import React, {
  useCallback,
  useEffect,
  useLayoutEffect,
  useMemo,
  useRef,
  useState,
  useSyncExternalStore,
} from 'react';
import { resolveDocumentAssetUrl } from '../asset_manager';
import { formatTransform } from './math';
import useDocumentDrag from './useDocumentDrag';
import PreviewZoomOverlay from '../detail/PreviewZoomOverlay';
import {
  WorkspaceEngine,
  DESK_CANVAS_PADDING,
  DESK_DEFAULT_CANVAS_HEIGHT,
  DESK_DEFAULT_CANVAS_WIDTH,
  clampCardDimensions,
  computeFallbackCardSize,
  useWorkspaceSnapshot,
} from './workspaceEngine';
import useDeskPointer from './pointer/useDeskPointer';
import useDeskTagInteractions from './tags/useDeskTagInteractions';
import DesktopDocumentCard from './DesktopDocumentCard';
import usePreviewMetadata from './hooks/usePreviewMetadata';
import '../styles/workspace/workspace-layout.css';
import '../styles/workspace/workspace-items.css';
import '../styles/workspace/workspace-cards.css';

type Identifier = string | number;

type TagLike = { id?: Identifier | null; label?: string; color?: string | null } | null | undefined;

export interface DeskDocument {
  id?: Identifier | null;
  title?: string;
  tags?: TagLike[] | null;
  [key: string]: unknown;
}

interface NavigatorSnapshot {
  url: string | null;
  alt?: string | null;
  canGoPrev?: boolean;
  canGoNext?: boolean;
  goPrev?: () => void;
  goNext?: () => void;
  ordinal?: number | null;
  width?: number | null;
  height?: number | null;
}

interface OverlayOriginTransform {
  rotation: number;
  scaleX: number;
  scaleY: number;
  baseWidth: number;
  baseHeight: number;
}

interface OverlayDisplay extends NavigatorSnapshot {
  url: string;
}

interface DocumentSizeInfo {
  width: number;
  height: number;
  source?: 'snapshot' | 'metadata' | 'fallback';
}

interface PreviewMetadataEntry {
  docId: string;
  width: number;
  height: number;
}

interface DragTransformOverride {
  centerX?: number;
  centerY?: number;
  rotation?: number;
  scale?: number;
}

interface DragSettings {
  canvasPadding: number;
  defaultCanvasWidth: number;
  defaultCanvasHeight: number;
  debugDrag?: boolean;
}

interface LayoutEntry {
  centerX: number;
  centerY: number;
  rotation: number;
  z: number;
  width?: number;
  height?: number;
}

type WorkspaceSnapshotState = {
  layout: Map<string, LayoutEntry>;
  canvasSize: { width: number; height: number };
  visibleDocIds: Set<string>;
  draggingId: string | null;
  tagDropTargetId: string | null;
  pendingTagDocId: string | null;
  pendingRemovalTag: unknown;
  initialLoadDone: boolean;
};

interface DesktopWorkspaceProps {
  documents?: DeskDocument[];
  searchResults?: DeskDocument[] | null;
  onDocumentOpen?: (docId: Identifier | null, options?: Record<string, unknown>) => void;
  onInspectDocument?: (...args: unknown[]) => void;
  onEntryPointer?: (...args: unknown[]) => void;
  onDocumentStackSelect?: (docIds: Identifier[]) => void;
  onPromoteSelection?: (...args: unknown[]) => void;
  onAssignTagToDocument?: (...args: unknown[]) => void;
  onRemoveTagFromDocument?: (...args: unknown[]) => void;
  ensureAssetUrl?: (...args: unknown[]) => Promise<unknown> | unknown;
  getDocumentAsset?: (...args: unknown[]) => unknown;
  activeTagIds?: Array<Identifier | null | undefined>;
  selectedDocumentIds?: Identifier[];
  onClearSelection?: () => void;
  detailPanelOpen?: boolean;
  onCloseDetailPanel?: () => void;
  tenantId?: Identifier | null;
  viewId?: string | null;
}

