Two file upload handler functions

front-end-uploads.php

	/**
	 * File upload ajax handler function to save the file and send image or file html back to the browser
         * These functions are part of a class
	 */
	function ajax_upload_file() {
		check_ajax_referer( 'ugc_user_upload', 'nonce' );
		$file_data = array(
			'name'     => $_FILES['ugc_attachment_file']['name'],
			'type'     => $_FILES['ugc_attachment_file']['type'],
			'tmp_name' => $_FILES['ugc_attachment_file']['tmp_name'],
			'error'    => $_FILES['ugc_attachment_file']['error'],
			'size'     => $_FILES['ugc_attachment_file']['size'],
		);

		$attachment_id = self::ugc_handle_upload( $file_data );

		if ( $attachment_id ) {
			$html = self::get_front_side_html( $attachment_id, $file_data );
			$response = array(
				'success' => true,
				'html'  => $html,
			);
			echo json_encode( $response );
			exit;

		} else {

			$response = array(
				'success' => false,
				'html'  => $file_data['error'],
			);

			echo json_encode( $response );
			exit;
		}
	}

	/**
	 * @param string $attachment_id
	 * @param array $file_data
	 *
	 * @return string
	 */
	function get_front_side_html( $attachment_id = '', $file_data = array() ) {

		$type = explode( '/', $file_data['type'] );

		if ( 'image' == $type[0] ) {
			$image = wp_get_attachment_image_src( $attachment_id, 'entry-image' );
			$url = $image[0];
		}

		elseif ( 'video' == $type[0] )
			$url = includes_url( '/images/crystal/video.png' );

		elseif ( 'audio' == $type[0] )
			$url = includes_url( '/images/crystal/audio.png' );

		else
			$url = includes_url( '/images/crystal/default.png' );

		$html  = sprintf( '<div class="ugc-item_upload" id="attachment-%d">', $attachment_id );
		$html .= sprintf( '<img src="%s" alt="%s" class="attachment-entry-image wp-post-image"/>', esc_url( $url ), esc_attr( $file_data['name'] ) );
		$html .= sprintf( '<p><span><strong>File name: </strong> %1$s </span><br><span><strong>File type: </strong>%2$s </span><br><span><strong>File size:</strong> %3$s</span></p>', esc_html( $file_data['name']), esc_html( $file_data['type']), esc_html( self::format_bytes( $file_data['size'] ) ) );
		$html .= sprintf( '<input type="hidden" name="ugc_featured_img" value="%s" />', $attachment_id );
		$html .= '</div>';

		return $html;

	}

        /**
         * This just inserts the attachment and forces use of a temp directory
         * @param array $file_data array extracted from $_FILES on upload
         * @param int $parent The post id to attach file to
         * @return mixed false on error or the attachment ID on success
         */
	function ugc_handle_upload( $file_data, $parent = 0 ) {

		$filter = new UGC_Attachment();

		add_filter( 'upload_dir', array( $filter, 'upload_dir_filter' ) );

		$file = wp_handle_upload( $file_data, array( 'test_form' => false ) );

		if ( isset($file['file'] ) ) {
			$location = $file['file'];  //File directory location
			$filename = basename( $file['file']);
			$filetype = wp_check_filetype( $filename );

			$attachment = array(
				'post_mime_type' => $filetype['type'],
				'post_title'     => preg_replace( '/\.[^.]+$/', '', basename( $filename ) ),
				'post_content'   => '',
				'post_status'    => 'inherit',
			);

			$attachment_id = wp_insert_attachment( $attachment, $location, $parent );
			require_once( ABSPATH . 'wp-admin/includes/image.php' );
			$file_meta = wp_generate_attachment_metadata( $attachment_id, $location );
			wp_update_attachment_metadata( $attachment_id, $file_meta );
			remove_filter( 'upload_dir', array( $filter, 'upload_dir_filter' ) );

			return $attachment_id;
		}

		remove_filter( 'upload_dir', array( $filter, 'upload_dir_filter' ) );

		return false;
	}