<?php
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Backend class for WANotifier plugin v3
 *
 * Consolidates admin menu registration, settings management, REST API endpoints,
 * and the React shell view. Replaces the former Dashboard, Settings, Tools, and
 * WooCommerce Configure classes.
 *
 * @package Notifier
 */
class Notifier_Backend {

    // ========================================
    // 1. INITIALIZATION
    // ========================================

    public static function init() {
        add_action( 'admin_menu', array( __CLASS__, 'register_menus' ) );
        add_action( 'admin_menu', array( __CLASS__, 'manage_menu_visibility' ), 999 );
        add_action( 'admin_init', array( __CLASS__, 'handle_disconnect_action' ) );
        add_action( 'rest_api_init', array( __CLASS__, 'register_rest_routes' ) );
        add_filter( 'plugin_action_links_notifier/notifier.php', array( __CLASS__, 'add_plugin_action_links' ) );
    }

    public static function add_plugin_action_links( $links ) {
        $settings_link = '<a href="' . esc_url( admin_url( 'admin.php?page=notifier' ) ) . '">' . __( 'Settings', 'notifier' ) . '</a>';
        array_unshift( $links, $settings_link );
        return $links;
    }

    // ========================================
    // 2. MENU REGISTRATION
    // ========================================

    public static function register_menus() {
        add_menu_page(
            'WANotifier',
            'WANotifier',
            'manage_options',
            NOTIFIER_NAME,
            array( __CLASS__, 'render_react_app' ),
            'data:image/svg+xml;base64,' . base64_encode( file_get_contents( NOTIFIER_PATH . 'assets/images/menu-icon.svg' ) ),
            '51'
        );

        add_submenu_page(
            NOTIFIER_NAME,
            __( 'Integrations', 'notifier' ),
            __( 'Integrations', 'notifier' ),
            'manage_options',
            NOTIFIER_NAME,
            array( __CLASS__, 'render_react_app' )
        );

        add_submenu_page(
            NOTIFIER_NAME,
            __( 'WhatsApp Chat Button', 'notifier' ),
            __( 'Chat Button', 'notifier' ),
            'manage_options',
            'notifier-chat-button',
            array( __CLASS__, 'render_react_app' )
        );

        add_submenu_page(
            NOTIFIER_NAME,
            __( 'Settings', 'notifier' ),
            __( 'Settings', 'notifier' ),
            'manage_options',
            'notifier-settings',
            array( __CLASS__, 'render_react_app' )
        );

        add_submenu_page(
            NOTIFIER_NAME,
            __( 'Logs', 'notifier' ),
            __( 'Logs', 'notifier' ),
            'manage_options',
            'notifier-logs',
            array( __CLASS__, 'render_react_app' )
        );

        add_submenu_page(
            NOTIFIER_NAME,
            __( 'Migrate to v3', 'notifier' ),
            __( 'Migrate to v3', 'notifier' ),
            'manage_options',
            'notifier-migration',
            array( __CLASS__, 'render_react_app' )
        );
    }

    /**
     * Manage submenu visibility based on application state.
     */
    public static function manage_menu_visibility() {
        global $submenu;

        if ( empty( $submenu[ NOTIFIER_NAME ] ) ) {
            return;
        }

        $migration_complete = Notifier_Migration::is_migration_complete();
        $has_legacy         = Notifier_Migration::has_legacy_triggers();

        if ( ! $migration_complete && $has_legacy ) {
            // Migration pending: show only "Migrate to v3".
            foreach ( $submenu[ NOTIFIER_NAME ] as $key => $item ) {
                if ( isset( $item[2] ) && 'notifier-migration' !== $item[2] ) {
                    unset( $submenu[ NOTIFIER_NAME ][ $key ] );
                }
            }
        } else {
            // Migration complete or no legacy triggers: hide migration page.
            foreach ( $submenu[ NOTIFIER_NAME ] as $key => $item ) {
                if ( isset( $item[2] ) && 'notifier-migration' === $item[2] ) {
                    unset( $submenu[ NOTIFIER_NAME ][ $key ] );
                }
            }
        }