interface DesktopWorkspaceViewProps {
  engine: WorkspaceEngine;
  items: DeskDocument[];
  containerRef: React.RefObject<HTMLDivElement>;
  handleCanvasDragOver: (event: React.DragEvent<HTMLDivElement>) => void;
  handleCanvasDragLeave: (event: React.DragEvent<HTMLDivElement>) => void;
  handleCanvasDrop: (event: React.DragEvent<HTMLDivElement>) => void;
  ensureDocumentSize: (doc: DeskDocument | null | undefined) => DocumentSizeInfo | null;
  layoutSnapshot: Map<string, LayoutEntry>;
  layoutRef: React.MutableRefObject<Map<string, LayoutEntry>>;
  dragTransformsRef: React.MutableRefObject<Map<string, DragTransformOverride>>;
  itemRefs: React.MutableRefObject<Map<string, HTMLDivElement | null>>;
  visibleDocIds: Set<string>;
  draggingId: string | null;
  tagDropTargetId: string | null;
  pendingTagDocId: string | null;
  pendingRemovalTag: unknown;
  onDocumentOpen?: DesktopWorkspaceProps['onDocumentOpen'];
  ensureAssetUrl?: DesktopWorkspaceProps['ensureAssetUrl'];
  getDocumentAsset?: DesktopWorkspaceProps['getDocumentAsset'];
  handleNavigatorSnapshot: (docId: Identifier | null, snapshot: NavigatorSnapshot | null) => void;
  activeTagSet: Set<string>;
  handleTagDragEnterDoc: (...args: unknown[]) => void;
  handleTagDragOverDoc: (...args: unknown[]) => void;
  handleTagDragLeaveDoc: (...args: unknown[]) => void;
  handleTagDropOnDoc: (...args: unknown[]) => void;
  handleDocTagPointerDown: (...args: unknown[]) => void;
  handleDocTagDragStart: (...args: unknown[]) => void;
  handleDocTagDrag: (...args: unknown[]) => void;
  handleDocTagDragEnd: (...args: unknown[]) => void;
  overlayDisplay: OverlayDisplay | null;
  closeOverlay: () => void;
  overlayOriginRect: DOMRect | null;
  overlayOriginTransform: OverlayOriginTransform | null;
  onEntryPointer?: DesktopWorkspaceProps['onEntryPointer'];
  onDocumentStackSelect?: DesktopWorkspaceProps['onDocumentStackSelect'];
  onPromoteSelection?: DesktopWorkspaceProps['onPromoteSelection'];
  selectedDocumentIds: Identifier[];
  onClearSelection?: DesktopWorkspaceProps['onClearSelection'];
  detailPanelOpen: boolean;
  onCloseDetailPanel?: DesktopWorkspaceProps['onCloseDetailPanel'];
  documentLookup: Map<string, DeskDocument>;
  resolveBaseMetrics: (doc: DeskDocument | null | undefined, cardWidth: number, cardHeight: number) => {
    baseWidth: number;
    baseHeight: number;
    baseScale: number;
  };
  bringToFront: (docId: Identifier | null | undefined) => void;
  setDraggingId: (value: string | null) => void;
  canvasSize: { width: number; height: number };
  openOverlayForDoc: (docId: Identifier | null | undefined, originInfo?: OverlayOriginTransform | null) => void;
  recalcVisibleDocIds: () => void;
  dragSettings: DragSettings;
  onInspectDocument?: DesktopWorkspaceProps['onInspectDocument'];
  markLayoutDirty: () => void;
}

const DEBUG_DRAG = false;
const DEBUG_FOCUS = false;
const DesktopWorkspace: React.FC<DesktopWorkspaceProps> = ({
  documents = [],
  searchResults = null,
  onDocumentOpen,
  onInspectDocument = null,
  onEntryPointer = null,
  onDocumentStackSelect = null,
  onPromoteSelection = null,
  onAssignTagToDocument = null,
  onRemoveTagFromDocument = null,
  ensureAssetUrl = null,
  getDocumentAsset = () => null,
  activeTagIds = [],
  selectedDocumentIds = [],
  onClearSelection = null,
  detailPanelOpen = false,
  onCloseDetailPanel = null,
  tenantId = null,
  viewId = 'default',
}) => {
  const items = useMemo<DeskDocument[]>(
    () => (searchResults ? searchResults : documents),
    [documents, searchResults],
  );

  const allowLayoutPersistence = Boolean(tenantId && viewId && viewId.startsWith('folder:'));

