"use client";

/**
 * Live — the default landing for every authenticated user (UI_REDESIGN.md
 * §3, §5.1), now the live ops wall (design-canvas/live-ops-wall-mockup.html):
 * Region → Incident → Camera drill-down, worst-first incident rail (MapView),
 * KPIs, transcript ticker, scrubber with incident bands, auto-tour and deep
 * links (#inc=…&cam=…&tour). Every MapView layer stays — nodes, incidents,
 * paths, ADS-B, AIS, cameras, viewsheds, traffic events, NEXRAD.
 */
import { useCallback, useEffect, useMemo, useState } from "react";
import dynamic from "next/dynamic";
import { useNodes } from "@/lib/useNodes";
import { useActiveCalls, useCalls } from "@/lib/useCalls";
import { useActiveIncidents } from "@/lib/useIncidents";
import { useAircraft } from "@/lib/useAircraft";
import { useVessels } from "@/lib/useVessels";
import { useCamerasInBbox } from "@/lib/useCameras";
import { c2api } from "@/lib/c2api";
import { severityRank } from "@/lib/severity";
import type { Camera, Ny511Response } from "@/lib/types";
import {
  NEAR_CAMERA_KM, bboxAround, groupCallsByIncident, incidentPoints, km, nearestCameras, onAirIncidentIds,
  parseWallHash, wallHash, worstFirst, type LatLon, type NearCamera, type WallLink,
} from "@/lib/liveWall";
import { TimeScrubber } from "@/components/TimeScrubber";
import { TranscriptTicker } from "@/components/live/TranscriptTicker";
import { CameraDrill } from "@/components/live/CameraDrill";
import { IncidentPanel, RegionPanel } from "@/components/live/WallPanels";

const MapView = dynamic(() => import("@/components/MapView"), { ssr: false });

const TOUR_MS = 20_000;
const PIN_KEY = "drb.wall.pinnedCameras";
const MAX_PINNED = 6;
const EVENTS_POLL_MS = 2 * 60 * 1000;

function timeAgo(date: Date): string {
  const s = Math.floor((Date.now() - date.getTime()) / 1000);
  if (s < 60) return `${s}s ago`;
  if (s < 3600) return `${Math.floor(s / 60)}m ago`;
  return `${Math.floor(s / 3600)}h ago`;
}

/** Per-viewer convenience only; the wall works without it. */
function loadPinned(): Camera[] {
  try {
    const raw = window.localStorage.getItem(PIN_KEY);
    const v = raw ? JSON.parse(raw) : [];
    return Array.isArray(v) ? v.filter((c) => c && typeof c.id === "string").slice(0, MAX_PINNED) : [];
  } catch {
    return [];
  }
}
function savePinned(cams: Camera[]) {
  try { window.localStorage.setItem(PIN_KEY, JSON.stringify(cams)); } catch { /* storage blocked */ }
}

/** 511NY road events around the region (situational context + KPI). */
function useRegionEvents(box: ReturnType<typeof bboxAround>) {
  const [data, setData] = useState<Ny511Response>({});
  const key = box ? [box.south, box.west, box.north, box.east].map((n) => n.toFixed(2)).join(",") : "";
  useEffect(() => {
    if (!box) return;
    const b = box;
    let cancelled = false;
    const load = () => {
      if (document.hidden) return;
      c2api.get511(b, "events").then((r) => { if (!cancelled) setData(r); }).catch((e) => console.error("region events:", e));
    };
    load();
    const id = setInterval(load, EVENTS_POLL_MS);
    return () => { cancelled = true; clearInterval(id); };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [key]);
  return data;
}

function Kpi({ value, label }: { value: string | number; label: string }) {
  return (
    <span className="inline-flex items-baseline gap-1 text-xs text-ink-muted whitespace-nowrap">
      <b className="text-ink font-semibold tabular-nums">{value}</b>{label}
    </span>
  );
}

export function LiveView() {
  const { nodes, loading: nodesLoading } = useNodes();
  const activeCalls = useActiveCalls();
  const activeIncidents = useActiveIncidents();
  // Wide-ish recent window: feeds incident paths, the call spine, the ticker
  // and the scrubber's density bars. Real recent calls, not a fixture.
  const { calls: recentCalls, loading: callsLoading } = useCalls(500);
  const { aircraft } = useAircraft();
  const { vessels } = useVessels();
  const [lastUpdated, setLastUpdated] = useState<Date | null>(null);
  const [clock, setClock] = useState<string>("");

  useEffect(() => {
    if (!nodesLoading) setLastUpdated(new Date());
  }, [nodes, activeCalls, activeIncidents, nodesLoading]);
  useEffect(() => {
    const tick = () => setClock(new Date().toLocaleTimeString([], { hour12: false }));
    tick();
    const id = setInterval(tick, 1000);
    return () => clearInterval(id);
  }, []);

