Easy Digital Downloads - Frontend Submissions - Pay To Upload. Forces the vendor to pay for each file uploaded before the product is published

gistfile1.php

<?php
/**
 * Plugin Name: Easy Digital Downloads - Frontend Submissions - Pay To Upload
 * Plugin URI: 
 * Description: Forces the vendor to pay for each file uploaded before the product is published
 * Author: Andrew Munro
 * Author URI: http://sumobi.com
 * Version: 1.0
 */

/**
 * @todo Allow the vendor upload more files when editing the product and pay the additional cost
 * @todo Provide an input in the EDD settings for entering the amount a vendor should pay per file upload
 * @todo Provide a live count of how much the vendor needs to pay as each file upload field is populated on the submission form
 */

/**
 * Get the amount to charge for each uploaded file
 *
 * @since 1.0
 */
function edd_fes_ptu_get_amount() {
	$amount = 5;

	return $amount;
}

/**
 * Check if the files for a download have been paid for
 *
 * @since 1.0
 */
function edd_fes_ptu_has_paid( $download_id = 0 ) {
	
	if ( ! $download_id ) {
		return;
	}

	$has_paid = get_post_meta( $download_id, 'edd_fes_fee_paid', true );

	if ( $has_paid ) {
		return (boolean) true;
	}

	return (boolean) false;
}

/**
 * Tell the vendor how much each file is going to cost
 *
 * @since 1.0
 */
function edd_fes_ptu_show_message( $form_vars, $id, $type, $form_id, $read_only, $args ) {
	ob_start(); 
?>

	<div class="fes-label">
		<p>Each uploaded file costs <?php echo edd_currency_filter( edd_format_amount( edd_fes_ptu_get_amount() ) ); ?>. After submitting your product you will be redirected to the checkout for payment.</p>
	</div>

	<?php
	$html = ob_get_clean();

	echo $html;
}
add_action( 'fes_before_file_upload_output', 'edd_fes_ptu_show_message', 10, 6 );

/**
 * Add fee and redirect vendor for payment
 *
 * @since 1.0
 */
function edd_fes_ptu_vendor_submission_redirect( $response, $post_id, $form_id ) {

	// file uploads for this download have already been paid for
	if ( edd_fes_ptu_has_paid( $post_id ) ) {
		return $response;
	}

	// get amount per file
	$amount_per_file = 5;

	$file_count = array_filter( $_POST['file_upload'] );
	$file_count = count( $file_count );

	$fee_amount = $file_count * $amount_per_file;
	$fee_label  = 'File Upload Fees';

	// add fee
	EDD()->fees->add_fee( 
		array( 
			'amount' => $fee_amount, 
			'type'   => 'item', 
			'id'     => 'file_upload_fees', 
			'label'  => $fee_label
		)
	);

	// store the download ID in EDD session, we'll need to retrieve it after payment
	EDD()->session->set( 'edd_fes_download_post_id', $post_id );

	// store how many fields they are paying for so we can store in post meta later on
	EDD()->session->set( 'edd_fes_file_count', $file_count );

	// redirect to checkout for payment
	$response['redirect_to'] = edd_get_checkout_uri();
	$response['message']     = 'Success! Redirecting to checkout for payment';

	return $response;

}
add_filter( 'fes_add_post_redirect', 'edd_fes_ptu_vendor_submission_redirect', 10, 3 );


/**
 * Set download to pending status until they have paid
 *
 * @since 1.0
 */
function edd_fes_ptu_submit_product( $postarr, $form_id, $form_settings, $form_vars ) {

	// set the download to pending until payment has been made
	$postarr['post_status'] = 'pending';

	return $postarr;

}
add_filter( 'fes_add_post_args', 'edd_fes_ptu_submit_product', 10, 4 );


/**
 * Vendor has paid, make product live
 *
 * @since 1.0
 */
function edd_fes_ptu_vendor_paid( $payment_id ) {

	if ( ! EDD()->session->get( 'edd_fes_download_post_id' ) ) {
		return;
	}

	$download_id = EDD()->session->get( 'edd_fes_download_post_id' );

	// get the download ID and update post to publish
	$args = array(
		'ID'          => $download_id,
		'post_status' => 'publish' 
	);

	wp_update_post( $args );

	// mark download as being paid
	update_post_meta( $download_id, 'edd_fes_fee_paid', true );

	// how many were paid for? This determines the maximum number of fields they can ever have
	update_post_meta( $download_id, 'edd_fes_file_count', EDD()->session->get( 'edd_fes_file_count' ) ); 

}
add_action( 'edd_complete_purchase', 'edd_fes_ptu_vendor_paid' );


/**
 * Redirect vendor to products page on vendor dashboard
 * 
 * @since 1.0
 */
function edd_fes_ptu_redirect_to_dashboard() {

	if ( ! EDD()->session->get( 'edd_fes_download_post_id' ) ) {
		return;
	}

	return add_query_arg( 'task', 'products', get_permalink( EDD_FES()->helper->get_option( 'fes-vendor-dashboard-page', false ) ) );
	
}
add_filter( 'edd_get_success_page_uri', 'edd_fes_ptu_redirect_to_dashboard' );