feat: implement Phase 1A native WordPress event form system

✅ HVAC_Event_Form_Builder Implementation:
- Native WordPress event form builder extending HVAC_Form_Builder
- Complete datetime field types (start/end dates, timezone, all-day)
- Comprehensive venue field group (name, address, capacity, coordinates)
- Organizer field group (name, email, phone, website) with validation
- HVAC-specific fields (trainer requirements, certifications, equipment)
- Featured image upload support with security validation
- WordPress-native security integration (nonces, sanitization)
- Comprehensive form validation and error handling

🏗️ Architecture Improvements:
- Extract HVAC_Singleton_Trait to standalone file for better organization
- Add proper file loading order in HVAC_Plugin class
- Include core security framework and form builder dependencies

🧪 Testing Infrastructure:
- Native event test template for Phase 1A validation
- Staging deployment and testing completed successfully
- All form fields render and validate correctly

🎯 Strategic Progress:
- Phase 1A complete: Native form foundation established
- Eliminates dependency on problematic TEC Community Events forms
- Provides foundation for Phase 1B tribe_events post creation

🤖 Generated with Claude Code

Co-Authored-By: Claude <noreply@anthropic.com>

includes/class-hvac-event-form-builder.php

@@ -0,0 +1,680 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * HVAC Event Form Builder
+ *
+ * Extended form builder for native WordPress event management
+ * Replaces TEC Community Events forms with comprehensive field control
+ *
+ * @package    HVAC_Community_Events
+ * @subpackage Includes
+ * @since      3.0.0
+ */
+
+if (!defined('ABSPATH')) {
+    exit;
+}
+
+/**
+ * Class HVAC_Event_Form_Builder
+ *
+ * Extends HVAC_Form_Builder with event-specific field types and functionality
+ */
+class HVAC_Event_Form_Builder extends HVAC_Form_Builder {
+
+    /**
+     * Event-specific field defaults
+     *
+     * @var array
+     */
+    private array $event_field_defaults = [
+        'datetime-local' => [
+            'type' => 'datetime-local',
+            'class' => 'hvac-datetime-field',
+            'validate' => ['datetime'],
+            'sanitize' => 'datetime',
+        ],
+        'venue-group' => [
+            'type' => 'venue-group',
+            'class' => 'hvac-venue-group',
+            'wrapper_class' => 'form-group venue-group',
+        ],
+        'organizer-group' => [
+            'type' => 'organizer-group',
+            'class' => 'hvac-organizer-group',
+            'wrapper_class' => 'form-group organizer-group',
+        ],
+    ];
+
+    /**
+     * WordPress timezone list for event timezone selection
+     *
+     * @var array|null
+     */
+    private ?array $timezone_list = null;
+
+    /**
+     * Constructor with promoted property.
+     *
+     * @param string $nonce_action Nonce action for the form
+     */
+    public function __construct(string $nonce_action = 'hvac_event_form') {
+        parent::__construct($nonce_action);
+        $this->init_event_specific_features();
+    }
+
+    /**
+     * Initialize event-specific features
+     */
+    private function init_event_specific_features(): void {
+        // Set form enctype for file uploads (featured images)
+        $this->set_attributes(['enctype' => 'multipart/form-data']);
+
+        // Load timezone list
+        $this->timezone_list = $this->get_wordpress_timezones();
+    }
+
+    /**
+     * Add event datetime field
+     *
+     * @param array $field_config Field configuration
+     * @return self
+     */
+    public function add_datetime_field(array $field_config): self {
+        $defaults = array_merge($this->event_field_defaults['datetime-local'], [
+            'required' => true,
+            'description' => 'Select date and time for the event',
+        ]);
+
+        $field = wp_parse_args($field_config, $defaults);
+
+        // Ensure proper ID and name
+        if (empty($field['id']) && !empty($field['name'])) {
+            $field['id'] = sanitize_html_class($field['name']);
+        }
+
+        return $this->add_field($field);
+    }
+
+    /**
+     * Add event timezone selection field
+     *
+     * @param array $field_config Field configuration
+     * @return self
+     */
+    public function add_timezone_field(array $field_config = []): self {
+        $defaults = [
+            'type' => 'select',
+            'name' => 'event_timezone',
+            'label' => 'Event Timezone',
+            'options' => $this->timezone_list ?? [],
+            'value' => wp_timezone_string(),
+            'required' => true,
+            'class' => 'hvac-timezone-field',
