Initial QOffice implementation

src/io/fileHelpers.ts

@@ -0,0 +1,52 @@
+export const DOCX_MIME_TYPE = "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
+export const XLSX_MIME_TYPE = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
+export const PPTX_MIME_TYPE = "application/vnd.openxmlformats-officedocument.presentationml.presentation";
+export const EML_MIME_TYPE = "message/rfc822;charset=utf-8";
+
+const pathSeparatorPattern = /[/\\]/;
+
+export function officeTitleFromFileName(fileName: string, fallbackTitle: string) {
+  const trimmed = fileName.trim();
+  if (!trimmed) {
+    return fallbackTitle;
+  }
+
+  const parts = trimmed.split(pathSeparatorPattern).filter(Boolean);
+  return parts[parts.length - 1] ?? fallbackTitle;
+}
+
+export function replaceFileExtension(fileName: string, extension: string) {
+  const normalizedExtension = extension.startsWith(".") ? extension : `.${extension}`;
+  const baseName = fileName.trim() || "Документ";
+  const withoutExtension = baseName.replace(/\.[^.\\/]+$/, "");
+
+  return `${withoutExtension}${normalizedExtension}`;
+}
+
+export async function readOfficeFileAsArrayBuffer(file: File) {
+  if (typeof file.arrayBuffer !== "function") {
+    return readFileWithFileReader(file);
+  }
+
+  return file.arrayBuffer();
+}
+
+function readFileWithFileReader(file: File): Promise<ArrayBuffer> {
+  if (typeof FileReader === "undefined") {
+    throw new Error("Не удалось прочитать файл: среда не поддерживает File.arrayBuffer() и FileReader.");
+  }
+
+  return new Promise((resolve, reject) => {
+    const reader = new FileReader();
+    reader.onerror = () => reject(new Error("Не удалось прочитать файл."));
+    reader.onload = () => {
+      if (reader.result instanceof ArrayBuffer) {
+        resolve(reader.result);
+        return;
+      }
+
+      reject(new Error("Не удалось прочитать файл как ArrayBuffer."));
+    };
+    reader.readAsArrayBuffer(file);
+  });
+}