        // Always hide legacy trigger CPT menu items.
        foreach ( $submenu[ NOTIFIER_NAME ] as $key => $item ) {
            if ( isset( $item[2] ) && (
                'edit.php?post_type=wa_notifier_trigger' === $item[2] ||
                'post-new.php?post_type=wa_notifier_trigger' === $item[2]
            ) ) {
                unset( $submenu[ NOTIFIER_NAME ][ $key ] );
            }
        }
    }

    // ========================================
    // 3. REACT SHELL VIEW
    // ========================================

    public static function render_react_app() {
        include_once NOTIFIER_PATH . 'views/admin.php';
    }

    // ========================================
    // 4. DISCONNECT HANDLER
    // ========================================

    public static function handle_disconnect_action() {
        if ( ! isset( $_GET['notifier_disconnect'] ) || ! isset( $_GET['notifier_slug'] ) ) {
            return;
        }

        if ( empty( $_GET['_wpnonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_GET['_wpnonce'] ) ), 'notifier_disconnect_' . sanitize_key( $_GET['notifier_slug'] ) ) ) {
            return;
        }

        if ( ! current_user_can( 'manage_options' ) ) {
            return;
        }

        $slug = sanitize_key( $_GET['notifier_slug'] );
        Notifier_Connection::disconnect( $slug );

        wp_safe_redirect( admin_url( 'admin.php?page=notifier&disconnected=' . $slug ) );
        exit;
    }

    // ========================================
    // 5. REST API ROUTES
    // ========================================

    public static function register_rest_routes() {
        $namespace = 'notifier/v1';

        register_rest_route( $namespace, '/admin/integrations', array(
            'methods'             => 'GET',
            'callback'            => array( __CLASS__, 'rest_get_integrations' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );

        register_rest_route( $namespace, '/admin/settings', array(
            array(
                'methods'             => 'GET',
                'callback'            => array( __CLASS__, 'rest_get_settings' ),
                'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
            ),
            array(
                'methods'             => 'POST',
                'callback'            => array( __CLASS__, 'rest_save_settings' ),
                'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
            ),
        ) );

        register_rest_route( $namespace, '/admin/search-content', array(
            'methods'             => 'GET',
            'callback'            => array( __CLASS__, 'rest_search_content' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );
        register_rest_route( $namespace, '/admin/sync-triggers', array(
            'methods'             => 'POST',
            'callback'            => array( __CLASS__, 'rest_sync_triggers' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );

        register_rest_route( $namespace, '/admin/preview-btn-style', array(
            'methods'             => 'POST',
            'callback'            => array( __CLASS__, 'rest_preview_btn_style' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );

        register_rest_route( $namespace, '/admin/logs/dates', array(
            'methods'             => 'GET',
            'callback'            => array( __CLASS__, 'rest_get_log_dates' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );

        register_rest_route( $namespace, '/admin/logs', array(
            array(
                'methods'             => 'GET',
                'callback'            => array( __CLASS__, 'rest_get_logs' ),
                'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
            ),
            array(
                'methods'             => 'DELETE',
                'callback'            => array( __CLASS__, 'rest_delete_logs' ),
                'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
            ),
        ) );

        register_rest_route( $namespace, '/admin/migration-status', array(
            'methods'             => 'GET',
            'callback'            => array( __CLASS__, 'rest_get_migration_status' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );

        register_rest_route( $namespace, '/admin/finalize-migration', array(
            'methods'             => 'POST',
            'callback'            => array( __CLASS__, 'rest_finalize_migration' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );

        register_rest_route( $namespace, '/admin/disconnect', array(
            'methods'             => 'POST',
            'callback'            => array( __CLASS__, 'rest_disconnect' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );

        register_rest_route( $namespace, '/admin/wp-available-meta-fields', array(
            'methods'             => 'GET',
            'callback'            => array( __CLASS__, 'rest_get_wp_available_meta_fields' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );
        register_rest_route( $namespace, '/admin/sync-meta-fields', array(
            'methods'             => 'POST',
            'callback'            => array( __CLASS__, 'rest_sync_meta_fields' ),
            'permission_callback' => array( __CLASS__, 'rest_permission_check' ),
        ) );
    }

    public static function rest_permission_check() {
        return current_user_can( 'manage_options' );
    }

