import React, { useEffect, useMemo, useRef, useState } from 'react';

import { ipcChannels } from '../../shared/ipc/contracts';
import type { SessionState } from '../../shared/ipc/contracts';
import type { GraphNodeId, Scene, SceneId } from '../../shared/types';
import { getDndApi } from '../shared/dndApi';
import { PixiEffectsOverlay } from '../shared/effects/PxiEffectsOverlay';
import { useEffectsState } from '../shared/effects/useEffectsState';
import { Button } from '../shared/ui/controls';
import { Surface } from '../shared/ui/Surface';

import styles from './ControlApp.module.css';
import { ControlScenePreview } from './ControlScenePreview';

function formatTime(sec: number): string {
  if (!Number.isFinite(sec) || sec < 0) return '0:00';
  const s = Math.floor(sec);
  const m = Math.floor(s / 60);
  const r = s % 60;
  return `${String(m)}:${String(r).padStart(2, '0')}`;
}

export function ControlApp() {
  const api = getDndApi();
  const [fxState, fx] = useEffectsState();
  const [session, setSession] = useState<SessionState | null>(null);
  const historyRef = useRef<GraphNodeId[]>([]);
  const suppressNextHistoryPushRef = useRef(false);
  const [history, setHistory] = useState<GraphNodeId[]>([]);
  const audioElsRef = useRef<Map<string, HTMLAudioElement>>(new Map());
  const audioMetaRef = useRef<Map<string, { lastPlayError: string | null }>>(new Map());
  const [audioStateTick, setAudioStateTick] = useState(0);
  const audioLoadRunRef = useRef(0);
  const previewHostRef = useRef<HTMLDivElement | null>(null);
  const previewVideoRef = useRef<HTMLVideoElement | null>(null);
  const brushRef = useRef<{
    tool: 'fog' | 'fire' | 'rain' | 'lightning' | 'freeze' | 'eraser';
    startN?: { x: number; y: number };
    points?: { x: number; y: number; tMs: number }[];
  } | null>(null);
  const [draftFxTick, setDraftFxTick] = useState(0);
  const [cursorN, setCursorN] = useState<{ x: number; y: number } | null>(null);
  const [previewSize, setPreviewSize] = useState<{ w: number; h: number }>({ w: 1, h: 1 });
  const [previewContentRect, setPreviewContentRect] = useState<{
    x: number;
    y: number;
    w: number;
    h: number;
  } | null>(null);

  useEffect(() => {
    void api.invoke(ipcChannels.project.get, {}).then((res) => {
      const next: SessionState = {
        project: res.project,
        currentSceneId: res.project?.currentSceneId ?? null,
      };
      setSession(next);
      historyRef.current = next.project?.currentGraphNodeId ? [next.project.currentGraphNodeId] : [];
      setHistory(historyRef.current);
    });
    return api.on(ipcChannels.session.stateChanged, ({ state }) => {
      setSession(state);
      const cur = state.project?.currentGraphNodeId ?? null;
      if (!cur) return;
      const arr = historyRef.current;
      if (suppressNextHistoryPushRef.current) {
        suppressNextHistoryPushRef.current = false;
        setHistory(arr);
        return;
      }
      // Если мы перемотались на уже существующий шаг, не дублируем его в истории.
      if (arr.includes(cur)) {
        setHistory(arr);
        return;
      }
      if (arr[arr.length - 1] !== cur) {
        historyRef.current = [...arr, cur];
        setHistory(historyRef.current);
      }
    });
  }, [api]);

  const project = session?.project ?? null;
  const currentGraphNodeId = project?.currentGraphNodeId ?? null;
  const currentScene =
    project && session?.currentSceneId ? project.scenes[session.currentSceneId] : undefined;
  const isVideoPreviewScene = currentScene?.previewAssetType === 'video';
  const sceneAudioRefs = useMemo(() => currentScene?.media.audios ?? [], [currentScene]);

  const sceneAudios = useMemo(() => {
    if (!project) return [];
    return sceneAudioRefs
      .map((r) => {
        const a = project.assets[r.assetId];
        return a?.type === 'audio' ? { ref: r, asset: a } : null;
      })
      .filter((x): x is { ref: (typeof sceneAudioRefs)[number]; asset: NonNullable<typeof x>['asset'] } =>
        Boolean(x),
      );
  }, [project, sceneAudioRefs]);