+            'description' => 'Select the timezone for this event',
+        ];
+
+        $field = wp_parse_args($field_config, $defaults);
+        return $this->add_field($field);
+    }
+
+    /**
+     * Add all-day event toggle
+     *
+     * @param array $field_config Field configuration
+     * @return self
+     */
+    public function add_all_day_field(array $field_config = []): self {
+        $defaults = [
+            'type' => 'checkbox',
+            'name' => 'event_all_day',
+            'label' => 'All Day Event',
+            'value' => '1',
+            'class' => 'hvac-all-day-field',
+            'description' => 'Check if this is an all-day event',
+        ];
+
+        $field = wp_parse_args($field_config, $defaults);
+        return $this->add_field($field);
+    }
+
+    /**
+     * Add venue field group
+     *
+     * @param array $field_config Field configuration
+     * @return self
+     */
+    public function add_venue_group(array $field_config = []): self {
+        $venue_fields = [
+            [
+                'type' => 'text',
+                'name' => 'venue_name',
+                'label' => 'Venue Name',
+                'required' => true,
+                'class' => 'hvac-venue-name',
+                'placeholder' => 'Enter venue name',
+            ],
+            [
+                'type' => 'textarea',
+                'name' => 'venue_address',
+                'label' => 'Address',
+                'required' => false,
+                'class' => 'hvac-venue-address',
+                'placeholder' => 'Street address',
+                'validate' => ['max_length' => 500],
+            ],
+            [
+                'type' => 'text',
+                'name' => 'venue_city',
+                'label' => 'City',
+                'required' => false,
+                'class' => 'hvac-venue-city',
+            ],
+            [
+                'type' => 'text',
+                'name' => 'venue_state',
+                'label' => 'State/Province',
+                'required' => false,
+                'class' => 'hvac-venue-state',
+            ],
+            [
+                'type' => 'text',
+                'name' => 'venue_zip',
+                'label' => 'Postal Code',
+                'required' => false,
+                'class' => 'hvac-venue-zip',
+                'validate' => ['pattern' => '/^[A-Za-z0-9\s\-]{3,10}$/'],
+            ],
+            [
+                'type' => 'number',
+                'name' => 'venue_capacity',
+                'label' => 'Venue Capacity',
+                'required' => false,
+                'class' => 'hvac-venue-capacity',
+                'validate' => ['min' => 1, 'max' => 10000],
+                'description' => 'Maximum number of attendees (optional)',
+            ],
+            [
+                'type' => 'hidden',
+                'name' => 'venue_latitude',
+                'class' => 'hvac-venue-lat',
+            ],
+            [
+                'type' => 'hidden',
+                'name' => 'venue_longitude',
+                'class' => 'hvac-venue-lng',
+            ],
+        ];
+
+        // Add all venue fields
+        foreach ($venue_fields as $field) {
+            $this->add_field($field);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Add organizer field group
+     *
+     * @param array $field_config Field configuration
+     * @return self
+     */
+    public function add_organizer_group(array $field_config = []): self {
+        $organizer_fields = [
+            [
+                'type' => 'text',
+                'name' => 'organizer_name',
+                'label' => 'Organizer Name',
+                'required' => true,
+                'class' => 'hvac-organizer-name',
+                'placeholder' => 'Event organizer name',
+            ],
+            [
+                'type' => 'email',
+                'name' => 'organizer_email',
+                'label' => 'Organizer Email',
+                'required' => false,
+                'class' => 'hvac-organizer-email',
+                'validate' => ['email'],
+                'sanitize' => 'email',
+            ],
+            [
+                'type' => 'tel',
+                'name' => 'organizer_phone',
+                'label' => 'Organizer Phone',
+                'required' => false,
+                'class' => 'hvac-organizer-phone',
+                'validate' => ['pattern' => '/^[\+]?[1-9][\d]{0,15}$/'],
+            ],
+            [
+                'type' => 'url',
+                'name' => 'organizer_website',
+                'label' => 'Organizer Website',
+                'required' => false,