    // ========================================
    // 6. REST HANDLERS — INTEGRATIONS
    // ========================================

    public static function rest_get_integrations() {
        $integrations = self::get_integrations();
        $result       = array();

        foreach ( $integrations as $slug => $integration ) {
            $no_connect   = ! empty( $integration['no_connect'] );
            $is_connected = ! $no_connect && Notifier_Connection::is_connected( $slug );
            $connect_url  = ! $no_connect ? Notifier_Connection::get_connect_url( $slug ) : '';

            $disconnect_url = wp_nonce_url(
                admin_url( 'admin.php?page=notifier&notifier_disconnect=1&notifier_slug=' . $slug ),
                'notifier_disconnect_' . $slug
            );

            $conn          = $is_connected ? Notifier_Connection::get_connection_info( $slug ) : array();
            $connected_at  = ! empty( $conn['connected_at'] ) ? $conn['connected_at'] : '';

            $result[ $slug ] = array_merge( $integration, array(
                'slug'            => $slug,
                'is_connected'    => $is_connected,
                'connect_url'     => $connect_url,
                'disconnect_url'  => $disconnect_url,
                'connected_at'    => $connected_at,
            ) );
        }

        $result['_meta'] = array(
            'has_woo_legacy_triggers' => ! Notifier_Migration::is_migration_complete() && in_array( Notifier_Migration::get_trigger_scenario(), array( 'woo_only', 'mixed' ), true ),
            'is_woo_active'           => class_exists( 'WooCommerce' ),
            'is_wanowc_active' => Notifier::is_woo_handled_by_standalone_plugin(),
        );

        return new WP_REST_Response( $result, 200 );
    }

    // ========================================
    // 7. REST HANDLERS — SETTINGS
    // ========================================

    public static function rest_get_settings() {
        return new WP_REST_Response( self::get_all_settings(), 200 );
    }

    public static function rest_save_settings( WP_REST_Request $request ) {
        $data    = $request->get_json_params();
        $errors  = array();
        $allowed = self::get_settings_field_definitions();

        // The chat button can't be enabled without a WhatsApp number (it would silently not render).
        $enabling_ctc = isset( $data['ctc_enable'] ) && ( 'yes' === $data['ctc_enable'] || '1' === $data['ctc_enable'] || true === $data['ctc_enable'] );
        $ctc_number   = isset( $data['ctc_whatsapp_number'] ) ? trim( (string) $data['ctc_whatsapp_number'] ) : get_option( 'notifier_ctc_whatsapp_number', '' );
        if ( $enabling_ctc && '' === $ctc_number ) {
            return new WP_REST_Response( array(
                'success' => false,
                'errors'  => array( __( 'Please enter a WhatsApp number to enable the chat button.', 'notifier' ) ),
            ), 200 );
        }

        foreach ( $data as $key => $value ) {
            if ( ! isset( $allowed[ $key ] ) ) {
                continue;
            }

