<?php
/**
 * ThreeCal Admin
 *
 * Handles all admin functionality.
 *
 * @package ThreeCal
 * @since 1.0.0
 */

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

/**
 * Admin Class
 *
 * @since 1.0.0
 */
class ThreeCal_Admin {

    /**
     * Plugin name.
     *
     * @var string
     */
    private $plugin_name;

    /**
     * Version.
     *
     * @var string
     */
    private $version;

    /**
     * Current tab.
     *
     * @var string
     */
    private $current_tab = 'dashboard';

    /**
     * Constructor.
     *
     * @param string $plugin_name Plugin name.
     * @param string $version     Version.
     */
    public function __construct( $plugin_name, $version ) {
        $this->plugin_name = $plugin_name;
        $this->version = $version;

        // phpcs:disable WordPress.Security.NonceVerification.Recommended -- Only reading for tab display
        $this->current_tab = isset( $_GET['tab'] ) ? sanitize_key( wp_unslash( $_GET['tab'] ) ) : 'dashboard';
        // phpcs:enable WordPress.Security.NonceVerification.Recommended
    }

    /**
     * Enqueue admin styles
     */
    public function enqueue_styles($hook) {
        if (strpos($hook, '3task-calendar') === false) {
            return;
        }

        wp_enqueue_style('wp-color-picker');

        wp_enqueue_style(
            $this->plugin_name . '-admin',
            THREECAL_PLUGIN_URL . 'admin/css/admin.css',
            array(),
            threecal_asset_version('admin/css/admin.css')
        );
    }

    /**
     * Enqueue admin scripts
     */
    public function enqueue_scripts($hook) {
        if (strpos($hook, '3task-calendar') === false) {
            return;
        }

        wp_enqueue_media();
        wp_enqueue_script('wp-color-picker');

        wp_enqueue_script(
            $this->plugin_name . '-admin',
            THREECAL_PLUGIN_URL . 'admin/js/admin.js',
            array('jquery', 'wp-color-picker'),
            threecal_asset_version('admin/js/admin.js'),
            true
        );

        wp_localize_script($this->plugin_name . '-admin', 'threecal_admin', array(
            'ajax_url' => admin_url('admin-ajax.php'),
            'admin_url' => admin_url(),
            'nonce' => wp_create_nonce('threecal_admin_nonce'),
            'strings' => array(
                'confirm_delete' => __('Are you sure you want to delete this item?', '3task-calendar'),
                'confirm_delete_multiple' => __('Are you sure you want to delete the selected items?', '3task-calendar'),
                'select_image' => __('Select Image', '3task-calendar'),
                'use_image' => __('Use Image', '3task-calendar'),
                'prefill_no_url' => __('Please enter the address first.', '3task-calendar'),
                'prefill_wait' => __('Reading the website …', '3task-calendar'),
                'prefill_error' => __('The website could not be read.', '3task-calendar'),
                /* translators: %s: list of field names */
                'prefill_done' => __('Taken from the website: %s.', '3task-calendar'),
                'prefill_nothing_new' => __('All fields were already filled in, nothing changed.', '3task-calendar'),
                /* translators: %s: name and address of the location */
                'prefill_location' => __('Location on the website: %s. Add it under Locations and choose it here.', '3task-calendar'),
                /* translators: %s: image address */
                'prefill_image' => __('Image on the website: %s', '3task-calendar'),
                'saving' => __('Saving...', '3task-calendar'),
                'saved' => __('Saved!', '3task-calendar'),
                'error' => __('An error occurred.', '3task-calendar')
            )
        ));
    }

    /**
     * Add menu pages.
     */
    public function add_menu_pages() {
        add_menu_page(
            __( '3task Calendar', '3task-calendar' ),
            __( '3task Calendar', '3task-calendar' ),
            'edit_threecal_events',
            '3task-calendar',
            array( $this, 'render_admin_page' ),
            'dashicons-calendar-alt',
            26
        );
    }

    /**
     * Get available tabs.
     *
     * @return array Tabs configuration.
     */
    private function get_tabs() {
        $counts = $this->get_tab_counts();

        return array(
            'dashboard'  => array(
                'title' => __( 'Dashboard', '3task-calendar' ),
                'icon'  => 'layout-dashboard',
            ),
            'events'     => array(
                'title' => __( 'Events', '3task-calendar' ),
                'icon'  => 'calendar-event',
                'count' => $counts['events'],
            ),
            'categories' => array(
                'title' => __( 'Categories', '3task-calendar' ),
                'icon'  => 'category',
                'count' => $counts['categories'],
            ),
            'locations'  => array(
                'title' => __( 'Locations', '3task-calendar' ),
                'icon'  => 'map-pin',
                'count' => $counts['locations'],
            ),
            'posts'      => array(
                'title' => __( 'Posts', '3task-calendar' ),
                'icon'  => 'article',
            ),
            'import'     => array(
                'title' => __( 'Import', '3task-calendar' ),
                'icon'  => 'file-import',
            ),
            'design'     => array(
                'title' => __( 'Design', '3task-calendar' ),
                'icon'  => 'palette',
            ),
            'settings'   => array(
                'title' => __( 'Settings', '3task-calendar' ),
                'icon'  => 'settings',
            ),
            'help'       => array(
                'title' => __( 'Help', '3task-calendar' ),
                'icon'  => 'help-circle',
            ),
        );
    }

    /**
     * Counts for the tab badges.
     *
     * @return array
     */
    private function get_tab_counts() {
        global $wpdb;

        // phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Counts from custom tables.
        $events     = (int) $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}threecal_events WHERE parent_id IS NULL OR parent_id = 0" );
        $categories = (int) $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}threecal_categories" );
        $locations  = (int) $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}threecal_locations" );
        // phpcs:enable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching

        return compact( 'events', 'categories', 'locations' );
    }

    /**
     * Render main admin page with tabs.
     */
    public function render_admin_page() {
        $tabs = $this->get_tabs();
        ?>
        <div class="wrap threecal-wrap threecal-admin">
            <h1 class="screen-reader-text"><?php esc_html_e( '3task Calendar', '3task-calendar' ); ?></h1>

            <div class="threecal-admin-header">
                <div class="threecal-admin-header-left">
                    <div class="threecal-admin-icon"><?php ThreeCal_Icons::render( 'calendar-event', 34 ); ?></div>
                    <div class="threecal-admin-title">
                        <span class="threecal-admin-name"><?php esc_html_e( '3task Calendar', '3task-calendar' ); ?></span>
                        <span class="threecal-admin-meta">
                            <span class="threecal-admin-version"><?php echo esc_html( 'v' . THREECAL_VERSION ); ?></span>
                            <span class="threecal-admin-status"><?php esc_html_e( 'Active', '3task-calendar' ); ?></span>
                        </span>
                    </div>
                </div>
                <div class="threecal-admin-header-right">
                    <a class="threecal-admin-header-btn" href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=help' ) ); ?>">
                        <?php ThreeCal_Icons::render( 'book', 16 ); ?>
                        <?php esc_html_e( 'Documentation', '3task-calendar' ); ?>
                    </a>
                    <a class="threecal-admin-header-btn" href="https://wordpress.org/support/plugin/3task-calendar/" target="_blank" rel="noopener">
                        <?php ThreeCal_Icons::render( 'message-circle', 16 ); ?>
                        <?php esc_html_e( 'Support', '3task-calendar' ); ?>
                    </a>
                </div>
            </div>

            <nav class="threecal-admin-tabs" aria-label="<?php esc_attr_e( '3task Calendar', '3task-calendar' ); ?>">
                <?php foreach ( $tabs as $tab_key => $tab ) : ?>
                    <?php $active = ( $this->current_tab === $tab_key ); ?>
                    <a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=' . $tab_key ) ); ?>"
                       class="threecal-admin-tab<?php echo $active ? ' is-active' : ''; ?>"
                       <?php echo $active ? 'aria-current="page"' : ''; ?>>
                        <?php ThreeCal_Icons::render( $tab['icon'], 18 ); ?>
                        <span><?php echo esc_html( $tab['title'] ); ?></span>
                        <?php if ( ! empty( $tab['count'] ) ) : ?>
                            <span class="threecal-admin-badge"><?php echo esc_html( $tab['count'] ); ?></span>
                        <?php endif; ?>
                    </a>
                <?php endforeach; ?>
            </nav>

            <div class="threecal-tab-content threecal-admin-content">
                <?php $this->render_tab_content(); ?>
            </div>
        </div>
        <?php
    }

    /**
     * Render tab content.
     */
    private function render_tab_content() {
        switch ( $this->current_tab ) {
            case 'events':
                $this->render_events();
                break;
            case 'categories':
                $this->render_categories();
                break;
            case 'locations':
                $this->render_locations();
                break;
            case 'design':
                $this->render_design();
                break;
            case 'posts':
                ThreeCal_Post_Dates::render_settings_page();
                break;
            case 'import':
                $this->render_import();
                break;
            case 'settings':
                $this->render_settings();
                break;
            case 'help':
                $this->render_help();
                break;
            default:
                $this->render_dashboard();
        }
    }

    /**
     * Render dashboard tab.
     */
    private function render_dashboard() {
        $stats    = $this->get_event_stats();
        $counts   = $this->get_tab_counts();
        $upcoming = ThreeCal_Event::get_upcoming( 5 );
        $cats     = ThreeCal_Event::get_categories_for_events( wp_list_pluck( $upcoming, 'id' ) );
        $pending  = ThreeCal_Submit::pending_count();
        if ( $pending ) {
            echo '<div class="notice notice-info inline threecal-submitted-note"><p>' . esc_html( sprintf(
                /* translators: %s: number of submitted events */
                _n( '%s event was submitted by a visitor and waits for your check.', '%s events were submitted by visitors and wait for your check.', $pending, '3task-calendar' ),
                number_format_i18n( $pending )
            ) ) . ' <a href="' . esc_url( admin_url( 'admin.php?page=3task-calendar&tab=events&scope=submitted' ) ) . '">' . esc_html__( 'Show submitted events', '3task-calendar' ) . '</a></p></div>';
        }
        $new_url  = admin_url( 'admin.php?page=3task-calendar&tab=events&action=new' );
        ?>
        <?php if ( 0 === (int) $stats['total_events'] ) : ?>
        <div class="threecal-onboarding">
            <div class="threecal-onboarding-icon"><?php ThreeCal_Icons::render( 'calendar-plus', 28 ); ?></div>
            <div class="threecal-onboarding-text">
                <h2><?php esc_html_e( 'Welcome to 3task Calendar', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'Create and manage events for your WordPress website. Get started by creating your first event!', '3task-calendar' ); ?></p>
            </div>
            <a class="threecal-btn-primary" href="<?php echo esc_url( $new_url ); ?>"><?php ThreeCal_Icons::render( 'plus', 16 ); ?><?php esc_html_e( 'Create Your First Event', '3task-calendar' ); ?></a>
        </div>
        <?php endif; ?>

        <div class="threecal-kpis">
            <div class="threecal-kpi kpi-blue">
                <div class="threecal-kpi-head"><?php ThreeCal_Icons::render( 'calendar-event', 22 ); ?></div>
                <div class="threecal-kpi-value"><?php echo esc_html( $stats['total_events'] ); ?></div>
                <div class="threecal-kpi-label"><?php esc_html_e( 'Total Events', '3task-calendar' ); ?></div>
            </div>
            <div class="threecal-kpi kpi-green">
                <div class="threecal-kpi-head"><?php ThreeCal_Icons::render( 'calendar-check', 22 ); ?></div>
                <div class="threecal-kpi-value"><?php echo esc_html( $stats['published_events'] ); ?></div>
                <div class="threecal-kpi-label"><?php esc_html_e( 'Published Events', '3task-calendar' ); ?></div>
            </div>
            <div class="threecal-kpi kpi-orange">
                <div class="threecal-kpi-head"><?php ThreeCal_Icons::render( 'pencil-plus', 22 ); ?></div>
                <div class="threecal-kpi-value"><?php echo esc_html( $stats['draft_events'] ); ?></div>
                <div class="threecal-kpi-label"><?php esc_html_e( 'Draft Events', '3task-calendar' ); ?></div>
            </div>
            <div class="threecal-kpi kpi-teal">
                <div class="threecal-kpi-head"><?php ThreeCal_Icons::render( 'category', 22 ); ?></div>
                <div class="threecal-kpi-value"><?php echo esc_html( $counts['categories'] ); ?></div>
                <div class="threecal-kpi-label"><?php esc_html_e( 'Categories', '3task-calendar' ); ?></div>
            </div>
        </div>