  useEffect(() => {
    audioLoadRunRef.current += 1;
    const runId = audioLoadRunRef.current;
    // Cleanup old audios on scene change.
    const els = audioElsRef.current;
    for (const el of els.values()) {
      try {
        el.pause();
        el.currentTime = 0;
      } catch {
        // ignore
      }
    }
    els.clear();
    audioMetaRef.current.clear();
    setAudioStateTick((x) => x + 1);

    if (!project || !currentScene) return;
    void (async () => {
      const loaded: { ref: (typeof sceneAudioRefs)[number]; el: HTMLAudioElement }[] = [];
      for (const item of sceneAudioRefs) {
        const r = await api.invoke(ipcChannels.project.assetFileUrl, { assetId: item.assetId });
        if (audioLoadRunRef.current !== runId) return;
        if (!r.url) continue;
        const el = new Audio(r.url);
        el.loop = item.loop;
        el.preload = 'auto';
        audioMetaRef.current.set(item.assetId, { lastPlayError: null });
        el.addEventListener('play', () => setAudioStateTick((x) => x + 1));
        el.addEventListener('pause', () => setAudioStateTick((x) => x + 1));
        el.addEventListener('ended', () => setAudioStateTick((x) => x + 1));
        el.addEventListener('canplay', () => setAudioStateTick((x) => x + 1));
        el.addEventListener('error', () => setAudioStateTick((x) => x + 1));
        loaded.push({ ref: item, el });
        audioElsRef.current.set(item.assetId, el);
      }
      setAudioStateTick((x) => x + 1);
      for (const { ref, el } of loaded) {
        if (audioLoadRunRef.current !== runId) {
          try {
            el.pause();
            el.currentTime = 0;
          } catch {
            // ignore
          }
          continue;
        }
        if (!ref.autoplay) continue;
        try {
          await el.play();
        } catch {
          const m = audioMetaRef.current.get(ref.assetId) ?? { lastPlayError: null };
          audioMetaRef.current.set(ref.assetId, {
            ...m,
            lastPlayError:
              'Автозапуск заблокирован (нужно действие пользователя) или ошибка воспроизведения.',
          });
          setAudioStateTick((x) => x + 1);
        }
      }
    })();
  }, [api, currentScene, project, sceneAudioRefs]);

  const anyPlaying = useMemo(() => {
    for (const el of audioElsRef.current.values()) {
      if (!el.paused) return true;
    }
    return false;
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [audioStateTick]);

  useEffect(() => {
    if (!anyPlaying) return;
    let raf = 0;
    const tick = () => {
      setAudioStateTick((x) => x + 1);
      raf = window.requestAnimationFrame(tick);
    };
    raf = window.requestAnimationFrame(tick);
    return () => window.cancelAnimationFrame(raf);
  }, [anyPlaying]);

  useEffect(() => {
    const host = previewHostRef.current;
    if (!host) return;
    const update = () => {
      const r = host.getBoundingClientRect();
      setPreviewSize({ w: Math.max(1, r.width), h: Math.max(1, r.height) });
    };
    update();
    const ro = new ResizeObserver(update);
    ro.observe(host);
    return () => ro.disconnect();
  }, []);