  // ── Wall state, mirrored in the URL hash ──────────────────────────────────
  const [link, setLinkState] = useState<WallLink>({ inc: null, cam: null, tour: false });
  useEffect(() => {
    const read = () => setLinkState(parseWallHash(window.location.hash));
    read();
    window.addEventListener("hashchange", read);
    return () => window.removeEventListener("hashchange", read);
  }, []);
  const setLink = useCallback((next: WallLink) => {
    setLinkState(next);
    const h = wallHash(next);
    window.history.replaceState(null, "", h || window.location.pathname + window.location.search);
  }, []);

  const [pinned, setPinned] = useState<Camera[]>([]);
  useEffect(() => { setPinned(loadPinned()); }, []);
  const pinnedIds = useMemo(() => new Set(pinned.map((c) => c.id)), [pinned]);
  const togglePin = useCallback((cam: Camera) => {
    setPinned((prev) => {
      const next = prev.some((c) => c.id === cam.id) ? prev.filter((c) => c.id !== cam.id) : [...prev, cam].slice(-MAX_PINNED);
      savePinned(next);
      return next;
    });
  }, []);

  // ── Geography ─────────────────────────────────────────────────────────────
  const callsByIncident = useMemo(() => groupCallsByIncident(recentCalls), [recentCalls]);
  const sorted = useMemo(() => worstFirst(activeIncidents), [activeIncidents]);
  const pointsById = useMemo(() => {
    const m = new Map<string, LatLon[]>();
    for (const inc of activeIncidents) m.set(inc.incident_id, incidentPoints(inc, callsByIncident.get(inc.incident_id)));
    return m;
  }, [activeIncidents, callsByIncident]);
  const regionBox = useMemo(() => {
    const pts = Array.from(pointsById.values()).flat();
    return bboxAround(pts.length ? pts : nodes.map((n) => [n.lat, n.lon] as LatLon), NEAR_CAMERA_KM + 0.5);
  }, [pointsById, nodes]);
  const { data: cams, loaded: camsLoaded } = useCamerasInBbox(regionBox);
  const feeds = useMemo(() => new Map(cams.providers.map((p) => [p.id, p])), [cams.providers]);
  const nearById = useMemo(() => {
    const m = new Map<string, NearCamera[]>();
    pointsById.forEach((pts, id) => m.set(id, nearestCameras(pts, cams.cameras)));
    return m;
  }, [pointsById, cams.cameras]);
  const camCountByIncident = useMemo(() => new Map(Array.from(nearById.entries()).map(([id, n]) => [id, n.length])), [nearById]);
  const events = useRegionEvents(regionBox);
  const onAir = useMemo(() => onAirIncidentIds(activeIncidents, activeCalls), [activeIncidents, activeCalls]);

  const selected = link.inc ? activeIncidents.find((i) => i.incident_id === link.inc) ?? null : null;
  const selectedPoints = selected ? pointsById.get(selected.incident_id) ?? [] : [];
  const near = selected ? nearById.get(selected.incident_id) ?? [] : [];
  const drillCam: Camera | null = link.cam
    ? cams.cameras.find((c) => c.id === link.cam) ?? pinned.find((c) => c.id === link.cam) ?? null
    : null;

  // Region wall: pinned first, then the nearest camera to each major/moderate incident.
  const wallCameras = useMemo(() => {
    const out: { cam: Camera; km?: number }[] = pinned.map((cam) => ({ cam }));
    for (const inc of sorted) {
      if (severityRank(inc.severity) < 2) continue;
      const first = nearById.get(inc.incident_id)?.[0];
      if (first && !out.some((o) => o.cam.id === first.cam.id)) out.push({ cam: first.cam, km: first.km });
    }
    return out.slice(0, 6);
  }, [pinned, sorted, nearById]);