        <div class="threecal-admin-grid">
            <section class="threecal-panel">
                <h2 class="threecal-panel-title"><?php ThreeCal_Icons::render( 'calendar-stats', 20 ); ?><?php esc_html_e( 'Upcoming Events', '3task-calendar' ); ?></h2>
                <?php if ( empty( $upcoming ) ) : ?>
                    <p class="threecal-muted"><?php esc_html_e( 'No upcoming events.', '3task-calendar' ); ?></p>
                <?php else : ?>
                <ul class="threecal-admin-upcoming">
                    <?php foreach ( $upcoming as $event ) :
                        $color = ThreeCal_Themes::event_color( $event, isset( $cats[ $event->id ] ) ? $cats[ $event->id ] : array() );
                        $start = strtotime( $event->start_date );
                        $edit  = admin_url( 'admin.php?page=3task-calendar&tab=events&action=edit&event=' . ( $event->parent_id ? $event->parent_id : $event->id ) );
                        $from  = is_array( $event->settings ) ? $event->settings : json_decode( (string) $event->settings, true );
                        if ( ! empty( $from['post_id'] ) && get_edit_post_link( (int) $from['post_id'] ) ) {
                            $edit = get_edit_post_link( (int) $from['post_id'], 'raw' );
                        }
                        ?>
                    <li style="<?php echo esc_attr( ThreeCal_Themes::event_style( $color ) ); ?>">
                        <span class="threecal-admin-date">
                            <span><?php echo esc_html( date_i18n( 'M', $start ) ); ?></span>
                            <strong><?php echo esc_html( date_i18n( $event->is_month_only() ? 'Y' : 'j', $start ) ); ?></strong>
                        </span>
                        <span class="threecal-admin-upcoming-text">
                            <a href="<?php echo esc_url( $edit ); ?>"><?php echo esc_html( $event->title ); ?></a>
                            <span class="threecal-muted">
                                <?php
                                if ( $event->is_month_only() ) {
                                    echo esc_html( $event->month_label() . ' · ' . ThreeCal_Event::tba_text() );
                                } else {
                                    echo esc_html( $event->all_day ? __( 'All day', '3task-calendar' ) : date_i18n( threecal_time_format(), $start ) );
                                }
                                ?>
                                <?php if ( $event->parent_id ) : ?> · <?php esc_html_e( 'Series', '3task-calendar' ); ?><?php endif; ?>
                            </span>
                        </span>
                    </li>
                    <?php endforeach; ?>
                </ul>
                <?php endif; ?>
            </section>

            <div class="threecal-admin-side">
                <section class="threecal-panel">
                    <h2 class="threecal-panel-title"><?php ThreeCal_Icons::render( 'layout-dashboard', 20 ); ?><?php esc_html_e( 'Quick Actions', '3task-calendar' ); ?></h2>
                    <div class="threecal-quick">
                        <a href="<?php echo esc_url( $new_url ); ?>"><span class="threecal-quick-icon"><?php ThreeCal_Icons::render( 'calendar-plus', 22 ); ?></span><?php esc_html_e( 'Add New Event', '3task-calendar' ); ?></a>
                        <a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=categories' ) ); ?>"><span class="threecal-quick-icon"><?php ThreeCal_Icons::render( 'category', 22 ); ?></span><?php esc_html_e( 'Categories', '3task-calendar' ); ?></a>
                        <a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=design' ) ); ?>"><span class="threecal-quick-icon"><?php ThreeCal_Icons::render( 'palette', 22 ); ?></span><?php esc_html_e( 'Choose design', '3task-calendar' ); ?></a>
                        <a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=help' ) ); ?>"><span class="threecal-quick-icon"><?php ThreeCal_Icons::render( 'book', 22 ); ?></span><?php esc_html_e( 'Shortcodes', '3task-calendar' ); ?></a>
                    </div>
                </section>

                <section class="threecal-panel threecal-panel-tint">
                    <span class="threecal-pill"><?php esc_html_e( 'Included for free', '3task-calendar' ); ?></span>
                    <ul class="threecal-feature-chips">
                        <li><?php ThreeCal_Icons::render( 'repeat', 16 ); ?><?php esc_html_e( 'Recurring events', '3task-calendar' ); ?></li>
                        <li><?php ThreeCal_Icons::render( 'calendar-plus', 16 ); ?><?php esc_html_e( 'iCal subscription', '3task-calendar' ); ?></li>
                        <li><?php ThreeCal_Icons::render( 'palette', 16 ); ?><?php esc_html_e( '4 designs', '3task-calendar' ); ?></li>
                        <li><?php ThreeCal_Icons::render( 'route', 16 ); ?><?php esc_html_e( 'Route without Google', '3task-calendar' ); ?></li>
                        <li><?php ThreeCal_Icons::render( 'calendar-check', 16 ); ?><?php esc_html_e( 'Event schema (SEO)', '3task-calendar' ); ?></li>
                    </ul>
                </section>
            </div>
        </div>
        <?php
    }

    /**
     * Render design tab: default design and accent color.
     */
    private function render_design() {
        if ( ! current_user_can( 'threecal_settings' ) ) {
            echo '<div class="notice notice-error"><p>' . esc_html__( 'You do not have permission to change the calendar settings.', '3task-calendar' ) . '</p></div>';
            return;
        }

        $themes = ThreeCal_Themes::all();

        if ( isset( $_POST['threecal_save_design'] ) ) {
            check_admin_referer( 'threecal_design' );
            $settings = (array) get_option( 'threecal_settings', array() );
            $theme    = isset( $_POST['default_theme'] ) ? sanitize_key( wp_unslash( $_POST['default_theme'] ) ) : 'default';
            $settings['default_theme'] = isset( $themes[ $theme ] ) ? $theme : 'default';
            $accent   = isset( $_POST['accent_color'] ) ? sanitize_hex_color( wp_unslash( $_POST['accent_color'] ) ) : '';
            $settings['accent_color']  = $accent ? $accent : '';
            update_option( 'threecal_settings', $settings );
            echo '<div class="notice notice-success"><p>' . esc_html__( 'Settings saved!', '3task-calendar' ) . '</p></div>';
        }

        $current  = ThreeCal_Themes::normalize( '' );
        $settings = (array) get_option( 'threecal_settings', array() );
        $accent   = isset( $settings['accent_color'] ) ? $settings['accent_color'] : '';
        $renderer = new ThreeCal_Calendar_Renderer();
        wp_enqueue_style( 'threecal-public', THREECAL_PLUGIN_URL . 'public/css/threecal.css', array(), threecal_asset_version( 'public/css/threecal.css' ) );
        wp_enqueue_style( 'threecal-mini', THREECAL_PLUGIN_URL . 'public/css/threecal-mini.css', array(), threecal_asset_version( 'public/css/threecal-mini.css' ) );
        ?>
        <form method="post" class="threecal-design-form">
            <?php wp_nonce_field( 'threecal_design' ); ?>
            <section class="threecal-panel">
                <h2 class="threecal-panel-title"><?php ThreeCal_Icons::render( 'palette', 20 ); ?><?php esc_html_e( 'Default design', '3task-calendar' ); ?></h2>
                <p class="threecal-muted"><?php esc_html_e( 'Used by every calendar without its own theme attribute. A single calendar can still use another design, e.g. [threecal theme="dark"].', '3task-calendar' ); ?></p>
                <p class="threecal-muted"><?php esc_html_e( 'Elements without own design, such as the mini calendar in the sidebar, take the design of the calendar on the same page.', '3task-calendar' ); ?></p>
                <div class="threecal-design-grid">
                    <?php foreach ( $themes as $key => $theme ) : ?>
                    <label class="threecal-design-option<?php echo $current === $key ? ' is-selected' : ''; ?>">
                        <input type="radio" name="default_theme" value="<?php echo esc_attr( $key ); ?>" <?php checked( $current, $key ); ?>>
                        <span class="threecal-design-preview">
                            <?php
                            // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- Escaped inside the renderer.
                            echo $renderer->render_mini_calendar( array( 'theme' => $key, 'show_nav' => false, 'show_today' => false ) );
                            ?>
                        </span>
                        <span class="threecal-design-name"><?php echo esc_html( $theme['label'] ); ?> <code><?php echo esc_html( $key ); ?></code></span>
                        <span class="threecal-design-desc"><?php echo esc_html( $theme['description'] ); ?></span>
                    </label>
                    <?php endforeach; ?>
                </div>
            </section>

            <section class="threecal-panel">
                <h2 class="threecal-panel-title"><?php ThreeCal_Icons::render( 'palette', 20 ); ?><?php esc_html_e( 'Accent color', '3task-calendar' ); ?></h2>
                <p class="threecal-muted"><?php esc_html_e( 'Buttons, today marker and events without category color use this color. Leave empty to use the color of the design.', '3task-calendar' ); ?></p>
                <input type="text" name="accent_color" class="threecal-color-picker" value="<?php echo esc_attr( $accent ); ?>" data-default-color="">
                <p class="threecal-muted"><?php esc_html_e( 'Events take the color of their first category automatically.', '3task-calendar' ); ?></p>
            </section>

            <p><button type="submit" name="threecal_save_design" class="threecal-btn-primary"><?php esc_html_e( 'Save design', '3task-calendar' ); ?></button></p>
        </form>
        <?php
    }

    /**
     * Render events tab
     */
    private function render_events() {
        // Check if editing or creating an event.
        // phpcs:disable WordPress.Security.NonceVerification.Recommended -- Only reading for navigation, no data modification.
        if ( isset( $_GET['action'] ) && $_GET['action'] === 'edit' && isset( $_GET['event'] ) ) {
            // phpcs:enable WordPress.Security.NonceVerification.Recommended
            $this->render_edit_event();
            return;
        }

        // phpcs:disable WordPress.Security.NonceVerification.Recommended -- Only reading for navigation, no data modification.
        if ( isset( $_GET['action'] ) && $_GET['action'] === 'new' ) {
            // phpcs:enable WordPress.Security.NonceVerification.Recommended
            $this->render_new_event();
            return;
        }

        // List events (repetitions of a series are managed through their first event).
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Display filter only.
        $scope  = isset( $_GET['scope'] ) ? sanitize_key( wp_unslash( $_GET['scope'] ) ) : 'upcoming';
        $scope  = in_array( $scope, array( 'upcoming', 'past', 'all', 'submitted' ), true ) ? $scope : 'upcoming';
        /**
         * Filters the events shown in the admin list.
         *
         * @param array  $events Event rows.
         * @param string $scope  upcoming, past or all.
         */
        $events = apply_filters( 'threecal_admin_events', $this->get_events( $scope ), $scope );

        // Dates that come from posts are kept in the posts, not in this list.
        $from_posts = 0;
        foreach ( $events as $index => $row ) {
            $row_settings = json_decode( (string) $row->settings, true );
            if ( ! empty( $row_settings['post_id'] ) ) {
                $from_posts++;
                unset( $events[ $index ] );
            }
        }
        $events = array_values( $events );
        $row_settings_all = array();
        foreach ( $events as $row ) {
            $row_settings_all[ $row->id ] = json_decode( (string) $row->settings, true );
        }
        $cats   = ThreeCal_Event::get_categories_for_events( wp_list_pluck( $events, 'id' ) );
        $rules  = ThreeCal_Event::recurrence_options();
        $scopes = array(
            'upcoming' => __( 'Upcoming', '3task-calendar' ),
            'past'     => __( 'Past', '3task-calendar' ),
            'all'      => __( 'All', '3task-calendar' ),
        );
        $pending_count = ThreeCal_Submit::pending_count();
        if ( $pending_count || 'submitted' === $scope ) {
            /* translators: %s: number of submitted events */
            $scopes['submitted'] = sprintf( __( 'Submitted (%s)', '3task-calendar' ), number_format_i18n( $pending_count ) );
        }
        $status_labels = array(
            'published' => __( 'Published', '3task-calendar' ),
            'draft'     => __( 'Draft', '3task-calendar' ),
            'cancelled' => __( 'Cancelled', '3task-calendar' ),
        );
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Message param is for display only.
        $message = isset( $_GET['message'] ) ? sanitize_key( wp_unslash( $_GET['message'] ) ) : '';
        ?>
        <?php if ( $from_posts ) : ?>
        <div class="notice notice-info inline threecal-from-posts-note"><p>
            <?php
            /* translators: %s: number of dates */
            echo esc_html( sprintf( _n( '%s date comes from a post and is edited there:', '%s dates come from posts and are edited there:', $from_posts, '3task-calendar' ), number_format_i18n( $from_posts ) ) );
            foreach ( ThreeCal_Post_Dates::enabled_types() as $type_key => $type_settings ) {
                $type_object = get_post_type_object( $type_key );
                if ( $type_object ) {
                    echo ' <a href="' . esc_url( admin_url( 'edit.php?post_type=' . $type_key . '&orderby=threecal_date&order=asc' ) ) . '">' . esc_html( $type_object->labels->name ) . '</a>';
                }
            }
            ?>
        </p></div>
        <?php endif; ?>
        <?php if ( 'deleted' === $message ) : ?>
        <div class="notice notice-success is-dismissible"><p><?php esc_html_e( 'Event deleted.', '3task-calendar' ); ?></p></div>
        <?php elseif ( 'date_remove' === $message ) : ?>
        <div class="notice notice-success is-dismissible"><p><?php esc_html_e( 'The date was removed from the series.', '3task-calendar' ); ?></p></div>
        <?php endif; ?>
        <div class="threecal-list-toolbar">
            <div class="threecal-segmented" role="group" aria-label="<?php esc_attr_e( 'Filter', '3task-calendar' ); ?>">
                <?php foreach ( $scopes as $key => $label ) : ?>
                <a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=events&scope=' . $key ) ); ?>" class="<?php echo $scope === $key ? 'is-active' : ''; ?>"<?php echo $scope === $key ? ' aria-current="page"' : ''; ?>><?php echo esc_html( $label ); ?></a>
                <?php endforeach; ?>
            </div>
            <a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=events&action=new' ) ); ?>" class="threecal-btn-primary">
                <?php ThreeCal_Icons::render( 'plus', 16 ); ?>
                <?php esc_html_e( 'Add New Event', '3task-calendar' ); ?>
            </a>
        </div>

