Preserve QExcell frozen panes in XLSX

src/io/excellOffice.ts

@@ -1,4 +1,4 @@
-import type { CellFormat, MergedCellRange, SheetChart, SheetChartType, Workbook } from "../types";
+import type { CellFormat, MergedCellRange, SheetChart, SheetChartType, SheetFrozenPane, Workbook } from "../types";
 import { evaluateCell, expandRange } from "../utils/spreadsheet";
 import { officeTitleFromFileName, readOfficeFileAsArrayBuffer, XLSX_MIME_TYPE } from "./fileHelpers";
 
@@ -9,6 +9,7 @@ export interface ImportedExcellWorkbook {
     id: string;
     name: string;
     visibility?: "hidden" | "veryHidden";
+    frozenPane?: SheetFrozenPane;
     cells: Record<string, string>;
     mergedCells?: MergedCellRange[];
     hyperlinks?: Record<string, string>;
@@ -56,6 +57,7 @@ interface ParsedSheet {
   id: string;
   name: string;
   visibility?: "hidden" | "veryHidden";
+  frozenPane?: SheetFrozenPane;
   cells: Record<string, string>;
   mergedCells?: MergedCellRange[];
   hyperlinks?: Record<string, string>;
@@ -63,6 +65,13 @@ interface ParsedSheet {
   charts?: SheetChart[];
 }
 
+type NormalizedFrozenPane = {
+  columns: number;
+  rows: number;
+  topLeftCell: string;
+  activePane: NonNullable<SheetFrozenPane["activePane"]>;
+};
+
 interface WorksheetCellRecord {
   address: string;
   cell: XmlRecord;
@@ -245,7 +254,7 @@ export async function exportXlsxBlob(workbook: Workbook): Promise<Blob> {
     const drawingRelationshipId = sheetChartParts.length > 0 ? `rId${sortedExternalHyperlinkEntries(sheet.hyperlinks).length + 1}` : "";
     zip.file(
       `xl/worksheets/sheet${index + 1}.xml`,
-      buildWorksheetXml(sheet.cells, sheet.mergedCells, sheet.hyperlinks, sheet.cellFormats, styleRegistry, drawingRelationshipId)
+      buildWorksheetXml(sheet.cells, sheet.mergedCells, sheet.hyperlinks, sheet.cellFormats, styleRegistry, drawingRelationshipId, sheet.frozenPane)
     );
     const relationshipsXml = buildWorksheetRelationshipsXml(
       sheet.hyperlinks,
@@ -276,10 +285,13 @@ export function parsedWorksheetToSheet(
   relationshipsXml?: unknown,
   styleTable: Array<CellFormat | undefined> = []
 ): ParsedSheet {
+  const frozenPane = worksheetXmlToFrozenPane(worksheetXml);
+
   return {
     id: sheet.id || `sheet-${index + 1}`,
     name: sheet.name || `Лист ${index + 1}`,
     ...(sheet.visibility ? { visibility: sheet.visibility } : {}),
+    ...(frozenPane ? { frozenPane } : {}),
     cells: worksheetXmlToCells(worksheetXml, sharedStrings),
     mergedCells: worksheetXmlToMergedCells(worksheetXml),
     hyperlinks: worksheetXmlToHyperlinks(worksheetXml, relationshipsXml),
@@ -371,6 +383,33 @@ export function worksheetXmlToHyperlinks(worksheetXml: unknown, relationshipsXml
   }, {});
 }
 
+export function worksheetXmlToFrozenPane(worksheetXml: unknown): SheetFrozenPane | undefined {
+  const worksheet = childRecord(worksheetXml, "worksheet");
+  const sheetViews = childRecord(worksheet, "sheetViews");
+  const sheetView = asRecord(toArray(sheetViews.sheetView)[0]);
+  const pane = childRecord(sheetView, "pane");
+  const state = String(pane.state ?? "").trim().toLowerCase();
+  if (state !== "frozen" && state !== "frozensplit") {
+    return undefined;
+  }
+
+  const columns = paneSplitCount(pane.xSplit);
+  const rows = paneSplitCount(pane.ySplit);
+  if (columns === 0 && rows === 0) {
+    return undefined;
+  }
+
+  const topLeftCell = normalizeCellAddress(String(pane.topLeftCell ?? "")) || frozenPaneTopLeftCell(columns, rows);
+  const activePane = normalizedFrozenPaneActivePane(pane.activePane) || frozenPaneActivePane(columns, rows);
+
+  return {
+    ...(columns > 0 ? { columns } : {}),
+    ...(rows > 0 ? { rows } : {}),
+    topLeftCell,
+    activePane
+  };
+}
+
 async function worksheetXmlToCharts(
   zip: ZipInstance,
   parser: InstanceType<XmlParserConstructor>,
@@ -541,7 +580,8 @@ export function buildWorksheetXml(
   hyperlinks: Record<string, string> = {},
   cellFormats: Record<string, CellFormat> = {},
   styleRegistry = createCellStyleRegistry([cellFormats]),
-  drawingRelationshipId = ""
+  drawingRelationshipId = "",
+  frozenPane?: SheetFrozenPane
 ) {
   const rows = sortedWorksheetEntries(cells, cellFormats).reduce<Record<number, Array<[string, string]>>>((grouped, entry) => {
     const rowNumber = cellRowNumber(entry[0]);
@@ -562,9 +602,10 @@ export function buildWorksheetXml(
   const mergeCellsXml = buildMergeCellsXml(mergedCells);
   const hyperlinksXml = buildHyperlinksXml(hyperlinks);
   const drawingXml = drawingRelationshipId ? `<drawing r:id="${escapeXmlAttribute(drawingRelationshipId)}"/>` : "";
+  const sheetViewsXml = buildSheetViewsXml(frozenPane);
 
