"use client"

import { useEffect, useRef, useState, useMemo } from "react"
import { PageHeader } from "@/components/page-header"
import { DataPageCard } from "@/components/data-page-card"
import {
  CommunitiesDataGrid,
  type CommunityRow,
  TYPE_LABELS,
  ACTION_LABELS,
} from "@/components/data-grids/communities-data-grid"
import { Frame, FramePanel } from "@/components/reui/frame"
import { KpiStatGrid } from "@/components/reui-kit/kpi-stat-grid"
import { OpsPanel } from "@/components/ops-panel"
import { Alert, AlertTitle, AlertDescription } from "@/components/reui/alert"
import { Button } from "@/components/ui/button"
import { Input } from "@/components/ui/input"
import {
  PlusIcon, SearchIcon, TagIcon, FilterIcon,
  CopyIcon, CheckIcon, TrashIcon, PencilIcon,
} from "lucide-react"
import { cn } from "@/lib/utils"
import { filters } from "@/lib/data"
import { useEvoCatalogView, EvoBgpCatalogStatus, EvoBgpCatalogUnavailable } from "@/components/settings/evobgp-catalog-status"
import { useEvoBGP } from "@/lib/evobgp-context"

// ─── types ────────────────────────────────────────────────────────────────────

type Community = CommunityRow
type CommType = CommunityRow["type"]

// ─── mock data ────────────────────────────────────────────────────────────────

const COMMUNITIES: Community[] = [
  {
    id: "c1", value: "65001:100", name: "youtube-bypass",
    description: "Пометка для трафика YouTube — маршрутизация через SPB/FRA exit nodes",
    type: "standard", filterIds: ["f1"], serverCount: 4, prefixCount: 842,
    action: "local-pref", actionValue: 200, enabled: true,
  },
  {
    id: "c2", value: "65001:200", name: "streaming-eu",
    description: "EU-стриминг (Netflix, Twitch) — выход через FRA/AMS",
    type: "standard", filterIds: ["f1", "f2"], serverCount: 3, prefixCount: 614,
    action: "local-pref", actionValue: 180, enabled: true,
  },
  {
    id: "c3", value: "65001:300", name: "cdn-bypass",
    description: "Обход CDN-провайдеров через прямые пиринговые IX-точки",
    type: "standard", filterIds: ["f3"], serverCount: 5, prefixCount: 4218,
    action: "local-pref", actionValue: 210, enabled: true,
  },
  {
    id: "c4", value: "65002:100", name: "cdn-secondary",
    description: "Резервный CDN-путь при деградации основного",
    type: "standard", filterIds: ["f3"], serverCount: 5, prefixCount: 1842,
    action: "metric", actionValue: 50, enabled: true,
  },
  {
    id: "c5", value: "65001:400", name: "office-direct",
    description: "Office 365 / Teams — прямой выход без туннелирования",
    type: "standard", filterIds: ["f5"], serverCount: 6, prefixCount: 882,
    action: "permit", enabled: true,
  },
  {
    id: "c6", value: "65001:500", name: "gaming-ll",
    description: "Low-latency gaming — приоритет по минимальному RTT (Discord, Steam)",
    type: "standard", filterIds: ["f6"], serverCount: 4, prefixCount: 1212,
    action: "local-pref", actionValue: 250, enabled: true,
  },
  {
    id: "c7", value: "65002:200", name: "gaming-ll-backup",
    description: "Резервный путь для gaming-low-latency",
    type: "standard", filterIds: ["f6"], serverCount: 4, prefixCount: 412,
    action: "metric", actionValue: 80, enabled: true,
  },
  {
    id: "c8", value: "65007:999", name: "school-block",
    description: "Блокировка соцсетей для школьного сегмента LAN",
    type: "standard", filterIds: ["f4"], serverCount: 2, prefixCount: 412,
    action: "deny", enabled: false,
  },
  {
    id: "c9", value: "no-export", name: "no-export",
    description: "Не объявлять маршрут за пределы AS (RFC 1997)",
    type: "no-export", filterIds: [], serverCount: 1, prefixCount: 0,
    action: "permit", enabled: true,
  },
  {
    id: "c10", value: "no-advertise", name: "no-advertise",
    description: "Не передавать маршрут ни одному BGP-пиру (RFC 1997)",
    type: "no-advertise", filterIds: [], serverCount: 1, prefixCount: 0,
    action: "permit", enabled: true,
  },
]