        <?php if ( empty( $events ) ) : ?>
            <div class="threecal-empty">
                <?php ThreeCal_Icons::render( 'calendar-plus', 40 ); ?>
                <p><?php esc_html_e( 'No events found. Create your first event to get started!', '3task-calendar' ); ?></p>
            </div>
        <?php else : ?>
            <ul class="threecal-event-rows">
                <?php foreach ( $events as $row ) :
                    $event    = new ThreeCal_Event( $row );
                    $ecats    = isset( $cats[ $event->id ] ) ? $cats[ $event->id ] : array();
                    $color    = ThreeCal_Themes::event_color( $event, $ecats );
                    $start    = strtotime( $event->start_date );
                    $edit_url = admin_url( 'admin.php?page=3task-calendar&tab=events&action=edit&event=' . $event->id );
                    $del_url  = wp_nonce_url( admin_url( 'admin.php?page=3task-calendar&tab=events&action=delete&id=' . $event->id ), 'threecal_delete_' . $event->id );
                    ?>
                <li class="threecal-event-row status-<?php echo esc_attr( $event->status ); ?>" style="<?php echo esc_attr( ThreeCal_Themes::event_style( $color ) ); ?>">
                    <span class="threecal-admin-date">
                        <span><?php echo esc_html( date_i18n( 'M', $start ) ); ?></span>
                        <strong><?php echo esc_html( date_i18n( $event->is_month_only() ? 'Y' : 'j', $start ) ); ?></strong>
                    </span>
                    <span class="threecal-event-row-main">
                        <a class="threecal-event-row-title" href="<?php echo esc_url( $edit_url ); ?>"><?php echo esc_html( $event->title ); ?></a>
                        <?php if ( ! empty( $row_settings_all[ $event->id ][ ThreeCal_Submit::KEY ] ) ) : ?><span class="threecal-badge threecal-badge-submitted"><?php esc_html_e( 'Submitted', '3task-calendar' ); ?></span><?php endif; ?>
                        <span class="threecal-event-row-meta">
                            <?php if ( $event->is_month_only() ) : ?>
                            <span><?php ThreeCal_Icons::render( 'calendar-question', 14 ); ?><?php echo esc_html( $event->month_label() . ' · ' . ThreeCal_Event::tba_text() ); ?></span>
                            <?php else : ?>
                            <span><?php ThreeCal_Icons::render( 'clock', 14 ); ?><?php echo esc_html( date_i18n( threecal_date_format(), $start ) . ( $event->all_day ? ' · ' . __( 'All day', '3task-calendar' ) : ' · ' . date_i18n( threecal_time_format(), $start ) ) ); ?></span>
                            <?php endif; ?>
                            <?php if ( ! empty( $event->recurrence_rule ) && isset( $rules[ $event->recurrence_rule ] ) ) : ?>
                            <span class="threecal-series-badge"><?php ThreeCal_Icons::render( 'repeat', 12 ); ?><?php echo esc_html( $rules[ $event->recurrence_rule ] ); ?><?php if ( $event->recurrence_end ) : ?>, <?php echo esc_html( sprintf( /* translators: %s: end date of a series */ __( 'until %s', '3task-calendar' ), date_i18n( threecal_date_format(), strtotime( $event->recurrence_end ) ) ) ); ?><?php endif; ?></span>
                            <?php endif; ?>
                            <?php foreach ( $ecats as $cat ) : ?>
                            <span class="threecal-cat-chip" style="<?php echo esc_attr( ThreeCal_Themes::event_style( sanitize_hex_color( (string) $cat->color ) ) ); ?>"><?php echo esc_html( $cat->name ); ?></span>
                            <?php endforeach; ?>
                        </span>
                    </span>
                    <span class="threecal-status threecal-status-<?php echo esc_attr( $event->status ); ?>"><?php echo esc_html( isset( $status_labels[ $event->status ] ) ? $status_labels[ $event->status ] : $event->status ); ?></span>
                    <span class="threecal-event-row-actions">
                        <a class="threecal-icon-btn" href="<?php echo esc_url( $edit_url ); ?>" aria-label="<?php echo esc_attr( sprintf( /* translators: %s: event title */ __( 'Edit %s', '3task-calendar' ), $event->title ) ); ?>"><?php ThreeCal_Icons::render( 'pencil-plus', 18 ); ?></a>
                        <a class="threecal-icon-btn is-danger" href="<?php echo esc_url( $del_url ); ?>" aria-label="<?php echo esc_attr( sprintf( /* translators: %s: event title */ __( 'Delete %s', '3task-calendar' ), $event->title ) ); ?>" onclick="return confirm('<?php echo esc_js( __( 'Are you sure you want to delete this event?', '3task-calendar' ) ); ?>');"><?php ThreeCal_Icons::render( 'x', 18 ); ?></a>
                    </span>
                </li>
                <?php endforeach; ?>
            </ul>
        <?php endif; ?>
        <?php
    }

    /**
     * Render categories tab
     */
    private function render_categories() {
        // Use the categories view which has the form built-in
        include THREECAL_PLUGIN_DIR . 'admin/views/categories.php';
    }

    /**
     * Render locations tab
     */
    private function render_locations() {
        // Use the locations view which has the form built-in
        include THREECAL_PLUGIN_DIR . 'admin/views/locations.php';
    }

    /**
     * Render settings tab
     */
    private function render_settings() {
        if ( ! current_user_can( 'threecal_settings' ) ) {
            echo '<div class="notice notice-error"><p>' . esc_html__( 'You do not have permission to change the calendar settings.', '3task-calendar' ) . '</p></div>';
            return;
        }

        if ( isset( $_POST['submit'] ) ) {
            check_admin_referer( 'threecal_settings' );

            // Merge with the stored settings so fields that are not part of this form stay untouched.
            $settings = (array) get_option( 'threecal_settings', array() );

            $settings['date_format']              = isset( $_POST['date_format'] ) ? sanitize_text_field( wp_unslash( $_POST['date_format'] ) ) : '';
            $settings['time_format']              = isset( $_POST['time_format'] ) ? sanitize_text_field( wp_unslash( $_POST['time_format'] ) ) : '';
            $settings['week_starts_on']           = ( isset( $_POST['week_starts_on'] ) && 0 === absint( $_POST['week_starts_on'] ) ) ? 0 : 1;
            $settings['show_event_time']          = ! empty( $_POST['show_event_time'] );
            $settings['show_event_location']      = ! empty( $_POST['show_event_location'] );
            $settings['enable_schema']            = ! empty( $_POST['enable_schema'] );
            $settings['external_links']           = ( isset( $_POST['external_links'] ) && 'follow' === $_POST['external_links'] ) ? 'follow' : 'nofollow';
            $settings['ics_reminder']             = isset( $_POST['ics_reminder'] ) && in_array( absint( $_POST['ics_reminder'] ), self::reminder_choices_minutes(), true ) ? absint( $_POST['ics_reminder'] ) : 0;
            $settings['submit_category']          = isset( $_POST['submit_category'] ) ? absint( $_POST['submit_category'] ) : 0;
            $settings['submit_notify']            = ! empty( $_POST['submit_notify'] );
            $settings['delete_data_on_uninstall'] = ! empty( $_POST['delete_data_on_uninstall'] );

            update_option( 'threecal_settings', $settings );
            echo '<div class="notice notice-success"><p>' . esc_html__( 'Settings saved!', '3task-calendar' ) . '</p></div>';
        }

        $settings = wp_parse_args(
            (array) get_option( 'threecal_settings', array() ),
            array(
                'date_format'              => '',
                'time_format'              => '',
                'week_starts_on'           => 1,
                'show_event_time'          => true,
                'show_event_location'      => true,
                'enable_schema'            => true,
                'external_links'           => 'nofollow',
                'ics_reminder'             => 0,
                'submit_category'          => 0,
                'submit_notify'            => true,
                'delete_data_on_uninstall' => false,
            )
        );
        ?>
        <form method="post">
            <?php wp_nonce_field('threecal_settings'); ?>
            
            <div class="threecal-card">
                <h3><?php esc_html_e( 'General Settings', '3task-calendar' ); ?></h3>
                
                <table class="form-table">
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Date Format', '3task-calendar' ); ?></th>
                        <td>
                            <input type="text" name="date_format" value="<?php echo esc_attr($settings['date_format']); ?>" placeholder="<?php echo esc_attr( get_option( 'date_format' ) ); ?>" class="regular-text" />
                            <p class="description"><?php esc_html_e( 'Leave empty to use the date format from the WordPress settings.', '3task-calendar' ); ?> <?php /* translators: %s: example date or time */ printf( esc_html__( 'Currently: %s', '3task-calendar' ), esc_html( date_i18n( threecal_date_format() ) ) ); ?></p>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Time Format', '3task-calendar' ); ?></th>
                        <td>
                            <input type="text" name="time_format" value="<?php echo esc_attr($settings['time_format']); ?>" placeholder="<?php echo esc_attr( get_option( 'time_format' ) ); ?>" class="regular-text" />
                            <p class="description"><?php esc_html_e( 'Leave empty to use the time format from the WordPress settings.', '3task-calendar' ); ?> <?php /* translators: %s: example date or time */ printf( esc_html__( 'Currently: %s', '3task-calendar' ), esc_html( date_i18n( threecal_time_format() ) ) ); ?></p>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Week Starts On', '3task-calendar' ); ?></th>
                        <td>
                            <select name="week_starts_on">
                                <option value="0" <?php selected($settings['week_starts_on'], 0); ?>><?php esc_html_e( 'Sunday', '3task-calendar' ); ?></option>
                                <option value="1" <?php selected($settings['week_starts_on'], 1); ?>><?php esc_html_e( 'Monday', '3task-calendar' ); ?></option>
                            </select>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Show Event Time', '3task-calendar' ); ?></th>
                        <td>
                            <input type="checkbox" name="show_event_time" value="1" <?php checked($settings['show_event_time']); ?> />
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Show Event Location', '3task-calendar' ); ?></th>
                        <td>
                            <input type="checkbox" name="show_event_location" value="1" <?php checked($settings['show_event_location']); ?> />
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Event Schema (SEO)', '3task-calendar' ); ?></th>
                        <td>
                            <label>
                                <input type="checkbox" name="enable_schema" value="1" <?php checked($settings['enable_schema']); ?> />
                                <?php esc_html_e( 'Add Schema.org event markup to pages with a calendar.', '3task-calendar' ); ?>
                            </label>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Links to other websites', '3task-calendar' ); ?></th>
                        <td>
                            <label><input type="radio" name="external_links" value="nofollow" <?php checked( $settings['external_links'], 'nofollow' ); ?> /> <?php esc_html_e( 'nofollow (recommended): search engines do not count them as your recommendation', '3task-calendar' ); ?></label><br>
                            <label><input type="radio" name="external_links" value="follow" <?php checked( $settings['external_links'], 'follow' ); ?> /> <?php esc_html_e( 'follow: treat every link like your own recommendation', '3task-calendar' ); ?></label>
                            <p class="description"><?php esc_html_e( 'Applies to the link of an event to its website. Single categories can be set to follow in the category form, for example partners that link back to you. Links open in a new window.', '3task-calendar' ); ?></p>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Reminder in the calendar file', '3task-calendar' ); ?></th>
                        <td>
                            <select name="ics_reminder">
                                <?php foreach ( self::reminder_choices() as $minutes => $label ) : ?>
                                <option value="<?php echo esc_attr( $minutes ); ?>" <?php selected( (int) $settings['ics_reminder'], $minutes ); ?>><?php echo esc_html( $label ); ?></option>
                                <?php endforeach; ?>
                            </select>
                            <p class="description"><?php esc_html_e( 'Visitors who add an event to their own calendar get this reminder from their calendar app. Nothing is stored on your website.', '3task-calendar' ); ?></p>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Submitted events', '3task-calendar' ); ?></th>
                        <td>
                            <p><?php esc_html_e( 'Visitors can submit events through the shortcode [threecal_submit]. A submission is saved as a draft and appears nowhere until you publish it.', '3task-calendar' ); ?></p>
                            <label><?php esc_html_e( 'Category for submitted events', '3task-calendar' ); ?>
                                <select name="submit_category">
                                    <option value="0"><?php esc_html_e( '— None —', '3task-calendar' ); ?></option>
                                    <?php foreach ( ThreeCal_Category::get_all() as $cat ) : ?>
                                    <option value="<?php echo esc_attr( $cat->id ); ?>" <?php selected( (int) $settings['submit_category'], (int) $cat->id ); ?>><?php echo esc_html( $cat->name ); ?></option>
                                    <?php endforeach; ?>
                                </select>
                            </label><br>
                            <label><input type="checkbox" name="submit_notify" value="1" <?php checked( $settings['submit_notify'] ); ?> /> <?php echo esc_html( sprintf( /* translators: %s: admin e-mail address */ __( 'E-mail %s about every submission', '3task-calendar' ), get_option( 'admin_email' ) ) ); ?></label>
                            <p class="description"><?php esc_html_e( 'Spam protection without external services: a hidden field, a minimum time to fill the form, at most ten submissions per hour from one connection. No IP address is stored with an event.', '3task-calendar' ); ?></p>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e( 'Uninstall', '3task-calendar' ); ?></th>
                        <td>
                            <label>
                                <input type="checkbox" name="delete_data_on_uninstall" value="1" <?php checked($settings['delete_data_on_uninstall']); ?> />
                                <?php esc_html_e( 'Delete all events, categories, locations and settings when the plugin is deleted.', '3task-calendar' ); ?>
                            </label>
                        </td>
                    </tr>
                </table>
                
