MVP - Scale Pages, Scale Content

public/functions/scaleContent.js

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+const { PDFDocument, ParseSpeeds } = PDFLib;
+
+export const scaleContent = async (snapshot, scale_factor) => {
+    // Load the original PDF file
+    const pdfDoc = await PDFDocument.load(snapshot, {
+        parseSpeed: ParseSpeeds.Fastest,
+    });
+
+    const pages = pdfDoc.getPages();
+
+    pages.forEach(page => {
+        const width = page.getWidth();
+        const height = page.getHeight();
+        
+        // Scale content
+        page.scaleContent(scale_factor, scale_factor);
+        const scaled_diff = {
+            width: Math.round(width - scale_factor * width),
+            height: Math.round(height - scale_factor * height),
+        };
+
+        // Center content in new page format
+        page.translateContent(Math.round(scaled_diff.width / 2), Math.round(scaled_diff.height / 2));
+
+    });
+
+    // Serialize the modified document
+    return pdfDoc.save();
+};

public/functions/scalePage.js

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+const { PDFDocument, ParseSpeeds } = PDFLib;
+
+export const scalePage = async (snapshot, page_size) => {
+    // Load the original PDF file
+    const pdfDoc = await PDFDocument.load(snapshot, {
+        parseSpeed: ParseSpeeds.Fastest,
+    });
+
+    const new_size = page_size;
+
+    const pages = pdfDoc.getPages();
+
+    pages.forEach(page => {
+        // Change page size
+        page.setSize(new_size.width, new_size.height);
+    });
+
+    // Serialize the modified document
+    return pdfDoc.save();
+};
+
+export const PageSize = {
+    a4: {
+        width: 594.96,
+        height: 841.92
+    },
+    letter: {
+        width: 612,
+        height: 792
+    }
+};