<?php
/**
 * HSSM Slides Custom Post Type
 * 
 * Manages the custom post type for slides with detailed fields for multi-site management
 * 
 * @package Hi_School_Slide_Manager
 * @since 1.0.0
 */

// Prevent direct access
if ( ! defined( 'ABSPATH' ) ) {
    exit( 'Direct access forbidden.' );
}

/**
 * HSSM Slides CPT Class
 * 
 * Handles the slides custom post type and its meta fields
 */
class HSSM_Slides_CPT {
    
    /**
     * Post type slug
     * 
     * @since 1.0.0
     * @var string
     */
    const POST_TYPE = 'hssm_slide';
    
    /**
     * Site taxonomy slug
     * 
     * @since 1.0.0
     * @var string
     */
    const SITE_TAXONOMY = 'hssm_site';
    
    /**
     * Client taxonomy slug
     * 
     * @since 1.0.0
     * @var string
     */
    const CLIENT_TAXONOMY = 'hssm_client';
    
    /**
     * Constructor
     * 
     * @since 1.0.0
     */
    public function __construct() {
        add_action( 'add_meta_boxes', array( $this, 'add_meta_boxes' ) );
        add_action( 'save_post', array( $this, 'save_meta_fields' ) );
        add_filter( 'manage_' . self::POST_TYPE . '_posts_columns', array( $this, 'add_custom_columns' ) );
        add_action( 'manage_' . self::POST_TYPE . '_posts_custom_column', array( $this, 'custom_column_content' ), 10, 2 );
        
        // Add drag-and-drop ordering functionality
        add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_admin_scripts' ) );
        add_action( 'wp_ajax_hssm_update_slide_order', array( $this, 'ajax_update_slide_order' ) );
    }
    
    /**
     * Register the slides custom post type
     * 
     * @since 1.0.0
     */
    public function register() {
        $labels = array(
            'name'                  => _x( 'Slides', 'Post type general name', 'hi-school-slide-manager' ),
            'singular_name'         => _x( 'Slide', 'Post type singular name', 'hi-school-slide-manager' ),
            'menu_name'             => _x( 'Slides', 'Admin Menu text', 'hi-school-slide-manager' ),
            'name_admin_bar'        => _x( 'Slide', 'Add New on Toolbar', 'hi-school-slide-manager' ),
            'add_new'               => __( 'Add New', 'hi-school-slide-manager' ),
            'add_new_item'          => __( 'Add New Slide', 'hi-school-slide-manager' ),
            'new_item'              => __( 'New Slide', 'hi-school-slide-manager' ),
            'edit_item'             => __( 'Edit Slide', 'hi-school-slide-manager' ),
            'view_item'             => __( 'View Slide', 'hi-school-slide-manager' ),
            'all_items'             => __( 'All Slides', 'hi-school-slide-manager' ),
            'search_items'          => __( 'Search Slides', 'hi-school-slide-manager' ),
            'parent_item_colon'     => __( 'Parent Slides:', 'hi-school-slide-manager' ),
            'not_found'             => __( 'No slides found.', 'hi-school-slide-manager' ),
            'not_found_in_trash'    => __( 'No slides found in Trash.', 'hi-school-slide-manager' ),
            'featured_image'        => _x( 'Background Image', 'Overrides the "Featured Image" phrase', 'hi-school-slide-manager' ),
            'set_featured_image'    => _x( 'Set background image', 'Overrides the "Set featured image" phrase', 'hi-school-slide-manager' ),
            'remove_featured_image' => _x( 'Remove background image', 'Overrides the "Remove featured image" phrase', 'hi-school-slide-manager' ),
            'use_featured_image'    => _x( 'Use as background image', 'Overrides the "Use as featured image" phrase', 'hi-school-slide-manager' ),
            'archives'              => _x( 'Slide archives', 'The post type archive label used in nav menus', 'hi-school-slide-manager' ),
            'insert_into_item'      => _x( 'Insert into slide', 'Overrides the "Insert into post" phrase', 'hi-school-slide-manager' ),
            'uploaded_to_this_item' => _x( 'Uploaded to this slide', 'Overrides the "Uploaded to this post" phrase', 'hi-school-slide-manager' ),
            'filter_items_list'     => _x( 'Filter slides list', 'Screen reader text for the filter links', 'hi-school-slide-manager' ),
            'items_list_navigation' => _x( 'Slides list navigation', 'Screen reader text for the pagination', 'hi-school-slide-manager' ),
            'items_list'            => _x( 'Slides list', 'Screen reader text for the items list', 'hi-school-slide-manager' ),
        );
        