            $def         = $allowed[ $key ];
            $option_name = NOTIFIER_PREFIX . $key;

            switch ( $def['type'] ) {
                case 'checkbox':
                    $value = ( 'yes' === $value || '1' === $value || true === $value ) ? 'yes' : 'no';
                    break;
                case 'number':
                    $value = absint( $value );
                    if ( isset( $def['min'] ) ) {
                        $value = max( $def['min'], $value );
                    }
                    break;
                case 'select':
                    if ( ! empty( $def['options'] ) && ! array_key_exists( $value, $def['options'] ) ) {
                        $value = $def['default'] ?? '';
                    }
                    break;
                case 'textarea':
                    $value = wp_kses_post( trim( $value ) );
                    break;
                case 'display_rules':
                    $value = self::sanitize_ctc_display_rules( is_array( $value ) ? $value : array() );
                    break;
                case 'array':
                    $value = is_array( $value ) ? array_map( 'sanitize_text_field', $value ) : array();
                    if ( ! empty( $def['options'] ) ) {
                        $value = array_values( array_intersect( $value, array_keys( $def['options'] ) ) );
                    }
                    break;
                default:
                    $value = sanitize_text_field( $value );
                    break;
            }

            if ( 'ctc_whatsapp_number' === $key && ! empty( $value ) && function_exists( 'notifier_validate_phone_number' ) && ! notifier_validate_phone_number( $value ) ) {
                $errors[] = __( 'Please enter a valid WhatsApp phone number with country code.', 'notifier' );
                continue;
            }

            update_option( $option_name, $value, 'yes' );
        }

        if ( ! empty( $errors ) ) {
            return new WP_REST_Response( array(
                'success' => false,
                'errors'  => $errors,
            ), 200 );
        }

        return new WP_REST_Response( array(
            'success'  => true,
            'message'  => __( 'Settings saved.', 'notifier' ),
            'settings' => self::get_all_settings(),
        ), 200 );
    }

    // ========================================
    // 8. REST HANDLERS — SYNC TRIGGERS
    // ========================================

    public static function rest_sync_triggers( WP_REST_Request $request ) {
        $slug = sanitize_key( $request->get_param( 'slug' ) );

        if ( empty( $slug ) || ! Notifier_Connection::is_connected( $slug ) ) {
            return new WP_REST_Response( array(
                'success' => false,
                'message' => __( 'Integration not connected.', 'notifier' ),
            ), 400 );
        }

        $trigger_schema = Notifier_Connection::build_trigger_schema( $slug );
        $result = Notifier_Connection::send_saas_request( $slug, 'sync', array( 'triggers' => $trigger_schema ) );

        return new WP_REST_Response( array(
            'success' => ( false !== $result ),
            'message' => ( false !== $result ) ? __( 'Triggers synced successfully.', 'notifier' ) : __( 'Failed to sync with SaaS.', 'notifier' ),
        ), 200 );
    }

    public static function rest_disconnect( WP_REST_Request $request ) {
        $data = $request->get_json_params();
        $slug = isset( $data['slug'] ) ? sanitize_key( $data['slug'] ) : '';

        if ( empty( $slug ) ) {
            return new WP_REST_Response( array( 'success' => false, 'message' => __( 'Invalid slug.', 'notifier' ) ), 400 );
        }

        Notifier_Connection::disconnect( $slug );

        return new WP_REST_Response( array( 'success' => true, 'message' => __( 'Disconnected successfully.', 'notifier' ) ), 200 );
    }

    // ========================================
    // 9. REST HANDLERS — CHAT BUTTON PREVIEW
    // ========================================

    public static function rest_preview_btn_style( WP_REST_Request $request ) {
        $btn_style    = sanitize_text_field( $request->get_param( 'btn_style' ) );
        $valid_styles = array_keys( self::get_button_styles() );

        if ( ! in_array( $btn_style, $valid_styles, true ) || 'default' === $btn_style ) {
            return new WP_REST_Response( array( 'preview' => '' ), 200 );
        }

        $template = NOTIFIER_PATH . 'templates/buttons/' . $btn_style . '.php';
        if ( ! file_exists( $template ) ) {
            return new WP_REST_Response( array( 'preview' => '' ), 200 );
        }

        ob_start();
        include $template;
        $html = ob_get_clean();

        return new WP_REST_Response( array( 'preview' => $html ), 200 );
    }

    // ========================================
    // 10. REST HANDLERS — LOGS
    // ========================================

    public static function rest_get_log_dates() {
        global $wpdb;
        $table_name = $wpdb->prefix . NOTIFIER_ACTIVITY_TABLE_NAME;