                <?php submit_button(); ?>
            </div>
        </form>

        <?php $this->render_schema_doktor(); ?>
        <?php $this->render_llms(); ?>
        <?php
    }

    /**
     * JSON feed and llms.txt block for AI search engines and developers. Since 1.7.0
     */
    private function render_llms() {
        $snippet = threecal()->llms_snippet();
        ?>
        <div class="threecal-card threecal-llms" id="threecal-llms">
            <h3><?php esc_html_e( 'For AI search and developers: events as JSON', '3task-calendar' ); ?></h3>
            <p><?php esc_html_e( 'Your upcoming events are available as a JSON feed, with dates and time zone, place, organizer, categories and the calendar file of every event. Pages with a calendar announce it in their head. ChatGPT, Perplexity, Google and apps can read it directly.', '3task-calendar' ); ?></p>
            <p><code><?php echo esc_html( ThreeCal_Feed::url() ); ?></code> <a href="<?php echo esc_url( ThreeCal_Feed::url() ); ?>" target="_blank" rel="noopener"><?php esc_html_e( 'Open', '3task-calendar' ); ?></a></p>
            <p class="description"><?php esc_html_e( 'Filters: ?category=slug or ID, ?from=YYYY-MM-DD, ?to=YYYY-MM-DD, ?day=YYYY-MM-DD (one day, past allowed), ?search=word (title, description, location, city), ?limit=200 (default 50). Answers are cached for 15 minutes.', '3task-calendar' ); ?></p>
            <h4><?php esc_html_e( 'Block for your llms.txt', '3task-calendar' ); ?></h4>
            <p class="description"><?php esc_html_e( 'An llms.txt in the root of your website tells AI search engines what matters on your site. WordPress does not create one by itself. Paste this block into your llms.txt, or create the file with it, so the events are found.', '3task-calendar' ); ?></p>
            <textarea class="large-text code" rows="5" readonly onclick="this.select()"><?php echo esc_textarea( $snippet ); ?></textarea>
        </div>
        <?php
    }

    /**
     * Schema check: which upcoming events get event markup and why not. Since 1.7.0
     */
    private function render_schema_doktor() {
        $rows   = threecal()->schema_report( 20 );
        $labels = ThreeCal::schema_reason_labels();
        $pages  = threecal()->calendar_pages( 5 );
        ?>
        <div class="threecal-card threecal-schema-doktor" id="threecal-schema-doktor">
            <h3><?php esc_html_e( 'Schema check: what Google sees', '3task-calendar' ); ?></h3>
            <p class="description"><?php esc_html_e( 'The event schema names the next five events that have a real place and a known day. This list shows the next 20 events, whether they get markup and why not.', '3task-calendar' ); ?></p>
            <?php if ( ! $rows ) : ?>
                <p><?php esc_html_e( 'No upcoming events.', '3task-calendar' ); ?></p>
            <?php else : ?>
            <table class="widefat striped">
                <thead><tr><th><?php esc_html_e( 'Event', '3task-calendar' ); ?></th><th><?php esc_html_e( 'Date', '3task-calendar' ); ?></th><th><?php esc_html_e( 'Event schema', '3task-calendar' ); ?></th></tr></thead>
                <tbody>
                <?php foreach ( $rows as $row ) : ?>
                    <tr>
                        <td><a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=events&action=edit&event=' . (int) $row['id'] ) ); ?>"><?php echo esc_html( $row['title'] ); ?></a></td>
                        <td><?php echo esc_html( $row['start'] ); ?></td>
                        <td>
                            <?php if ( $row['ok'] ) : ?>
                                <span class="threecal-schema-ok">&#10003; <?php /* translators: %d: place 1 to 5 */ echo esc_html( sprintf( __( 'Yes, place %d of 5', '3task-calendar' ), (int) $row['place'] ) ); ?></span>
                            <?php else : ?>
                                <span class="threecal-schema-no">&#10007; <?php echo esc_html( implode( '; ', array_map( function ( $k ) use ( $labels ) { return isset( $labels[ $k ] ) ? $labels[ $k ] : $k; }, $row['reasons'] ) ) ); ?></span>
                            <?php endif; ?>
                        </td>
                    </tr>
                <?php endforeach; ?>
                </tbody>
            </table>
            <?php endif; ?>
            <?php if ( $pages ) : ?>
            <p><?php esc_html_e( 'Check a page with Google:', '3task-calendar' ); ?>
                <?php foreach ( $pages as $i => $page ) : ?>
                    <?php echo $i ? ' · ' : ''; ?><a href="<?php echo esc_url( 'https://search.google.com/test/rich-results?url=' . rawurlencode( get_permalink( $page ) ) ); ?>" target="_blank" rel="noopener"><?php echo esc_html( get_the_title( $page ) ); ?></a>
                <?php endforeach; ?>
            </p>
            <p class="description"><?php esc_html_e( 'The Rich Results Test opens in a new tab and asks Google to fetch your page; nothing is sent from here.', '3task-calendar' ); ?></p>
            <?php endif; ?>
        </div>
        <?php
    }

    /**
     * Reminder choices for the calendar file: minutes before the event. Since 1.7.0
     *
     * @return array minutes => label
     */
    public static function reminder_choices() {
        return array(
            0    => __( 'No reminder', '3task-calendar' ),
            30   => __( '30 minutes before', '3task-calendar' ),
            60   => __( '1 hour before', '3task-calendar' ),
            120  => __( '2 hours before', '3task-calendar' ),
            1440 => __( '1 day before', '3task-calendar' ),
            2880 => __( '2 days before', '3task-calendar' ),
        );
    }

    /**
     * Allowed reminder values. Since 1.7.0
     *
     * @return int[]
     */
    public static function reminder_choices_minutes() {
        return array_keys( self::reminder_choices() );
    }

    /**
     * Render help tab
     */
    private function render_help() {
        ?>
        <div class="threecal-help-page">
            <!-- Quick Start -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Quick Start Guide', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'Follow these steps to display your calendar on any page or widget:', '3task-calendar' ); ?></p>
                <ol>
                    <li><?php esc_html_e( 'Create categories for your events (optional but recommended)', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Add locations where events take place (optional)', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Create your first event with title, date, and description', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Use a shortcode to display the calendar on any page, post, or widget', '3task-calendar' ); ?></li>
                </ol>
            </div>

            <!-- Main Calendar Shortcode -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Calendar Shortcode', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'Display an interactive calendar with all your events.', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Basic Usage', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal]</code>

                <h4><?php esc_html_e( 'All Parameters', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal view="month" category="1" location="2" theme="default" show_filters="true" show_legend="true" week_starts_on="1"]</code>

                <table class="widefat striped" style="margin-top: 15px;">
                    <thead>
                        <tr>
                            <th><?php esc_html_e( 'Parameter', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Default', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Description', '3task-calendar' ); ?></th>
                        </tr>
                    </thead>
                    <tbody>
                        <tr>
                            <td><code>view</code></td>
                            <td>month</td>
                            <td><?php esc_html_e( 'Calendar view: month or list', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>category</code></td>
                            <td>0</td>
                            <td><?php esc_html_e( 'Filter by category ID (0 = show all)', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>location</code></td>
                            <td>0</td>
                            <td><?php esc_html_e( 'Filter by location ID (0 = show all)', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>theme</code></td>
                            <td>default</td>
                            <td><?php esc_html_e( 'Visual theme for the calendar', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_filters</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Show category/location filter dropdowns', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_legend</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Show color legend for categories', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>week_starts_on</code></td>
                            <td><?php esc_html_e( '(from settings)', '3task-calendar' ); ?></td>
                            <td><?php esc_html_e( '0 = Sunday, 1 = Monday', '3task-calendar' ); ?></td>
                        </tr>
                    </tbody>
                </table>
            </div>

            <!-- Event List Shortcode -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Event List Shortcode', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'Display events as a list or grid.', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Basic Usage', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_events]</code>

                <h4><?php esc_html_e( 'All Parameters', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_events category="1" location="2" limit="10" view="list" show_past="false" show_pagination="true" columns="3"]</code>

                <table class="widefat striped" style="margin-top: 15px;">
                    <thead>
                        <tr>
                            <th><?php esc_html_e( 'Parameter', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Default', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Description', '3task-calendar' ); ?></th>
                        </tr>
                    </thead>
                    <tbody>
                        <tr>
                            <td><code>category</code></td>
                            <td>0</td>
                            <td><?php esc_html_e( 'Filter by category ID', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>location</code></td>
                            <td>0</td>
                            <td><?php esc_html_e( 'Filter by location ID', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>limit</code></td>
                            <td>10</td>
                            <td><?php esc_html_e( 'Number of events per page', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>view</code></td>
                            <td>list</td>
                            <td><?php esc_html_e( 'Display style: list, grid, compact or poster', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_past</code></td>
                            <td>false</td>
                            <td><?php esc_html_e( 'Include past events', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_pagination</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Show pagination controls', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>columns</code></td>
                            <td>3</td>
                            <td><?php esc_html_e( 'Number of columns in grid and poster view', '3task-calendar' ); ?></td>
                        </tr>
                    </tbody>
                </table>
            </div>

            <!-- Dates from posts -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Dates from posts', '3task-calendar' ); ?></h2>
                <p>
                    <?php esc_html_e( 'Set a date while you write a post and the post appears in the calendar. Switch it on for posts, pages or custom post types in the Posts tab, where you can also use a date field you already have.', '3task-calendar' ); ?>
                    <a href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=posts' ) ); ?>"><?php esc_html_e( 'Open the Posts tab', '3task-calendar' ); ?></a>
                </p>

                <h4><?php esc_html_e( 'Date of a post with "Add to my calendar"', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_post_date]</code>
                <p class="description"><?php esc_html_e( 'Inside a post it shows the date of that post. With id="123" it shows the date of another post, with theme="accent" another design. The block is called "Date of this post".', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Posters of the upcoming dates', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_events view="poster" category="1" columns="4"]</code>

                <h4><?php esc_html_e( 'A whole month', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_events view="poster" month="current"]</code>
                <p class="description"><?php esc_html_e( 'month takes current, next or a month such as 2026-10 and shows all dates of that month, past days included. Works with every view.', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Now showing', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_events view="poster" running="40"]</code>
                <p class="description"><?php esc_html_e( 'Lists the dates that started within the last 40 days, newest first. For example films that are in cinemas now.', '3task-calendar' ); ?></p>
            </div>

            <!-- Upcoming Events Shortcode -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Upcoming Events Shortcode', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'Perfect for sidebars and widgets. Shows a compact list of upcoming events.', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Basic Usage', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_upcoming]</code>

                <h4><?php esc_html_e( 'All Parameters', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_upcoming limit="5" category="1" show_date="true" show_time="true" show_location="true"]</code>

                <table class="widefat striped" style="margin-top: 15px;">
                    <thead>
                        <tr>
                            <th><?php esc_html_e( 'Parameter', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Default', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Description', '3task-calendar' ); ?></th>
                        </tr>
                    </thead>
                    <tbody>
                        <tr>
                            <td><code>limit</code></td>
                            <td>5</td>
                            <td><?php esc_html_e( 'Number of events to show', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>category</code></td>
                            <td>0</td>
                            <td><?php esc_html_e( 'Filter by category ID', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_date</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Display event date', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_time</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Display event time', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_location</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Display event location', '3task-calendar' ); ?></td>
                        </tr>
                    </tbody>
                </table>
            </div>

            <!-- Single Event Shortcode -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Single Event Shortcode', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'Display a specific event by its ID.', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Usage', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_event id="123" show_map="true" show_description="true"]</code>

                <table class="widefat striped" style="margin-top: 15px;">
                    <thead>
                        <tr>
                            <th><?php esc_html_e( 'Parameter', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Default', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Description', '3task-calendar' ); ?></th>
                        </tr>
                    </thead>
                    <tbody>
                        <tr>
                            <td><code>id</code></td>
                            <td><?php esc_html_e( '(required)', '3task-calendar' ); ?></td>
                            <td><?php esc_html_e( 'The event ID to display', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_map</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Show location map (requires Google Maps API key)', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_description</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Show full event description', '3task-calendar' ); ?></td>
                        </tr>
                    </tbody>
                </table>
            </div>

            <!-- Mini Calendar Shortcode -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Mini Calendar Shortcode', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'Perfect for sidebar widgets! A compact month view with event markers.', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Basic Usage', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_mini]</code>

                <h4><?php esc_html_e( 'All Parameters', '3task-calendar' ); ?></h4>
                <code class="threecal-code-block">[threecal_mini category="1" show_nav="true" show_today="true" week_starts_on="1"]</code>