  const containerRef = useRef<HTMLDivElement | null>(null);
  const itemRefs = useRef<Map<string, HTMLDivElement | null>>(new Map());
  const dragTransformsRef = useRef<Map<string, DragTransformOverride>>(new Map());
  const [overlayDocId, setOverlayDocId] = useState<string | null>(null);
  const [overlayOriginRect, setOverlayOriginRect] = useState<DOMRect | null>(null);
  const [overlayOriginTransform, setOverlayOriginTransform] = useState<OverlayOriginTransform | null>(
    null,
  );
  const [previewSnapshots, setPreviewSnapshots] = useState<Map<string, NavigatorSnapshot>>(
    () => new Map(),
  );
  const [docSizeVersion, setDocSizeVersion] = useState(0);
  const docSizeMapRef = useRef<Map<string, DocumentSizeInfo>>(new Map());
  const ensureDocumentSize = useCallback((doc: DeskDocument | null | undefined): DocumentSizeInfo | null => {
    if (!doc?.id) {
      return null;
    }
    return docSizeMapRef.current.get(String(doc.id)) || null;
  }, []);
  const previewMetadata = usePreviewMetadata(items, getDocumentAsset, ensureAssetUrl);
  const documentLookup = useMemo<Map<string, DeskDocument>>(() => {
    const map = new Map<string, DeskDocument>();
    items.forEach((doc) => {
      const key = doc?.id != null ? String(doc.id) : null;
      if (key) {
        map.set(key, doc);
      }
    });
    return map;
  }, [items]);

  const engineRef = useRef<WorkspaceEngine | null>(null);
  if (!engineRef.current) {
    engineRef.current = new WorkspaceEngine({
      allowLayoutPersistence,
      tenantId,
      viewId,
    });
  }
  const engine = engineRef.current as WorkspaceEngine;

  useEffect(() => {
    engine.updateConfig({ allowLayoutPersistence, tenantId, viewId });
  }, [engine, allowLayoutPersistence, tenantId, viewId]);

  useEffect(() => {
    const nextItems = searchResults ? searchResults : documents;
    engine.setItems(nextItems || []);
  }, [engine, documents, searchResults]);

  useEffect(() => {
    const map = new Map();
    items.forEach((doc) => {
      const key = doc?.id != null ? String(doc.id) : null;
      if (key) {
        map.set(key, doc);
      }
    });
    engine.setDocumentLookup(map);
  }, [engine, items]);

  useEffect(() => {
    engine.setEnsureDocumentSize(ensureDocumentSize);
  }, [engine, ensureDocumentSize]);

  const workspaceSnapshot = useWorkspaceSnapshot(engine, useSyncExternalStore) as WorkspaceSnapshotState;
  const {
    layout: layoutSnapshot,
    canvasSize,
    visibleDocIds,
    draggingId,
    tagDropTargetId,
    pendingTagDocId,
    pendingRemovalTag,
    initialLoadDone,
  } = workspaceSnapshot;

  useEffect(() => {
    const shouldWaitForPersisted = allowLayoutPersistence && !initialLoadDone;

    if (shouldWaitForPersisted) {
      return;
    }

    engine.ensureLayoutForItems();
  }, [engine, docSizeVersion, initialLoadDone, items.length, allowLayoutPersistence]);

  useEffect(() => {
    engine.setItemRefs(itemRefs);
  }, [engine, itemRefs]);

  const layoutRef = useRef<Map<string, LayoutEntry>>(layoutSnapshot);
  layoutRef.current = engine.layout as Map<string, LayoutEntry>;

  const bringToFront = useCallback((docId: Identifier | null | undefined) => {
    engine.bringToFront(docId);
  }, [engine]);

  const markLayoutDirty = useCallback(() => {
    engine.markLayoutDirty();
  }, [engine]);

  const recalcVisibleDocIds = useCallback(() => {
    engine.recalcVisibleDocIds();
  }, [engine]);

  const setDraggingId = useCallback((value: string | number | null) => {
    engine.setDraggingId(value);
  }, [engine]);

  const applySnapshotDimensions = useCallback((docKey: string, snapshot: NavigatorSnapshot | null) => {
    const width = Number(snapshot?.width);
    const height = Number(snapshot?.height);
    if (!Number.isFinite(width) || !Number.isFinite(height) || width <= 0 || height <= 0) {
      return;
    }
    const normalized = clampCardDimensions(width, height);
    if (!normalized) {
      return;
    }
    const existing = docSizeMapRef.current.get(docKey);
    if (existing && existing.width === normalized.width && existing.height === normalized.height) {
      return;
    }
    const next = new Map(docSizeMapRef.current);
    next.set(docKey, { ...normalized, source: 'snapshot' });
    docSizeMapRef.current = next;
    setDocSizeVersion((value) => value + 1);
  }, []);
  const handleNavigatorSnapshot = useCallback(
    (docId: Identifier | null, snapshot: NavigatorSnapshot | null) => {
      const docKey = docId != null ? String(docId) : null;
      if (!docKey) {
        return;
      }