+                'class' => 'hvac-organizer-website',
+                'validate' => ['url'],
+                'sanitize' => 'url',
+                'placeholder' => 'https://example.com',
+            ],
+        ];
+
+        // Add all organizer fields
+        foreach ($organizer_fields as $field) {
+            $this->add_field($field);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Add HVAC-specific event fields
+     *
+     * @return self
+     */
+    public function add_hvac_fields(): self {
+        $hvac_fields = [
+            [
+                'type' => 'select',
+                'name' => 'trainer_requirements',
+                'label' => 'Trainer Requirements',
+                'options' => $this->get_trainer_requirement_options(),
+                'required' => false,
+                'class' => 'hvac-trainer-requirements',
+                'description' => 'What type of trainer is required for this event?',
+            ],
+            [
+                'type' => 'checkbox',
+                'name' => 'certification_levels',
+                'label' => 'Certification Levels',
+                'options' => $this->get_certification_level_options(),
+                'required' => false,
+                'class' => 'hvac-certification-levels',
+                'description' => 'Which certification levels does this event support?',
+            ],
+            [
+                'type' => 'textarea',
+                'name' => 'equipment_needed',
+                'label' => 'Equipment Needed',
+                'required' => false,
+                'class' => 'hvac-equipment-needed',
+                'placeholder' => 'List any specific equipment attendees should bring',
+                'validate' => ['max_length' => 1000],
+            ],
+            [
+                'type' => 'textarea',
+                'name' => 'prerequisites',
+                'label' => 'Prerequisites',
+                'required' => false,
+                'class' => 'hvac-prerequisites',
+                'placeholder' => 'Any required knowledge or certifications for attendees',
+                'validate' => ['max_length' => 1000],
+            ],
+        ];
+
+        // Add all HVAC-specific fields
+        foreach ($hvac_fields as $field) {
+            $this->add_field($field);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Add featured image upload field
+     *
+     * @param array $field_config Field configuration
+     * @return self
+     */
+    public function add_featured_image_field(array $field_config = []): self {
+        $defaults = [
+            'type' => 'file',
+            'name' => 'event_featured_image',
+            'label' => 'Featured Image',
+            'required' => false,
+            'class' => 'hvac-featured-image',
+            'description' => 'Upload a featured image for this event (JPG, PNG, WebP)',
+            'validate' => ['file_type' => ['jpg', 'jpeg', 'png', 'webp']],
+        ];
+
+        $field = wp_parse_args($field_config, $defaults);
+        return $this->add_field($field);
+    }
+
+    /**
+     * Enhanced validation for event-specific fields
+     *
+     * @param array $data Form data to validate
+     * @return array Validation errors
+     */
+    public function validate(array $data): array {
+        $errors = parent::validate($data);
+
+        // Event datetime validation
+        $errors = array_merge($errors, $this->validate_event_datetime($data));
+
+        // Venue validation
+        $errors = array_merge($errors, $this->validate_venue_data($data));
+
+        // HVAC-specific validation
+        $errors = array_merge($errors, $this->validate_hvac_fields($data));
+
+        return $errors;
+    }
+
+    /**
+     * Validate event datetime fields
+     *
+     * @param array $data Form data
+     * @return array Validation errors
+     */
+    private function validate_event_datetime(array $data): array {
+        $errors = [];
+
+        if (isset($data['event_start_date']) && isset($data['event_end_date'])) {
+            $start_time = strtotime($data['event_start_date']);
+            $end_time = strtotime($data['event_end_date']);
+
+            if ($start_time === false) {
+                $errors['event_start_date'] = 'Invalid start date format.';
+            } elseif ($start_time < time()) {
+                $errors['event_start_date'] = 'Start date cannot be in the past.';
+            }
+
+            if ($end_time === false) {
+                $errors['event_end_date'] = 'Invalid end date format.';
+            } elseif ($start_time !== false && $end_time !== false && $end_time <= $start_time) {
+                $errors['event_end_date'] = 'End date must be after start date.';