        $args = array(
            'labels'             => $labels,
            'public'             => true,
            'publicly_queryable' => true,
            'show_ui'            => true,
            'show_in_menu'       => true,
            'query_var'          => true,
            'rewrite'            => array( 'slug' => 'slide' ),
            'capability_type'    => 'post',
            'has_archive'        => true,
            'hierarchical'       => false,
            'menu_position'      => 20,
            'menu_icon'          => 'dashicons-slides',
            'supports'           => array( 'title', 'editor', 'thumbnail', 'excerpt' ),
            'show_in_rest'       => true,
            'rest_base'          => 'slides',
        );
        
        register_post_type( self::POST_TYPE, $args );
    }
    
    /**
     * Register custom taxonomies
     * 
     * @since 1.0.0
     */
    public function register_taxonomies() {
        // Site taxonomy for organizing slides by target site
        $site_labels = array(
            'name'              => _x( 'Target Sites', 'taxonomy general name', 'hi-school-slide-manager' ),
            'singular_name'     => _x( 'Target Site', 'taxonomy singular name', 'hi-school-slide-manager' ),
            'search_items'      => __( 'Search Sites', 'hi-school-slide-manager' ),
            'all_items'         => __( 'All Sites', 'hi-school-slide-manager' ),
            'parent_item'       => __( 'Parent Site', 'hi-school-slide-manager' ),
            'parent_item_colon' => __( 'Parent Site:', 'hi-school-slide-manager' ),
            'edit_item'         => __( 'Edit Site', 'hi-school-slide-manager' ),
            'update_item'       => __( 'Update Site', 'hi-school-slide-manager' ),
            'add_new_item'      => __( 'Add New Site', 'hi-school-slide-manager' ),
            'new_item_name'     => __( 'New Site Name', 'hi-school-slide-manager' ),
            'menu_name'         => __( 'Target Sites', 'hi-school-slide-manager' ),
        );
        
        $site_args = array(
            'hierarchical'      => false,
            'labels'            => $site_labels,
            'show_ui'           => true,
            'show_admin_column' => true,
            'query_var'         => true,
            'rewrite'           => array( 'slug' => 'slide-site' ),
            'show_in_rest'      => true,
        );
        
        register_taxonomy( self::SITE_TAXONOMY, array( self::POST_TYPE ), $site_args );
        
        // Client taxonomy for organizing slides by client (optional)
        $client_labels = array(
            'name'              => _x( 'Clients', 'taxonomy general name', 'hi-school-slide-manager' ),
            'singular_name'     => _x( 'Client', 'taxonomy singular name', 'hi-school-slide-manager' ),
            'search_items'      => __( 'Search Clients', 'hi-school-slide-manager' ),
            'all_items'         => __( 'All Clients', 'hi-school-slide-manager' ),
            'parent_item'       => __( 'Parent Client', 'hi-school-slide-manager' ),
            'parent_item_colon' => __( 'Parent Client:', 'hi-school-slide-manager' ),
            'edit_item'         => __( 'Edit Client', 'hi-school-slide-manager' ),
            'update_item'       => __( 'Update Client', 'hi-school-slide-manager' ),
            'add_new_item'      => __( 'Add New Client', 'hi-school-slide-manager' ),
            'new_item_name'     => __( 'New Client Name', 'hi-school-slide-manager' ),
            'menu_name'         => __( 'Clients', 'hi-school-slide-manager' ),
        );
        
        $client_args = array(
            'hierarchical'      => false,
            'labels'            => $client_labels,
            'show_ui'           => true,
            'show_admin_column' => true,
            'query_var'         => true,
            'rewrite'           => array( 'slug' => 'slide-client' ),
            'show_in_rest'      => true,
        );
        
        register_taxonomy( self::CLIENT_TAXONOMY, array( self::POST_TYPE ), $client_args );
        
        // Add default terms for the three companion sites
        $this->create_default_site_terms();
    }
    
    /**
     * Create default site terms for the three companion sites
     *
     * @since 1.0.0
     */
    private function create_default_site_terms() {
        $default_sites = array();
        
        // Use centralized method from HSSM_Main if available
        if ( class_exists( 'HSSM_Main' ) && method_exists( 'HSSM_Main', 'get_companion_sites' ) ) {
            $default_sites = HSSM_Main::get_companion_sites();
        } else {
            // Fallback
            $default_sites = array(
                array(
                    'slug' => 'hi-school',
                    'name' => 'Hi-School Pharmacy',
                    'description' => 'Hi-School Pharmacy companion site'
                ),
                array(
                    'slug' => 'one-stop',
                    'name' => 'One Stop Hardware',
                    'description' => 'One Stop Hardware companion site'
                ),
                array(
                    'slug' => 'ace',
                    'name' => 'Ace Hardware',
                    'description' => 'Ace Hardware companion site'
                )
            );
        }
        
        foreach ( $default_sites as $site ) {
            if ( ! term_exists( $site['slug'], self::SITE_TAXONOMY ) ) {
                wp_insert_term(
                    $site['name'],
                    self::SITE_TAXONOMY,
                    array(
                        'slug' => $site['slug'],
                        'description' => $site['description']
                    )
                );
            }
        }
    }
    
