What are the recommended steps for troubleshooting and resolving issues related to generating PDF previews using PHP, particularly when integrating with JavaScript libraries like cluetip for display purposes?

Issue: When generating PDF previews using PHP and integrating with JavaScript libraries like cluetip for display purposes, there may be issues with the generation process or displaying the preview correctly. Solution: To troubleshoot and resolve these issues, ensure that the PDF generation process in PHP is functioning correctly and that the generated PDF files are accessible to the JavaScript library for display. Check for any errors in the PDF generation code and make sure the cluetip library is properly configured to handle PDF previews. PHP Code Snippet:

// Sample PHP code for generating a PDF preview
$pdf_file = 'sample.pdf';

// Check if the PDF file exists
if (file_exists($pdf_file)) {
    // Output the PDF file for display
    header('Content-type: application/pdf');
    readfile($pdf_file);
} else {
    echo 'Error: PDF file not found';
}