  function audioStatus(assetId: string): { label: string; detail?: string } {
    const el = audioElsRef.current.get(assetId) ?? null;
    if (!el) return { label: 'URL не получен', detail: 'Не удалось получить dnd://asset URL для аудио.' };
    const meta = audioMetaRef.current.get(assetId) ?? { lastPlayError: null };
    if (meta.lastPlayError) return { label: 'Ошибка/блок', detail: meta.lastPlayError };
    if (el.error)
      return {
        label: 'Ошибка',
        detail: `MediaError code=${String(el.error.code)} (1=ABORTED, 2=NETWORK, 3=DECODE, 4=SRC_NOT_SUPPORTED)`,
      };
    if (el.readyState < 2) return { label: 'Загрузка…' };
    if (!el.paused) return { label: 'Играет' };
    if (el.currentTime > 0) return { label: 'Пауза' };
    return { label: 'Остановлено' };
  }
  const nextScenes = useMemo(() => {
    if (!project) return [];
    if (!currentGraphNodeId) return [];
    const outgoing = project.sceneGraphEdges
      .filter((e) => e.sourceGraphNodeId === currentGraphNodeId)
      .map((e) => {
        const n = project.sceneGraphNodes.find((x) => x.id === e.targetGraphNodeId);
        return n ? { graphNodeId: e.targetGraphNodeId, sceneId: n.sceneId } : null;
      })
      .filter((x): x is { graphNodeId: GraphNodeId; sceneId: SceneId } => Boolean(x));
    return outgoing
      .map((o) => ({ graphNodeId: o.graphNodeId, scene: project.scenes[o.sceneId] }))
      .filter((x): x is { graphNodeId: GraphNodeId; scene: Scene } => x.scene !== undefined);
  }, [currentGraphNodeId, project]);

  const tool = fxState?.tool ?? { tool: 'fog', radiusN: 0.08, intensity: 0.6 };

  function toNPoint(e: React.PointerEvent): { x: number; y: number } | null {
    const host = previewHostRef.current;
    if (!host) return null;
    const r = host.getBoundingClientRect();
    const cr = previewContentRect;
    const ox = cr ? cr.x : 0;
    const oy = cr ? cr.y : 0;
    const cw = cr ? cr.w : r.width;
    const ch = cr ? cr.h : r.height;
    const x = (e.clientX - (r.left + ox)) / Math.max(1, cw);
    const y = (e.clientY - (r.top + oy)) / Math.max(1, ch);
    return { x: Math.max(0, Math.min(1, x)), y: Math.max(0, Math.min(1, y)) };
  }

  async function commitStroke(): Promise<void> {
    if (isVideoPreviewScene) {
      brushRef.current = null;
      setDraftFxTick((x) => x + 1);
      return;
    }
    if (!fxState) return;
    const b = brushRef.current;
    if (!b) return;
    const createdAtMs = Date.now();
    const seed = Math.floor(Math.random() * 1_000_000_000);