        $dates = $wpdb->get_col( "SELECT DISTINCT DATE(timestamp) as log_date FROM `$table_name` ORDER BY log_date DESC" );

        $formatted = array();
        foreach ( $dates as $date ) {
            $formatted[] = function_exists( 'notifier_convert_date_from_utc' )
                ? notifier_convert_date_from_utc( $date, 'Y-m-d' )
                : $date;
        }

        return new WP_REST_Response( $formatted, 200 );
    }

    public static function rest_get_logs( WP_REST_Request $request ) {
        $date = sanitize_text_field( $request->get_param( 'date' ) );

        if ( empty( $date ) ) {
            return new WP_REST_Response( array(), 200 );
        }

        global $wpdb;
        $table_name = $wpdb->prefix . NOTIFIER_ACTIVITY_TABLE_NAME;

        $logs = $wpdb->get_results( $wpdb->prepare(
            "SELECT log_id, timestamp, message, type FROM `$table_name` WHERE DATE(timestamp) = %s ORDER BY timestamp DESC",
            $date
        ) );

        return new WP_REST_Response( $logs ?: array(), 200 );
    }

    public static function rest_delete_logs() {
        global $wpdb;
        $table_name = $wpdb->prefix . NOTIFIER_ACTIVITY_TABLE_NAME;

        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Custom table; $table_name from trusted constant and $wpdb->prefix only.
        $wpdb->query( "TRUNCATE TABLE `{$table_name}`" );

        return new WP_REST_Response( array(
            'success' => true,
            'message' => __( 'All logs have been deleted.', 'notifier' ),
        ), 200 );
    }

    // ========================================
    // 11. REST HANDLERS — MIGRATION
    // ========================================

    public static function rest_get_migration_status() {
        $is_complete      = Notifier_Migration::is_migration_complete();
        $has_legacy       = Notifier_Migration::has_legacy_triggers();
        $slugs            = Notifier_Migration::get_non_woo_slugs_with_legacy_triggers();
        $all_connected    = Notifier_Migration::all_non_woo_slugs_connected();
        $migrate_url      = Notifier_Migration::get_migrate_connect_url();
        $trigger_scenario = Notifier_Migration::get_trigger_scenario();

        $trigger_posts = array();
        if ( $has_legacy ) {
            $integrations = self::get_integrations();

            $posts = get_posts( array(
                'post_type'   => 'wa_notifier_trigger',
                'post_status' => 'publish',
                'numberposts' => -1,
            ) );

            $all_triggers = Notifier_Notification_Triggers::get_notification_triggers();
            $trigger_label_map = array();
            foreach ( $all_triggers as $group => $triggers ) {
                foreach ( $triggers as $t ) {
                    $base = Notifier_Notification_Triggers::get_trigger_id_without_site_key( $t['id'] );
                    $trigger_label_map[ $base ] = $t['label'];
                }
            }

            foreach ( $posts as $post ) {
                $trigger_id   = get_post_meta( $post->ID, NOTIFIER_PREFIX . 'trigger', true );
                $base_trigger = Notifier_Notification_Triggers::get_trigger_id_without_site_key( $trigger_id );
                $slug         = Notifier_Notification_Triggers::get_integration_slug_for_trigger( $base_trigger );
                $is_woo       = in_array( $slug, Notifier_Migration::WOO_SLUGS, true );
                $connected    = $slug ? Notifier_Connection::is_connected( $slug ) : false;
                $label        = isset( $integrations[ $slug ]['label'] ) ? $integrations[ $slug ]['label'] : ucfirst( $slug ?: 'Unknown' );
                $trigger_label = isset( $trigger_label_map[ $base_trigger ] ) ? $trigger_label_map[ $base_trigger ] : $base_trigger;