      setPreviewSnapshots((previous) => {
        const prevSnapshot = previous.get(docKey);
        if (!snapshot) {
          if (!previous.has(docKey)) {
            return previous;
          }
          const next = new Map(previous);
          next.delete(docKey);
          return next;
        }

        const next = new Map(previous);
        const sameSnapshot =
          prevSnapshot &&
          prevSnapshot.url === snapshot.url &&
          prevSnapshot.alt === snapshot.alt &&
          prevSnapshot.canGoPrev === snapshot.canGoPrev &&
          prevSnapshot.canGoNext === snapshot.canGoNext &&
          prevSnapshot.goPrev === snapshot.goPrev &&
          prevSnapshot.goNext === snapshot.goNext &&
          prevSnapshot.ordinal === snapshot.ordinal &&
          prevSnapshot.width === snapshot.width &&
          prevSnapshot.height === snapshot.height;
        if (sameSnapshot) {
          return previous;
        }
        next.set(docKey, snapshot);
        return next;
      });

      if (snapshot) {
        applySnapshotDimensions(docKey, snapshot);
      }
    },
    [applySnapshotDimensions],
  );
  const activeTagSet = useMemo<Set<string>>(() => {
    if (!Array.isArray(activeTagIds) || activeTagIds.length === 0) {
      return new Set();
    }
    const set = new Set<string>();
    activeTagIds.forEach((id) => {
      if (id != null) {
        set.add(String(id));
      }
    });
    return set;
  }, [activeTagIds]);

  useLayoutEffect(() => {
    const container = containerRef.current;
    if (!container) {
      engine.setCanvasSize({ width: 0, height: 0 });
      return undefined;
    }

    const commitSize = () => {
      const rect = container.getBoundingClientRect();
      const width = Math.floor(rect.width) || 0;
      const height = Math.floor(rect.height) || 0;
      engine.setCanvasSize({ width, height });
    };

    commitSize();

    if (typeof window.ResizeObserver === 'undefined') {
      window.addEventListener('resize', commitSize);
      return () => {
        window.removeEventListener('resize', commitSize);
      };
    }

    const observer = new window.ResizeObserver(commitSize);
    observer.observe(container);
    return () => observer.disconnect();
  }, [engine]);

  const resolvePreviewDimensions = useCallback(
    (doc: DeskDocument | null | undefined): PreviewMetadataEntry | null => {
      if (!doc?.id) {
        return null;
      }
      return previewMetadata.get(String(doc.id)) || null;
    },
    [previewMetadata],
  );

  useEffect(() => {
    if (!ensureAssetUrl) {
      return;
    }

    visibleDocIds.forEach((docId) => {
      const doc = documentLookup.get(docId);
      if (!doc) {
        return;
      }
      resolveDocumentAssetUrl(doc, 'preview', {
        ensureAssetUrl,
        getAsset: getDocumentAsset,
      });
    });
  }, [visibleDocIds, ensureAssetUrl, getDocumentAsset, documentLookup]);

  const requestCanvasFocus = useCallback(() => {
    const canvas = containerRef.current;
    if (!canvas?.focus) {
      return;
    }

    const focusTarget = () => {
      try {
        canvas.focus({ preventScroll: true });
      } catch (error: unknown) {
        if (DEBUG_FOCUS) {
          void error;
        }
      }
    };

    const raf = window.requestAnimationFrame;
    if (raf) {
      raf(() => focusTarget());
      return;
    }
    setTimeout(() => {
      focusTarget();
    }, 0);
  }, []);

  const tagInteractions = useDeskTagInteractions({
    engine,
    onAssignTagToDocument,
    onRemoveTagFromDocument,
    requestCanvasFocus,
  });

  const {
    handleTagDragEnterDoc,
    handleTagDragOverDoc,
    handleTagDragLeaveDoc,
    handleTagDropOnDoc,
    handleCanvasDragOver,
    handleCanvasDragLeave,
    handleCanvasDrop,
    handleDocTagPointerDown,
    handleDocTagDragStart,
    handleDocTagDrag,
    handleDocTagDragEnd,
  } = tagInteractions;