    if (b.tool === 'fog' && b.points && b.points.length > 0) {
      await fx.dispatch({
        kind: 'instance.add',
        instance: {
          id: `fog_${String(createdAtMs)}_${String(seed)}`,
          type: 'fog',
          seed,
          createdAtMs,
          points: b.points,
          radiusN: tool.radiusN,
          opacity: Math.max(0.05, Math.min(0.9, tool.intensity)),
          lifetimeMs: null,
        },
      });
    }
    if (b.tool === 'fire' && b.points && b.points.length > 0) {
      await fx.dispatch({
        kind: 'instance.add',
        instance: {
          id: `fire_${String(createdAtMs)}_${String(seed)}`,
          type: 'fire',
          seed,
          createdAtMs,
          points: b.points,
          radiusN: tool.radiusN,
          // Огонь визуально ярче, но всё равно ограничиваемся безопасными пределами.
          opacity: Math.max(0.12, Math.min(0.95, tool.intensity)),
          lifetimeMs: null,
        },
      });
    }
    if (b.tool === 'rain' && b.points && b.points.length > 0) {
      await fx.dispatch({
        kind: 'instance.add',
        instance: {
          id: `rain_${String(createdAtMs)}_${String(seed)}`,
          type: 'rain',
          seed,
          createdAtMs,
          points: b.points,
          radiusN: tool.radiusN,
          opacity: Math.max(0.08, Math.min(0.9, tool.intensity)),
          lifetimeMs: null,
        },
      });
    }
    if (b.tool === 'lightning' && b.startN && b.points && b.points.length > 0) {
      const last = b.points[b.points.length - 1];
      if (last === undefined) return;
      const end = { x: last.x, y: last.y };
      const start = { x: end.x, y: 0 };
      await fx.dispatch({
        kind: 'instance.add',
        instance: {
          id: `lt_${String(createdAtMs)}_${String(seed)}`,
          type: 'lightning',
          seed,
          createdAtMs,
          start,
          end,
          widthN: Math.max(0.01, tool.radiusN * 0.9),
          intensity: Math.max(0.9, Math.min(1.2, tool.intensity * 1.35)),
          lifetimeMs: 180,
        },
      });
      await fx.dispatch({
        kind: 'instance.add',
        instance: {
          id: `sc_${String(createdAtMs)}_${String(seed)}`,
          type: 'scorch',
          seed: seed ^ 0x5a5a5a,
          createdAtMs,
          at: end,
          radiusN: Math.max(0.03, tool.radiusN * 0.625),
          opacity: 0.92,
          lifetimeMs: 60_000,
        },
      });
    }
    if (b.tool === 'freeze' && b.points && b.points.length > 0) {
      const last = b.points[b.points.length - 1];
      if (last === undefined) return;
      const at = { x: last.x, y: last.y };
      await fx.dispatch({
        kind: 'instance.add',
        instance: {
          id: `fr_${String(createdAtMs)}_${String(seed)}`,
          type: 'freeze',
          seed,
          createdAtMs,
          at,
          intensity: Math.max(0.8, Math.min(1.25, tool.intensity * 1.15)),
          // Быстро появиться → чуть задержаться → плавно исчезнуть.
          lifetimeMs: 820,
        },
      });
      await fx.dispatch({
        kind: 'instance.add',
        instance: {
          id: `ice_${String(createdAtMs)}_${String(seed)}`,
          type: 'ice',
          seed: seed ^ 0x33cc99,
          createdAtMs,
          at,
          radiusN: Math.max(0.03, tool.radiusN * 0.9),
          opacity: 0.85,
          lifetimeMs: 60_000,
        },
      });
    }
    brushRef.current = null;
    setDraftFxTick((x) => x + 1);
  }
  const draftInstance = useMemo(() => {
    const b = brushRef.current;
    if (!b) return null;
    const seed = 12345;
    const createdAtMs = Date.now();
    if (b.tool === 'fog' && b.points && b.points.length > 0) {
      return {
        id: '__draft__',
        type: 'fog' as const,
        seed,
        createdAtMs,
        points: b.points,
        radiusN: tool.radiusN,
        opacity: Math.max(0.05, Math.min(0.6, tool.intensity * 0.7)),
        lifetimeMs: null,
      };
    }
    if (b.tool === 'fire' && b.points && b.points.length > 0) {
      return {
        id: '__draft__',
        type: 'fire' as const,
        seed,
        createdAtMs,
        points: b.points,
        radiusN: tool.radiusN,
        opacity: Math.max(0.12, Math.min(0.75, tool.intensity * 0.85)),
        lifetimeMs: null,
      };
    }
    if (b.tool === 'rain' && b.points && b.points.length > 0) {
      return {
        id: '__draft__',
        type: 'rain' as const,
        seed,
        createdAtMs,
        points: b.points,
        radiusN: tool.radiusN,
        opacity: Math.max(0.08, Math.min(0.65, tool.intensity * 0.85)),
        lifetimeMs: null,
      };
    }
    if (b.tool === 'lightning' && b.startN && b.points && b.points.length > 0) {
      const last = b.points[b.points.length - 1];
      if (last === undefined) return null;
      return {
        id: '__draft__',
        type: 'lightning' as const,
        seed,
        createdAtMs,
        start: { x: last.x, y: 0 },
        end: { x: last.x, y: last.y },
        widthN: Math.max(0.01, tool.radiusN * 0.9),
        intensity: Math.max(0.9, Math.min(1.2, tool.intensity * 1.35)),
        lifetimeMs: 180,
      };
    }
    if (b.tool === 'freeze' && b.points && b.points.length > 0) {
      const last = b.points[b.points.length - 1];
      if (last === undefined) return null;
      return {
        id: '__draft__',
        type: 'freeze' as const,
        seed,
        createdAtMs,
        at: { x: last.x, y: last.y },
        intensity: Math.max(0.8, Math.min(1.25, tool.intensity * 1.15)),
        lifetimeMs: 240,
      };
    }
    return null;
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [draftFxTick, tool.intensity, tool.radiusN, tool.tool]);

