'use client'

import Link from 'next/link'
import { usePathname, useRouter } from 'next/navigation'
import { createBrowserClient } from '@supabase/ssr'
import { NotificationBell } from '@/components/notifications/bell'

interface NavItem {
  label: string
  href: string
  icon: React.ReactNode
}

interface SidebarProps {
  role: string
  userName: string
  userEmail: string
}

const IconGrid = () => (
  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 6h16M4 12h16M4 18h7" />
  </svg>
)
const IconList = () => (
  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2" />
  </svg>
)
const IconCheck = () => (
  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z" />
  </svg>
)
const IconChart = () => (
  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 19v-6a2 2 0 00-2-2H5a2 2 0 00-2 2v6a2 2 0 002 2h2a2 2 0 002-2zm0 0V9a2 2 0 012-2h2a2 2 0 012 2v10m-6 0a2 2 0 002 2h2a2 2 0 002-2m0 0V5a2 2 0 012-2h2a2 2 0 012 2v14a2 2 0 01-2 2h-2a2 2 0 01-2-2z" />
  </svg>
)
const IconSettings = () => (
  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M10.325 4.317c.426-1.756 2.924-1.756 3.35 0a1.724 1.724 0 002.573 1.066c1.543-.94 3.31.826 2.37 2.37a1.724 1.724 0 001.065 2.572c1.756.426 1.756 2.924 0 3.35a1.724 1.724 0 00-1.066 2.573c.94 1.543-.826 3.31-2.37 2.37a1.724 1.724 0 00-2.572 1.065c-.426 1.756-2.924 1.756-3.35 0a1.724 1.724 0 00-2.573-1.066c-1.543.94-3.31-.826-2.37-2.37a1.724 1.724 0 00-1.065-2.572c-1.756-.426-1.756-2.924 0-3.35a1.724 1.724 0 001.066-2.573c-.94-1.543.826-3.31 2.37-2.37.996.608 2.296.07 2.572-1.065z" />
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15 12a3 3 0 11-6 0 3 3 0 016 0z" />
  </svg>
)
const IconUsers = () => (
  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z" />
  </svg>
)
const IconPlus = () => (
  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 4v16m8-8H4" />
  </svg>
)
const IconLogout = () => (
  <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17 16l4-4m0 0l-4-4m4 4H7m6 4v1a3 3 0 01-3 3H6a3 3 0 01-3-3V7a3 3 0 013-3h4a3 3 0 013 3v1" />
  </svg>
)

const NAV_ITEMS: Record<string, NavItem[]> = {
  reporter: [
    { label: 'My Reports', href: '/reporter', icon: <IconList /> },
    { label: 'New Incident', href: '/report', icon: <IconPlus /> },
  ],
  supervisor: [
    { label: 'Overview', href: '/supervisor', icon: <IconGrid /> },
    { label: 'Incidents', href: '/supervisor/incidents', icon: <IconList /> },
  ],
  hse: [
    { label: 'Dashboard', href: '/hse/dashboard', icon: <IconChart /> },
    { label: 'Incidents', href: '/hse/incidents', icon: <IconList /> },
    { label: 'CAPA', href: '/hse/capa', icon: <IconCheck /> },
    { label: 'Settings', href: '/hse/settings', icon: <IconSettings /> },
  ],
  management: [
    { label: 'Dashboard', href: '/management', icon: <IconChart /> },
  ],
  capa_owner: [
    { label: 'My CAPAs', href: '/capa-owner', icon: <IconCheck /> },
  ],
  admin: [
    { label: 'Admin', href: '/admin', icon: <IconUsers /> },
    { label: 'Dashboard', href: '/hse/dashboard', icon: <IconChart /> },
    { label: 'Incidents', href: '/hse/incidents', icon: <IconList /> },
    { label: 'CAPA', href: '/hse/capa', icon: <IconCheck /> },
    { label: 'Management', href: '/management', icon: <IconGrid /> },
  ],
}

function initials(name: string): string {
  return name
    .split(' ')
    .map(w => w[0] ?? '')
    .join('')
    .toUpperCase()
    .slice(0, 2)
}

function useNavItems(role: string): NavItem[] {
  return NAV_ITEMS[role] ?? NAV_ITEMS.reporter
}