                $trigger_posts[] = array(
                    'id'           => $post->ID,
                    'title'        => $trigger_label,
                    'slug'         => $slug ?: 'unknown',
                    'label'        => $label,
                    'is_connected' => $connected,
                    'is_woo'       => $is_woo,
                );
            }
        }

        return new WP_REST_Response( array(
            'is_complete'      => $is_complete,
            'has_legacy'       => $has_legacy,
            'slugs'            => $slugs,
            'all_connected'    => $all_connected,
            'migrate_url'      => $migrate_url,
            'trigger_posts'    => $trigger_posts,
            'trigger_scenario' => $trigger_scenario,
            'integrations_url' => admin_url( 'admin.php?page=notifier' ),
        ), 200 );
    }

    public static function rest_finalize_migration() {
        if ( ! Notifier_Migration::all_non_woo_slugs_connected() ) {
            return new WP_REST_Response( array(
                'success' => false,
                'message' => __( 'Not all integrations are connected yet.', 'notifier' ),
            ), 400 );
        }

        $api_key = trim( get_option( 'notifier_api_key', '' ) );
        if ( $api_key ) {
            Notifier_Migration::disconnect_legacy_on_saas( $api_key );
        }

        Notifier_Migration::delete_legacy_trigger_posts();

        update_option( Notifier_Migration::STATUS_OPTION, 'complete' );

        return new WP_REST_Response( array(
            'success'  => true,
            'message'  => __( 'Migration complete!', 'notifier' ),
            'redirect' => admin_url( 'admin.php?page=notifier' ),
        ), 200 );
    }


    // ========================================
    // 12b. REST HANDLER — WORDPRESS META FIELDS
    // ========================================

    public static function rest_get_wp_available_meta_fields( $request ) {
        $show_hidden = rest_sanitize_boolean( $request->get_param( 'show_hidden' ) );
        $groups     = array();

        // Single "Post Meta" group: all custom meta keys from all public post types (option stores all; filter by show_hidden).
        $combined = Notifier_Notification_Merge_Tags::get_custom_meta_keys( null );
        if ( ! empty( $combined ) ) {
            $post_meta = array();
            foreach ( $combined as $item ) {
                if ( ! $show_hidden && isset( $item['key'] ) && substr( (string) $item['key'], 0, 1 ) === '_' ) {
                    continue;
                }
                $post_meta[] = array(
                    'id'          => $item['post_type'] . '_meta_' . $item['key'],
                    'label'       => $item['key'],
                    'return_type' => 'all',
                );
            }
            if ( ! empty( $post_meta ) ) {
                $groups['Post Meta'] = $post_meta;
            }
        }

        // User meta group (option stores all; filter by show_hidden).
        $user_keys = Notifier_Notification_Merge_Tags::get_user_meta_keys();
        if ( ! empty( $user_keys ) && is_array( $user_keys ) ) {
            $user_meta = array();
            foreach ( $user_keys as $key ) {
                if ( ! $show_hidden && substr( (string) $key, 0, 1 ) === '_' ) {
                    continue;
                }
                $user_meta[] = array(
                    'id'          => 'user_meta_' . $key,
                    'label'       => $key,
                    'return_type' => 'all',
                );
            }
            if ( ! empty( $user_meta ) ) {
                $groups['User Meta'] = $user_meta;
            }
        }

        // Hook-added fields: exclude groups that are builtin (from merge tags / trigger definitions).
        $hook_fields = self::get_hook_added_merge_tag_fields();
        foreach ( $hook_fields as $field ) {
            $group = isset( $field['group'] ) ? $field['group'] : 'Custom Fields';
            if ( ! isset( $groups[ $group ] ) ) {
                $groups[ $group ] = array();
            }
            $groups[ $group ][] = array(
                'id'          => $field['id'],
                'label'       => isset( $field['label'] ) ? $field['label'] : $field['id'],
                'return_type' => isset( $field['return_type'] ) ? $field['return_type'] : 'text',
            );
        }