+            }
+        }
+
+        return $errors;
+    }
+
+    /**
+     * Validate venue data
+     *
+     * @param array $data Form data
+     * @return array Validation errors
+     */
+    private function validate_venue_data(array $data): array {
+        $errors = [];
+
+        // Venue capacity validation
+        if (!empty($data['venue_capacity'])) {
+            $capacity = intval($data['venue_capacity']);
+            if ($capacity < 1) {
+                $errors['venue_capacity'] = 'Venue capacity must be at least 1.';
+            } elseif ($capacity > 10000) {
+                $errors['venue_capacity'] = 'Venue capacity cannot exceed 10,000.';
+            }
+        }
+
+        return $errors;
+    }
+
+    /**
+     * Validate HVAC-specific fields
+     *
+     * @param array $data Form data
+     * @return array Validation errors
+     */
+    private function validate_hvac_fields(array $data): array {
+        $errors = [];
+
+        // Validate trainer requirements against available options
+        if (!empty($data['trainer_requirements'])) {
+            $valid_requirements = array_keys($this->get_trainer_requirement_options());
+            if (!in_array($data['trainer_requirements'], $valid_requirements)) {
+                $errors['trainer_requirements'] = 'Invalid trainer requirement selected.';
+            }
+        }
+
+        return $errors;
+    }
+
+    /**
+     * Enhanced sanitization for event fields
+     *
+     * @param array $data Raw form data
+     * @return array Sanitized data
+     */
+    public function sanitize(array $data): array {
+        $sanitized = parent::sanitize($data);
+
+        // Event-specific sanitization
+        $event_fields = [
+            'event_start_date' => 'datetime',
+            'event_end_date' => 'datetime',
+            'event_timezone' => 'text',
+            'venue_name' => 'text',
+            'venue_address' => 'textarea',
+            'venue_city' => 'text',
+            'venue_state' => 'text',
+            'venue_zip' => 'text',
+            'venue_capacity' => 'int',
+            'organizer_name' => 'text',
+            'organizer_email' => 'email',
+            'organizer_phone' => 'text',
+            'organizer_website' => 'url',
+            'trainer_requirements' => 'text',
+            'equipment_needed' => 'textarea',
+            'prerequisites' => 'textarea',
+        ];
+
+        foreach ($event_fields as $field => $sanitize_type) {
+            if (isset($data[$field])) {
+                switch ($sanitize_type) {
+                    case 'datetime':
+                        $sanitized[$field] = $this->sanitize_datetime($data[$field]);
+                        break;
+                    case 'int':
+                        $sanitized[$field] = absint($data[$field]);
+                        break;
+                    case 'email':
+                        $sanitized[$field] = sanitize_email($data[$field]);
+                        break;
+                    case 'url':
+                        $sanitized[$field] = esc_url_raw($data[$field]);
+                        break;
+                    case 'textarea':
+                        $sanitized[$field] = sanitize_textarea_field($data[$field]);
+                        break;
+                    default:
+                        $sanitized[$field] = sanitize_text_field($data[$field]);
+                }
+            }
+        }
+
+        return $sanitized;
+    }
+
+    /**
+     * Sanitize datetime input
+     *
+     * @param string $datetime Raw datetime input
+     * @return string Sanitized datetime
+     */
+    private function sanitize_datetime(string $datetime): string {
+        $timestamp = strtotime($datetime);
+        return $timestamp !== false ? date('Y-m-d\TH:i', $timestamp) : '';
+    }
+
+    /**
+     * Get WordPress timezone options
+     *
+     * @return array Timezone options
+     */
+    private function get_wordpress_timezones(): array {
+        $zones = wp_timezone_choice('UTC');
+        $timezone_options = [];
+
+        // Parse the HTML select options into key-value pairs
+        if (preg_match_all('/<option value="([^"]*)"[^>]*>([^<]*)<\/option>/', $zones, $matches)) {
+            foreach ($matches[1] as $index => $value) {
+                $timezone_options[$value] = $matches[2][$index];
+            }
+        }
+
+        return $timezone_options;
+    }
+
+    /**
+     * Get trainer requirement options
+     *
+     * @return array Trainer requirement options
+     */
+    private function get_trainer_requirement_options(): array {
+        return [
+            ''                    => 'No specific requirement',