// ─── page ─────────────────────────────────────────────────────────────────────

export default function CommunitiesPage() {
  const { sourceKey } = useEvoBGP()
  return <CommunitiesContent key={sourceKey} />
}
function CommunitiesContent() {
  const { mode, snapshot, loading, known } = useEvoCatalogView()

  const [search, setSearch] = useState("")
  const [typeFilter, setTypeFilter] = useState<CommType | "all">("all")
  const [copied, setCopied] = useState<string | null>(null)
  const [copying, setCopying] = useState(false)
  const [copyError, setCopyError] = useState<string | null>(null)
  const copyRequest = useRef({ active: true, pending: false, revision: 0, timer: null as ReturnType<typeof setTimeout> | null })
  useEffect(() => {
    const state = copyRequest.current; state.active = true
    return () => { state.active = false; state.revision++; if (state.timer) clearTimeout(state.timer) }
  }, [])
  const [selectedId, setSelectedId] = useState<string | null>(null)

  const listData = useMemo((): Community[] => {
    if (mode === "mock") return COMMUNITIES
    if (loading && !snapshot) return []
    return snapshot?.communities ?? []
  }, [mode, loading, snapshot])

  const selected = known ? listData.find(row => row.id === selectedId) ?? null : null

  const filtered = useMemo(() => {
    const q = search.toLowerCase()
    return listData.filter(c => {
      const matchQ = !q || c.value.toLowerCase().includes(q) || c.name.toLowerCase().includes(q) || c.description.toLowerCase().includes(q)
      const matchT = typeFilter === "all" || c.type === typeFilter
      return matchQ && matchT
    })
  }, [search, typeFilter, listData])

  const handleCopy = async (value: string) => {
    const state = copyRequest.current
    if (!state.active || state.pending) return
    state.pending = true; const revision = ++state.revision
    if (state.timer) clearTimeout(state.timer)
    const current = () => state.active && state.revision === revision
    setCopying(true); setCopied(null); setCopyError(null)
    try {
      await navigator.clipboard.writeText(value)
      if (!current()) return
      setCopied(value)
      state.timer = setTimeout(() => { if (current()) setCopied(null) }, 1500)
    } catch {
      if (current()) setCopyError("Браузер не разрешил запись в буфер обмена. Повторите копирование или выделите значение вручную.")
    } finally {
      state.pending = false
      if (current()) setCopying(false)
    }
  }

  const filterName = (id: string) => filters.find(f => f.id === id)?.name ?? id

  return (
    <div className="flex flex-col h-full">
      <PageHeader
        crumbs={[{ label: "Данные" }, { label: "Communities" }]}
        actions={mode === "live" ? null : <Button size="sm">
            <PlusIcon className="size-4" />Добавить
          </Button>
        }
      />

      <div className="flex-1 overflow-y-auto p-6">
        <div className="flex flex-col gap-5">
          <EvoBgpCatalogStatus />
          {copyError && <Alert variant="warning"><AlertTitle>Community не скопировано</AlertTitle><AlertDescription>{copyError}</AlertDescription></Alert>}
          {copying && <p role="status" className="text-xs text-muted-foreground">Копирование community…</p>}
          {copied && <p role="status" className="text-xs text-muted-foreground">Community {copied} скопировано</p>}

          <KpiStatGrid
            aria-label="Сводка communities"
            items={[
              {
                id: "all",
                label: "Всего communities",
                value: known ? String(listData.length) : "—",
                icon: <TagIcon className="size-4" />,
                iconClassName: "text-muted-foreground",
              },
              {
                id: "enabled",
                label: "Активных",
                value: known ? String(listData.filter((c) => c.enabled).length) : "—",
                icon: <CheckIcon className="size-4" />,
                iconClassName: "text-success",
              },
              {
                id: "standard",
                label: "Стандартных",
                value: known ? String(listData.filter((c) => c.type === "standard").length) : "—",
                icon: <TagIcon className="size-4" />,
                iconClassName: "text-info",
              },
              {
                id: "filters",
                label: "Использует фильтры",
                value: mode === "mock" ? String(new Set(listData.flatMap((c) => c.filterIds)).size) : "—",
                icon: <FilterIcon className="size-4" />,
                iconClassName: "text-primary",
              },
            ]}
          />