    /**
     * Add meta boxes for slide fields
     * 
     * @since 1.0.0
     */
    public function add_meta_boxes() {
        add_meta_box(
            'hssm_slide_details',
            __( 'Slide Details', 'hi-school-slide-manager' ),
            array( $this, 'slide_details_meta_box' ),
            self::POST_TYPE,
            'normal',
            'high'
        );
        
        add_meta_box(
            'hssm_background_image_help',
            __( 'Background Image Guidelines', 'hi-school-slide-manager' ),
            array( $this, 'background_image_help_meta_box' ),
            self::POST_TYPE,
            'side',
            'high'
        );
        
        add_meta_box(
            'hssm_slide_scheduling',
            __( 'Slide Scheduling', 'hi-school-slide-manager' ),
            array( $this, 'slide_scheduling_meta_box' ),
            self::POST_TYPE,
            'side',
            'default'
        );
        
        add_meta_box(
            'hssm_slide_targeting',
            __( 'Site Targeting', 'hi-school-slide-manager' ),
            array( $this, 'slide_targeting_meta_box' ),
            self::POST_TYPE,
            'side',
            'default'
        );
    }
    
    /**
     * Render slide details meta box
     * 
     * @since 1.0.0
     * @param WP_Post $post Current post object
     */
    public function slide_details_meta_box( $post ) {
        wp_nonce_field( 'hssm_save_slide_meta', 'hssm_slide_meta_nonce' );
        
        $subtitle = get_post_meta( $post->ID, '_hssm_subtitle', true );
        $buttons = get_post_meta( $post->ID, '_hssm_buttons', true );
        $order = get_post_meta( $post->ID, '_hssm_order', true );
        $hide_all_text = get_post_meta( $post->ID, '_hssm_hide_all_text', true );
        
        // Initialize buttons array if empty
        if ( ! is_array( $buttons ) || empty( $buttons ) ) {
            $buttons = array(
                array( 'text' => 'Learn More', 'url' => '' )
            );
        }
        
        ?>
        <table class="form-table">
            <tr>
                <th scope="row">
                    <label for="hssm_subtitle"><?php _e( 'Subtitle', 'hi-school-slide-manager' ); ?></label>
                </th>
                <td>
                    <input type="text" id="hssm_subtitle" name="hssm_subtitle" value="<?php echo esc_attr( $subtitle ); ?>" class="regular-text" />
                    <p class="description"><?php _e( 'Optional subtitle for the slide', 'hi-school-slide-manager' ); ?></p>
                </td>
            </tr>
            <tr>
                <th scope="row">
                    <label><?php _e( 'Call-to-Action Buttons', 'hi-school-slide-manager' ); ?></label>
                </th>
                <td>
                    <div id="hssm-buttons-container">
                        <?php foreach ( $buttons as $index => $button ) : ?>
                            <div class="hssm-button-row" data-index="<?php echo esc_attr( $index ); ?>">
                                <div class="hssm-button-fields">
                                    <label><?php _e( 'Button Text:', 'hi-school-slide-manager' ); ?></label>
                                    <input type="text" name="hssm_buttons[<?php echo esc_attr( $index ); ?>][text]" value="<?php echo esc_attr( $button['text'] ?: 'Learn More' ); ?>" class="regular-text" placeholder="Learn More" />
                                    
                                    <label><?php _e( 'Button URL:', 'hi-school-slide-manager' ); ?></label>
                                    <input type="url" name="hssm_buttons[<?php echo esc_attr( $index ); ?>][url]" value="<?php echo esc_url( $button['url'] ?: '' ); ?>" class="regular-text" placeholder="https://example.com" />
                                    
                                    <button type="button" class="button hssm-remove-button" <?php echo count( $buttons ) <= 1 ? 'style="display:none;"' : ''; ?>><?php _e( 'Remove', 'hi-school-slide-manager' ); ?></button>
                                </div>
                            </div>
                        <?php endforeach; ?>
                    </div>
                    
                    <p>
                        <button type="button" id="hssm-add-button" class="button button-secondary"><?php _e( 'Add Another Button', 'hi-school-slide-manager' ); ?></button>
                        <span class="description"><?php _e( '(Maximum 5 buttons)', 'hi-school-slide-manager' ); ?></span>
                    </p>
                    