+            'certified_trainer'   => 'Certified HVAC Trainer',
+            'master_trainer'      => 'Master Trainer',
+            'industry_expert'     => 'Industry Expert',
+            'manufacturer_rep'    => 'Manufacturer Representative',
+        ];
+    }
+
+    /**
+     * Get certification level options
+     *
+     * @return array Certification level options
+     */
+    private function get_certification_level_options(): array {
+        return [
+            'basic'        => 'Basic HVAC',
+            'intermediate' => 'Intermediate HVAC',
+            'advanced'     => 'Advanced HVAC',
+            'commercial'   => 'Commercial Systems',
+            'residential'  => 'Residential Systems',
+            'refrigeration' => 'Refrigeration',
+        ];
+    }
+
+    /**
+     * Create complete event creation form
+     *
+     * @return self Configured form builder
+     */
+    public function create_event_form(): self {
+        // Basic event information
+        $this->add_field([
+            'type' => 'text',
+            'name' => 'event_title',
+            'label' => 'Event Title',
+            'required' => true,
+            'class' => 'hvac-event-title',
+            'placeholder' => 'Enter event title',
+        ]);
+
+        $this->add_field([
+            'type' => 'textarea',
+            'name' => 'event_description',
+            'label' => 'Event Description',
+            'required' => true,
+            'class' => 'hvac-event-description',
+            'placeholder' => 'Describe the event in detail',
+            'validate' => ['min_length' => 50],
+        ]);
+
+        $this->add_field([
+            'type' => 'textarea',
+            'name' => 'event_excerpt',
+            'label' => 'Event Summary',
+            'required' => false,
+            'class' => 'hvac-event-excerpt',
+            'placeholder' => 'Brief summary for event listings',
+            'validate' => ['max_length' => 300],
+        ]);
+
+        // DateTime fields
+        $this->add_datetime_field([
+            'name' => 'event_start_date',
+            'label' => 'Start Date & Time',
+            'required' => true,
+        ]);
+
+        $this->add_datetime_field([
+            'name' => 'event_end_date',
+            'label' => 'End Date & Time',
+            'required' => true,
+        ]);
+
+        $this->add_all_day_field();
+        $this->add_timezone_field();
+
+        // Event URL
+        $this->add_field([
+            'type' => 'url',
+            'name' => 'event_url',
+            'label' => 'Event Website',
+            'required' => false,
+            'class' => 'hvac-event-url',
+            'placeholder' => 'https://example.com/event-info',
+            'validate' => ['url'],
+        ]);
+
+        // Venue and organizer information
+        $this->add_venue_group();
+        $this->add_organizer_group();
+
+        // HVAC-specific fields
+        $this->add_hvac_fields();
+
+        // Featured image
+        $this->add_featured_image_field();
+
+        return $this;
+    }
+
+    /**
+     * Create event editing form with pre-populated data
+     *
+     * @param int $event_id Event post ID
+     * @return self Configured form builder
+     */
+    public function create_edit_form(int $event_id): self {
+        // Create the form structure
+        $this->create_event_form();
+
+        // Pre-populate with event data
+        $event_data = $this->get_event_data($event_id);
+        if (!empty($event_data)) {
+            $this->set_data($event_data);
+        }
+
+        // Add event ID as hidden field
+        $this->add_field([
+            'type' => 'hidden',
+            'name' => 'event_id',
+            'value' => (string)$event_id,
+        ]);
+
+        return $this;
+    }
+
+    /**
+     * Get event data for form pre-population
+     *
+     * @param int $event_id Event post ID
+     * @return array Event data
+     */
+    private function get_event_data(int $event_id): array {
+        $post = get_post($event_id);
+        if (!$post || $post->post_type !== 'tribe_events') {
+            return [];
+        }
+
+        return [
+            'event_title' => $post->post_title,
+            'event_description' => $post->post_content,
+            'event_excerpt' => $post->post_excerpt,
+            'event_start_date' => get_post_meta($event_id, '_EventStartDate', true),
+            'event_end_date' => get_post_meta($event_id, '_EventEndDate', true),
+            'event_timezone' => get_post_meta($event_id, '_EventTimezone', true),
+            'event_url' => get_post_meta($event_id, '_EventURL', true),
+            // Add more meta field mappings as needed
+        ];
+    }
+}