                <table class="widefat striped" style="margin-top: 15px;">
                    <thead>
                        <tr>
                            <th><?php esc_html_e( 'Parameter', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Default', '3task-calendar' ); ?></th>
                            <th><?php esc_html_e( 'Description', '3task-calendar' ); ?></th>
                        </tr>
                    </thead>
                    <tbody>
                        <tr>
                            <td><code>category</code></td>
                            <td>0</td>
                            <td><?php esc_html_e( 'Filter by category ID (0 = show all)', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_nav</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Show previous/next month navigation', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>show_today</code></td>
                            <td>true</td>
                            <td><?php esc_html_e( 'Show "Today" link at the bottom', '3task-calendar' ); ?></td>
                        </tr>
                        <tr>
                            <td><code>week_starts_on</code></td>
                            <td><?php esc_html_e( '(from settings)', '3task-calendar' ); ?></td>
                            <td><?php esc_html_e( '0 = Sunday, 1 = Monday', '3task-calendar' ); ?></td>
                        </tr>
                    </tbody>
                </table>

                <div class="threecal-help-tip" style="background: #d4edda; border-left: 4px solid #28a745; padding: 12px 15px; margin-top: 15px;">
                    <strong><?php esc_html_e( 'Widget Tip:', '3task-calendar' ); ?></strong>
                    <?php esc_html_e( 'This is the ideal shortcode for sidebars! Days with events show colored dots. Click a day to see its events.', '3task-calendar' ); ?>
                </div>
            </div>

            <!-- Widget Usage -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Using in Widgets', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'All shortcodes work in widgets! Here are the best options for sidebars:', '3task-calendar' ); ?></p>

                <h4><?php esc_html_e( 'Block Editor (Recommended)', '3task-calendar' ); ?></h4>
                <ol>
                    <li><?php esc_html_e( 'Go to Appearance > Widgets', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Add a "Shortcode" block to your widget area', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Enter the shortcode, e.g.:', '3task-calendar' ); ?> <code>[threecal_upcoming limit="3"]</code></li>
                </ol>

                <h4><?php esc_html_e( 'Classic Widgets', '3task-calendar' ); ?></h4>
                <ol>
                    <li><?php esc_html_e( 'Add a "Text" widget (the "Custom HTML" widget does not run shortcodes)', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Enter the shortcode in the content area', '3task-calendar' ); ?></li>
                </ol>

                <div class="threecal-help-tip" style="background: #f0f6fc; border-left: 4px solid #3788d8; padding: 12px 15px; margin-top: 15px;">
                    <strong><?php esc_html_e( 'Best Widget Shortcodes:', '3task-calendar' ); ?></strong><br>
                    <code>[threecal_mini]</code>: <?php esc_html_e( 'Compact month view with event markers (recommended!)', '3task-calendar' ); ?><br>
                    <code>[threecal_upcoming limit="3"]</code>: <?php esc_html_e( 'Simple list of upcoming events', '3task-calendar' ); ?>
                </div>
            </div>

            <!-- Features Overview -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Features Overview', '3task-calendar' ); ?></h2>

                <div class="threecal-features-grid" style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; margin-top: 15px;">
                    <div class="feature-item">
                        <span class="dashicons dashicons-calendar-alt" style="color: #3788d8;"></span>
                        <strong><?php esc_html_e( 'Interactive Calendar', '3task-calendar' ); ?></strong>
                        <p><?php esc_html_e( 'Month and list views with navigation', '3task-calendar' ); ?></p>
                    </div>
                    <div class="feature-item">
                        <span class="dashicons dashicons-category" style="color: #3788d8;"></span>
                        <strong><?php esc_html_e( 'Categories', '3task-calendar' ); ?></strong>
                        <p><?php esc_html_e( 'Organize events with color-coded categories', '3task-calendar' ); ?></p>
                    </div>
                    <div class="feature-item">
                        <span class="dashicons dashicons-location" style="color: #3788d8;"></span>
                        <strong><?php esc_html_e( 'Locations', '3task-calendar' ); ?></strong>
                        <p><?php esc_html_e( 'Add venues with their address', '3task-calendar' ); ?></p>
                    </div>
                    <div class="feature-item">
                        <span class="dashicons dashicons-smartphone" style="color: #3788d8;"></span>
                        <strong><?php esc_html_e( 'Responsive Design', '3task-calendar' ); ?></strong>
                        <p><?php esc_html_e( 'Adapts to small screens', '3task-calendar' ); ?></p>
                    </div>
                    <div class="feature-item">
                        <span class="dashicons dashicons-filter" style="color: #3788d8;"></span>
                        <strong><?php esc_html_e( 'Filters', '3task-calendar' ); ?></strong>
                        <p><?php esc_html_e( 'Let visitors filter by category or location', '3task-calendar' ); ?></p>
                    </div>
                    <div class="feature-item">
                        <span class="dashicons dashicons-admin-appearance" style="color: #3788d8;"></span>
                        <strong><?php esc_html_e( 'Customizable', '3task-calendar' ); ?></strong>
                        <p><?php esc_html_e( 'Five themes and several display options', '3task-calendar' ); ?></p>
                    </div>
                </div>
            </div>

            <!-- Getting Category/Location IDs -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Finding Category and Location IDs', '3task-calendar' ); ?></h2>
                <p><?php esc_html_e( 'To filter events by category or location, you need their IDs:', '3task-calendar' ); ?></p>
                <ol>
                    <li><?php esc_html_e( 'Go to the Categories or Locations tab', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Click "Edit" on the item you want', '3task-calendar' ); ?></li>
                    <li><?php esc_html_e( 'Look at the URL - the number after "edit=" is the ID', '3task-calendar' ); ?></li>
                </ol>
                <p><em><?php esc_html_e( 'Example: admin.php?page=3task-calendar&tab=categories&edit=5 means the ID is 5', '3task-calendar' ); ?></em></p>
            </div>

            <!-- Support -->
            <div class="threecal-card">
                <h2><?php esc_html_e( 'Need More Help?', '3task-calendar' ); ?></h2>
                <p>
                    <?php
                    printf(
                        /* translators: %s: Support forum URL */
                        esc_html__( 'Visit our %s for questions and feature requests.', '3task-calendar' ),
                        '<a href="https://wordpress.org/support/plugin/3task-calendar/" target="_blank">' . esc_html__( 'support forum', '3task-calendar' ) . '</a>'
                    );
                    ?>
                </p>
            </div>
        </div>
        <?php
    }

    /**
     * Get event statistics
     */
    private function get_event_stats() {
        global $wpdb;

        // phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Dashboard stats, custom tables.
        $total_events     = $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}threecal_events WHERE parent_id IS NULL OR parent_id = 0" );
        $published_events = $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}threecal_events WHERE status = 'published' AND (parent_id IS NULL OR parent_id = 0)" );
        $draft_events     = $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}threecal_events WHERE status = 'draft' AND (parent_id IS NULL OR parent_id = 0)" );
        $total_categories = $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->prefix}threecal_categories" );
        // phpcs:enable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching

        return array(
            'total_events'     => $total_events ? $total_events : 0,
            'published_events' => $published_events ? $published_events : 0,
            'draft_events'     => $draft_events ? $draft_events : 0,
            'total_categories' => $total_categories ? $total_categories : 0,
        );
    }

    /**
     * Get events
     */
    private function get_events( $scope = 'all' ) {
        global $wpdb;

        $now = current_time( 'mysql' );

        // Events of which only the month is known count as upcoming until their month is over.
        $month_start = substr( $now, 0, 7 ) . '-01 00:00:00';
        $month_like  = '%"' . ThreeCal_Event::PRECISION_KEY . '":"month"%';

        // phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table for events.
        if ( 'upcoming' === $scope ) {
            $results = $wpdb->get_results(
                $wpdb->prepare(
                    "SELECT * FROM {$wpdb->prefix}threecal_events
                    WHERE (parent_id IS NULL OR parent_id = 0)
                    AND (COALESCE(end_date, start_date) >= %s OR (recurrence_rule IS NOT NULL AND recurrence_rule <> '' AND COALESCE(recurrence_end, start_date) >= %s) OR (start_date >= %s AND settings LIKE %s))
                    ORDER BY start_date ASC",
                    $now,
                    $now,
                    $month_start,
                    $month_like
                )
            );
        } elseif ( 'past' === $scope ) {
            $results = $wpdb->get_results(
                $wpdb->prepare(
                    "SELECT * FROM {$wpdb->prefix}threecal_events
                    WHERE (parent_id IS NULL OR parent_id = 0)
                    AND COALESCE(end_date, start_date) < %s
                    AND (recurrence_rule IS NULL OR recurrence_rule = '' OR COALESCE(recurrence_end, start_date) < %s)
                    AND NOT (start_date >= %s AND COALESCE(settings, '') LIKE %s)
                    ORDER BY start_date DESC",
                    $now,
                    $now,
                    $month_start,
                    $month_like
                )
            );
        } elseif ( 'submitted' === $scope ) {
            $results = $wpdb->get_results(
                $wpdb->prepare(
                    "SELECT * FROM {$wpdb->prefix}threecal_events WHERE (parent_id IS NULL OR parent_id = 0) AND status = 'draft' AND settings LIKE %s ORDER BY start_date ASC",
                    '%"' . ThreeCal_Submit::KEY . '":%'
                )
            );
        } else {
            $results = $wpdb->get_results( "SELECT * FROM {$wpdb->prefix}threecal_events WHERE parent_id IS NULL OR parent_id = 0 ORDER BY start_date ASC" );
        }
        // phpcs:enable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching

        return $results ? $results : array();
    }

    /**
     * Get categories
     */
    private function get_categories() {
        global $wpdb;

        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table for categories.
        $results = $wpdb->get_results( "
            SELECT c.*, COUNT(e.id) as event_count
            FROM {$wpdb->prefix}threecal_categories c
            LEFT JOIN {$wpdb->prefix}threecal_events e ON c.id = e.category_id
            GROUP BY c.id
            ORDER BY c.name ASC
        " );

        return $results ? $results : array();
    }

    /**
     * Get locations
     */
    private function get_locations() {
        global $wpdb;

        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table for locations.
        $results = $wpdb->get_results( "
            SELECT * FROM {$wpdb->prefix}threecal_locations
            ORDER BY name ASC
        " );

        return $results ? $results : array();
    }

    /**
     * Render mini calendar
     */
    private function render_mini_calendar() {
        $current_date = current_time('Y-m-d');
        $events = $this->get_upcoming_events(5);
        
        if ( empty( $events ) ) {
            echo '<p>' . esc_html__( 'No upcoming events.', '3task-calendar' ) . '</p>';
            return;
        }
        
        echo '<div class="threecal-mini-calendar">';
        foreach ($events as $event) {
            echo '<div class="mini-event" style="padding: 8px 0; border-bottom: 1px solid #f0f0f1;">';
            echo '<strong>' . esc_html($event->title) . '</strong><br>';
            echo '<span style="color: #6b7280; font-size: 0.9rem;">' . esc_html( wp_date( 'M j, Y', strtotime( $event->start_date ) ) ) . '</span>';
            echo '</div>';
        }
        echo '</div>';
    }

    /**
     * Get upcoming events
     */
    private function get_upcoming_events( $limit = 5 ) {
        global $wpdb;

        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table for events.
        $results = $wpdb->get_results( $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}threecal_events
            WHERE start_date >= %s AND status = 'published'
            ORDER BY start_date ASC
            LIMIT %d",
            current_time( 'Y-m-d' ),
            $limit
        ) );

        return $results ? $results : array();
    }

    /**
     * Register settings
     */
    public function register_settings() {
        register_setting('threecal_settings', 'threecal_settings', array(
            'sanitize_callback' => array($this, 'sanitize_settings')
        ));

        // Handle form submissions
        $this->handle_form_submissions();
    }

    /**
     * Sanitize settings
     */
    public function sanitize_settings($input) {
        $input  = is_array($input) ? $input : array();
        $themes = ThreeCal_Themes::all();
        $theme  = isset($input['default_theme']) ? sanitize_key($input['default_theme']) : 'default';
        $view   = isset($input['default_view']) ? sanitize_key($input['default_view']) : 'month';
        $accent = isset($input['accent_color']) ? sanitize_hex_color($input['accent_color']) : '';

        // Every key the plugin reads. A key missing here is lost on the next save.
        $sanitized = array(
            'date_format'              => sanitize_text_field($input['date_format'] ?? ''),
            'time_format'              => sanitize_text_field($input['time_format'] ?? ''),
            'week_starts_on'           => (isset($input['week_starts_on']) && 0 === absint($input['week_starts_on'])) ? 0 : 1,
            'default_view'             => in_array($view, array('month', 'list'), true) ? $view : 'month',
            'default_theme'            => isset($themes[$theme]) ? $theme : 'default',
            'accent_color'             => $accent ? $accent : '',
            'show_event_time'          => isset($input['show_event_time']) ? !empty($input['show_event_time']) : true,
            'show_event_location'      => isset($input['show_event_location']) ? !empty($input['show_event_location']) : true,
            'show_event_description'   => isset($input['show_event_description']) ? !empty($input['show_event_description']) : true,
            'events_per_page'          => max(1, absint($input['events_per_page'] ?? 10)),
            'enable_event_popup'       => isset($input['enable_event_popup']) ? !empty($input['enable_event_popup']) : true,
            'enable_schema'            => isset($input['enable_schema']) ? !empty($input['enable_schema']) : true,
            'external_links'           => (isset($input['external_links']) && 'follow' === $input['external_links']) ? 'follow' : 'nofollow',
            'ics_reminder'             => isset($input['ics_reminder']) && in_array(absint($input['ics_reminder']), self::reminder_choices_minutes(), true) ? absint($input['ics_reminder']) : 0,
            'submit_category'          => absint($input['submit_category'] ?? 0),
            'submit_notify'            => isset($input['submit_notify']) ? !empty($input['submit_notify']) : true,
            'delete_data_on_uninstall' => !empty($input['delete_data_on_uninstall']),
        );

