refactoring, linting, formatting

src/pdf/pdfService.ts

@@ -1,10 +1,20 @@
-import { PDFDocument, degrees } from 'pdf-lib';
-import type { PdfFile, PageRef, SplitResult, Range } from './pdfTypes';
+import { PDFDocument, degrees } from "pdf-lib";
+import type { PdfFile, PageRef, SplitResult, Range } from "./pdfTypes";
 
 function createId() {
   return Math.random().toString(36).slice(2);
 }
 
+function pdfBytesToArrayBuffer(bytes: Uint8Array): ArrayBuffer {
+  const buffer = new ArrayBuffer(bytes.byteLength);
+  new Uint8Array(buffer).set(bytes);
+  return buffer;
+}
+
+function pdfBytesToBlob(bytes: Uint8Array): Blob {
+  return new Blob([pdfBytesToArrayBuffer(bytes)], { type: "application/pdf" });
+}
+
 export async function loadPdfFromFile(file: File): Promise<PdfFile> {
   const arrayBuffer = await file.arrayBuffer();
   const doc = await PDFDocument.load(arrayBuffer);
@@ -21,10 +31,10 @@ export async function loadPdfFromFile(file: File): Promise<PdfFile> {
 export async function mergePdfFiles(
   basePdf: PdfFile,
   newPdf: PdfFile,
-  insertAt: number
+  insertAt: number,
 ): Promise<PdfFile> {
-  const baseDoc = basePdf.doc ?? await PDFDocument.load(basePdf.arrayBuffer);
-  const newDoc = newPdf.doc ?? await PDFDocument.load(newPdf.arrayBuffer);
+  const baseDoc = basePdf.doc ?? (await PDFDocument.load(basePdf.arrayBuffer));
+  const newDoc = newPdf.doc ?? (await PDFDocument.load(newPdf.arrayBuffer));
 
   const mergedDoc = await PDFDocument.create();
 
@@ -35,11 +45,11 @@ export async function mergePdfFiles(
 
   const basePages = await mergedDoc.copyPages(
     baseDoc,
-    Array.from({ length: basePageCount }, (_, i) => i)
+    Array.from({ length: basePageCount }, (_, i) => i),
   );
   const newPages = await mergedDoc.copyPages(
     newDoc,
-    Array.from({ length: newPageCount }, (_, i) => i)
+    Array.from({ length: newPageCount }, (_, i) => i),
   );
 
   for (let i = 0; i < clampedInsertAt; i += 1) {
@@ -53,11 +63,10 @@ export async function mergePdfFiles(
   }
 
   const bytes = await mergedDoc.save();
-  const buffer = new ArrayBuffer(bytes.byteLength);
-  new Uint8Array(buffer).set(bytes);
+  const buffer = pdfBytesToArrayBuffer(bytes);
 
-  const baseName = basePdf.name.replace(/\.pdf$/i, '');
-  const newName = newPdf.name.replace(/\.pdf$/i, '');
+  const baseName = basePdf.name.replace(/\.pdf$/i, "");
+  const newName = newPdf.name.replace(/\.pdf$/i, "");
 
   return {
     id: createId(),
@@ -69,7 +78,7 @@ export async function mergePdfFiles(
 }
 
 export async function splitIntoSinglePages(
-  pdf: PdfFile
+  pdf: PdfFile,
 ): Promise<SplitResult[]> {
   const { doc, name } = pdf;
 
@@ -99,10 +108,10 @@ export async function splitIntoSinglePages(
     if (modificationDate) newDoc.setModificationDate(modificationDate);
 
     const bytes = await newDoc.save();
-    const blob = new Blob([bytes], { type: 'application/pdf' });
+    const blob = pdfBytesToBlob(bytes);
 
-    const base = name.replace(/\.pdf$/i, '');
-    const filename = `${base}_page_${String(i + 1).padStart(3, '0')}.pdf`;
+    const base = name.replace(/\.pdf$/i, "");
+    const filename = `${base}_page_${String(i + 1).padStart(3, "0")}.pdf`;
 
     results.push({
       pageIndex: i,
@@ -114,10 +123,7 @@ export async function splitIntoSinglePages(
   return results;
 }
 
-export async function extractRange(
-  pdf: PdfFile,
-  range: Range
-): Promise<Blob> {
+export async function extractRange(pdf: PdfFile, range: Range): Promise<Blob> {
   const { doc } = pdf;
   const pageCount = doc.getPageCount();
 
@@ -125,7 +131,7 @@ export async function extractRange(
   const toIndex = Math.min(pageCount - 1, range.to - 1);
 
   if (fromIndex > toIndex) {
-    throw new Error('Invalid range: from > to');
+    throw new Error("Invalid range: from > to");
   }
 
   const newDoc = await PDFDocument.create();
@@ -136,7 +142,7 @@ export async function extractRange(
   copiedPages.forEach((p) => newDoc.addPage(p));
 
   const bytes = await newDoc.save();
-  return new Blob([bytes], { type: 'application/pdf' });
+  return pdfBytesToBlob(bytes);
 }
 
 export async function mergePdfs(pdfs: PdfFile[]): Promise<Blob> {
@@ -150,26 +156,26 @@ export async function mergePdfs(pdfs: PdfFile[]): Promise<Blob> {
   }
 
   const bytes = await newDoc.save();
-  return new Blob([bytes], { type: 'application/pdf' });
+  return pdfBytesToBlob(bytes);
 }
 
 export async function exportPages(
   pdf: PdfFile,
-  pages: PageRef[]
+  pages: PageRef[],
 ): Promise<Blob> {
   const { doc } = pdf;
   const pageCount = doc.getPageCount();
 
   if (pages.length === 0) {
-    throw new Error('Pages must contain at least one page');
+    throw new Error("Pages must contain at least one page");
   }
 
   if (
     pages.some(
-      (page) => page.sourcePageIndex < 0 || page.sourcePageIndex >= pageCount
+      (page) => page.sourcePageIndex < 0 || page.sourcePageIndex >= pageCount,
     )
   ) {
-    throw new Error('Pages contain invalid source page indices');
+    throw new Error("Pages contain invalid source page indices");
   }
 
   const newDoc = await PDFDocument.create();
@@ -180,7 +186,7 @@ export async function exportPages(
   copiedPages.forEach((page, idx) => {
     const angle = pages[idx].rotation;
 
-    if (typeof angle === 'number' && angle % 360 !== 0) {
+    if (typeof angle === "number" && angle % 360 !== 0) {
       page.setRotation(degrees(angle));
     }
 
@@ -188,13 +194,13 @@ export async function exportPages(
   });
 
   const bytes = await newDoc.save();
-  return new Blob([bytes], { type: 'application/pdf' });
+  return pdfBytesToBlob(bytes);
 }
 
 export async function exportReordered(
   pdf: PdfFile,
   order: number[],
-  rotations?: Record<number, number>
+  rotations?: Record<number, number>,
 ): Promise<Blob> {
   return exportPages(
     pdf,
@@ -202,6 +208,6 @@ export async function exportReordered(
       id: String(sourcePageIndex),
       sourcePageIndex,
       rotation: rotations?.[sourcePageIndex] ?? 0,
-    }))
+    })),
   );
-}
+}