'use client'

import { useState, useCallback, useEffect, useRef } from 'react'
import dynamic from 'next/dynamic'
import Link from 'next/link'
import { usePathname } from 'next/navigation'
import { formatUpdatedAgo } from '@ciphera-net/ui'
import { CaretRight, SidebarSimple } from '@phosphor-icons/react'
import { SidebarProvider, useSidebar } from '@/lib/sidebar-context'
import { useRealtime } from '@/lib/swr/dashboard'
import { getSite } from '@/lib/api/sites'
import ContentHeader from './ContentHeader'

const PAGE_TITLES: Record<string, string> = {
  '': 'Dashboard',
  journeys: 'Journeys',
  funnels: 'Funnels',
  behavior: 'Behavior',
  search: 'Search',
  cdn: 'CDN',
  uptime: 'Uptime',
  pagespeed: 'PageSpeed',
  settings: 'Site Settings',
}

function usePageTitle() {
  const pathname = usePathname()
  // pathname is /sites/:id or /sites/:id/section/...
  const segment = pathname.replace(/^\/sites\/[^/]+\/?/, '').split('/')[0]
  return PAGE_TITLES[segment] ?? (segment ? segment.charAt(0).toUpperCase() + segment.slice(1) : 'Dashboard')
}

const HOME_PAGE_TITLES: Record<string, string> = {
  '': 'Your Sites',
  integrations: 'Integrations',
  pricing: 'Pricing',
}

function useHomePageTitle() {
  const pathname = usePathname()
  const segment = pathname.split('/').filter(Boolean)[0] ?? ''
  return HOME_PAGE_TITLES[segment] ?? (segment ? segment.charAt(0).toUpperCase() + segment.slice(1) : 'Your Sites')
}

// Load sidebar only on the client — prevents SSR flash
const Sidebar = dynamic(() => import('./Sidebar'), {
  ssr: false,
  loading: () => (
    <div
      className="hidden md:block shrink-0 bg-transparent overflow-hidden relative"
      style={{ width: 64 }}
    >
      <div className="absolute inset-0 bg-gradient-to-r from-transparent via-neutral-800/10 to-transparent animate-shimmer" />
    </div>
  ),
})

function GlassTopBar({ siteId }: { siteId: string | null }) {
  const { collapsed, toggle } = useSidebar()
  const { data: realtime } = useRealtime(siteId ?? '')
  const lastUpdatedRef = useRef<number | null>(null)
  const [, setTick] = useState(0)
  const [siteName, setSiteName] = useState<string | null>(null)

  useEffect(() => {
    if (siteId && realtime) lastUpdatedRef.current = Date.now()
  }, [siteId, realtime])

  useEffect(() => {
    if (lastUpdatedRef.current == null) return
    const timer = setInterval(() => setTick((t) => t + 1), 1000)
    return () => clearInterval(timer)
  }, [realtime])

  useEffect(() => {
    if (!siteId) { setSiteName(null); return }
    getSite(siteId).then((s) => setSiteName(s.name)).catch(() => {})
  }, [siteId])

  const dashboardTitle = usePageTitle()
  const homeTitle = useHomePageTitle()
  const pageTitle = siteId ? dashboardTitle : homeTitle

  return (
    <div className="hidden md:flex items-center justify-between shrink-0 px-3 pt-1.5 pb-1">
      {/* Left: collapse toggle + breadcrumbs */}
      <div className="flex items-center gap-1.5">
        <button
          onClick={toggle}
          className="w-9 h-9 flex items-center justify-center text-neutral-400 hover:text-white rounded-lg hover:bg-white/[0.06] transition-colors"
          aria-label={collapsed ? 'Expand sidebar' : 'Collapse sidebar'}
        >
          <SidebarSimple className="w-[18px] h-[18px]" weight={collapsed ? 'regular' : 'fill'} />
        </button>
        {siteId && siteName ? (
          <nav className="flex items-center gap-1 text-sm font-medium">
            <Link href="/" className="text-neutral-500 hover:text-neutral-300 transition-colors">Your Sites</Link>
            <CaretRight className="w-3 h-3 text-neutral-600" />
            <Link href={`/sites/${siteId}`} className="text-neutral-500 hover:text-neutral-300 transition-colors truncate max-w-[160px]">{siteName}</Link>
            <CaretRight className="w-3 h-3 text-neutral-600" />
            <span className="text-neutral-400">{pageTitle}</span>
          </nav>
        ) : (
          <span className="text-sm text-neutral-400 font-medium">{pageTitle}</span>
        )}
      </div>

      {/* Realtime indicator */}
      {siteId && lastUpdatedRef.current != null && (
        <div className="flex items-center gap-1.5 text-xs text-neutral-500">
          <span className="relative flex h-1.5 w-1.5">
            <span className="animate-ping absolute inline-flex h-full w-full rounded-full bg-green-500 opacity-75" />
            <span className="relative inline-flex rounded-full h-1.5 w-1.5 bg-green-500" />
          </span>
          Live · {formatUpdatedAgo(lastUpdatedRef.current)}
        </div>
      )}
    </div>
  )
}

export default function DashboardShell({
  siteId,
  children,
}: {
  siteId: string | null
  children: React.ReactNode
}) {
  const [mobileOpen, setMobileOpen] = useState(false)
  const closeMobile = useCallback(() => setMobileOpen(false), [])
  const openMobile = useCallback(() => setMobileOpen(true), [])

  return (
    <SidebarProvider>
      <div className="flex h-screen overflow-hidden bg-neutral-900/65 backdrop-blur-3xl backdrop-saturate-150 supports-[backdrop-filter]:bg-neutral-900/60">
        <Sidebar
          siteId={siteId}
          mobileOpen={mobileOpen}
          onMobileClose={closeMobile}
          onMobileOpen={openMobile}
        />
        <div className="flex-1 flex flex-col min-w-0">
          {/* Glass top bar — above content only, collapse icon reaches back into sidebar column */}
          <GlassTopBar siteId={siteId} />
          {/* Content panel */}
          <div className="flex-1 flex flex-col min-w-0 mr-2 mb-2 rounded-2xl bg-neutral-950 border border-neutral-800/60 overflow-hidden">
            <ContentHeader onMobileMenuOpen={openMobile} />
            <main className="flex-1 overflow-y-auto pt-4">
              {children}
            </main>
          </div>
        </div>
      </div>
    </SidebarProvider>
  )
}