        /**
         * Filters the sanitized settings, so extensions can keep their own keys.
         *
         * @param array $sanitized Sanitized settings.
         * @param array $input     Raw settings.
         */
        return apply_filters('threecal_sanitize_settings', $sanitized, $input);
    }

    /**
     * Handle form submissions
     */
    private function handle_form_submissions() {
        // Sample file for the CSV import.
        if ( isset( $_GET['threecal_import_sample'], $_GET['_wpnonce'] ) && wp_verify_nonce( sanitize_text_field( wp_unslash( $_GET['_wpnonce'] ) ), 'threecal_import_sample' ) ) {
            $this->send_import_sample();
        }

        // Save event.
        if ( isset( $_POST['threecal_save_event'] ) && check_admin_referer( 'threecal_save_event' ) ) {
            $this->save_event();
        }

        // Delete event.
        if ( isset( $_GET['action'] ) && 'delete' === $_GET['action'] && isset( $_GET['id'], $_GET['_wpnonce'] ) ) {
            $nonce = sanitize_text_field( wp_unslash( $_GET['_wpnonce'] ) );
            $id    = absint( $_GET['id'] );
            if ( wp_verify_nonce( $nonce, 'threecal_delete_' . $id ) ) {
                $this->delete_event( $id );
            }
        }

        // Cancel, restore or remove a single date of a series.
        if ( isset( $_GET['threecal_date_action'], $_GET['series'], $_GET['date'], $_GET['_wpnonce'] ) ) {
            $series_id = absint( $_GET['series'] );
            $nonce     = sanitize_text_field( wp_unslash( $_GET['_wpnonce'] ) );
            if ( wp_verify_nonce( $nonce, 'threecal_series_' . $series_id ) ) {
                $this->series_date_action(
                    $series_id,
                    sanitize_key( wp_unslash( $_GET['threecal_date_action'] ) ),
                    sanitize_text_field( wp_unslash( $_GET['date'] ) )
                );
            }
        }

        // Save location.
        if ( isset( $_POST['threecal_save_location'] ) && check_admin_referer( 'threecal_save_location' ) ) {
            $this->save_location();
        }

        // Delete location.
        if ( isset( $_GET['action'] ) && 'delete_location' === $_GET['action'] && isset( $_GET['id'], $_GET['_wpnonce'] ) ) {
            $nonce = sanitize_text_field( wp_unslash( $_GET['_wpnonce'] ) );
            $id    = absint( $_GET['id'] );
            if ( wp_verify_nonce( $nonce, 'threecal_delete_location_' . $id ) ) {
                $this->delete_location( $id );
            }
        }

        // Save category.
        if ( isset( $_POST['threecal_save_category'] ) && check_admin_referer( 'threecal_save_category' ) ) {
            $this->save_category();
        }

        // Delete category.
        if ( isset( $_GET['action'] ) && 'delete_category' === $_GET['action'] && isset( $_GET['id'], $_GET['_wpnonce'] ) ) {
            $nonce = sanitize_text_field( wp_unslash( $_GET['_wpnonce'] ) );
            $id    = absint( $_GET['id'] );
            if ( wp_verify_nonce( $nonce, 'threecal_delete_category_' . $id ) ) {
                $this->delete_category( $id );
            }
        }
    }

    /**
     * Save event
     */
    private function save_event() {
        if ( ! current_user_can( 'create_threecal_events' ) && ! current_user_can( 'edit_threecal_events' ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }

        // Nonce is already verified in handle_form_submissions() via check_admin_referer().
        // phpcs:disable WordPress.Security.NonceVerification.Missing -- Nonce verified in handle_form_submissions.
        $event_id = isset( $_POST['event_id'] ) ? absint( $_POST['event_id'] ) : 0;

        if ( $event_id > 0 ) {
            $event = ThreeCal_Event::get( $event_id );
            if ( ! $event ) {
                wp_die( esc_html__( 'Event not found.', '3task-calendar' ) );
            }
        } else {
            $event = new ThreeCal_Event();
        }

        // Remember where a repetition came from, so its date can be excluded from the series.
        $original_parent = (int) $event->parent_id;
        $original_day    = substr( (string) $event->start_date, 0, 10 );

        $event->title          = isset( $_POST['event_title'] ) ? sanitize_text_field( wp_unslash( $_POST['event_title'] ) ) : '';
        $event->description    = isset( $_POST['event_description'] ) ? wp_kses_post( wp_unslash( $_POST['event_description'] ) ) : '';
        $event->start_date     = isset( $_POST['event_start_date'] ) ? sanitize_text_field( wp_unslash( $_POST['event_start_date'] ) ) : '';
        $event->end_date       = isset( $_POST['event_end_date'] ) ? sanitize_text_field( wp_unslash( $_POST['event_end_date'] ) ) : '';
        $event->all_day        = isset( $_POST['event_all_day'] );
        $event->location_id    = isset( $_POST['event_location'] ) ? absint( $_POST['event_location'] ) : 0;
        $event->url            = isset( $_POST['event_url'] ) ? esc_url_raw( wp_unslash( $_POST['event_url'] ) ) : '';
        $event->featured_image = isset( $_POST['event_featured_image'] ) ? absint( $_POST['event_featured_image'] ) : 0;
        $event->color          = isset( $_POST['event_color'] ) ? ( sanitize_hex_color( wp_unslash( $_POST['event_color'] ) ) ?: '#3788d8' ) : '#3788d8';
        $event->status         = isset( $_POST['event_status'] ) ? sanitize_key( wp_unslash( $_POST['event_status'] ) ) : 'published';
        $event->set_organizer(
            isset( $_POST['event_organizer_name'] ) ? sanitize_text_field( wp_unslash( $_POST['event_organizer_name'] ) ) : '',
            isset( $_POST['event_organizer_url'] ) ? esc_url_raw( wp_unslash( $_POST['event_organizer_url'] ), array( 'http', 'https' ) ) : ''
        );

        if ( ! in_array( $event->status, array( 'draft', 'published', 'cancelled' ), true ) ) {
            $event->status = 'draft';
        }

        // Normalise dates (datetime-local sends Y-m-d\TH:i) and reject invalid input.
        $event->start_date = $this->normalize_datetime( $event->start_date );
        $event->end_date   = $event->end_date ? $this->normalize_datetime( $event->end_date ) : '';

        // Precision: the day is known, or only the month ("July 2027, date to be announced").
        $precision = ( isset( $_POST['event_date_precision'] ) && 'month' === sanitize_key( wp_unslash( $_POST['event_date_precision'] ) ) ) ? 'month' : 'day';
        if ( 'month' === $precision ) {
            $event->start_date = self::normalize_month( isset( $_POST['event_start_month'] ) ? sanitize_text_field( wp_unslash( $_POST['event_start_month'] ) ) : '' );
            if ( '' === $event->title || '' === $event->start_date ) {
                wp_die( esc_html__( 'Please enter a title and a valid month, for example 2027-07.', '3task-calendar' ), '', array( 'back_link' => true ) );
            }
            $rule = isset( $_POST['event_recurrence'] ) ? sanitize_key( wp_unslash( $_POST['event_recurrence'] ) ) : '';
            if ( '' !== $rule && ! $event->parent_id ) {
                wp_die( esc_html__( 'An event of which only the month is known cannot repeat. Set "Repeat" to "Does not repeat".', '3task-calendar' ), '', array( 'back_link' => true ) );
            }
        }

        if ( '' === $event->title || '' === $event->start_date ) {
            wp_die( esc_html__( 'Please enter a title and a valid start date.', '3task-calendar' ), '', array( 'back_link' => true ) );
        }

        $categories = isset( $_POST['event_categories'] ) ? array_map( 'absint', (array) $_POST['event_categories'] ) : array();

        /**
         * Filters whether the current user may save this event.
         *
         * @param bool           $allowed    Whether saving is allowed.
         * @param ThreeCal_Event $event      The event with the submitted values (ID 0 for a new one).
         * @param int[]          $categories Submitted category IDs.
         */
        if ( ! apply_filters( 'threecal_user_can_save_event', true, $event, $categories ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ), '', array( 'back_link' => true ) );
        }

        // An end before the start is treated as "no end".
        if ( $event->end_date && $event->end_date < $event->start_date ) {
            $event->end_date = '';
        }

        // Repeat pattern. Editing a single repetition detaches it from its series.
        if ( $event->parent_id ) {
            $event->parent_id       = 0;
            $event->recurrence_rule = '';
            $event->recurrence_end  = '';
        } else {
            $rule = isset( $_POST['event_recurrence'] ) ? sanitize_key( wp_unslash( $_POST['event_recurrence'] ) ) : '';
            $event->recurrence_rule = array_key_exists( $rule, ThreeCal_Event::recurrence_options() ) ? $rule : '';
            $until = isset( $_POST['event_recurrence_end'] ) ? $this->normalize_datetime( sanitize_text_field( wp_unslash( $_POST['event_recurrence_end'] ) ) ) : '';
            $event->recurrence_end = ( $event->recurrence_rule && $until ) ? substr( $until, 0, 10 ) . ' 23:59:59' : '';
        }

        // Month only: first of the month, all day, no end, no repeat. Day: as before.
        $event->set_date_precision( $precision );

        if ( $event->save() ) {
            // Set categories.
            $event->set_categories( $categories );
            // phpcs:enable WordPress.Security.NonceVerification.Missing

            // Create or update the repetitions of a series.
            $event->regenerate_series();

            /**
             * Fires after an event has been saved from the admin form.
             *
             * @param ThreeCal_Event $event      The saved event.
             * @param int[]          $categories Category IDs.
             */
            do_action( 'threecal_admin_event_saved', $event, $categories );

            // A detached repetition becomes an exception of its series.
            if ( $original_parent && $original_day ) {
                $parent = ThreeCal_Event::get( $original_parent );
                if ( $parent ) {
                    $exdates   = (array) $parent->get_setting( 'exdates', array() );
                    $exdates[] = $original_day;
                    $parent->set_setting( 'exdates', array_values( array_unique( $exdates ) ) );
                    $parent->save();
                }
            }

            // Redirect
            $redirect = add_query_arg(array(
                'page' => '3task-calendar',
                'tab' => 'events',
                'action' => 'edit',
                'event' => $event->id,
                'message' => 'saved'
            ), admin_url('admin.php'));

            wp_safe_redirect( $redirect );
            exit;
        } else {
            wp_die( esc_html__( 'Error saving event.', '3task-calendar' ) );
        }
    }

    /**
     * Convert a submitted date to Y-m-d H:i:s or return an empty string.
     *
     * @param string $value Submitted value.
     * @return string
     */
    private function normalize_datetime( $value ) {
        $value = trim( str_replace( 'T', ' ', (string) $value ) );
        foreach ( array( 'Y-m-d H:i:s', 'Y-m-d H:i', 'Y-m-d' ) as $format ) {
            $date = DateTime::createFromFormat( '!' . $format, $value );
            if ( $date && $date->format( $format ) === $value ) {
                return $date->format( 'Y-m-d H:i:s' );
            }
        }
        return '';
    }

    /**
     * Convert a month (YYYY-MM) to the first day of that month as Y-m-d H:i:s.
     *
     * @since 1.6.0
     * @param string $value Submitted value.
     * @return string Empty string for invalid input.
     */
    public static function normalize_month( $value ) {
        return ThreeCal_Event::parse_month( $value );
    }

    /**
     * Delete event
     */
    private function delete_event($id) {
        if (!current_user_can('delete_threecal_events')) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }

        $event = ThreeCal_Event::get($id);

        /**
         * Filters whether the current user may delete this event.
         *
         * @param bool           $allowed Whether deleting is allowed.
         * @param ThreeCal_Event $event   The event.
         */
        if ( $event && ! apply_filters( 'threecal_user_can_delete_event', true, $event ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ), '', array( 'back_link' => true ) );
        }

        if ($event && $event->delete()) {
            wp_safe_redirect( add_query_arg( array(
                'page' => '3task-calendar',
                'tab' => 'events',
                'message' => 'deleted'
            ), admin_url('admin.php')));
            exit;
        }
    }

    /**
     * Cancel, restore or remove a single date of a series.
     *
     * @param int    $series_id ID of the series (its first event).
     * @param string $action    cancel, restore or remove.
     * @param string $day       Date (Y-m-d).
     */
    private function series_date_action( $series_id, $action, $day ) {
        if ( ! current_user_can( 'edit_threecal_events' ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }

        $series = ThreeCal_Event::get( $series_id );
        if ( ! $series || $series->parent_id || ! $series->recurrence_rule || ! preg_match( '/^\d{4}-\d{2}-\d{2}$/', $day ) || ! in_array( $action, array( 'cancel', 'restore', 'remove' ), true ) ) {
            wp_die( esc_html__( 'This date could not be changed.', '3task-calendar' ), '', array( 'back_link' => true ) );
        }

        /** This filter is documented in admin/class-admin.php */
        if ( ! apply_filters( 'threecal_user_can_save_event', true, $series, wp_list_pluck( ThreeCal_Event::get_categories( $series->id ), 'id' ) ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ), '', array( 'back_link' => true ) );
        }

        $target = $series->id;
        $split  = null;
        foreach ( $series->get_split_events() as $candidate ) {
            if ( substr( (string) $candidate->start_date, 0, 10 ) === $day ) {
                $split = $candidate;
                break;
            }
        }

        if ( $split ) {
            // A former first date that is a separate event now.
            if ( 'remove' === $action ) {
                $split->delete();
                $ids = array_diff( array_map( 'absint', (array) $series->get_setting( 'split_dates', array() ) ), array( (int) $split->id ) );
                $series->set_setting( 'split_dates', array_values( $ids ) );
                $series->save();
            } else {
                $split->status = ( 'cancel' === $action && 'published' === $series->status ) ? 'cancelled' : $series->status;
                $split->save();
            }
        } elseif ( substr( (string) $series->start_date, 0, 10 ) === $day ) {
            // The first date is the series itself: the next date takes the series over.
            $next = $series->split_off_first_date();
            if ( 'remove' === $action ) {
                $series->delete();
            } elseif ( 'cancel' === $action ) {
                $series->status = 'cancelled';
                $series->save();
            }
            $target = $next ? $next : ( 'remove' === $action ? 0 : $series->id );
        } elseif ( 'remove' === $action ) {
            $series->remove_date( $day );
        } else {
            $series->set_date_cancelled( $day, 'cancel' === $action );
        }

        $args = array(
            'page'    => '3task-calendar',
            'tab'     => 'events',
            'message' => 'date_' . $action,
        );
        if ( $target ) {
            $args['action'] = 'edit';
            $args['event']  = $target;
        }

        wp_safe_redirect( add_query_arg( $args, admin_url( 'admin.php' ) ) );
        exit;
    }

    /**
     * Save location
     */
    private function save_location() {
        if ( ! current_user_can( 'manage_threecal_locations' ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }

        // Nonce is already verified in handle_form_submissions() via check_admin_referer().
        // phpcs:disable WordPress.Security.NonceVerification.Missing -- Nonce verified in handle_form_submissions.
        $location_id = isset( $_POST['location_id'] ) ? absint( $_POST['location_id'] ) : 0;

        if ( $location_id > 0 ) {
            $location = ThreeCal_Location::get( $location_id );
            if ( ! $location ) {
                wp_die( esc_html__( 'Location not found.', '3task-calendar' ) );
            }
        } else {
            $location = new ThreeCal_Location();
        }

        $location->name           = isset( $_POST['location_name'] ) ? sanitize_text_field( wp_unslash( $_POST['location_name'] ) ) : '';
        $location->address        = isset( $_POST['location_address'] ) ? sanitize_text_field( wp_unslash( $_POST['location_address'] ) ) : '';
        $location->city           = isset( $_POST['location_city'] ) ? sanitize_text_field( wp_unslash( $_POST['location_city'] ) ) : '';
        $location->postal_code    = isset( $_POST['location_postal_code'] ) ? sanitize_text_field( wp_unslash( $_POST['location_postal_code'] ) ) : '';
        $location->country        = isset( $_POST['location_country'] ) ? sanitize_text_field( wp_unslash( $_POST['location_country'] ) ) : 'DE';
        $location->phone          = isset( $_POST['location_phone'] ) ? sanitize_text_field( wp_unslash( $_POST['location_phone'] ) ) : '';
        $location->email          = isset( $_POST['location_email'] ) ? sanitize_email( wp_unslash( $_POST['location_email'] ) ) : '';
        $location->website        = isset( $_POST['location_website'] ) ? esc_url_raw( wp_unslash( $_POST['location_website'] ) ) : '';
        $location->description    = isset( $_POST['location_description'] ) ? wp_kses_post( wp_unslash( $_POST['location_description'] ) ) : '';
        $location->featured_image = isset( $_POST['location_featured_image'] ) ? absint( $_POST['location_featured_image'] ) : 0;

        $location->latitude  = ( isset( $_POST['location_latitude'] ) && '' !== trim( sanitize_text_field( wp_unslash( $_POST['location_latitude'] ) ) ) ) ? floatval( $_POST['location_latitude'] ) : null;
        $location->longitude = ( isset( $_POST['location_longitude'] ) && '' !== trim( sanitize_text_field( wp_unslash( $_POST['location_longitude'] ) ) ) ) ? floatval( $_POST['location_longitude'] ) : null;
        // phpcs:enable WordPress.Security.NonceVerification.Missing

        if ( $location->save() ) {
            wp_safe_redirect( add_query_arg( array(
                'page'    => '3task-calendar',
                'tab'     => 'locations',
                'message' => 'saved',
            ), admin_url( 'admin.php' ) ) );
            exit;
        }
    }

    /**
     * Delete location
     */
    private function delete_location($id) {
        if (!current_user_can('manage_threecal_locations')) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }

        $location = ThreeCal_Location::get($id);
        if ($location && $location->delete()) {
            wp_safe_redirect( add_query_arg( array(
                'page' => '3task-calendar',
                'tab' => 'locations',
                'message' => 'deleted'
            ), admin_url('admin.php')));
            exit;
        }
    }

    /**
     * Save category
     */
    private function save_category() {
        if ( ! current_user_can( 'manage_threecal_categories' ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }

        // Nonce is already verified in handle_form_submissions() via check_admin_referer().
        // phpcs:disable WordPress.Security.NonceVerification.Missing -- Nonce verified in handle_form_submissions.
        $category_id = isset( $_POST['category_id'] ) ? absint( $_POST['category_id'] ) : 0;

        if ( $category_id > 0 ) {
            $category = ThreeCal_Category::get( $category_id );
            if ( ! $category ) {
                wp_die( esc_html__( 'Category not found.', '3task-calendar' ) );
            }
        } else {
            $category = new ThreeCal_Category();
        }

        $category->name        = isset( $_POST['category_name'] ) ? sanitize_text_field( wp_unslash( $_POST['category_name'] ) ) : '';
        $category->slug        = isset( $_POST['category_slug'] ) ? sanitize_title( wp_unslash( $_POST['category_slug'] ) ) : '';
        $category->description = isset( $_POST['category_description'] ) ? sanitize_textarea_field( wp_unslash( $_POST['category_description'] ) ) : '';
        $category->color       = isset( $_POST['category_color'] ) ? ( sanitize_hex_color( wp_unslash( $_POST['category_color'] ) ) ?: '#3788d8' ) : '#3788d8';
        $category->parent_id   = isset( $_POST['category_parent'] ) ? absint( $_POST['category_parent'] ) : 0;
        $category->sort_order  = isset( $_POST['category_sort_order'] ) ? absint( $_POST['category_sort_order'] ) : 0;
        // phpcs:enable WordPress.Security.NonceVerification.Missing

        if ( $category->save() ) {
            // phpcs:ignore WordPress.Security.NonceVerification.Missing -- Nonce verified in handle_form_submissions.
            ThreeCal_Category::set_schema_excluded( $category->id, ! empty( $_POST['category_no_schema'] ) );
            // phpcs:ignore WordPress.Security.NonceVerification.Missing -- Nonce verified in handle_form_submissions.
            ThreeCal_Category::set_highlighted( $category->id, ! empty( $_POST['category_highlight'] ) );
            // phpcs:ignore WordPress.Security.NonceVerification.Missing -- Nonce verified in handle_form_submissions.
            ThreeCal_Category::set_follow( $category->id, ! empty( $_POST['category_follow'] ) );
            wp_safe_redirect( add_query_arg( array(
                'page'    => '3task-calendar',
                'tab'     => 'categories',
                'message' => 'saved',
            ), admin_url( 'admin.php' ) ) );
            exit;
        }
    }

    /**
     * Delete category
     */
    private function delete_category($id) {
        if (!current_user_can('manage_threecal_categories')) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }

        $category = ThreeCal_Category::get($id);
        if ($category && $category->delete()) {
            ThreeCal_Category::set_schema_excluded($id, false);
            wp_safe_redirect( add_query_arg( array(
                'page' => '3task-calendar',
                'tab' => 'categories',
                'message' => 'deleted'
            ), admin_url('admin.php')));
            exit;
        }
    }

    /**
     * Transient that holds a checked import between preview and import.
     *
     * @since 1.6.0
     * @param int    $user_id User ID.
     * @param string $token   Random token of the preview.
     * @return string
     */
    private static function import_transient( $user_id, $token ) {
        return 'threecal_import_' . (int) $user_id . '_' . $token;
    }

    /**
     * Importer with the rights of the current user: categories and locations
     * are only created by users who may manage them.
     *
     * @since 1.6.0
     * @return ThreeCal_Importer
     */
    private function importer() {
        return new ThreeCal_Importer(
            array(
                'create_categories' => current_user_can( 'manage_threecal_categories' ),
                'create_locations'  => current_user_can( 'manage_threecal_locations' ),
            )
        );
    }

    /**
     * Check the uploaded CSV file.
     *
     * @since 1.6.0
     * @return array|WP_Error Array( temporary path, file name ).
     */
    private function uploaded_csv() {
        // phpcs:disable WordPress.Security.NonceVerification.Missing -- Nonce checked in render_import() before this is called.
        if ( empty( $_FILES['threecal_csv'] ) || ! is_array( $_FILES['threecal_csv'] ) ) {
            return new WP_Error( 'threecal_import_nofile', __( 'Please choose a CSV file.', '3task-calendar' ) );
        }
        $error = isset( $_FILES['threecal_csv']['error'] ) ? (int) $_FILES['threecal_csv']['error'] : UPLOAD_ERR_NO_FILE;
        $size  = isset( $_FILES['threecal_csv']['size'] ) ? (int) $_FILES['threecal_csv']['size'] : 0;
        // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- Temporary path from PHP, checked with is_uploaded_file() below.
        $tmp   = isset( $_FILES['threecal_csv']['tmp_name'] ) ? (string) $_FILES['threecal_csv']['tmp_name'] : '';
        $name  = isset( $_FILES['threecal_csv']['name'] ) ? sanitize_file_name( wp_unslash( $_FILES['threecal_csv']['name'] ) ) : '';
        // phpcs:enable WordPress.Security.NonceVerification.Missing

        if ( UPLOAD_ERR_NO_FILE === $error ) {
            return new WP_Error( 'threecal_import_nofile', __( 'Please choose a CSV file.', '3task-calendar' ) );
        }
        if ( UPLOAD_ERR_INI_SIZE === $error || UPLOAD_ERR_FORM_SIZE === $error || $size > ThreeCal_Importer::MAX_BYTES ) {
            /* translators: %s: maximum file size, for example "2 MB" */
            return new WP_Error( 'threecal_import_size', sprintf( __( 'The file is larger than %s.', '3task-calendar' ), size_format( ThreeCal_Importer::MAX_BYTES ) ) );
        }
        if ( UPLOAD_ERR_OK !== $error || '' === $tmp || ! is_uploaded_file( $tmp ) ) {
            return new WP_Error( 'threecal_import_upload', __( 'The upload did not work. Please try again.', '3task-calendar' ) );
        }
        if ( ! in_array( strtolower( pathinfo( $name, PATHINFO_EXTENSION ) ), array( 'csv', 'txt' ), true ) ) {
            return new WP_Error( 'threecal_import_type', __( 'Please upload a file ending in .csv.', '3task-calendar' ) );
        }

        return array( $tmp, $name );
    }

    /**
     * Send the sample CSV for the import.
     *
     * @since 1.6.0
     */
    private function send_import_sample() {
        if ( ! current_user_can( 'edit_threecal_events' ) ) {
            wp_die( esc_html__( 'Permission denied.', '3task-calendar' ) );
        }
        nocache_headers();
        header( 'Content-Type: text/csv; charset=utf-8' );
        header( 'Content-Disposition: attachment; filename="3task-calendar-import-sample.csv"' );
        echo ThreeCal_Importer::sample_csv(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- CSV download, not HTML.
        exit;
    }

    /**
     * Render import tab: upload a CSV file, check the preview, then import.
     *
     * @since 1.6.0
     */
    private function render_import() {
        if ( ! current_user_can( 'edit_threecal_events' ) ) {
            echo '<div class="notice notice-error"><p>' . esc_html__( 'Permission denied.', '3task-calendar' ) . '</p></div>';
            return;
        }