                    <p class="description"><?php _e( 'Add call-to-action buttons for the slide. The first button is typically the primary action.', 'hi-school-slide-manager' ); ?></p>
                </td>
            </tr>
            <tr>
                <th scope="row">
                    <label for="hssm_order"><?php _e( 'Display Order', 'hi-school-slide-manager' ); ?></label>
                </th>
                <td>
                    <input type="number" id="hssm_order" name="hssm_order" value="<?php echo esc_attr( $order ?: 0 ); ?>" min="0" />
                    <p class="description"><?php _e( 'Display order for the slide (lower numbers show first). You can also drag and drop to reorder slides in the list view.', 'hi-school-slide-manager' ); ?></p>
                </td>
            </tr>
            <tr>
                <th scope="row">
                    <label for="hssm_hide_all_text"><?php _e( 'Text Visibility', 'hi-school-slide-manager' ); ?></label>
                </th>
                <td>
                    <label>
                        <input type="checkbox" id="hssm_hide_all_text" name="hssm_hide_all_text" value="1" <?php checked( $hide_all_text, '1' ); ?> />
                        <?php _e( 'Hide All Text (Image Only)', 'hi-school-slide-manager' ); ?>
                    </label>
                    <p class="description"><?php _e( 'If checked, the title, subtitle, and buttons will not be displayed on the slide.', 'hi-school-slide-manager' ); ?></p>
                </td>
            </tr>
        </table>
        
        <style>
            .hssm-button-row {
                margin-bottom: 15px;
                padding: 15px;
                border: 1px solid #ddd;
                border-radius: 4px;
                background: #f9f9f9;
            }
            
            .hssm-button-fields label {
                display: inline-block;
                width: 100px;
                font-weight: 600;
                margin-top: 5px;
            }
            
            .hssm-button-fields input {
                margin-bottom: 8px;
                margin-left: 10px;
            }
            
            .hssm-remove-button {
                margin-top: 5px;
                color: #a00;
                border-color: #a00;
            }
            
            .hssm-remove-button:hover {
                background: #a00;
                color: #fff;
            }
        </style>
        
        <script type="text/javascript">
            jQuery(document).ready(function($) {
                let buttonIndex = <?php echo count( $buttons ); ?>;
                const maxButtons = 5;
                
                // Add button functionality
                $('#hssm-add-button').on('click', function() {
                    if ($('.hssm-button-row').length >= maxButtons) {
                        alert('<?php _e( 'Maximum 5 buttons allowed', 'hi-school-slide-manager' ); ?>');
                        return;
                    }
                    
                    const newRow = `
                        <div class="hssm-button-row" data-index="${buttonIndex}">
                            <div class="hssm-button-fields">
                                <label><?php _e( 'Button Text:', 'hi-school-slide-manager' ); ?></label>
                                <input type="text" name="hssm_buttons[${buttonIndex}][text]" value="Learn More" class="regular-text" placeholder="Learn More" />
                                
                                <label><?php _e( 'Button URL:', 'hi-school-slide-manager' ); ?></label>
                                <input type="url" name="hssm_buttons[${buttonIndex}][url]" value="" class="regular-text" placeholder="https://example.com" />
                                
                                <button type="button" class="button hssm-remove-button"><?php _e( 'Remove', 'hi-school-slide-manager' ); ?></button>
                            </div>
                        </div>
                    `;
                    
                    $('#hssm-buttons-container').append(newRow);
                    buttonIndex++;
                    
                    // Show remove buttons if we have more than 1
                    if ($('.hssm-button-row').length > 1) {
                        $('.hssm-remove-button').show();
                    }
                    
                    // Hide add button if we've reached the maximum
                    if ($('.hssm-button-row').length >= maxButtons) {
                        $('#hssm-add-button').hide();
                    }
                });
                
                // Remove button functionality
                $(document).on('click', '.hssm-remove-button', function() {
                    $(this).closest('.hssm-button-row').remove();
                    
                    // Hide remove buttons if we only have 1 left
                    if ($('.hssm-button-row').length <= 1) {
                        $('.hssm-remove-button').hide();
                    }
                    
                    // Show add button if we're under the maximum
                    if ($('.hssm-button-row').length < maxButtons) {
                        $('#hssm-add-button').show();
                    }
                });
            });
        </script>
        <?php
    }
    
    /**
     * Render background image help meta box
     * 
     * @since 1.0.0
     * @param WP_Post $post Current post object
     */
    public function background_image_help_meta_box( $post ) {
        ?>
        <div class="hssm-background-help">
            <h4><?php _e( 'Background Image Requirements:', 'hi-school-slide-manager' ); ?></h4>
            <ul>
                <li><?php _e( 'Recommended size: 1920x800px or larger', 'hi-school-slide-manager' ); ?></li>
                <li><?php _e( 'Aspect ratio: 16:9 or similar wide format', 'hi-school-slide-manager' ); ?></li>
                <li><?php _e( 'Format: JPG, PNG, or WebP', 'hi-school-slide-manager' ); ?></li>
                <li><?php _e( 'File size: Under 1MB for best performance', 'hi-school-slide-manager' ); ?></li>
            </ul>
            