function NavLink({ item, pathname }: { item: NavItem; pathname: string }) {
  // Exact match for root-level single-page roles, prefix match otherwise
  const exactRoots = ['/reporter', '/supervisor', '/management', '/capa-owner', '/admin', '/report']
  const isActive = exactRoots.includes(item.href)
    ? pathname === item.href
    : pathname.startsWith(item.href)

  return (
    <Link
      href={item.href}
      className={`flex items-center gap-3 px-3 py-2 rounded-lg text-sm font-medium transition-colors ${
        isActive
          ? 'bg-blue-50 text-blue-700'
          : 'text-gray-600 hover:bg-gray-100 hover:text-gray-900'
      }`}
    >
      <span className={isActive ? 'text-blue-600' : 'text-gray-400'}>{item.icon}</span>
      {item.label}
    </Link>
  )
}

export function Sidebar({ role, userName, userEmail }: SidebarProps) {
  const pathname = usePathname()
  const router = useRouter()
  const items = useNavItems(role)
  const mobileItems = items.slice(0, 4)

  const logout = async () => {
    const supabase = createBrowserClient(
      process.env.NEXT_PUBLIC_SUPABASE_URL!,
      process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!,
    )
    await supabase.auth.signOut()
    router.push('/login')
  }

  const displayName = userName || userEmail || 'User'
  const roleLabel = role.replace(/_/g, ' ').replace(/\b\w/g, c => c.toUpperCase())

  return (
    <>
      {/* Desktop sidebar */}
      <aside className="hidden md:flex fixed left-0 top-0 h-full w-60 bg-white border-r border-gray-200 flex-col z-40">
        {/* Header */}
        <div className="flex items-center justify-between px-4 py-4 border-b border-gray-100">
          <span className="text-base font-bold text-gray-900 tracking-tight">IMS</span>
          <NotificationBell />
        </div>

        {/* Nav */}
        <nav className="flex-1 overflow-y-auto px-3 py-3 space-y-1">
          {items.map(item => (
            <NavLink key={item.href} item={item} pathname={pathname} />
          ))}
        </nav>

        {/* User + logout */}
        <div className="border-t border-gray-100 px-3 py-3">
          <div className="flex items-center gap-2 px-2 py-2 mb-1">
            <div className="w-8 h-8 rounded-full bg-blue-600 flex items-center justify-center text-white text-xs font-bold flex-shrink-0">
              {initials(displayName)}
            </div>
            <div className="min-w-0">
              <p className="text-sm font-medium text-gray-900 truncate">{displayName}</p>
              <p className="text-xs text-gray-500 truncate">{roleLabel}</p>
            </div>
          </div>
          <button
            onClick={logout}
            className="flex items-center gap-2 w-full px-3 py-2 text-sm text-gray-600 hover:bg-gray-100 hover:text-gray-900 rounded-lg transition-colors"
          >
            <IconLogout />
            Logout
          </button>
        </div>
      </aside>

      {/* Mobile bottom tab bar */}
      <nav className="md:hidden fixed bottom-0 left-0 right-0 bg-white border-t border-gray-200 flex z-40 safe-area-pb">
        {mobileItems.map(item => {
          const exactRoots = ['/reporter', '/supervisor', '/management', '/capa-owner', '/admin', '/report']
          const isActive = exactRoots.includes(item.href)
            ? pathname === item.href
            : pathname.startsWith(item.href)
          return (
            <Link
              key={item.href}
              href={item.href}
              className={`flex-1 flex flex-col items-center gap-1 py-2 text-[10px] font-medium transition-colors ${
                isActive ? 'text-blue-600' : 'text-gray-400'
              }`}
            >
              {item.icon}
              <span className="leading-none">{item.label}</span>
            </Link>
          )
        })}
        {/* Mobile logout in "More" slot if room */}
        {items.length <= 4 && (
          <button
            onClick={logout}
            className="flex-1 flex flex-col items-center gap-1 py-2 text-[10px] font-medium text-gray-400"
          >
            <IconLogout />
            <span className="leading-none">Logout</span>
          </button>
        )}
      </nav>
    </>
  )
}