A8A6A0', marginTop: '2px' }}>
            {subtitle}
          </p>
        )}
      </div>

      {/* Center section — Search bar */}
      <div className="flex-1 flex justify-center">
        <div className="relative" ref={searchRef}>
          <Search size={14} className="absolute left-3 top-1/2 -translate-y-1/2" style={{ color: '#7A7D85' }} />
          <input
            type="text"
            placeholder="Search resources..."
            value={query}
            onChange={(e) => {
              setQuery(e.target.value)
              setSearchOpen(true)
            }}
            onFocus={() => setSearchOpen(true)}
            onKeyDown={(e) => {
              if (e.key === 'Enter' && results.length > 0) {
                handleSelectResult(results[0])
              } else if (e.key === 'Escape') {
                setSearchOpen(false)
              }
            }}
            className="w-[300px] h-8 rounded-full border border-border text-[12px] text-text-primary placeholder:text-text-secondary focus:outline-none focus:border-gold transition-colors"
            style={{ paddingLeft: '36px', paddingRight: '16px', backgroundColor: 'rgba(255,255,255,0.04)', backdropFilter: 'blur(6px)' }}
          />

          {searchOpen && query.trim() && (
            <div className="absolute left-0 top-full mt-2 w-[320px] bg-card border border-border rounded-xl overflow-hidden shadow-lg z-50">
              {results.length === 0 ? (
                <div className="px-3 py-3 text-[12px]" style={{ color: '#7A7D85' }}>
                  No matches for "{query}"
                </div>
              ) : (
                <div className="py-1 max-h-[280px] overflow-y-auto">
                  {results.map((r) => (
                    <button
                      key={r.key}
                      onClick={() => handleSelectResult(r)}
                      className="flex w-full items-center gap-2.5 px-3 py-2 text-[12px] text-text-secondary hover:text-text-primary hover:bg-page transition-colors cursor-pointer border-none bg-transparent text-left"
                    >
                      {r.kind === 'page' && <LayoutGrid size={14} />}
                      {r.kind === 'integration' && <Server size={14} />}
                      {r.kind === 'bookmark' && <BookmarkIcon size={14} />}
                      <span className="flex flex-col">
                        <span>{r.label}</span>
                        {r.sublabel && (
                          <span className="text-[10px]" style={{ color: '#7A7D85' }}>
                            {r.sublabel}
                          </span>
                        )}
                      </span>
                    </button>
                  ))}
                </div>
              )}
            </div>
          )}
        </div>
      </div>

      {/* Right section — Bell + Avatar, moved toward center (away from window edge) */}
      <div className="flex items-center gap-4" style={{ marginRight: '40px' }}>

        {/* Notifications */}
        <button className="relative p-1.5 text-text-secondary hover:text-gold transition-colors bg-transparent border-none cursor-pointer">
          <Bell size={17} />
        </button>

        {/* User Avatar + Dropdown */}
        <div className="relative" ref={menuRef}>
          <button
            onClick={() => setUserMenuOpen(!userMenuOpen)}
            className="flex items-center gap-2 bg-transparent border-none cursor-pointer p-0"
          >
            <div className="w-9 h-9 rounded-full border-2 border-gold bg-card flex items-center justify-center text-gold font-bold text-[12px] shadow-[0_0_8px_rgba(200,164,52,0.4)] overflow-hidden">
              {user?.avatar_data_url ? (
                <img src={user.avatar_data_url} alt={displayName} className="w-full h-full object-cover" />
              ) : (
                initials
              )}
            </div>
            <div className="flex flex-col text-left">
              <span className="text-[12px] text-text-primary font-medium leading-tight">{displayName}</span>
              <span className="text-[9px] text-text-secondary leading-tight">Administrator</span>
            </div>
            <ChevronDown size={12} className={`text-text-secondary transition-transform duration-200 ${userMenuOpen ? 'rotate-180' : ''}`} />
          </button>

          {userMenuOpen && (
            <div className="absolute right-0 top-full mt-2 w-48 bg-card border border-border rounded-xl overflow-hidden shadow-lg z-50">
              <div className="p-3 border-b border-border">
                <p className="text-[12px] text-text-primary font-medium">{displayName}</p>
                <p className="text-[10px] text-text-secondary">{user?.email || user?.username}</p>
              </div>
              <div className="py-1">
                <a href="#" className="flex items-center gap-2.5 px-3 py-2 text-[12px] text-text-secondary hover:text-text-primary hover:bg-page transition-colors no-underline">
                  <User size={14} />
                  <span>Profile</span>
                </a>
                <a href="#" className="flex items-center gap-2.5 px-3 py-2 text-[12px] text-text-secondary hover:text-text-primary hover:bg-page transition-colors no-underline">
                  <Palette size={14} />
                  <span>Appearance</span>
                </a>
                <a href="#" className="flex items-center gap-2.5 px-3 py-2 text-[12px] text-text-secondary hover:text-text-primary hover:bg-page transition-colors no-underline">
                  <Shield size={14} />
                  <span>Security</span>
                </a>
                <button
                  onClick={() => { setUserMenuOpen(false); navigate('/help') }}
                  className="flex w-full items-center gap-2.5 px-3 py-2 text-[12px] text-text-secondary hover:text-text-primary hover:bg-page transition-colors cursor-pointer border-none bg-transparent text-left"
                >
                  <HelpCircle size={14} />
                  <span>Help & Support</span>
                </button>
              </div>
              <div className="border-t border-border py-1">
                <button
                  onClick={logout}
                  className="flex w-full items-center gap-2.5 px-3 py-2 text-[12px] text-danger hover:bg-page transition-colors cursor-pointer border-none bg-transparent text-left"
                >
                  <LogOut size={14} />
                  <span>Sign Out</span>
                </button>
              </div>
            </div>
          )}
        </div>
      </div>
    </header>
  )
}