        $user_id = get_current_user_id();
        $plan    = null;
        $result  = null;
        $token   = '';
        $error   = '';
        $file    = '';

        if ( isset( $_POST['threecal_import_preview'] ) ) {
            check_admin_referer( 'threecal_import_upload' );
            $status = ( isset( $_POST['threecal_import_status'] ) && 'publish' === sanitize_key( wp_unslash( $_POST['threecal_import_status'] ) ) ) ? 'publish' : 'draft';
            $upload = $this->uploaded_csv();
            $parsed = is_wp_error( $upload ) ? $upload : ThreeCal_Importer::read_file( $upload[0] );
            if ( is_wp_error( $parsed ) ) {
                $error = $parsed->get_error_message();
            } else {
                $file  = $upload[1];
                $plan  = $this->importer()->analyze( $parsed, $status );
                $token = wp_generate_password( 24, false );
                // Only the checked plan is kept, on the server and for this user.
                set_transient(
                    self::import_transient( $user_id, $token ),
                    array(
                        'user' => $user_id,
                        'file' => $file,
                        'plan' => $plan,
                    ),
                    30 * MINUTE_IN_SECONDS
                );
            }
        } elseif ( isset( $_POST['threecal_import_run'] ) ) {
            $token = isset( $_POST['threecal_import_token'] ) ? preg_replace( '/[^A-Za-z0-9]/', '', sanitize_text_field( wp_unslash( $_POST['threecal_import_token'] ) ) ) : '';
            check_admin_referer( 'threecal_import_run_' . $token );
            $stored = '' !== $token ? get_transient( self::import_transient( $user_id, $token ) ) : false;
            if ( ! is_array( $stored ) || (int) $stored['user'] !== $user_id || empty( $stored['plan'] ) ) {
                $error = __( 'The preview has expired. Please upload the file again.', '3task-calendar' );
            } else {
                delete_transient( self::import_transient( $user_id, $token ) );
                $plan   = $stored['plan'];
                $file   = $stored['file'];
                $result = $this->importer()->run( $plan );
            }
        }

        $labels     = array(
            'new'    => __( 'New', '3task-calendar' ),
            'update' => __( 'Will be updated', '3task-calendar' ),
            'error'  => __( 'Error', '3task-calendar' ),
        );
        $sample_url = wp_nonce_url( admin_url( 'admin.php?page=3task-calendar&tab=import&threecal_import_sample=1' ), 'threecal_import_sample' );
        $base_url   = admin_url( 'admin.php?page=3task-calendar&tab=import' );
        ?>
        <?php if ( '' !== $error ) : ?>
        <div class="notice notice-error"><p><?php echo esc_html( $error ); ?></p></div>
        <?php endif; ?>

        <?php if ( $result ) : ?>
        <div class="notice notice-success">
            <p>
                <?php
                echo esc_html(
                    sprintf(
                        /* translators: 1: created events, 2: updated events, 3: rows with errors */
                        __( 'Import done: %1$s new, %2$s updated, %3$s rows with errors skipped.', '3task-calendar' ),
                        number_format_i18n( $result['created'] ),
                        number_format_i18n( $result['updated'] ),
                        number_format_i18n( $result['skipped'] + $result['failed'] )
                    )
                );
                ?>
                <?php if ( $result['categories_created'] || $result['locations_created'] ) : ?>
                <br>
                <?php
                echo esc_html(
                    sprintf(
                        /* translators: 1: number of categories, 2: number of locations */
                        __( 'Created along the way: %1$s categories, %2$s locations.', '3task-calendar' ),
                        number_format_i18n( $result['categories_created'] ),
                        number_format_i18n( $result['locations_created'] )
                    )
                );
                ?>
                <?php endif; ?>
            </p>
            <?php foreach ( $result['messages'] as $message ) : ?>
            <p><?php echo esc_html( $message ); ?></p>
            <?php endforeach; ?>
            <p>
                <a class="button button-primary" href="<?php echo esc_url( admin_url( 'admin.php?page=3task-calendar&tab=events&scope=all' ) ); ?>"><?php esc_html_e( 'Show events', '3task-calendar' ); ?></a>
                <a class="button" href="<?php echo esc_url( $base_url ); ?>"><?php esc_html_e( 'Import another file', '3task-calendar' ); ?></a>
            </p>
        </div>
        <?php elseif ( $plan ) : ?>
        <div class="threecal-card threecal-import-preview">
            <h3><?php esc_html_e( 'Preview', '3task-calendar' ); ?> <span class="threecal-muted"><?php echo esc_html( $file ); ?></span></h3>
            <p>
                <?php
                echo esc_html(
                    sprintf(
                        /* translators: 1: new events, 2: updated events, 3: rows with errors */
                        __( 'Nothing has been saved yet. %1$s new, %2$s will be updated, %3$s rows with errors.', '3task-calendar' ),
                        number_format_i18n( $plan['counts']['new'] ),
                        number_format_i18n( $plan['counts']['update'] ),
                        number_format_i18n( $plan['counts']['error'] )
                    )
                );
                ?>
            </p>
            <?php if ( ! empty( $plan['unknown'] ) ) : ?>
            <p class="description">
                <?php
                /* translators: %s: list of column names */
                echo esc_html( sprintf( __( 'Unknown columns are ignored: %s', '3task-calendar' ), implode( ', ', $plan['unknown'] ) ) );
                ?>
            </p>
            <?php endif; ?>
            <?php if ( ! empty( $plan['new_categories'] ) ) : ?>
            <p class="description">
                <?php
                /* translators: %s: list of names */
                echo esc_html( sprintf( __( 'New categories: %s', '3task-calendar' ), implode( ', ', $plan['new_categories'] ) ) );
                ?>
            </p>
            <?php endif; ?>
            <?php if ( ! empty( $plan['new_locations'] ) ) : ?>
            <p class="description">
                <?php
                /* translators: %s: list of names */
                echo esc_html( sprintf( __( 'New locations: %s', '3task-calendar' ), implode( ', ', $plan['new_locations'] ) ) );
                ?>
            </p>
            <?php endif; ?>

            <div class="threecal-import-table-wrap">
            <table class="widefat striped threecal-import-table">
                <thead>
                    <tr>
                        <th scope="col"><?php esc_html_e( 'Row', '3task-calendar' ); ?></th>
                        <th scope="col"><?php esc_html_e( 'Result', '3task-calendar' ); ?></th>
                        <th scope="col"><?php esc_html_e( 'Title', '3task-calendar' ); ?></th>
                        <th scope="col"><?php esc_html_e( 'Date', '3task-calendar' ); ?></th>
                        <th scope="col"><?php esc_html_e( 'Note', '3task-calendar' ); ?></th>
                    </tr>
                </thead>
                <tbody>
                    <?php foreach ( $plan['rows'] as $item ) : ?>
                    <tr class="is-<?php echo esc_attr( $item['action'] ); ?>">
                        <td><?php echo esc_html( $item['row'] ); ?></td>
                        <td><span class="threecal-import-badge is-<?php echo esc_attr( $item['action'] ); ?>"><?php echo esc_html( $labels[ $item['action'] ] ); ?></span></td>
                        <td><?php echo esc_html( $item['title'] ); ?></td>
                        <td>
                            <?php
                            if ( ! empty( $item['data'] ) ) {
                                $threecal_ts = strtotime( $item['data']['start'] );
                                if ( 'month' === $item['data']['precision'] ) {
                                    echo esc_html( date_i18n( 'F Y', $threecal_ts ) . ' · ' . ThreeCal_Event::tba_text() );
                                } else {
                                    echo esc_html( date_i18n( threecal_date_format(), $threecal_ts ) . ( $item['data']['all_day'] ? '' : ' · ' . date_i18n( threecal_time_format(), $threecal_ts ) ) );
                                }
                            }
                            ?>
                        </td>
                        <td><?php echo esc_html( $item['message'] ); ?></td>
                    </tr>
                    <?php endforeach; ?>
                </tbody>
            </table>
            </div>

            <form method="post" class="threecal-import-run">
                <?php wp_nonce_field( 'threecal_import_run_' . $token ); ?>
                <input type="hidden" name="threecal_import_token" value="<?php echo esc_attr( $token ); ?>">
                <p>
                    <button type="submit" name="threecal_import_run" class="button button-primary"<?php disabled( 0 === $plan['counts']['new'] + $plan['counts']['update'] ); ?>><?php esc_html_e( 'Run import', '3task-calendar' ); ?></button>
                    <a class="button" href="<?php echo esc_url( $base_url ); ?>"><?php esc_html_e( 'Cancel', '3task-calendar' ); ?></a>
                </p>
                <p class="description"><?php esc_html_e( 'Rows with errors are skipped. The preview stays valid for 30 minutes.', '3task-calendar' ); ?></p>
            </form>
        </div>
        <?php else : ?>
        <div class="threecal-card">
            <h3><?php esc_html_e( 'Import events from a CSV file', '3task-calendar' ); ?></h3>
            <p><?php esc_html_e( 'Upload a CSV file. You first see a preview of what will happen, nothing is saved before you confirm. A row with an import_key that already exists updates that event, so the same file can be imported again without creating duplicates.', '3task-calendar' ); ?></p>
            <form method="post" enctype="multipart/form-data" class="threecal-import-form">
                <?php wp_nonce_field( 'threecal_import_upload' ); ?>
                <table class="form-table" role="presentation">
                    <tr>
                        <th scope="row"><label for="threecal_csv"><?php esc_html_e( 'CSV file', '3task-calendar' ); ?></label></th>
                        <td>
                            <input type="file" id="threecal_csv" name="threecal_csv" accept=".csv,text/csv" required>
                            <p class="description">
                                <?php
                                /* translators: %s: maximum file size, for example "2 MB" */
                                echo esc_html( sprintf( __( 'UTF-8, separator ; or , (found automatically), at most %s.', '3task-calendar' ), size_format( ThreeCal_Importer::MAX_BYTES ) ) );
                                ?>
                            </p>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><label for="threecal_import_status"><?php esc_html_e( 'Status of new events', '3task-calendar' ); ?></label></th>
                        <td>
                            <select id="threecal_import_status" name="threecal_import_status">
                                <option value="draft" selected><?php esc_html_e( 'Draft', '3task-calendar' ); ?></option>
                                <option value="publish"><?php esc_html_e( 'Published', '3task-calendar' ); ?></option>
                            </select>
                            <p class="description"><?php esc_html_e( 'A status column in the file wins. Updated events keep their status unless the file sets one.', '3task-calendar' ); ?></p>
                        </td>
                    </tr>
                </table>
                <p>
                    <button type="submit" name="threecal_import_preview" class="button button-primary"><?php esc_html_e( 'Show preview', '3task-calendar' ); ?></button>
                    <a class="button" href="<?php echo esc_url( $sample_url ); ?>"><?php ThreeCal_Icons::render( 'download', 16 ); ?> <?php esc_html_e( 'Download sample file', '3task-calendar' ); ?></a>
                </p>
            </form>
        </div>

        <div class="threecal-card">
            <h3><?php esc_html_e( 'Columns', '3task-calendar' ); ?></h3>
            <p><?php esc_html_e( 'The first line holds the column names, upper or lower case does not matter. Only title and start are required.', '3task-calendar' ); ?></p>
            <table class="widefat striped">
                <tbody>
                    <tr><td><code>import_key</code></td><td><?php esc_html_e( 'Your own unique key, for example festival-2027-summer. Importing a row with the same key again updates the event.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>title</code> *</td><td><?php esc_html_e( 'Title of the event.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>start</code> *</td><td><?php esc_html_e( 'YYYY-MM-DD, YYYY-MM-DD HH:MM, or YYYY-MM when only the month is known. Visitors then see the month and "Date to be announced".', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>end</code></td><td><?php esc_html_e( 'YYYY-MM-DD or YYYY-MM-DD HH:MM. Stays empty when only the month is known.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>all_day</code></td><td><?php esc_html_e( '1 or 0. Empty: all day when start has no time.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>url</code></td><td><?php esc_html_e( 'Link to more information (http or https).', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>description</code></td><td><?php esc_html_e( 'Text of the event, simple HTML is allowed.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>category</code></td><td><?php esc_html_e( 'Name of the category, several separated by |. Missing categories are created.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>location_name</code>, <code>address</code>, <code>postal_code</code>, <code>city</code>, <code>country</code></td><td><?php esc_html_e( 'Location. A location with the same name and city is used again, otherwise a new one is created. country is a two-letter code such as DE.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>status</code></td><td><?php esc_html_e( 'draft, publish or cancelled. Overrides the status chosen above.', '3task-calendar' ); ?></td></tr>
                    <tr><td><code>organizer_name</code>, <code>organizer_url</code></td><td><?php esc_html_e( 'Who runs the event and their website (http or https). Search engines show it as the organizer. Leave empty if you only list the event.', '3task-calendar' ); ?></td></tr>
                </tbody>
            </table>
            <p class="description"><?php esc_html_e( 'When an event is updated, columns that are missing in the file keep their values. With WP-CLI: wp threecal import file.csv --dry-run', '3task-calendar' ); ?></p>
        </div>
        <?php endif; ?>
        <?php
    }

    /**
     * Render edit event form (inline in events tab)
     */
    private function render_edit_event() {
        include THREECAL_PLUGIN_DIR . 'admin/views/event-edit.php';
    }

    /**
     * Render new event form (inline in events tab)
     */
    private function render_new_event() {
        include THREECAL_PLUGIN_DIR . 'admin/views/event-edit.php';
    }

}