  const fxMergedState = useMemo(() => {
    if (!fxState) return null;
    if (!draftInstance) return fxState;
    return { ...fxState, instances: [...fxState.instances, draftInstance] };
  }, [draftInstance, fxState]);

  return (
    <div className={styles.page}>
      <Surface className={styles.remote}>
        <div className={styles.remoteTitle}>ПУЛЬТ УПРАВЛЕНИЯ</div>
        <div className={styles.spacer12} />
        {!isVideoPreviewScene ? (
          <>
            <div className={styles.sectionLabel}>ЭФФЕКТЫ</div>
            <div className={styles.spacer8} />
            <div className={styles.effectsStack}>
              <div className={styles.iconRow}>
                <Button
                  variant={tool.tool === 'fog' ? 'primary' : 'ghost'}
                  iconOnly
                  title="Туман"
                  ariaLabel="Туман"
                  onClick={() => void fx.dispatch({ kind: 'tool.set', tool: { ...tool, tool: 'fog' } })}
                >
                  <span className={styles.iconGlyph}>🌫️</span>
                </Button>
                <Button
                  variant={tool.tool === 'fire' ? 'primary' : 'ghost'}
                  iconOnly
                  title="Огонь"
                  ariaLabel="Огонь"
                  onClick={() => void fx.dispatch({ kind: 'tool.set', tool: { ...tool, tool: 'fire' } })}
                >
                  <span className={styles.iconGlyph}>🔥</span>
                </Button>
                <Button
                  variant={tool.tool === 'rain' ? 'primary' : 'ghost'}
                  iconOnly
                  title="Дождь"
                  ariaLabel="Дождь"
                  onClick={() => void fx.dispatch({ kind: 'tool.set', tool: { ...tool, tool: 'rain' } })}
                >
                  <span className={styles.iconGlyph}>🌧️</span>
                </Button>
                <Button
                  variant={tool.tool === 'lightning' ? 'primary' : 'ghost'}
                  iconOnly
                  title="Молния"
                  ariaLabel="Молния"
                  onClick={() => void fx.dispatch({ kind: 'tool.set', tool: { ...tool, tool: 'lightning' } })}
                >
                  <span className={styles.iconGlyph}>⚡</span>
                </Button>
                <Button
                  variant={tool.tool === 'freeze' ? 'primary' : 'ghost'}
                  iconOnly
                  title="Заморозка"
                  ariaLabel="Заморозка"
                  onClick={() => void fx.dispatch({ kind: 'tool.set', tool: { ...tool, tool: 'freeze' } })}
                >
                  <span className={styles.iconGlyph}>❄️</span>
                </Button>
                <Button
                  variant={tool.tool === 'eraser' ? 'primary' : 'ghost'}
                  iconOnly
                  title="Ластик"
                  ariaLabel="Ластик"
                  onClick={() => void fx.dispatch({ kind: 'tool.set', tool: { ...tool, tool: 'eraser' } })}
                >
                  <span className={styles.iconGlyph}>🧹</span>
                </Button>
                <Button
                  variant="ghost"
                  iconOnly
                  title="Очистить эффекты"
                  ariaLabel="Очистить эффекты"
                  onClick={() => void fx.dispatch({ kind: 'instances.clear' })}
                >
                  <span className={styles.clearIcon}>
