PKPFileUploadWizardHandler::uploadFile PHP Method

    function uploadFile($args, $request)
    {
        // Instantiate the file upload form.
        $submission = $this->getSubmission();
        import('lib.pkp.controllers.wizard.fileUpload.form.SubmissionFilesUploadForm');
        $uploadForm = new SubmissionFilesUploadForm($request, $submission->getId(), $this->getStageId(), null, null, $this->getFileStage(), $this->getRevisionOnly(), $this->getReviewRound(), null, $this->getAssocType(), $this->getAssocId());
        $uploadForm->readInputData();
        // Validate the form and upload the file.
        if (!$uploadForm->validate($request)) {
            return new JSONMessage(false, array_pop($uploadForm->getErrorsArray()));
        }
        $uploadedFile = $uploadForm->execute($request);
        /* @var $uploadedFile SubmissionFile */
        if (!is_a($uploadedFile, 'SubmissionFile')) {
            return new JSONMessage(false, __('common.uploadFailed'));
        }
        $this->_attachEntities($uploadedFile);
        // Retrieve file info to be used in a JSON response.
        $uploadedFileInfo = $this->_getUploadedFileInfo($uploadedFile);
        $reviewRound = $this->getReviewRound();
        // If no revised file id was given then try out whether
        // the user maybe accidentally didn't identify this file as a revision.
        if (!$uploadForm->getRevisedFileId()) {
            $revisedFileId = $this->_checkForRevision($uploadedFile, $uploadForm->getSubmissionFiles());
            if ($revisedFileId) {
                // Instantiate the revision confirmation form.
                import('lib.pkp.controllers.wizard.fileUpload.form.SubmissionFilesUploadConfirmationForm');
                $confirmationForm = new SubmissionFilesUploadConfirmationForm($request, $submission->getId(), $this->getStageId(), $this->getFileStage(), $reviewRound, $revisedFileId, $this->getAssocType(), $this->getAssocId(), $uploadedFile);
                $confirmationForm->initData($args, $request);
                // Render the revision confirmation form.
                return new JSONMessage(true, $confirmationForm->fetch($request), '0', $uploadedFileInfo);
            }
        }
        // Advance to the next step (i.e. meta-data editing).
        return new JSONMessage(true, '', '0', $uploadedFileInfo);
    }