Stamp a PDF in Mirth

stamp.js

var PDDocument = org.apache.pdfbox.pdmodel.PDDocument;
var PDPage = org.apache.pdfbox.pdmodel.PDPage;
var PDPageContentStream = org.apache.pdfbox.pdmodel.PDPageContentStream;
var PDType1Font = org.apache.pdfbox.pdmodel.font.PDType1Font;
var Standard14Fonts = org.apache.pdfbox.pdmodel.font.Standard14Fonts;
var PDImageXObject = org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;
var PDFTextStripper = org.apache.pdfbox.text.PDFTextStripper;
var TextPosition = org.apache.pdfbox.text.TextPosition;
var File = java.io.File;
var HashMap = java.util.HashMap;
var ArrayList = java.util.ArrayList;

/**
 * BoundingPoint - represents a point in 2D space
 */
function BoundingPoint(x, y) {
    this.x = x;
    this.y = y;
}

/**
 * BoundingBox - represents a rectangular area with type information
 */
function BoundingBox(type, bottomLeft, topRight) {
    this.type = type;
    
    // Determine the actual bottom-left and top-right coordinates
    var actualBottomLeftX = Math.min(bottomLeft.x, topRight.x);
    var actualBottomLeftY = Math.min(bottomLeft.y, topRight.y);
    var actualTopRightX = Math.max(bottomLeft.x, topRight.x);
    var actualTopRightY = Math.max(bottomLeft.y, topRight.y);
    
    this.x = actualBottomLeftX;
    this.y = actualBottomLeftY;
    this.width = actualTopRightX - actualBottomLeftX;
    this.height = actualTopRightY - actualBottomLeftY;
}

/**
 * TextLocationStripper - extends PDFTextStripper to find markers in PDF text
 */
function TextLocationStripper() {
    var symbols = ["s<", "i<", ">s", ">i"];
    var unmatchedPoints = new HashMap();
    var boundingRects = [];
    return new JavaAdapter(PDFTextStripper, {
        boundingRects: boundingRects,
        writeString: function(string, textPositions) {
            string = String(string);
            if (string.length === 2 && symbols.indexOf(string) !== -1) {
                var marker = string.replace("<", "").replace(">", "");
                var pos = textPositions.get(0);
                var newPoint = new BoundingPoint(pos.getX(), pos.getPageHeight() - pos.getY());
                var unmatched = unmatchedPoints.remove(marker);
                
                if (unmatched == null) {
                    unmatchedPoints.put(marker, newPoint);
                } else {
                    this.boundingRects.push(new BoundingBox(marker, unmatched, newPoint));
                }
            }
        }
    });
}

/**
 * Find bounding boxes on a specific page
 */
function findBoundingBoxesOnPage(document, pageIndex) {
    var stripper = new TextLocationStripper();
    stripper.setStartPage(pageIndex + 1);
    stripper.setEndPage(pageIndex + 1);
    var text = stripper.getText(document);
    return stripper.boundingRects;
}

/**
 * Main stamping function - equivalent to the Java stampPdf method
 * 
 * @param {string} inputPdfPath - Path to input PDF file
 * @param {string} signatureImagePath - Path to signature image file
 * @param {string} metadataText - Metadata text to stamp (semicolon-separated)
 * @param {string} outputPdfPath - Path for output PDF file
 */
function stampPdf(inputPdfPath, signatureImagePath, metadataText, outputPdfPath) {
    var document = PDDocument.load(new File(inputPdfPath));
    try {
        //logger.info("Loaded PDF with " + document.getNumberOfPages() + " pages");
        var signatureImage = PDImageXObject.createFromFile(signatureImagePath, document);
        
        for (var pageIndex = 0; pageIndex < document.getNumberOfPages(); pageIndex++) {
            var page = document.getPage(pageIndex);
            var boxes = findBoundingBoxesOnPage(document, pageIndex);
            
            var contentStream = new PDPageContentStream(document, page, PDPageContentStream.AppendMode.APPEND, true, true);
            try {
                for (var i = 0; i < boxes.length; i++) {
                    var box = boxes[i];
                    if ("i" === box.type) {
                        contentStream.beginText();
                        contentStream.setFont(PDType1Font.HELVETICA, 8.0);
                        contentStream.newLineAtOffset(box.x, box.y);
                        contentStream.showText('Hello World');
                        contentStream.endText();
                    }
                }
            } finally {
                contentStream.close();
            }
        }
        
        document.save(outputPdfPath);
    } finally {
        document.close();
    }
}