                    <svg viewBox="0 0 24 24" width="20" height="20" aria-hidden>
                      <circle cx="12" cy="12" r="8" fill="none" stroke="#e5484d" strokeWidth="2" />
                      <line
                        x1="7"
                        y1="17"
                        x2="17"
                        y2="7"
                        stroke="#e5484d"
                        strokeWidth="2"
                        strokeLinecap="round"
                      />
                    </svg>
                  </span>
                </Button>
              </div>
              <div className={styles.radiusRow}>
                <div className={styles.radiusLabel}>Радиус кисти</div>
                <input
                  type="range"
                  min={0.015}
                  max={0.18}
                  step={0.001}
                  value={tool.radiusN}
                  onChange={(e) => {
                    const v = Number((e.currentTarget as HTMLInputElement).value);
                    const next = Math.max(0.01, Math.min(0.25, Number.isFinite(v) ? v : tool.radiusN));
                    void fx.dispatch({ kind: 'tool.set', tool: { ...tool, radiusN: next } });
                  }}
                  className={styles.range}
                  aria-label="Радиус кисти"
                />
                <div className={styles.radiusValue}>{Math.round(tool.radiusN * 100)}</div>
              </div>
            </div>
            <div className={styles.spacer12} />
          </>
        ) : null}
        <div className={styles.storyWrap}>
          <div className={styles.sectionLabel}>СЮЖЕТНАЯ ЛИНИЯ</div>
          <div className={styles.spacer10} />
          <div className={styles.storyScroll}>
            {history.map((gnId, idx) => {
              const gn = project?.sceneGraphNodes.find((n) => n.id === gnId);
              const s = gn ? project?.scenes[gn.sceneId] : undefined;
              const isCurrent = gnId === project?.currentGraphNodeId;
              return (
                <button
                  type="button"
                  key={`${gnId}_${String(idx)}`}
                  disabled={!project || isCurrent}
                  className={[styles.historyBtn, isCurrent ? styles.historyBtnCurrent : '']
                    .filter(Boolean)
                    .join(' ')}
                  title={project && !isCurrent ? 'Перейти к этой сцене' : undefined}
                  onClick={() => {
                    if (!project) return;
                    if (isCurrent) return;
                    // Перемотка: переходим на выбранный шаг без добавления нового пункта в историю.
                    suppressNextHistoryPushRef.current = true;
                    void api.invoke(ipcChannels.project.setCurrentGraphNode, { graphNodeId: gnId });
                  }}
                >
                  {isCurrent ? (
                    <div className={styles.historyBadge}>ТЕКУЩАЯ СЦЕНА</div>
                  ) : (
                    <div className={styles.historyMuted}>Пройдено</div>
                  )}
                  <div className={styles.historyTitle}>{s?.title ?? (gn ? String(gn.sceneId) : gnId)}</div>
                </button>
              );
            })}
            {history.length === 0 ? <div className={styles.emptyStory}>Нет активной сцены.</div> : null}
          </div>
        </div>
      </Surface>