          <div className="grid grid-cols-1 xl:grid-cols-[minmax(0,1fr)_320px] gap-5">
            {/* ── main table ── */}
            <div className="flex flex-col gap-3">
              {/* toolbar */}
              <div className="flex gap-2 flex-wrap">
                <div className="relative flex-1 min-w-[180px]">
                  <SearchIcon className="absolute left-2.5 top-2 size-4 text-muted-foreground" />
                  <Input className="pl-8 h-8 text-sm" placeholder="Поиск community…" value={search} onChange={e => setSearch(e.target.value)} />
                </div>
                <div className="flex flex-wrap gap-1">
                  {(["all", "standard", "no-export", "no-advertise", "custom"] as const).map(t => (
                    <Button key={t} size="sm" variant={typeFilter === t ? "default" : "outline"}
                      className="h-8 text-xs px-2.5" onClick={() => setTypeFilter(t)}>
                      {t === "all" ? "Все" : TYPE_LABELS[t] ?? t}
                    </Button>
                  ))}
                </div>
              </div>

              {/* list */}
              <DataPageCard>
                {known ? <CommunitiesDataGrid
                  communities={filtered}
                  selectedId={selected?.id}
                  copiedValue={copied}
                  copying={copying}
                  onSelect={row => setSelectedId(row.id)}
                  onCopy={handleCopy}
                /> : <EvoBgpCatalogUnavailable />}
              </DataPageCard>
            </div>

            {/* ── detail panel ── */}
            {selected ? (
              <OpsPanel
                className="h-fit sticky top-0"
                title={<span className="font-mono">{selected.value}</span>}
                description={selected.name}
                headerRight={
                    <div className="flex gap-1 shrink-0">
                      <Button size="sm" variant="ghost" aria-label="Изменить community" disabled className="size-7 p-0"><PencilIcon className="size-3.5" /></Button>
                      <Button size="sm" variant="ghost" aria-label="Удалить community" disabled className="size-7 p-0 text-destructive hover:text-destructive"><TrashIcon className="size-3.5" /></Button>
                    </div>
                }
                contentClassName="flex flex-col gap-4 text-sm px-5 pb-5"
              >
                  <div className="flex items-center gap-2">
                    <span className={cn(
                      "inline-flex items-center rounded-full px-2 py-0.5 text-[10px] font-medium",
                      selected.enabled
                        ? "bg-emerald-500/10 text-emerald-600"
                        : "bg-muted text-muted-foreground"
                    )}>
                      {selected.enabled ? "Активен" : "Выключен"}
                    </span>
                  </div>
                  <p className="text-xs text-muted-foreground">{selected.description}</p>

                  <div className="space-y-2">
                    {[
                      ["Тип",       TYPE_LABELS[selected.type]],
                      ["Действие",  `${ACTION_LABELS[selected.action]}${selected.actionValue !== undefined ? ` ${selected.actionValue}` : ""}`],
                      ["Маршрутов", selected.prefixCount?.toLocaleString("ru-RU") ?? "—"],
                      ["Серверов",  selected.serverCount.toLocaleString("ru-RU")],
                    ].map(([k, v]) => (
                      <div key={k} className="flex justify-between gap-2">
                        <span className="text-xs text-muted-foreground">{k}</span>
                        <span className="text-xs font-medium">{v}</span>
                      </div>
                    ))}
                  </div>

                  {selected.filterIds.length > 0 && (
                    <div>
                      <p className="text-xs text-muted-foreground mb-2 flex items-center gap-1.5">
                        <FilterIcon className="size-3" />Использующие фильтры
                      </p>
                      <div className="flex flex-wrap gap-1.5">
                        {selected.filterIds.map(fid => (
                          <span key={fid} className="text-[11px] bg-muted px-2 py-0.5 rounded font-mono">
                            {filterName(fid)}
                          </span>
                        ))}
                      </div>
                    </div>
                  )}

                  <div className="pt-2 border-t flex flex-col gap-2">
                    <Button size="sm" variant="outline" className="w-full justify-start gap-2" disabled={copying} onClick={() => { void handleCopy(selected.value) }}>
                      {copied === selected.value ? <CheckIcon className="size-3.5" /> : <CopyIcon className="size-3.5" />}
                      Скопировать значение
                    </Button>
                  </div>
              </OpsPanel>
            ) : (
              <Frame dense className="w-full h-fit">
                <FramePanel className="flex flex-col items-center justify-center py-12 gap-3 text-center">
                  <TagIcon className="size-8 text-muted-foreground/30" />
                  <p className="text-xs text-muted-foreground">Выберите community<br />для просмотра деталей</p>
                </FramePanel>
              </Frame>
            )}
          </div>
        </div>
      </div>
    </div>
  )
}