            <h4><?php _e( 'Design Tips:', 'hi-school-slide-manager' ); ?></h4>
            <ul>
                <li><?php _e( 'Keep important content away from edges', 'hi-school-slide-manager' ); ?></li>
                <li><?php _e( 'Ensure good contrast for text overlay', 'hi-school-slide-manager' ); ?></li>
                <li><?php _e( 'Consider mobile viewing (image will be cropped)', 'hi-school-slide-manager' ); ?></li>
            </ul>
            
            <p><strong><?php _e( 'Note:', 'hi-school-slide-manager' ); ?></strong> <?php _e( 'This image will be used as a full-width background for the header slide on the selected companion sites.', 'hi-school-slide-manager' ); ?></p>
        </div>
        
        <style>
            .hssm-background-help ul {
                margin-left: 20px;
            }
            .hssm-background-help li {
                margin-bottom: 5px;
                font-size: 13px;
            }
            .hssm-background-help h4 {
                margin-bottom: 8px;
                margin-top: 15px;
                color: #23282d;
            }
            .hssm-background-help h4:first-child {
                margin-top: 0;
            }
        </style>
        <?php
    }
    
    /**
     * Render slide scheduling meta box
     * 
     * @since 1.0.0
     * @param WP_Post $post Current post object
     */
    public function slide_scheduling_meta_box( $post ) {
        $start_date = get_post_meta( $post->ID, '_hssm_start_date', true );
        $end_date = get_post_meta( $post->ID, '_hssm_end_date', true );
        $auto_publish = get_post_meta( $post->ID, '_hssm_auto_publish', true );
        $auto_unpublish = get_post_meta( $post->ID, '_hssm_auto_unpublish', true );
        
        ?>
        <p>
            <label for="hssm_start_date"><strong><?php _e( 'Start Date', 'hi-school-slide-manager' ); ?></strong></label><br>
            <input type="datetime-local" id="hssm_start_date" name="hssm_start_date" value="<?php echo esc_attr( $start_date ); ?>" style="width: 100%;" />
        </p>
        <p>
            <label for="hssm_end_date"><strong><?php _e( 'End Date', 'hi-school-slide-manager' ); ?></strong></label><br>
            <input type="datetime-local" id="hssm_end_date" name="hssm_end_date" value="<?php echo esc_attr( $end_date ); ?>" style="width: 100%;" />
        </p>
        <p>
            <label>
                <input type="checkbox" name="hssm_auto_publish" value="1" <?php checked( $auto_publish, '1' ); ?> />
                <?php _e( 'Auto-publish on start date', 'hi-school-slide-manager' ); ?>
            </label>
        </p>
        <p>
            <label>
                <input type="checkbox" name="hssm_auto_unpublish" value="1" <?php checked( $auto_unpublish, '1' ); ?> />
                <?php _e( 'Auto-unpublish on end date', 'hi-school-slide-manager' ); ?>
            </label>
        </p>
        <?php
    }
    
    /**
     * Render slide targeting meta box
     * 
     * @since 1.0.0
     * @param WP_Post $post Current post object
     */
    public function slide_targeting_meta_box( $post ) {
        // Get current terms
        $current_sites = wp_get_post_terms( $post->ID, self::SITE_TAXONOMY, array( 'fields' => 'ids' ) );
        $current_clients = wp_get_post_terms( $post->ID, self::CLIENT_TAXONOMY, array( 'fields' => 'ids' ) );
        
        // Get all available site terms
        $site_terms = get_terms( array(
            'taxonomy' => self::SITE_TAXONOMY,
            'hide_empty' => false,
        ) );
        
        // Get all available client terms
        $client_terms = get_terms( array(
            'taxonomy' => self::CLIENT_TAXONOMY,
            'hide_empty' => false,
        ) );
        
        ?>
        <div class="hssm-targeting-section">
            <p><strong><?php _e( 'Target Sites', 'hi-school-slide-manager' ); ?></strong></p>
            <?php if ( ! empty( $site_terms ) && ! is_wp_error( $site_terms ) ) : ?>
                <?php foreach ( $site_terms as $term ) : ?>
                    <p>
                        <label>
                            <input type="checkbox" name="hssm_target_sites[]" value="<?php echo esc_attr( $term->term_id ); ?>" <?php checked( in_array( $term->term_id, $current_sites ) ); ?> />
                            <?php echo esc_html( $term->name ); ?>
                        </label>
                        <?php if ( $term->description ) : ?>
                            <br><small class="description"><?php echo esc_html( $term->description ); ?></small>
                        <?php endif; ?>
                    </p>
                <?php endforeach; ?>
            <?php else : ?>
                <p class="description"><?php _e( 'No sites available. Sites will be created automatically.', 'hi-school-slide-manager' ); ?></p>
            <?php endif; ?>
        </div>
        
