// generate_pdf.php
require_once('vendor/autoload.php');
require_once('barcode/BarcodeGenerator.php');
require_once('barcode/BarcodeGeneratorPNG.php');
require_once('config.php');  // Include the database configuration

use TCPDF;
use Picqer\Barcode\BarcodeGeneratorPNG;

// Input from form
$organization = $_POST['organization'];
$application = $_POST['application'];
$audit_type = $_POST['audit_type'];
$url = $_POST['url'];
$testing_date = $_POST['testing_date'];
$revalidation_date = $_POST['revalidation_date'];
$report_id = $_POST['report_id'];
$issued_on = $_POST['issued_on'];
$certificate_number = $_POST['certificate_number'];
$conclusion = $_POST['conclusion'];
$recommendations = $_POST['recommendations'];

// Generate a unique 128-length random key
$unique_key = bin2hex(random_bytes(64)); // 128 characters (64 bytes)

// Generate the barcode
$generator = new BarcodeGeneratorPNG();
$barcode = $generator->getBarcode($unique_key, BarcodeGeneratorPNG::TYPE_CODE_128);

// Insert the certificate details into the database
try {
    $stmt = $pdo->prepare("INSERT INTO certificates 
        (organization, application, audit_type, url, testing_date, revalidation_date, report_id, 
        issued_on, certificate_number, conclusion, recommendations, verification_key)
        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");

    $stmt->execute([
        $organization,
        $application,
        $audit_type,
        $url,
        $testing_date,
        $revalidation_date,
        $report_id,
        $issued_on,
        $certificate_number,
        $conclusion,
        $recommendations,
        $unique_key
    ]);
    
    // Get the last inserted certificate ID (if needed for other purposes)
    $certificate_id = $pdo->lastInsertId();

} catch (PDOException $e) {
    die("Error saving certificate to the database: " . $e->getMessage());
}

// Initialize TCPDF
$pdf = new TCPDF();
$pdf->AddPage();

// Set font
$pdf->SetFont('helvetica', '', 12);

// Add the certificate details to PDF
$pdf->Cell(0, 10, "Certificate of Audit", 0, 1, 'C');
$pdf->Ln(10);

$pdf->Cell(0, 10, "Organization: $organization", 0, 1);
$pdf->Cell(0, 10, "Application: $application", 0, 1);
$pdf->Cell(0, 10, "Type of Audit: $audit_type", 0, 1);
$pdf->Cell(0, 10, "URL: $url", 0, 1);
$pdf->Cell(0, 10, "Initial Testing Date: $testing_date", 0, 1);
$pdf->Cell(0, 10, "Revalidation Date: $revalidation_date", 0, 1);
$pdf->Cell(0, 10, "Report ID: $report_id", 0, 1);
$pdf->Cell(0, 10, "Issued On: $issued_on", 0, 1);
$pdf->Cell(0, 10, "Certificate Number: $certificate_number", 0, 1);
$pdf->Cell(0, 10, "Conclusion: $conclusion", 0, 1);
$pdf->Cell(0, 10, "Recommendations: $recommendations", 0, 1);

// Embed the 128-length random key in the PDF
$pdf->Cell(0, 10, "Verification Key: $unique_key", 0, 1);

// Output the barcode image to PDF
$pdf->Image('@' . $barcode, 160, 250, 40, 15);

// Save the PDF
$pdf->Output("certificate_$certificate_number.pdf", 'I'); // 'I' for inline display in browser