  useEffect(() => {
    const current = docSizeMapRef.current;
    const next = new Map(current);
    const itemKeys = new Set(items.filter((doc) => doc?.id != null).map((doc) => String(doc.id)));
    let changed = false;

    items.forEach((doc) => {
      if (!doc?.id) {
        return;
      }
      const key = String(doc.id);
      const existing = next.get(key) || null;
      const meta = previewMetadata.get(key);
      if (meta) {
        const normalized = clampCardDimensions(meta.width, meta.height);
        if (normalized) {
          if (existing?.source === 'snapshot') {
            return;
          }
          if (!existing || existing.width !== normalized.width || existing.height !== normalized.height || existing.source !== 'metadata') {
            next.set(key, { ...normalized, source: 'metadata' });
            changed = true;
          }
          return;
        }
      }

      if (!existing) {
        const fallback = computeFallbackCardSize(key);
        if (fallback) {
          next.set(key, { ...fallback, source: 'fallback' });
          changed = true;
        }
      }
    });

    current.forEach((_, key) => {
      if (!itemKeys.has(key)) {
        next.delete(key);
        changed = true;
      }
    });

    if (changed) {
      docSizeMapRef.current = next;
      setDocSizeVersion((value) => value + 1);
    }
  }, [items, previewMetadata]);

  const overlayDisplay = useMemo<OverlayDisplay | null>(() => {
    if (!overlayDocId) {
      return null;
    }
    const snapshot = previewSnapshots.get(overlayDocId);
    if (!snapshot || !snapshot.url) {
      return null;
    }
    const doc = documentLookup.get(overlayDocId);
    const alt = snapshot.alt || (doc?.title as string | undefined);
    return {
      url: snapshot.url,
      alt,
      canGoPrev: snapshot.canGoPrev,
      canGoNext: snapshot.canGoNext,
      goPrev: snapshot.goPrev,
      goNext: snapshot.goNext,
    };
  }, [overlayDocId, previewSnapshots, documentLookup]);

  const closeOverlay = useCallback(() => {
    setOverlayDocId(null);
    setOverlayOriginRect(null);
    setOverlayOriginTransform(null);
  }, []);

  useEffect(() => {
    if (overlayDocId && !documentLookup.has(overlayDocId)) {
      setOverlayDocId(null);
      setOverlayOriginRect(null);
      setOverlayOriginTransform(null);
    }
  }, [overlayDocId, documentLookup]);

  const resolveBaseMetrics = useCallback(
    (doc: DeskDocument | null | undefined, cardWidth: number, cardHeight: number) => {
      const previewDims = doc ? resolvePreviewDimensions(doc) : null;
      if (previewDims?.width && previewDims?.height) {
        const baseWidth = Math.max(previewDims.width, cardWidth);
        const baseHeight = Math.max(previewDims.height, cardHeight);
        const scaleX = cardWidth / baseWidth;
        const scaleY = cardHeight / baseHeight;
        const baseScale = Math.min(scaleX, scaleY, 1);
        return {
          baseWidth,
          baseHeight,
          baseScale: Number.isFinite(baseScale) && baseScale > 0 ? baseScale : 1,
        };
      }
      return {
        baseWidth: cardWidth,
        baseHeight: cardHeight,
        baseScale: 1,
      };
    },
    [resolvePreviewDimensions],
  );
 

  useEffect(() => {
    if (draggingId && !items.some((doc) => String(doc.id) === draggingId)) {
      setDraggingId(null);
    }
  }, [draggingId, items, setDraggingId]);

