<?php
/**
 * Block Checkout Simple Frontend
 * Handles field visibility, custom fields, and ordering
 */

if (!defined('ABSPATH')) exit;

class CFEP_Block_Simple_Frontend {
    
    private static $instance = null;
    
    public static function instance() {
        if (is_null(self::$instance)) {
            self::$instance = new self();
        }
        return self::$instance;
    }
    
    private function __construct() {
        // CRITICAL: Only hook if Block Checkout is actually being used
        // This prevents Block field settings from affecting Classic Checkout
        add_action('wp', array($this, 'maybe_init_hooks'), 5);
    }
    
    /**
     * Initialize hooks only if Block Checkout is active on this page
     */
    public function maybe_init_hooks() {
        // Only run on checkout page
        if (!is_checkout() || is_order_received_page()) {
            return;
        }
        
        // Check if Block Checkout is being used
        if (!$this->is_block_checkout_active()) {
            return;
        }
        
        
        // Modify all checkout fields
        add_filter('woocommerce_checkout_fields', array($this, 'modify_all_fields'), 9999);
        
        // Specific field type filters
        add_filter('woocommerce_billing_fields', array($this, 'modify_billing_fields'), 9999);
        add_filter('woocommerce_shipping_fields', array($this, 'modify_shipping_fields'), 9999);
        
        // Add custom fields to checkout
        add_action('woocommerce_checkout_fields', array($this, 'add_custom_fields'), 9999);
        
        // Save custom fields
        add_action('woocommerce_checkout_create_order', array($this, 'save_fields_to_order'), 10, 2);
        add_action('woocommerce_store_api_checkout_update_order_from_request', array($this, 'save_block_fields'), 10, 2);
        
        // Display in admin
        add_action('woocommerce_admin_order_data_after_billing_address', array($this, 'display_in_admin'), 10, 1);
    }
    
    /**
     * Detect if Block Checkout is active on current page
     */
    private function is_block_checkout_active() {
        // Method 1: Check Store API (Block Checkout ALWAYS uses Store API)
        if (did_action('woocommerce_store_api_checkout_update_order_from_request')) {
            return true;
        }
        
        // Method 2: Check if checkout page uses blocks
        $checkout_page_id = wc_get_page_id('checkout');
        if ($checkout_page_id) {
            $post = get_post($checkout_page_id);
            
            // If has shortcode, it's DEFINITELY Classic
            if ($post && has_shortcode($post->post_content, 'woocommerce_checkout')) {
                return false;
            }
            
            // If has blocks, check for checkout block
            if ($post && has_blocks($post->post_content)) {
                if (has_block('woocommerce/checkout', $post)) {
                    return true;
                }
            }
        }
        
        // Method 3: Check for Block Checkout specific classes in the DOM
        // (This won't work in PHP, but we default to Classic to be safe)
        return false;
    }
    
    /**
     * Modify all checkout fields - visibility, labels, order
     */
    public function modify_all_fields($fields) {
        
        if (!class_exists('CFEP_Block_Field_Manager')) {
            return $fields;
        }
        
        $block_manager = CFEP_Block_Field_Manager::instance();
        $all_block_fields = $block_manager->get_all_fields(null, false);
        
        
        foreach ($all_block_fields as $block_field) {
            $field_key = $block_field['field_key'];
            $enabled = (int) $block_field['enabled'];
            $is_default = (int) $block_field['is_default'];
            $position = (int) $block_field['position'];
            
            // Determine section
            $section = $this->get_field_section($field_key, $block_field['location']);
            
            
            // If disabled, remove it
            if ($enabled === 0) {
                if (isset($fields[$section][$field_key])) {
                    unset($fields[$section][$field_key]);
                }
                continue;
            }
            
            // If it's a default field, modify it
            if ($is_default === 1 && isset($fields[$section][$field_key])) {
                $fields[$section][$field_key]['label'] = $block_field['label'];
                $fields[$section][$field_key]['required'] = (bool) $block_field['required'];
                $fields[$section][$field_key]['priority'] = $position;
                
                if (!empty($block_field['placeholder'])) {
                    $fields[$section][$field_key]['placeholder'] = $block_field['placeholder'];
                }
                
            }
            
            // If it's custom, add it
            if ($is_default !== 1) {
                if (!isset($fields[$section])) {
                    $fields[$section] = array();
                }
                
                $fields[$section][$field_key] = array(
                    'type' => $block_field['field_type'],
                    'label' => $block_field['label'],
                    'required' => (bool) $block_field['required'],
                    'class' => array('form-row-wide'),
                    'priority' => $position,
                    'placeholder' => $block_field['placeholder'] ?? ''
                );
                
                // Add options for select
                if ($block_field['field_type'] === 'select' && !empty($block_field['options'])) {
                    $options = maybe_unserialize($block_field['options']);
                    if (is_array($options)) {
                        $fields[$section][$field_key]['options'] = $options;
                    }
                }
                
            }
        }
        
        return $fields;
    }
    
    /**
     * Modify billing fields specifically
     */
    public function modify_billing_fields($fields) {
        if (!class_exists('CFEP_Block_Field_Manager')) {
            return $fields;
        }
        
        $block_manager = CFEP_Block_Field_Manager::instance();
        $all_block_fields = $block_manager->get_all_fields(null, false);
        
        foreach ($all_block_fields as $block_field) {
            if (strpos($block_field['field_key'], 'billing_') !== 0) {
                continue;
            }
            