  // ── Navigation ────────────────────────────────────────────────────────────
  const selectIncident = useCallback((id: string) => setLink({ inc: id, cam: null, tour: false }), [setLink]);
  const openCamera = useCallback((c: Camera) => setLink({ ...link, cam: c.id, tour: false }), [link, setLink]);
  const stepUp = useCallback(() => {
    if (link.cam) setLink({ ...link, cam: null, tour: false });
    else if (link.inc) setLink({ inc: null, cam: null, tour: false });
    else if (link.tour) setLink({ ...link, tour: false });
  }, [link, setLink]);
  useEffect(() => {
    const onKey = (e: KeyboardEvent) => { if (e.key === "Escape") stepUp(); };
    window.addEventListener("keydown", onKey);
    return () => window.removeEventListener("keydown", onKey);
  }, [stepUp]);

  // ── Auto-tour: worst-first through major/moderate (else all plotted) ──────
  const tourList = useMemo(() => {
    const plotted = sorted.filter((i) => (pointsById.get(i.incident_id) ?? []).length);
    const serious = plotted.filter((i) => severityRank(i.severity) >= 2);
    return (serious.length ? serious : plotted).map((i) => i.incident_id);
  }, [sorted, pointsById]);
  const [tourStart, setTourStart] = useState(0);
  const [tourNow, setTourNow] = useState(0);
  useEffect(() => {
    if (!link.tour || !tourList.length) return;
    const next = () => {
      setLinkState((cur) => {
        const i = cur.inc ? tourList.indexOf(cur.inc) : -1;
        const nxt: WallLink = { inc: tourList[(i + 1) % tourList.length], cam: null, tour: true };
        window.history.replaceState(null, "", wallHash(nxt));
        return nxt;
      });
      setTourStart(Date.now());
    };
    if (!link.inc || !tourList.includes(link.inc)) next();
    else setTourStart(Date.now());
    const id = setInterval(next, TOUR_MS);
    const prog = setInterval(() => setTourNow(Date.now()), 500);
    return () => { clearInterval(id); clearInterval(prog); };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [link.tour, tourList.join(",")]);
  const tourPct = link.tour && tourStart ? Math.min(100, ((tourNow - tourStart) / TOUR_MS) * 100) : 0;

  // ── KPIs ──────────────────────────────────────────────────────────────────
  const count = (sev: string) => activeIncidents.filter((i) => i.severity === sev).length;
  const nodesUp = nodes.filter((n) => n.status !== "offline").length;
  const eventsOff = !!events.events_status?.disabled;

  const configuredButQuiet = !nodesLoading && nodes.length > 0 && activeIncidents.length === 0;
  const mostRecentSeen = configuredButQuiet
    ? nodes.map((n) => n.last_seen).filter((s): s is string => !!s).sort().at(-1)
    : null;

  const crumb = (label: string, active: boolean, enabled: boolean, onClick: () => void) => (
    <button type="button" disabled={!enabled} onClick={onClick} aria-current={active ? "true" : undefined}
      className={`px-1.5 py-0.5 rounded ${active ? "text-ink font-semibold" : enabled ? "text-ink-2 hover:text-ink" : "text-ink-muted"}`}>
      {label}
    </button>
  );

  return (
    <div className="flex flex-col h-full">
      {/* ── Wall bar: drill crumbs · KPIs · auto-tour · clock ── */}
      <div className="shrink-0 flex flex-wrap items-center gap-x-4 gap-y-1 px-3 py-1.5 border-b border-line bg-surface/95 text-xs">
        <nav aria-label="Drill level" className="flex items-center gap-0.5">
          {crumb("Region", !link.inc, true, () => setLink({ inc: null, cam: null, tour: false }))}
          <span className="text-ink-muted">›</span>
          {crumb(selected?.title ? `Incident: ${selected.title.slice(0, 32)}` : "Incident", !!link.inc && !link.cam, !!link.inc,
            () => setLink({ ...link, cam: null, tour: false }))}
          <span className="text-ink-muted">›</span>
          {crumb("Camera", !!link.cam, !!link.cam, () => undefined)}
        </nav>
        <div className="hidden md:flex items-center gap-3 flex-wrap">
          <Kpi value={count("major")} label="major" />
          <Kpi value={count("moderate")} label="moderate" />
          <Kpi value={activeIncidents.length} label="active" />
          <Kpi value={`${nodesUp}/${nodes.length}`} label="nodes" />
          <Kpi value={cams.cameras.length} label="cams" />
          <Kpi value={aircraft.length} label="aircraft" />
          <Kpi value={vessels.length} label="vessels" />
          <Kpi value={eventsOff ? "—" : events.events?.length ?? 0} label="road events" />
        </div>
        <div className="ml-auto flex items-center gap-3">
          <button type="button" aria-pressed={link.tour} onClick={() => setLink({ ...link, cam: null, tour: !link.tour })}
            title="Wall mode: cycle through active incidents, worst first"
            className={`px-2 py-0.5 rounded border ${link.tour ? "bg-accent text-white border-accent" : "border-line text-ink-2 hover:text-ink"}`}>
            Auto-tour
          </button>
          {link.tour && (
            <span className="w-20 h-1 bg-raised rounded overflow-hidden" aria-hidden="true">
              <span className="block h-full bg-accent" style={{ width: `${tourPct}%` }} />
            </span>
          )}
          <span className="font-mono text-ink-2 tabular-nums">{clock}</span>
        </div>
      </div>