        <div class="hssm-targeting-section" style="margin-top: 20px; padding-top: 15px; border-top: 1px solid #ddd;">
            <p><strong><?php _e( 'Client (Optional)', 'hi-school-slide-manager' ); ?></strong></p>
            <?php if ( ! empty( $client_terms ) && ! is_wp_error( $client_terms ) ) : ?>
                <select name="hssm_client" style="width: 100%;">
                    <option value=""><?php _e( 'Select a client (optional)', 'hi-school-slide-manager' ); ?></option>
                    <?php foreach ( $client_terms as $term ) : ?>
                        <option value="<?php echo esc_attr( $term->term_id ); ?>" <?php selected( in_array( $term->term_id, $current_clients ) ); ?>>
                            <?php echo esc_html( $term->name ); ?>
                        </option>
                    <?php endforeach; ?>
                </select>
            <?php else : ?>
                <p class="description">
                    <?php _e( 'No clients available.', 'hi-school-slide-manager' ); ?>
                    <a href="<?php echo admin_url( 'edit-tags.php?taxonomy=' . self::CLIENT_TAXONOMY . '&post_type=' . self::POST_TYPE ); ?>">
                        <?php _e( 'Add clients here', 'hi-school-slide-manager' ); ?>
                    </a>
                </p>
            <?php endif; ?>
        </div>
        
        <style>
            .hssm-targeting-section label {
                display: flex;
                align-items: flex-start;
                gap: 8px;
            }
            .hssm-targeting-section input[type="checkbox"] {
                margin: 0;
                flex-shrink: 0;
            }
        </style>
        <?php
    }
    
    /**
     * Save meta field data
     * 
     * @since 1.0.0
     * @param int $post_id Post ID
     */
    public function save_meta_fields( $post_id ) {
        // Verify nonce
        if ( ! isset( $_POST['hssm_slide_meta_nonce'] ) || ! wp_verify_nonce( $_POST['hssm_slide_meta_nonce'], 'hssm_save_slide_meta' ) ) {
            return;
        }
        
        // Check if this is an autosave
        if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
            return;
        }
        
        // Check post type
        if ( get_post_type( $post_id ) !== self::POST_TYPE ) {
            return;
        }
        
        // Check permissions
        if ( ! current_user_can( 'edit_post', $post_id ) ) {
            return;
        }
        
        // Save meta fields
        $meta_fields = array(
            'hssm_subtitle' => 'sanitize_text_field',
            'hssm_order' => 'intval',
            'hssm_start_date' => 'sanitize_text_field',
            'hssm_end_date' => 'sanitize_text_field',
        );
        
        foreach ( $meta_fields as $field => $sanitize_function ) {
            if ( isset( $_POST[ $field ] ) ) {
                $value = call_user_func( $sanitize_function, $_POST[ $field ] );
                update_post_meta( $post_id, '_' . $field, $value );
            }
        }
        
        // Save buttons array
        if ( isset( $_POST['hssm_buttons'] ) && is_array( $_POST['hssm_buttons'] ) ) {
            $buttons = array();
            foreach ( $_POST['hssm_buttons'] as $button_data ) {
                if ( ! empty( $button_data['text'] ) || ! empty( $button_data['url'] ) ) {
                    $buttons[] = array(
                        'text' => sanitize_text_field( $button_data['text'] ),
                        'url' => esc_url_raw( $button_data['url'] )
                    );
                }
            }
            // Limit to 5 buttons maximum
            $buttons = array_slice( $buttons, 0, 5 );
            update_post_meta( $post_id, '_hssm_buttons', $buttons );
        } else {
            // If no buttons, set default
            update_post_meta( $post_id, '_hssm_buttons', array(
                array( 'text' => 'Learn More', 'url' => '' )
            ) );
        }
        
        // Save checkbox fields
        $checkbox_fields = array( 'hssm_auto_publish', 'hssm_auto_unpublish', 'hssm_hide_all_text' );
        foreach ( $checkbox_fields as $field ) {
            $value = isset( $_POST[ $field ] ) ? '1' : '0';
            update_post_meta( $post_id, '_' . $field, $value );
        }
        
        // Save target sites taxonomy
        if ( isset( $_POST['hssm_target_sites'] ) && is_array( $_POST['hssm_target_sites'] ) ) {
            $target_sites = array_map( 'intval', $_POST['hssm_target_sites'] );
            wp_set_post_terms( $post_id, $target_sites, self::SITE_TAXONOMY );
        } else {
            wp_set_post_terms( $post_id, array(), self::SITE_TAXONOMY );
        }
        
