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<?php
/**
 * GP Unique ID // Gravity Perks // Reset Shortcode
 *
 * Provides a shortcode that generates a link that will reset the sequence of the specified Unique ID field.
 *
 * @version	  1.0
 * @author    David Smith <david@gravitywiz.com>
 * @license   GPL-2.0+
 * @link      http://gravitywiz.com/...
 * @copyright 2016 Gravity Wiz
 *
 * Plugin Name: GP Unique ID - Reset Shortcode
 * Plugin URI:  http://gravitywiz.com
 * Description: Provides a shortcode that generates a link that will reset the sequence of the specified Unique ID field.
 * Author:      David Smith
 * Version:     1.0
 * Author URI:  http://gravitywiz.com
 */
class GW_Reset_Shortcode {

    private static $instance = null;

    public static function get_instance() {
        if( self::$instance == null ) {
            self::$instance = new self;
        }
        return self::$instance;
    }

    private function __construct() {

        add_action( 'init', array( $this, 'init' ), 11 );

    }

    public function init() {

	    // make sure GF and GP Unique ID are running
	    if( ! class_exists( 'GFForms' ) || ! is_callable( 'gp_unique_id' ) ) {
		    return;
	    }

	    $this->parse_request();

	    add_shortcode( 'gpui_reset', array( $this, 'shortcode' ) );

    }

	public function parse_request() {

		if( ! rgget( 'gpui' ) || rgget( 'action' ) != 'reset' || isset( $_GET['result'] ) ) {
			return;
		}

		$form_id  = rgget( 'form_id' );
		$field_id = rgget( 'field_id' );
		$number   = rgget( 'number' ) ? rgget( 'number' ) : 0;

		$result = gp_unique_id()->set_sequential_starting_number( $form_id, $field_id, $number );

		wp_redirect( add_query_arg(
			array( 'result' => $result || $result === 0 ),
			remove_query_arg( array( 'form_id', 'field_id' ) )
		) );

		exit;

	}

	public function shortcode( $atts, $content = '' ) {

		$atts = shortcode_atts( array(
			'form'    => false,
			'field'   => false,
			'number'  => 0,
			'success' => __( 'Reset Successful!' ),
			'error'   => __( 'Reset Failed.' )
		), $atts, 'gpui_reset' );

		if( ! $atts['form'] || ! $atts['field'] ) {
			$content = 'Error: Missing a "form" or "field" parameter on the shortcode.';
		} else if( $this->get_reset_result() !== null ) {
			$content = $this->get_reset_result() ? $atts['success'] : $atts['error'];
		} else {
			$text    = ! empty( $content ) ? $content : __( 'Reset Sequence' );
			$url     = add_query_arg( array( 'gpui' => 1, 'action' => 'reset', 'form_id' => $atts['form'], 'field_id' => $atts['field'], 'number' => $atts['number'] ) );
			$content = sprintf( '<a href="%s">%s</a>', $url, $text );
		}

		return $content;
	}

	public function get_reset_result() {

		$result = null;

		if( rgget( 'gpui' ) && rgget( 'action' ) == 'reset' && isset( $_GET['result'] ) ) {
			$result = rgget( 'result' );
		}

		return $result;
	}

}

function gw_reset_shortcode() {
    return GW_Reset_Shortcode::get_instance();
}

gw_reset_shortcode();