includes/class-hvac-event-manager.php

@@ -1038,21 +1038,5 @@ final class HVAC_Event_Manager {
     }
 }
 
-/**
+// HVAC_Singleton_Trait moved to standalone file: trait-hvac-singleton.php
- * Singleton trait for memory efficiency
+// This provides better code organization and prevents conflicts
- */
-trait HVAC_Singleton_Trait {
-    private static ?self $instance = null;
-    
-    public static function instance(): self {
-        if (self::$instance === null) {
-            self::$instance = new self();
-        }
-        return self::$instance;
-    }
-    
-    private function __clone() {}
-    public function __wakeup() {
-        throw new Exception("Cannot unserialize singleton");
-    }
-}

includes/class-hvac-plugin.php

@@ -193,6 +193,18 @@ final class HVAC_Plugin {
         // TEC Integration - Load early for proper routing
         require_once HVAC_PLUGIN_DIR . 'includes/class-hvac-tec-integration.php';
         
+        // Load singleton trait first (required by multiple classes)
+        require_once HVAC_PLUGIN_DIR . 'includes/trait-hvac-singleton.php';
+
+        // Core security framework
+        require_once HVAC_PLUGIN_DIR . 'includes/class-hvac-security.php';
+
+        // Form building framework
+        require_once HVAC_PLUGIN_DIR . 'includes/class-hvac-form-builder.php';
+
+        // Native event form builder (Phase 1A - Native WordPress Events)
+        require_once HVAC_PLUGIN_DIR . 'includes/class-hvac-event-form-builder.php';
+
         // Unified Event Management System (replaces 8+ fragmented implementations)
         require_once HVAC_PLUGIN_DIR . 'includes/class-hvac-event-manager.php';
         

includes/trait-hvac-singleton.php

@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * HVAC Singleton Trait
+ *
+ * Provides singleton pattern implementation for HVAC classes
+ * Ensures memory efficiency and single instance management
+ *
+ * @package    HVAC_Community_Events
+ * @subpackage Includes
+ * @since      3.0.0
+ */
+
+if (!defined('ABSPATH')) {
+    exit;
+}
+
+/**
+ * Trait HVAC_Singleton_Trait
+ *
+ * Memory-efficient singleton implementation for HVAC classes
+ */
+trait HVAC_Singleton_Trait {
+
+    /**
+     * Single instance of the class
+     *
+     * @var static|null
+     */
+    private static ?self $instance = null;
+
+    /**
+     * Get singleton instance
+     *
+     * @return static
+     */
+    public static function instance(): self {
+        if (self::$instance === null) {
+            self::$instance = new self();
+        }
+        return self::$instance;
+    }
+
+    /**
+     * Prevent cloning
+     */
+    private function __clone() {}
+
+    /**
+     * Prevent unserialization
+     *
+     * @throws Exception
+     */
+    public function __wakeup() {
+        throw new Exception("Cannot unserialize singleton");
+    }
+}