      <div className="flex-1 min-h-0 flex flex-col lg:flex-row">
        <div className="relative h-[55vh] lg:h-auto lg:flex-1 min-w-0 shrink-0">
          {nodesLoading || callsLoading ? (
            <div className="w-full h-full flex items-center justify-center text-ink-muted text-sm">Loading map…</div>
          ) : (
            <MapView
              nodes={nodes}
              activeCalls={activeCalls}
              incidents={activeIncidents}
              calls={recentCalls}
              lastUpdated={lastUpdated}
              selectedIncidentId={selected?.incident_id ?? null}
              onSelectIncident={selectIncident}
              nearCameras={near}
              onOpenCamera={openCamera}
              onAir={onAir}
              camCountByIncident={camCountByIncident}
            />
          )}

          {/* Configured-and-quiet — distinct from "no nodes at all" (chunk 10's
              Activation screen handles the zero-node case). */}
          {configuredButQuiet && (
            <div className="absolute top-12 left-1/2 -translate-x-1/2 z-[1001] pointer-events-none">
              <span className="bg-surface/90 border border-line rounded-full px-3 py-1 text-xs text-ink-2 whitespace-nowrap">
                ● Listening{mostRecentSeen ? ` — last check-in ${timeAgo(new Date(mostRecentSeen))}` : ""}
              </span>
            </div>
          )}
        </div>

        <aside className="lg:w-[360px] lg:shrink-0 flex-1 lg:flex-none min-h-0 overflow-y-auto border-t lg:border-t-0 lg:border-l border-line bg-surface"
          aria-live="polite" aria-label={selected ? "Incident detail" : "Region overview"}>
          {selected ? (
            <IncidentPanel
              inc={selected}
              calls={callsByIncident.get(selected.incident_id) ?? []}
              points={selectedPoints}
              near={near}
              feeds={feeds}
              servingCount={camsLoaded ? cams.serving_count : 1}
              onAir={onAir.has(selected.incident_id)}
              aircraft={aircraft}
              vessels={vessels}
              events={events.events ?? []}
              eventsCredit={{ credit: events.credit, fetched_at: events.events_status?.fetched_at ?? null }}
              onOpenCamera={openCamera}
            />
          ) : (
            <RegionPanel
              incidents={activeIncidents}
              calls={recentCalls}
              onAirCount={onAir.size}
              nodes={nodes}
              wallCameras={wallCameras}
              feeds={feeds}
              servingCount={camsLoaded ? cams.serving_count : 1}
              aircraftCount={aircraft.length}
              vesselCount={vessels.length}
              events={events.events ?? []}
              eventsOff={eventsOff}
              pinnedIds={pinnedIds}
              onOpenCamera={openCamera}
            />
          )}
        </aside>
      </div>

      <TranscriptTicker calls={recentCalls} onSelectIncident={selectIncident} />
      <TimeScrubber calls={recentCalls} incidents={activeIncidents} selectedIncidentId={selected?.incident_id ?? null} onSelectIncident={selectIncident} />

      {drillCam && (
        <CameraDrill
          camera={drillCam}
          feed={feeds.get(drillCam.provider)}
          distanceKm={selectedPoints.length ? Math.min(...selectedPoints.map((p) => km(p, [drillCam.lat, drillCam.lon]))) : null}
          incidentTitle={selected?.title}
          pinned={pinnedIds.has(drillCam.id)}
          onTogglePin={() => togglePin(drillCam)}
          onClose={() => setLink({ ...link, cam: null })}
        />
      )}
    </div>
  );
}