        // Save client taxonomy
        if ( isset( $_POST['hssm_client'] ) && ! empty( $_POST['hssm_client'] ) ) {
            $client_id = intval( $_POST['hssm_client'] );
            wp_set_post_terms( $post_id, array( $client_id ), self::CLIENT_TAXONOMY );
        } else {
            wp_set_post_terms( $post_id, array(), self::CLIENT_TAXONOMY );
        }
        
        // Send email notification for new slides
        if ( get_post_status( $post_id ) === 'publish' && ! get_post_meta( $post_id, '_hssm_notification_sent', true ) ) {
            $this->send_new_slide_notification( $post_id );
            update_post_meta( $post_id, '_hssm_notification_sent', '1' );
        }
    }
    
    /**
     * Add custom columns to the slides list table
     * 
     * @since 1.0.0
     * @param array $columns Current columns
     * @return array Modified columns
     */
    public function add_custom_columns( $columns ) {
        $new_columns = array();
        $new_columns['cb'] = $columns['cb'];
        $new_columns['title'] = $columns['title'];
        $new_columns['target_sites'] = __( 'Target Sites', 'hi-school-slide-manager' );
        $new_columns['client'] = __( 'Client', 'hi-school-slide-manager' );
        $new_columns['schedule'] = __( 'Schedule', 'hi-school-slide-manager' );
        $new_columns['order'] = __( 'Order', 'hi-school-slide-manager' );
        $new_columns['date'] = $columns['date'];
        
        return $new_columns;
    }
    
    /**
     * Display custom column content
     * 
     * @since 1.0.0
     * @param string $column Column name
     * @param int $post_id Post ID
     */
    public function custom_column_content( $column, $post_id ) {
        switch ( $column ) {
            case 'title':
                // Add drag handle to title column
                echo '<span class="hssm-drag-handle dashicons dashicons-menu" title="' . esc_attr__( 'Drag to reorder', 'hi-school-slide-manager' ) . '"></span>';
                break;
                
            case 'target_sites':
                $site_terms = wp_get_post_terms( $post_id, self::SITE_TAXONOMY );
                if ( ! empty( $site_terms ) && ! is_wp_error( $site_terms ) ) {
                    $site_names = wp_list_pluck( $site_terms, 'name' );
                    echo esc_html( implode( ', ', $site_names ) );
                } else {
                    echo '<em>' . __( 'No sites selected', 'hi-school-slide-manager' ) . '</em>';
                }
                break;
                
            case 'client':
                $client_terms = wp_get_post_terms( $post_id, self::CLIENT_TAXONOMY );
                if ( ! empty( $client_terms ) && ! is_wp_error( $client_terms ) ) {
                    echo esc_html( $client_terms[0]->name );
                } else {
                    echo '<em>' . __( 'No client', 'hi-school-slide-manager' ) . '</em>';
                }
                break;
                
            case 'schedule':
                $start_date = get_post_meta( $post_id, '_hssm_start_date', true );
                $end_date = get_post_meta( $post_id, '_hssm_end_date', true );
                
                if ( $start_date || $end_date ) {
                    echo '<div>';
                    if ( $start_date ) {
                        echo '<strong>' . __( 'Start:', 'hi-school-slide-manager' ) . '</strong> ' . esc_html( date( 'M j, Y g:i A', strtotime( $start_date ) ) ) . '<br>';
                    }
                    if ( $end_date ) {
                        echo '<strong>' . __( 'End:', 'hi-school-slide-manager' ) . '</strong> ' . esc_html( date( 'M j, Y g:i A', strtotime( $end_date ) ) );
                    }
                    echo '</div>';
                } else {
                    echo '<em>' . __( 'No schedule set', 'hi-school-slide-manager' ) . '</em>';
                }
                break;
                
            case 'order':
                $order = get_post_meta( $post_id, '_hssm_order', true );
                echo esc_html( $order ?: '0' );
                break;
        }
    }
    
    /**
     * Send email notification for new slide
     * 
     * @since 1.0.0
     * @param int $post_id Post ID
     */
    private function send_new_slide_notification( $post_id ) {
        $notification_emails = get_option( 'hssm_notification_emails', array() );
        
        if ( empty( $notification_emails ) ) {
            return;
        }
        
        $post = get_post( $post_id );
        $subject = sprintf( __( 'New Slide Created: %s', 'hi-school-slide-manager' ), $post->post_title );
        