  const openOverlayForDoc = useCallback(
    (docId: Identifier | null | undefined, originInfo: OverlayOriginTransform | null = null) => {
      if (!docId) {
        return;
      }
      const docKey = String(docId);
      const snapshot = previewSnapshots.get(docKey);
      if (!snapshot || !snapshot.url) {
        return;
      }
      const container = itemRefs.current.get(docKey);
      const imageNode = container
        ? container.querySelector<HTMLImageElement>('.desk-item__card img')
        : null;
      if (!container || !imageNode) {
        return;
      }
      const rect = imageNode.getBoundingClientRect();
      let originTransform = null;
      if (originInfo) {
        const { rotation = 0, scale = 1, width: originWidth, height: originHeight } = originInfo;
        originTransform = {
          rotation,
          scaleX: scale,
          scaleY: scale,
          baseWidth: originWidth,
          baseHeight: originHeight,
        };
      }
      if (!originTransform) {
        const entry = engine.getLayout(docKey);
        const doc = documentLookup.get(docKey) || null;
        const sizeInfo = ensureDocumentSize(doc);
        if (!sizeInfo) {
          return;
        }
        const { width: cardWidth, height: cardHeight } = sizeInfo;
        const { baseWidth, baseHeight, baseScale } = resolveBaseMetrics(doc, cardWidth, cardHeight);
        const effectiveWidth = baseWidth * baseScale;
        const effectiveHeight = baseHeight * baseScale;
        originTransform = {
          rotation: entry?.rotation ?? 0,
          scaleX: baseScale,
          scaleY: baseScale,
          baseWidth: Number.isFinite(effectiveWidth) && effectiveWidth > 0 ? effectiveWidth : cardWidth,
          baseHeight: Number.isFinite(effectiveHeight) && effectiveHeight > 0 ? effectiveHeight : cardHeight,
        };
      }
      bringToFront(docId);
      setOverlayOriginRect(rect);
      setOverlayOriginTransform(originTransform);
      setOverlayDocId(docKey);
    },
    [
      bringToFront,
      previewSnapshots,
      itemRefs,
      setOverlayOriginTransform,
      ensureDocumentSize,
      resolveBaseMetrics,
      documentLookup,
      engine,
    ],
  );

  const dragSettings = useMemo<DragSettings>(
    () => ({
      canvasPadding: DESK_CANVAS_PADDING,
      defaultCanvasWidth: DESK_DEFAULT_CANVAS_WIDTH,
      defaultCanvasHeight: DESK_DEFAULT_CANVAS_HEIGHT,
      debugDrag: DEBUG_DRAG,
    }),
    [],
  );

  const viewProps = useMemo<DesktopWorkspaceViewProps>(
    () => ({
      engine,
      items,
      containerRef,
      handleCanvasDragOver,
      handleCanvasDragLeave,
      handleCanvasDrop,
      ensureDocumentSize,
      layoutSnapshot,
      layoutRef,
      dragTransformsRef,
      itemRefs,
      visibleDocIds,
      draggingId,
      tagDropTargetId,
      pendingTagDocId,
      pendingRemovalTag,
      onDocumentOpen,
      ensureAssetUrl,
      getDocumentAsset,
      handleNavigatorSnapshot,
      activeTagSet,
      handleTagDragEnterDoc,
      handleTagDragOverDoc,
      handleTagDragLeaveDoc,
      handleTagDropOnDoc,
      handleDocTagPointerDown,
      handleDocTagDragStart,
      handleDocTagDrag,
      handleDocTagDragEnd,
      overlayDisplay,
      closeOverlay,
      overlayOriginRect,
      overlayOriginTransform,
      onEntryPointer,
      onDocumentStackSelect,
      onPromoteSelection,
      selectedDocumentIds,
      onClearSelection,
      detailPanelOpen,
      onCloseDetailPanel,
      documentLookup,
      resolveBaseMetrics,
      bringToFront,
      setDraggingId,
      canvasSize,
      openOverlayForDoc,
      recalcVisibleDocIds,
      dragSettings,
      onInspectDocument,
      markLayoutDirty,
    }),
    [
      activeTagSet,
      bringToFront,
      canvasSize,
      closeOverlay,
      containerRef,
      draggingId,
      dragSettings,
      engine,
      ensureAssetUrl,
      ensureDocumentSize,
      getDocumentAsset,
      dragTransformsRef,
      handleCanvasDragLeave,
      handleCanvasDragOver,
      handleCanvasDrop,
      handleDocTagDrag,
      handleDocTagDragEnd,
      handleDocTagDragStart,
      handleDocTagPointerDown,
      handleNavigatorSnapshot,
      handleTagDragEnterDoc,
      handleTagDragLeaveDoc,
      handleTagDragOverDoc,
      handleTagDropOnDoc,
      itemRefs,
      items,
      layoutRef,
      layoutSnapshot,
      onClearSelection,
      onCloseDetailPanel,
      onDocumentOpen,
      onDocumentStackSelect,
      onEntryPointer,
      onPromoteSelection,
      openOverlayForDoc,
      overlayDisplay,
      overlayOriginRect,
      overlayOriginTransform,
      documentLookup,
      pendingRemovalTag,
      pendingTagDocId,
      recalcVisibleDocIds,
      resolveBaseMetrics,
      setDraggingId,
      selectedDocumentIds,
      detailPanelOpen,
      onInspectDocument,
      markLayoutDirty,
      tagDropTargetId,
      visibleDocIds,
    ],
  );
  return <DesktopWorkspaceView {...viewProps} />;
};