        return new WP_REST_Response( array( 'groups' => $groups ), 200 );
    }

    /**
     * POST /admin/sync-meta-fields — Sync all post and user meta keys from DB into options (normal + hidden).
     * Call this to refresh the meta field list when new meta is added on the site.
     */
    public static function rest_sync_meta_fields() {
        delete_option( 'notifier_custom_meta_keys' );
        delete_option( 'notifier_user_meta_keys' );
        Notifier_Notification_Merge_Tags::get_custom_meta_keys( null );
        Notifier_Notification_Merge_Tags::get_user_meta_keys();
        return new WP_REST_Response( array(
            'success' => true,
            'message' => __( 'Meta fields synced. The list now includes all current post and user meta keys.', 'notifier' ),
        ), 200 );
    }

    /**
     * Return merge tag fields added via the notifier_notification_merge_tags filter
     * that are not part of the built-in groups.
     *
     * @return array[] Array of { group, id, label } objects.
     */
    private static function get_hook_added_merge_tag_fields() {
        // Builtin groups from merge tags / trigger definitions so we exclude them from the Data Fields dropdown.
        $all_tags       = apply_filters( 'notifier_notification_merge_tags', array() );
        $builtin_groups = array_merge( array( 'WordPress' ), array_keys( $all_tags ) );
        $fields         = array();

        foreach ( $all_tags as $group => $tags ) {
            if ( in_array( $group, $builtin_groups, true ) ) {
                continue;
            }
            foreach ( (array) $tags as $tag ) {
                if ( empty( $tag['id'] ) ) {
                    continue;
                }
                $fields[] = array(
                    'group' => $group,
                    'id'    => $tag['id'],
                    'label' => isset( $tag['label'] ) ? $tag['label'] : $tag['id'],
                );
            }
        }

        return $fields;
    }

    // ========================================
    // 13. INTEGRATION DEFINITIONS
    // ========================================

    public static function get_integrations() {
        $img          = NOTIFIER_URL . 'assets/images/integrations/';
        $woo_handled  = Notifier::is_woo_handled_by_standalone_plugin();

        return array(
            'woocommerce' => array(
                'label'                 => 'WooCommerce',
                'description'           => __( 'Order notifications and customer sync', 'notifier' ),
                'icon'                  => $img . 'woocommerce-logo.png',
                'active'                => class_exists( 'WooCommerce' ),
                'has_config'            => $woo_handled ? false : true,
                'config_component'      => $woo_handled ? '' : 'WooCommerceConfig',
                'handled_by_standalone' => $woo_handled,
            ),
            'wcar' => array(
                'label'                 => 'Cart Abandonment Recovery for WooCommerce',
                'description'           => __( 'Send notifications when a cart is abandoned', 'notifier' ),
                'icon'                  => $img . 'wcar-logo.svg',
                'active'                => class_exists( 'CARTFLOWS_CA_Loader' ) && defined( 'CARTFLOWS_CA_VER' ) && version_compare( CARTFLOWS_CA_VER, '1.2.25', '>=' ),
                'has_config'            => false,
                'handled_by_standalone' => $woo_handled,
            ),
            'wordpress' => array(
                'label'            => 'WordPress',
                'description'      => __( 'Posts, users, comments and more', 'notifier' ),
                'icon'             => $img . 'wordpress-logo.png',
                'active'           => true,
                'has_config'       => true,
                'config_component' => 'WordPressConfig',
            ),
            'gravityforms' => array(
                'label'       => 'Gravity Forms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'gravity-forms-logo.png',
                'active'      => class_exists( 'GFCommon' ),
                'has_config'  => false,
            ),
            'cf7' => array(
                'label'       => 'Contact Form 7',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'contact-form-7-logo.png',
                'active'      => class_exists( 'WPCF7' ),
                'has_config'  => false,
            ),
            'wpforms' => array(
                'label'       => 'WPForms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'wpforms-logo.png',
                'active'      => class_exists( 'WPForms' ),
                'has_config'  => false,
            ),
            'ninjaforms' => array(
                'label'       => 'Ninja Forms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'nf-logo.png',
                'active'      => class_exists( 'Ninja_Forms' ),
                'has_config'  => false,
            ),
            'formidable' => array(
                'label'       => 'Formidable Forms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'formidable-logo.png',
                'active'      => class_exists( 'FrmForm' ),
                'has_config'  => false,
            ),
            'fluentforms' => array(
                'label'       => 'Fluent Forms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'fluent-forms-logo.webp',
                'active'      => function_exists( 'fluentFormApi' ),
                'has_config'  => false,
            ),
            'forminator' => array(
                'label'       => 'Forminator Forms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'forminator-form-logo.svg',
                'active'      => class_exists( 'Forminator' ),
                'has_config'  => false,
            ),
            'sureforms' => array(
                'label'       => 'SureForms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'sureform-logo.svg',
                'active'      => class_exists( 'SRFM\Plugin_Loader' ),
                'has_config'  => false,
            ),
            'wsform' => array(
                'label'       => 'WS Forms',
                'description' => __( 'Form submission notifications', 'notifier' ),
                'icon'        => $img . 'ws-form-logo.svg',
                'active'      => class_exists( 'WS_Form' ),
                'has_config'  => false,
            ),
        );
    }