            $field_key = $block_field['field_key'];
            $enabled = (int) $block_field['enabled'];
            $position = (int) $block_field['position'];
            
            // Remove if disabled
            if ($enabled === 0 && isset($fields[$field_key])) {
                unset($fields[$field_key]);
                continue;
            }
            
            // Update if exists
            if (isset($fields[$field_key])) {
                $fields[$field_key]['label'] = $block_field['label'];
                $fields[$field_key]['required'] = (bool) $block_field['required'];
                $fields[$field_key]['priority'] = $position;
                
                if (!empty($block_field['placeholder'])) {
                    $fields[$field_key]['placeholder'] = $block_field['placeholder'];
                }
            }
        }
        
        return $fields;
    }
    
    /**
     * Modify shipping fields specifically
     */
    public function modify_shipping_fields($fields) {
        if (!class_exists('CFEP_Block_Field_Manager')) {
            return $fields;
        }
        
        $block_manager = CFEP_Block_Field_Manager::instance();
        $all_block_fields = $block_manager->get_all_fields(null, false);
        
        foreach ($all_block_fields as $block_field) {
            if (strpos($block_field['field_key'], 'shipping_') !== 0) {
                continue;
            }
            
            $field_key = $block_field['field_key'];
            $enabled = (int) $block_field['enabled'];
            $position = (int) $block_field['position'];
            
            // Remove if disabled
            if ($enabled === 0 && isset($fields[$field_key])) {
                unset($fields[$field_key]);
                continue;
            }
            
            // Update if exists
            if (isset($fields[$field_key])) {
                $fields[$field_key]['label'] = $block_field['label'];
                $fields[$field_key]['required'] = (bool) $block_field['required'];
                $fields[$field_key]['priority'] = $position;
                
                if (!empty($block_field['placeholder'])) {
                    $fields[$field_key]['placeholder'] = $block_field['placeholder'];
                }
            }
        }
        
        return $fields;
    }
    
    /**
     * Add custom fields to checkout
     */
    public function add_custom_fields($fields) {
        // Already handled in modify_all_fields
        return $fields;
    }
    
    /**
     * Get field section from key and location
     */
    private function get_field_section($field_key, $location) {
        // Check key prefix first
        if (strpos($field_key, 'billing_') === 0) {
            return 'billing';
        }
        if (strpos($field_key, 'shipping_') === 0) {
            return 'shipping';
        }
        if ($field_key === 'order_comments') {
            return 'order';
        }
        
        // Map location to section
        $mapping = array(
            'contact' => 'billing',
            'address' => 'shipping',
            'billing' => 'billing',
            'additional' => 'order'
        );
        
        return $mapping[$location] ?? 'billing';
    }
    
    /**
     * Save custom fields to order
     */
    public function save_fields_to_order($order, $data) {
        if (!class_exists('CFEP_Block_Field_Manager')) {
            return;
        }
        
        $block_manager = CFEP_Block_Field_Manager::instance();
        $custom_fields = $block_manager->get_all_fields(null, true);
        
        foreach ($custom_fields as $field) {
            if ((int) $field['is_default'] === 1) {
                continue;
            }
            
            $field_key = $field['field_key'];
            
            // phpcs:ignore WordPress.Security.NonceVerification.Missing, WordPress.Security.ValidatedSanitizedInput.MissingUnslash
            if (isset($_POST[$field_key])) {
                // phpcs:ignore WordPress.Security.NonceVerification.Missing, WordPress.Security.ValidatedSanitizedInput.MissingUnslash
                $value = sanitize_text_field(wp_unslash($_POST[$field_key]));
                $order->update_meta_data('_' . $field_key, $value);
            }
        }
    }
    
    /**
     * Save Block Checkout fields
     */
    public function save_block_fields($order, $request) {
        if (!class_exists('CFEP_Block_Field_Manager')) {
            return;
        }
        
        $block_manager = CFEP_Block_Field_Manager::instance();
        $custom_fields = $block_manager->get_all_fields(null, true);
        
        $request_data = $request->get_params();
        
        foreach ($custom_fields as $field) {
            if ((int) $field['is_default'] === 1) {
                continue;
            }
            
            $field_key = $field['field_key'];
            $value = null;
            
            if (isset($request_data[$field_key])) {
                $value = $request_data[$field_key];
            } elseif (isset($request_data['extensions']['cfep-block-fields'][$field_key])) {
                $value = $request_data['extensions']['cfep-block-fields'][$field_key];
            }
            
            if ($value !== null) {
                $order->update_meta_data('_' . $field_key, sanitize_text_field($value));
            }
        }
        
        $order->save();
    }
    
    /**
     * Display custom fields in admin
     */
    public function display_in_admin($order) {
        if (!class_exists('CFEP_Block_Field_Manager')) {
            return;
        }
        
        $block_manager = CFEP_Block_Field_Manager::instance();
        $custom_fields = $block_manager->get_all_fields(null, true);
        
        $has_data = false;
        $output = '<div style="margin-top:20px;"><h3>Custom Fields</h3>';
        
        foreach ($custom_fields as $field) {
            if ((int) $field['is_default'] === 1) {
                continue;
            }
            
            $value = $order->get_meta('_' . $field['field_key']);
            
            if (!empty($value)) {
                $has_data = true;
                $output .= '<p><strong>' . esc_html($field['label']) . ':</strong> ' . esc_html($value) . '</p>';
            }
        }
        
        $output .= '</div>';
        
        if ($has_data) {
            // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- HTML built with escaped values
            echo $output;
        }
    }
}