/**
* Merge PDF files together in the order they were entered to the $files array.
*
* @return string|bool
* @see http://stackoverflow.com/questions/19855712/merge-multiple-pdf-files-into-one-in-php#answer-19856524
* @uses FPDI_Protection::setSourceFile()
* @uses FPDI_Protection::importPage()
* @uses FPDI_Protection::addPage()
* @uses FPDI_Protection::useTemplate()
* @uses FPDI_Protection::SetAuthor()
* @uses FPDI_Protection::SetCreator()
* @uses FPDI_Protection::SetTitle()
* @uses FPDI_Protection::SetSubject()
* @uses FPDI_Protection::SetKeywords()
* @uses FPDI_Protection::Output()
*/
public function merge()
{
$this->Log->write(__METHOD__, Log::LOG_LEVEL_SYSTEM_INFORMATION);
// input validation
if (!Helpers::is_array_ne($this->files)) {
$this->Log->write('Files is not an array. Enter at least 1 file before attempting to combine.', Log::LOG_LEVEL_WARNING);
return false;
}
try {
$pdf = new \FPDI_Protection();
foreach ($this->files as $file) {
$page_count = $pdf->setSourceFile($this->directory . $file);
for ($j = 0; $j < $page_count; $j++) {
$template_index = $pdf->importPage($j + 1, '/MediaBox');
$pdf->addPage($this->orientation, $this->paper_size);
$pdf->useTemplate($template_index, 0, 0, 0, 0, true);
}
// CAUTION: Delete the PDF input file if not debugging.
if (!$this->debug) {
unlink($file);
}
}
$pdf->SetAuthor($this->author);
$pdf->SetCreator($this->creator);
$pdf->SetTitle($this->title);
$pdf->SetSubject($this->subject);
$pdf->SetKeywords(implode(', ', $this->keywords));
if (Helpers::is_string_ne($this->user_password)) {
$pdf->SetProtection(array('print', 'copy'), $this->user_password, $this->owner_password);
}
$output_path = $this->directory . $this->output_file;
$this->Log->write('output file path', Log::LOG_LEVEL_USER, $output_path);
$output = $pdf->Output('F', $output_path);
if ($output === '') {
// file was created
return $output_path;
} else {
$this->Log->write('Error writing file to output', Log::LOG_LEVEL_WARNING, $output);
return $output;
}
} catch (\Exception $ex) {
$this->Log->exception($ex);
return false;
}
}