      <div className={styles.rightStack}>
        <Surface className={styles.surfacePad}>
          <div className={styles.previewHeader}>
            <div className={styles.previewTitle}>Предпросмотр экрана</div>
            <div className={styles.previewActions}>
              <Button onClick={() => void api.invoke(ipcChannels.windows.closeMultiWindow, {})}>
                Выключить демонстрацию
              </Button>
            </div>
          </div>
          <div className={styles.spacer10} />
          {isVideoPreviewScene ? (
            <div className={styles.videoHint}>
              Видео-превью: кисть эффектов отключена (как на экране демонстрации — оверлей только для
              изображения).
            </div>
          ) : null}
          <div className={styles.spacer10} />
          <div className={styles.previewFrame}>
            <div ref={previewHostRef} className={styles.previewHost}>
              <ControlScenePreview
                session={session}
                videoRef={previewVideoRef}
                onContentRectChange={setPreviewContentRect}
              />
            </div>
            {!isVideoPreviewScene ? (
              <>
                <PixiEffectsOverlay
                  state={fxMergedState}
                  style={{ zIndex: 1 }}
                  viewport={
                    previewContentRect
                      ? {
                          x: previewContentRect.x,
                          y: previewContentRect.y,
                          w: previewContentRect.w,
                          h: previewContentRect.h,
                        }
                      : undefined
                  }
                />
                {cursorN ? (
                  <div
                    className={styles.brushCursor}
                    style={{
                      left:
                        (previewContentRect ? previewContentRect.x : 0) +
                        cursorN.x * (previewContentRect ? previewContentRect.w : previewSize.w),
                      top:
                        (previewContentRect ? previewContentRect.y : 0) +
                        cursorN.y * (previewContentRect ? previewContentRect.h : previewSize.h),
                      width:
                        tool.radiusN *
                        Math.min(
                          previewContentRect ? previewContentRect.w : previewSize.w,
                          previewContentRect ? previewContentRect.h : previewSize.h,
                        ) *
                        2,
                      height:
                        tool.radiusN *
                        Math.min(
                          previewContentRect ? previewContentRect.w : previewSize.w,
                          previewContentRect ? previewContentRect.h : previewSize.h,
                        ) *
                        2,
                    }}
                  />
                ) : null}
                <div
                  className={styles.brushLayer}
                  onPointerEnter={(e) => {
                    const p = toNPoint(e);
                    if (!p) return;
                    setCursorN(p);
                  }}
                  onPointerLeave={() => setCursorN(null)}
                  onPointerDown={(e) => {
                    const p = toNPoint(e);
                    if (!p) return;
                    setCursorN(p);
                    (e.currentTarget as HTMLDivElement).setPointerCapture(e.pointerId);
                    if (tool.tool === 'eraser') {
                      const rN = tool.radiusN;
                      const nearest = (fxState?.instances ?? [])
                        .map((inst) => {
                          if (inst.type === 'fog') {
                            const d = inst.points.reduce((best, q) => {
                              const dx = q.x - p.x;
                              const dy = q.y - p.y;
                              const dd = dx * dx + dy * dy;
                              return Math.min(best, dd);
                            }, Number.POSITIVE_INFINITY);
                            return { id: inst.id, dd: d };
                          }
                          if (inst.type === 'lightning') {
                            const dx = inst.end.x - p.x;
                            const dy = inst.end.y - p.y;
                            return { id: inst.id, dd: dx * dx + dy * dy };
                          }
                          if (inst.type === 'freeze') {
                            const dx = inst.at.x - p.x;
                            const dy = inst.at.y - p.y;
                            return { id: inst.id, dd: dx * dx + dy * dy };
                          }
                          return { id: inst.id, dd: Number.POSITIVE_INFINITY };
                        })
                        .sort((a, b) => a.dd - b.dd)[0];
                      if (nearest && nearest.dd <= rN * rN) {
                        void fx.dispatch({ kind: 'instance.remove', id: nearest.id });
                      }
                      return;
                    }
                    brushRef.current = {
                      tool: tool.tool,
                      startN: p,
                      points: [{ x: p.x, y: p.y, tMs: Date.now() }],
                    };
                    setDraftFxTick((x) => x + 1);
                  }}
                  onPointerMove={(e) => {
                    const b = brushRef.current;
                    const p = toNPoint(e);
                    if (!p) return;
                    setCursorN(p);
                    if (!b?.points) return;
                    const last = b.points[b.points.length - 1];
                    if (!last) return;
                    const dx = p.x - last.x;
                    const dy = p.y - last.y;
                    const minStep = Math.max(0.004, tool.radiusN * 0.25);
                    if (dx * dx + dy * dy < minStep * minStep) return;
                    b.points.push({ x: p.x, y: p.y, tMs: Date.now() });
                    setDraftFxTick((x) => x + 1);
                  }}
                  onPointerUp={() => {
                    void commitStroke();
                  }}
                  onPointerCancel={() => {
                    brushRef.current = null;
                    setDraftFxTick((x) => x + 1);
                  }}
                />
              </>
            ) : null}
          </div>
        </Surface>

