From d406d973823d91d05078f8c658801b7b72f1db66 Mon Sep 17 00:00:00 2001
From: Jim Graham <info@sparkmediagroup.com>
Date: Wed, 1 Dec 2021 00:20:42 -0500
Subject: [PATCH] Feature: Support Multi-Step Paged Forms

Adds ability to have multiple submit buttons/inputs. With this change (and a specific method of setup in the form templates), form data can be posted when navigating away from the current form step.
---
 .../formalicioussnippetrenderform.class.php   | 48 ++++++++++++++-----
 1 file changed, 36 insertions(+), 12 deletions(-)

diff --git a/core/components/formalicious/model/formalicious/snippets/formalicioussnippetrenderform.class.php b/core/components/formalicious/model/formalicious/snippets/formalicioussnippetrenderform.class.php
index efc293d..2f208fa 100644
--- a/core/components/formalicious/model/formalicious/snippets/formalicioussnippetrenderform.class.php
+++ b/core/components/formalicious/model/formalicious/snippets/formalicioussnippetrenderform.class.php
@@ -147,7 +147,7 @@ public function run(array $properties = [])
                     $hooks[] = 'FormaliciousHookHandleForm';
                 }
 
-                if ($currentStep >= $totalSteps) {
+                if ($currentStep >= $totalSteps && isset($_POST[$parameters['submitVar']])) {
                     if (!in_array('FormaliciousHookRemoveForm', $hooks, true)) {
                         $hooks[] = 'FormaliciousHookRemoveForm';
                     }
@@ -198,8 +198,30 @@ public function run(array $properties = [])
                 } else {
                     $hooks[] = 'redirect';
 
+                    /*
+                        Set up redirect in a way that allows variable/dynamic destination, based on
+                        value stored in the submit input/button. This way, form data on the step that is
+                        being navigated away from will always be posted/saved. Navigation and pagination
+                        should then be done via submit inputs/buttons instead of <a> tags.
+
+                        A related change to FormIt's Request class is necessary for this additional functionality.
+                    */
+
+                    # Default redirect destination
+                    $destination = $currentStep + 1;
+
+                    # Check for alternate destination request
+                    if ($_POST) {
+                        foreach ($_POST as $k => $v) {
+                            if (strpos($k, $parameters['submitVar']) !== false) {
+                                $destination = is_numeric($v) ? $v : $destination ;
+                                break;
+                            }
+                        }
+                    }
+
                     $parameters['redirectTo'] = $this->getStepUrl([
-                        $this->getProperty('stepParam') => $currentStep + 1
+                        $this->getProperty('stepParam') => (int)$destination
                     ], 'full');
 
                     if (empty($placeholders['submitTitle'])) {
@@ -226,21 +248,23 @@ public function run(array $properties = [])
                 $parameters['formaliciousTplNavigationItem'] = $this->getProperty('tplNavigationItem');
                 $parameters['formaliciousTplNavigationWrapper'] = $this->getProperty('tplNavigationWrapper');
 
-                if ($currentStep <= 1) {
-                    $placeholders['prevUrl'] = $this->getStepUrl();
-                } else {
+                if ($currentStep > 1) {
                     $placeholders['prevUrl'] = $this->getStepUrl([
                         $this->getProperty('stepParam') => $currentStep - 1
                     ]);
+                    $placeholders['submitValPrev'] = $currentStep - 1;
                 }
 
-                if ($totalSteps === 1) {
-                    $placeholders['currentUrl'] = $this->getStepUrl();
-                } else {
-                    $placeholders['currentUrl'] = $this->getStepUrl([
-                        $this->getProperty('stepParam') => $currentStep
-                    ]);
-                }
+                $placeholders['submitValLast'] = $totalSteps;
+
+                # Suggest renaming this placeholder, as it makes its purpose more immediately clear
+                $placeholders['formAction'] = $totalSteps === 1
+                    ? $this->getStepUrl()
+                    : $this->getStepUrl([$this->getProperty('stepParam') => $currentStep])
+                    ;
+
+                # Set orignal for backward compatibility
+                $placeholders['currentUrl'] = $placeholders['formAction'];
 
                 return $this->getChunk($this->getProperty('tplForm'), array_merge($placeholders, $parameters, [
                     'FormItParameters'      => $this->parseParameters($parameters),