function DesktopWorkspaceView({
  engine,
  items,
  containerRef,
  handleCanvasDragOver,
  handleCanvasDragLeave,
  handleCanvasDrop,
  ensureDocumentSize,
  layoutSnapshot,
  layoutRef,
  itemRefs,
  visibleDocIds,
  draggingId,
  tagDropTargetId,
  pendingTagDocId,
  pendingRemovalTag,
  onDocumentOpen,
  ensureAssetUrl,
  getDocumentAsset,
  handleNavigatorSnapshot,
  activeTagSet,
  handleTagDragEnterDoc,
  handleTagDragOverDoc,
  handleTagDragLeaveDoc,
  handleTagDropOnDoc,
  handleDocTagPointerDown,
  handleDocTagDragStart,
  handleDocTagDrag,
  handleDocTagDragEnd,
  overlayDisplay,
  closeOverlay,
  overlayOriginRect,
  overlayOriginTransform,
  onEntryPointer,
  onDocumentStackSelect,
  onPromoteSelection,
  selectedDocumentIds,
  onClearSelection,
  detailPanelOpen,
  onCloseDetailPanel,
  documentLookup,
  resolveBaseMetrics,
  bringToFront,
  setDraggingId,
  canvasSize,
  openOverlayForDoc,
  recalcVisibleDocIds,
  dragSettings,
  onInspectDocument,
  markLayoutDirty,
  dragTransformsRef,
}: DesktopWorkspaceViewProps) {
  const { handlePointerDown, handlePointerMove, handlePointerUp, handlePointerCancel } =
    useDocumentDrag({
      engine,
      layoutRef,
      dragTransformsRef,
      itemRefs,
      documentLookup,
      ensureDocumentSize,
      resolveBaseMetrics,
      bringToFront,
      setDraggingId,
      canvasSize,
      openOverlayForDoc,
      recalcVisibleDocIds,
      settings: dragSettings,
      containerRef,
      onInspectDocument,
      onDocumentStackSelect,
      selectedDocumentIds,
      markLayoutDirty,
    }) as {
      handlePointerDown: React.PointerEventHandler<HTMLElement>;
      handlePointerMove: React.PointerEventHandler<HTMLElement>;
      handlePointerUp: React.PointerEventHandler<HTMLElement>;
      handlePointerCancel: React.PointerEventHandler<HTMLElement>;
    };

  const { getCardPointerHandlers, handleShellKeyDown, focusShell } = useDeskPointer({
    containerRef,
    items,
    layoutRef,
    ensureDocumentSize,
    activeTagSet,
    handlePointerDown,
    handlePointerMove,
    handlePointerUp,
    handlePointerCancel,
    onEntryPointer,
    onDocumentStackSelect,
    onPromoteSelection,
    onDocumentOpen,
    selectedDocumentIds,
    detailPanelOpen,
    onCloseDetailPanel,
    openOverlayForDoc,
  }) as {
    getCardPointerHandlers: (doc: DeskDocument) => React.HTMLAttributes<HTMLDivElement>;
    handleShellKeyDown: React.KeyboardEventHandler<HTMLDivElement>;
    focusShell: () => void;
  };

  useEffect(() => {
    focusShell();
  }, [focusShell]);

  useEffect(() => {
    if (selectedDocumentIds.length) {
      focusShell();
    }
  }, [focusShell, selectedDocumentIds.length]);

  useEffect(() => {
    if (!detailPanelOpen) {
      focusShell();
    }
  }, [detailPanelOpen, focusShell]);



  const allSizesReady = items.every((doc) => Boolean(ensureDocumentSize(doc)));