   return xmlDeclaration(
-    `<worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"><sheetData>${rowXml}</sheetData>${mergeCellsXml}${hyperlinksXml}${drawingXml}</worksheet>`
+    `<worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">${sheetViewsXml}<sheetData>${rowXml}</sheetData>${mergeCellsXml}${hyperlinksXml}${drawingXml}</worksheet>`
   );
 }
 
@@ -621,6 +662,25 @@ export function buildHyperlinksXml(hyperlinks: Record<string, string> = {}) {
   return `<hyperlinks>${hyperlinkXml}</hyperlinks>`;
 }
 
+export function buildSheetViewsXml(frozenPane?: SheetFrozenPane) {
+  const pane = normalizedFrozenPane(frozenPane);
+  if (!pane) {
+    return "";
+  }
+
+  const attributes = [
+    pane.columns > 0 ? `xSplit="${pane.columns}"` : "",
+    pane.rows > 0 ? `ySplit="${pane.rows}"` : "",
+    `topLeftCell="${escapeXmlAttribute(pane.topLeftCell)}"`,
+    `activePane="${pane.activePane}"`,
+    'state="frozen"'
+  ]
+    .filter(Boolean)
+    .join(" ");
+
+  return `<sheetViews><sheetView workbookViewId="0"><pane ${attributes}/></sheetView></sheetViews>`;
+}
+
 export function buildWorksheetRelationshipsXml(hyperlinks: Record<string, string> = {}, drawingTarget = "") {
   const refs = sortedExternalHyperlinkEntries(hyperlinks);
   if (refs.length === 0 && !drawingTarget) {
@@ -1305,6 +1365,45 @@ function numberAttribute(value: unknown) {
   return Number.isInteger(number) && number >= 0 ? number : 0;
 }
 
+function normalizedFrozenPane(pane?: SheetFrozenPane): NormalizedFrozenPane | null {
+  const columns = paneSplitCount(pane?.columns);
+  const rows = paneSplitCount(pane?.rows);
+  if (columns === 0 && rows === 0) {
+    return null;
+  }
+
+  const topLeftCell = normalizeCellAddress(pane?.topLeftCell ?? "") || frozenPaneTopLeftCell(columns, rows);
+  const activePane = normalizedFrozenPaneActivePane(pane?.activePane) || frozenPaneActivePane(columns, rows);
+
+  return {
+    columns,
+    rows,
+    topLeftCell,
+    activePane
+  };
+}
+
+function paneSplitCount(value: unknown) {
+  const number = Number(value);
+  return Number.isFinite(number) && number > 0 ? Math.floor(number) : 0;
+}
+
+function frozenPaneTopLeftCell(columns: number, rows: number) {
+  return cellAddress(columns + 1, rows + 1);
+}
+
+function frozenPaneActivePane(columns: number, rows: number): NormalizedFrozenPane["activePane"] {
+  if (columns > 0 && rows > 0) {
+    return "bottomRight";
+  }
+
+  return columns > 0 ? "topRight" : "bottomLeft";
+}
+
+function normalizedFrozenPaneActivePane(value: unknown): NormalizedFrozenPane["activePane"] | "" {
+  return value === "topRight" || value === "bottomLeft" || value === "bottomRight" ? value : "";
+}
+
 async function readSharedStrings(zip: ZipInstance, parser: InstanceType<XmlParserConstructor>) {
   const sharedStringsFile = zip.file("xl/sharedStrings.xml");
   if (!sharedStringsFile) {