        $message = sprintf(
            __( 'A new slide has been created and published on %s.' . "\n\n" .
                'Title: %s' . "\n" .
                'Content: %s' . "\n" .
                'Edit URL: %s', 'hi-school-slide-manager' ),
            get_bloginfo( 'name' ),
            $post->post_title,
            wp_strip_all_tags( $post->post_content ),
            admin_url( 'post.php?post=' . $post_id . '&action=edit' )
        );
        
        $headers = array( 'Content-Type: text/plain; charset=UTF-8' );
        
        foreach ( $notification_emails as $email ) {
            wp_mail( $email, $subject, $message, $headers );
        }
    }
    
    /**
     * Check for scheduled slides that need status updates
     * 
     * @since 1.0.0
     */
    public function check_scheduled_slides() {
        $current_time = current_time( 'mysql' );
        
        // Auto-publish slides that should start now
        $slides_to_publish = get_posts( array(
            'post_type' => self::POST_TYPE,
            'post_status' => 'draft',
            'meta_query' => array(
                'relation' => 'AND',
                array(
                    'key' => '_hssm_auto_publish',
                    'value' => '1',
                    'compare' => '='
                ),
                array(
                    'key' => '_hssm_start_date',
                    'value' => $current_time,
                    'compare' => '<='
                )
            ),
            'numberposts' => -1
        ) );
        
        foreach ( $slides_to_publish as $slide ) {
            wp_update_post( array(
                'ID' => $slide->ID,
                'post_status' => 'publish'
            ) );
        }
        
        // Auto-unpublish slides that should end now
        $slides_to_unpublish = get_posts( array(
            'post_type' => self::POST_TYPE,
            'post_status' => 'publish',
            'meta_query' => array(
                'relation' => 'AND',
                array(
                    'key' => '_hssm_auto_unpublish',
                    'value' => '1',
                    'compare' => '='
                ),
                array(
                    'key' => '_hssm_end_date',
                    'value' => $current_time,
                    'compare' => '<='
                )
            ),
            'numberposts' => -1
        ) );
        
        foreach ( $slides_to_unpublish as $slide ) {
            wp_update_post( array(
                'ID' => $slide->ID,
                'post_status' => 'draft'
            ) );
        }
    }
    
    /**
     * Enqueue admin scripts for drag-and-drop functionality
     * 
     * @since 1.0.0
     * @param string $hook Current admin page hook
     */
    public function enqueue_admin_scripts( $hook ) {
        global $post_type;
        
        if ( $hook === 'edit.php' && $post_type === self::POST_TYPE ) {
            wp_enqueue_script( 'jquery-ui-sortable' );
            wp_enqueue_script( 
                'hssm-admin-sortable', 
                HSSM_PLUGIN_URL . 'assets/js/admin-sortable.js', 
                array( 'jquery', 'jquery-ui-sortable' ), 
                HSSM_VERSION, 
                true 
            );
            
            wp_localize_script( 'hssm-admin-sortable', 'hssmAjax', array(
                'ajaxurl' => admin_url( 'admin-ajax.php' ),
                'nonce' => wp_create_nonce( 'hssm_update_slide_order' ),
                'postType' => self::POST_TYPE
            ) );
            
            // Add drag handle styles
            wp_add_inline_style( 'wp-admin', '
                .wp-list-table .hssm-drag-handle {
                    cursor: move;
                    color: #666;
                    margin-right: 5px;
                }
                .wp-list-table .hssm-drag-handle:hover {
                    color: #000;
                }
                .wp-list-table tbody tr.ui-sortable-helper {
                    background: #f0f0f0;
                    border: 2px dashed #0073aa;
                }
                .wp-list-table tbody tr.ui-sortable-placeholder {
                    background: #e0e0e0;
                    height: 40px;
                }
            ' );
        }
    }
    
    /**
     * AJAX handler for updating slide order
     * 
     * @since 1.0.0
     */
    public function ajax_update_slide_order() {
        // Verify nonce and permissions
        $nonce = isset( $_POST['nonce'] ) ? sanitize_text_field( wp_unslash( $_POST['nonce'] ) ) : '';
        if ( ! wp_verify_nonce( $nonce, 'hssm_update_slide_order' ) || ! current_user_can( 'edit_posts' ) ) {
            wp_send_json_error( 'Unauthorized' );
        }
        
        if ( isset( $_POST['slide_ids'] ) && is_array( $_POST['slide_ids'] ) ) {
            $slide_ids = array_map( 'intval', $_POST['slide_ids'] );
            
            foreach ( $slide_ids as $index => $slide_id ) {
                update_post_meta( $slide_id, '_hssm_order', $index );
            }
            
            wp_send_json_success( array( 'message' => __( 'Slide order updated successfully', 'hi-school-slide-manager' ) ) );
        }
        
        wp_send_json_error( array( 'message' => __( 'Failed to update slide order', 'hi-school-slide-manager' ) ) );
    }
}