templates/page-native-event-test.php

@@ -0,0 +1,232 @@
+<?php
+/**
+ * Template Name: Native Event Test
+ * Description: Test template for native WordPress event form functionality
+ */
+
+// Define constant to indicate we are in a page template
+define('HVAC_IN_PAGE_TEMPLATE', true);
+
+get_header();
+?>
+
+<style>
+.hvac-native-event-test {
+    max-width: 1200px;
+    margin: 0 auto;
+    padding: 20px;
+}
+
+.hvac-native-event-test h1 {
+    color: #1a1a1a;
+    font-size: 28px;
+    margin-bottom: 20px;
+}
+
+.hvac-form-notice {
+    background: #f0f7ff;
+    border: 1px solid #0073aa;
+    border-radius: 4px;
+    padding: 12px;
+    margin-bottom: 20px;
+}
+
+.hvac-form-notice p {
+    margin: 0;
+    color: #0073aa;
+}
+
+.form-group {
+    margin-bottom: 20px;
+}
+
+.form-group label {
+    display: block;
+    font-weight: bold;
+    margin-bottom: 5px;
+}
+
+.form-group input,
+.form-group textarea,
+.form-group select {
+    width: 100%;
+    padding: 8px;
+    border: 1px solid #ddd;
+    border-radius: 4px;
+    box-sizing: border-box;
+}
+
+.form-group textarea {
+    height: 100px;
+    resize: vertical;
+}
+
+.venue-group,
+.organizer-group {
+    border: 1px solid #e0e0e0;
+    padding: 15px;
+    border-radius: 5px;
+    margin: 20px 0;
+}
+
+.venue-group h3,
+.organizer-group h3 {
+    margin-top: 0;
+    color: #0073aa;
+}
+
+.required {
+    color: #d00;
+}
+
+.error {
+    color: #d00;
+    font-size: 14px;
+    display: block;
+    margin-top: 5px;
+}
+
+.button {
+    background: #0073aa;
+    color: white;
+    padding: 10px 20px;
+    border: none;
+    border-radius: 4px;
+    cursor: pointer;
+}
+
+.button:hover {
+    background: #005177;
+}
+
+.success-message {
+    background: #d4edda;
+    border: 1px solid #c3e6cb;
+    color: #155724;
+    padding: 12px;
+    border-radius: 4px;
+    margin-bottom: 20px;
+}
+</style>
+
+<div class="hvac-native-event-test">
+    <?php
+    // Display trainer navigation menu
+    if (class_exists('HVAC_Menu_System')) {
+        HVAC_Menu_System::instance()->render_trainer_menu();
+    }
+    ?>
+
+    <h1>Native Event Form Builder Test</h1>
+
+    <div class="hvac-form-notice">
+        <p><strong>Phase 1A Testing:</strong> This page tests the new HVAC_Event_Form_Builder with datetime, venue, organizer, and HVAC-specific fields.</p>
+    </div>
+
+    <?php
+    $form_submitted = false;
+    $form_errors = [];
+    $success_message = '';
+
+    // Handle form submission
+    if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['hvac_event_form_nonce'])) {
+
+        // Verify nonce for security
+        if (wp_verify_nonce($_POST['hvac_event_form_nonce'], 'hvac_event_form')) {
+
+            try {
+                // Create event form builder instance
+                $event_form = new HVAC_Event_Form_Builder('hvac_event_form');
+                $event_form->create_event_form();
+
+                // Validate submitted data
+                $form_errors = $event_form->validate($_POST);
+
+                if (empty($form_errors)) {
+                    // Sanitize data
+                    $sanitized_data = $event_form->sanitize($_POST);
+
+                    // Process the form (this would normally create the event)
+                    $success_message = 'Event form validation successful! Data has been sanitized and is ready for processing.';
+                    $form_submitted = true;
+
+                    // In Phase 1B, this is where we would create the tribe_events post
+
+                } else {
+                    $event_form->set_errors($form_errors);
+                }
+
+            } catch (Exception $e) {
+                $form_errors['general'] = 'Form processing error: ' . $e->getMessage();
+            }
+
+        } else {
+            $form_errors['nonce'] = 'Security check failed. Please refresh the page and try again.';
+        }
+    }
+
+    // Display success message
+    if ($success_message) {
+        echo '<div class="success-message">' . esc_html($success_message) . '</div>';
+    }
+
+    // Display general errors
+    if (isset($form_errors['general'])) {
+        echo '<div class="error" style="background: #f8d7da; border: 1px solid #f5c6cb; padding: 12px; border-radius: 4px; margin-bottom: 20px;">';
+        echo esc_html($form_errors['general']);
+        echo '</div>';
+    }
+
+    if (isset($form_errors['nonce'])) {
+        echo '<div class="error" style="background: #f8d7da; border: 1px solid #f5c6cb; padding: 12px; border-radius: 4px; margin-bottom: 20px;">';
+        echo esc_html($form_errors['nonce']);
+        echo '</div>';
+    }
+
+    // Create and display the event form
+    try {
+        $event_form = new HVAC_Event_Form_Builder('hvac_event_form');
+        $event_form->create_event_form();
+
+        // Set any existing errors
+        if (!empty($form_errors)) {
+            $event_form->set_errors($form_errors);
+        }
+
+        // Set form data if submitted (for re-population on errors)
+        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
+            $event_form->set_data($_POST);
+        }
+
+        // Add some custom wrapper HTML
+        echo '<div class="native-event-form-wrapper">';
+        echo '<h3>Event Information</h3>';
+        echo $event_form->render();
+        echo '</div>';
+
+    } catch (Exception $e) {
+        echo '<div class="error" style="background: #f8d7da; border: 1px solid #f5c6cb; padding: 12px; border-radius: 4px;">';
+        echo 'Form Builder Error: ' . esc_html($e->getMessage());
+        echo '</div>';
+    }
+    ?>
+
+    <div style="margin-top: 30px; padding: 15px; background: #f9f9f9; border-radius: 4px;">
+        <h4>Phase 1A Implementation Status:</h4>
+        <ul>
+            <li>✅ HVAC_Event_Form_Builder class created</li>
+            <li>✅ DateTime field types (start/end dates, timezone, all-day)</li>
+            <li>✅ Venue field group (name, address, capacity, coordinates)</li>
+            <li>✅ Organizer field group (name, email, phone, website)</li>
+            <li>✅ HVAC-specific fields (trainer requirements, certifications, equipment)</li>
+            <li>✅ Featured image upload support</li>
+            <li>✅ WordPress security integration (nonce, sanitization, validation)</li>
+            <li>✅ Form validation and error handling</li>
+            <li>⏳ Next: Phase 1B - tribe_events post creation integration</li>
+        </ul>
+    </div>
+</div>
+
+<?php
+get_footer();
+?>