        <Surface className={styles.surfacePad}>
          <div className={styles.branchTitle}>Варианты ветвления</div>
          <div className={styles.branchGrid}>
            {nextScenes.map((o, i) => (
              <div key={o.graphNodeId} className={styles.branchCard}>
                <div className={styles.branchCardHeader}>
                  <div className={styles.branchOption}>ОПЦИЯ {String(i + 1)}</div>
                </div>
                <div className={styles.branchName}>{o.scene.title || 'Без названия'}</div>
                <Button
                  variant="primary"
                  onClick={() =>
                    void api.invoke(ipcChannels.project.setCurrentGraphNode, { graphNodeId: o.graphNodeId })
                  }
                >
                  Переключить
                </Button>
              </div>
            ))}
            {nextScenes.length === 0 ? (
              <div className={styles.branchEmpty}>
                <div>Нет вариантов перехода.</div>
                <Button
                  variant="primary"
                  disabled={!session?.project?.currentGraphNodeId}
                  onClick={() => void api.invoke(ipcChannels.windows.closeMultiWindow, {})}
                >
                  Завершить показ
                </Button>
              </div>
            ) : null}
          </div>
        </Surface>

        <Surface className={styles.surfacePad}>
          <div className={styles.musicHeader}>
            <div className={styles.previewTitle}>Музыка</div>
          </div>
          <div className={styles.spacer10} />
          {sceneAudios.length === 0 ? (
            <div className={styles.musicEmpty}>В текущей сцене нет аудио.</div>
          ) : (
            <div className={styles.audioList}>
              {sceneAudios.map(({ ref, asset }) => {
                const el = audioElsRef.current.get(ref.assetId) ?? null;
                const st = audioStatus(ref.assetId);
                const dur = el?.duration && Number.isFinite(el.duration) ? el.duration : 0;
                const cur = el?.currentTime && Number.isFinite(el.currentTime) ? el.currentTime : 0;
                const pct = dur > 0 ? Math.max(0, Math.min(1, cur / dur)) : 0;
                return (
                  <div key={ref.assetId} className={styles.audioCard}>
                    <div className={styles.audioMeta}>
                      <div className={styles.audioName}>{asset.originalName}</div>
                      <div className={styles.audioBadges}>
                        <div>{ref.autoplay ? 'Авто' : 'Ручн.'}</div>
                        <div>{ref.loop ? 'Цикл' : 'Один раз'}</div>
                        <div title={st.detail}>{st.label}</div>
                      </div>
                      <div className={styles.spacer10} />
                      <div
                        role="slider"
                        aria-valuemin={0}
                        aria-valuemax={dur > 0 ? Math.round(dur) : 0}
                        aria-valuenow={Math.round(cur)}
                        tabIndex={0}
                        onKeyDown={(e) => {
                          if (!el) return;
                          if (!dur) return;
                          if (e.key === 'ArrowLeft') el.currentTime = Math.max(0, el.currentTime - 5);
                          if (e.key === 'ArrowRight') el.currentTime = Math.min(dur, el.currentTime + 5);
                          setAudioStateTick((x) => x + 1);
                        }}
                        onClick={(e) => {
                          if (!el) return;
                          if (!dur) return;
                          const rect = (e.currentTarget as HTMLDivElement).getBoundingClientRect();
                          const next = (e.clientX - rect.left) / rect.width;
                          el.currentTime = Math.max(0, Math.min(dur, next * dur));
                          setAudioStateTick((x) => x + 1);
                        }}
                        className={[
                          styles.audioScrub,
                          dur > 0 ? styles.audioScrubPointer : styles.audioScrubDefault,
                        ].join(' ')}
                        title={dur > 0 ? 'Клик — перемотка' : 'Длительность неизвестна'}
                      >
                        <div
                          className={styles.scrubFill}
                          style={{ width: `${String(Math.round(pct * 100))}%` }}
                        />
                      </div>
                      <div className={styles.timeRow}>
                        <div>{formatTime(cur)}</div>
                        <div>{dur ? formatTime(dur) : '—:—'}</div>
                      </div>
                    </div>
                    <div className={styles.audioTransport}>
                      <Button
                        variant="primary"
                        onClick={() => {
                          if (!el) return;
                          const m = audioMetaRef.current.get(ref.assetId) ?? { lastPlayError: null };
                          audioMetaRef.current.set(ref.assetId, { ...m, lastPlayError: null });
                          void el.play().catch(() => {
                            const mm = audioMetaRef.current.get(ref.assetId) ?? { lastPlayError: null };
                            audioMetaRef.current.set(ref.assetId, {
                              ...mm,
                              lastPlayError: 'Не удалось запустить.',
                            });
                            setAudioStateTick((x) => x + 1);
                          });
                        }}
                      >
                        ▶
                      </Button>
                      <Button
                        onClick={() => {
                          if (!el) return;
                          el.pause();
                        }}
                      >
                        ❚❚
                      </Button>
                      <Button
                        onClick={() => {
                          if (!el) return;
                          el.pause();
                          el.currentTime = 0;
                          setAudioStateTick((x) => x + 1);
                        }}
                      >
                        ■
                      </Button>
                    </div>
                  </div>
                );
              })}
            </div>
          )}
        </Surface>
      </div>
    </div>
  );
}