  return (
    <>
      <div className="desk-shell" onPointerDown={(event) => {
        if (event.target === event.currentTarget) {
          onClearSelection?.();
        }
        focusShell();
      }}
      >
        <div
          className="desk-canvas"
          ref={containerRef}
          tabIndex={0}
          onKeyDown={handleShellKeyDown}
          onDragOver={handleCanvasDragOver}
          onDragLeave={handleCanvasDragLeave}
          onDrop={handleCanvasDrop}
          onPointerDown={(event) => {
            if (event.target === event.currentTarget) {
              onClearSelection?.();
            }
            focusShell();
          }}
        >
          {!allSizesReady ? (
            <div className="desk-empty">
              <p>Loading previews…</p>
            </div>
          ) : items.length === 0 ? (
            <div className="desk-empty">
              <p>No documents to show here yet. Drop files to make this space come alive.</p>
            </div>
          ) : (
            items.map((doc, index) => {
              const sizeInfo = ensureDocumentSize(doc);
              if (!sizeInfo) {
                return null;
              }
              const { width: cardWidth, height: cardHeight } = sizeInfo;
              const docKey = doc?.id != null ? String(doc.id) : null;
              const dragOverride = docKey ? dragTransformsRef.current.get(docKey) : null;
              const layout = docKey ? layoutRef.current.get(docKey) : null;
              if (!dragOverride && (!layout && (!docKey || !layoutSnapshot.has(docKey)))) {
                return null;
              }
              const centerX = dragOverride?.centerX ?? layout?.centerX;
              const centerY = dragOverride?.centerY ?? layout?.centerY;
              if (!Number.isFinite(centerX) || !Number.isFinite(centerY)) {
                return null;
              }
              const resolvedCenterX = centerX as number;
              const resolvedCenterY = centerY as number;
              const rotation = dragOverride?.rotation ?? layout?.rotation ?? 0;
              const scale = dragOverride?.scale ?? 1;
              const originX = resolvedCenterX - cardWidth / 2;
              const originY = resolvedCenterY - cardHeight / 2;
              const transform = formatTransform(
                Math.round(originX),
                Math.round(originY),
                rotation,
                scale,
              );
              const style = {
                transform,
                zIndex: layout?.z ?? 1,
                width: Math.round(cardWidth),
                height: Math.round(cardHeight),
              };
              const shouldLoad = docKey ? visibleDocIds.has(docKey) : false;
              const dragging = docKey ? draggingId === docKey : false;
              const docTagKeys = Array.isArray(doc?.tags)
                ? doc.tags
                    .map((tag) => (tag?.id != null ? String(tag.id) : null))
                    .filter((id): id is string => Boolean(id))
                : [];
              const matchesFilter =
                activeTagSet.size === 0 || docTagKeys.some((key) => activeTagSet.has(key));
              const dropActive = docKey ? tagDropTargetId === docKey : false;
              const dropPending = docKey ? pendingTagDocId === docKey : false;
              const docId = doc?.id ?? null;
              const isSelected = docId != null ? selectedDocumentIds.includes(docId) : false;
              const docTagTokens = docTagKeys.join(' ');
              const cardPointerHandlers = getCardPointerHandlers(doc) as React.HTMLAttributes<HTMLDivElement>;
              const registerNode = (node: HTMLDivElement | null) => {
                if (!docKey) {
                  return;
                }
                if (node) {
                  itemRefs.current.set(docKey, node);
                } else {
                  itemRefs.current.delete(docKey);
                }
              };

              return (
                <DesktopDocumentCard
                  key={docKey ?? `desk-doc-${index}`}
                  doc={doc}
                  style={style}
                  shouldLoad={shouldLoad}
                  dragging={dragging}
                  matchesFilter={matchesFilter}
                  tagTargetActive={dropActive}
                  tagTargetPending={dropPending}
                  selected={isSelected}
                  docTagTokens={docTagTokens}
                  ensureAssetUrl={ensureAssetUrl}
                  getDocumentAsset={getDocumentAsset}
                  handleNavigatorSnapshot={handleNavigatorSnapshot}
                  cardPointerHandlers={cardPointerHandlers}
                  onDocumentOpen={onDocumentOpen}
                  onTagDragEnter={handleTagDragEnterDoc}
                  onTagDragOver={handleTagDragOverDoc}
                  onTagDragLeave={handleTagDragLeaveDoc}
                  onTagDrop={handleTagDropOnDoc}
                  onDocTagPointerDown={handleDocTagPointerDown}
                  onDocTagDragStart={handleDocTagDragStart}
                  onDocTagDrag={handleDocTagDrag}
                  onDocTagDragEnd={handleDocTagDragEnd}
                  pendingRemovalTag={pendingRemovalTag}
                  registerNode={registerNode}
                />
              );
            })
          )}
        </div>
      </div>
      <PreviewZoomOverlay
        open={Boolean(overlayDisplay?.url)}
        display={overlayDisplay}
        onClose={closeOverlay}
        originRect={overlayOriginRect}
        originTransform={overlayOriginTransform}
      />
    </>
  );
}

export default DesktopWorkspace;