    // ========================================
    // 14. SETTINGS DATA
    // ========================================

    public static function get_all_settings() {
        return array(
            'default_country_code'              => get_option( 'notifier_default_country_code', '' ),
            'disable_background_processing'     => get_option( 'notifier_disable_background_processing', 'no' ),
            'ctc_enable'                        => get_option( 'notifier_ctc_enable', 'no' ),
            'ctc_whatsapp_number'               => get_option( 'notifier_ctc_whatsapp_number', '' ),
            'ctc_greeting_text'                 => get_option( 'notifier_ctc_greeting_text', '' ),
            'ctc_button_style'                  => get_option( 'notifier_ctc_button_style', 'default' ),
            'ctc_custom_button_image_url'       => get_option( 'notifier_ctc_custom_button_image_url', '' ),
            'ctc_position'                      => get_option( 'notifier_ctc_position', 'bottom-right' ),
            'ctc_offset_x'                      => get_option( 'notifier_ctc_offset_x', 20 ),
            'ctc_offset_y'                      => get_option( 'notifier_ctc_offset_y', 20 ),
            'ctc_mobile_position_enable'        => get_option( 'notifier_ctc_mobile_position_enable', 'no' ),
            'ctc_mobile_position'               => get_option( 'notifier_ctc_mobile_position', 'bottom-right' ),
            'ctc_mobile_offset_x'               => get_option( 'notifier_ctc_mobile_offset_x', 20 ),
            'ctc_mobile_offset_y'               => get_option( 'notifier_ctc_mobile_offset_y', 20 ),
            'ctc_display_rules'                 => self::get_ctc_display_rules_for_ui(),
            'ctc_devices'                       => get_option( 'notifier_ctc_devices', array_keys( self::get_ctc_device_options() ) ),
            'enable_activity_log'               => get_option( 'notifier_enable_activity_log', 'no' ),
            'wp_enabled_merge_tags'             => get_option( 'notifier_wp_enabled_merge_tags', array() ),
            'wp_enabled_recipient_fields'       => get_option( 'notifier_wp_enabled_recipient_fields', array() ),
            'button_styles'                     => self::get_button_styles(),
            'ctc_position_options'              => self::get_ctc_position_options(),
            'ctc_location_options'              => self::get_ctc_location_options(),
            'ctc_device_options'                => self::get_ctc_device_options(),
        );
    }

    private static function get_settings_field_definitions() {
        return array(
            'default_country_code'            => array( 'type' => 'text' ),
            'disable_background_processing'   => array( 'type' => 'checkbox' ),
            'ctc_enable'                      => array( 'type' => 'checkbox' ),
            'ctc_whatsapp_number'             => array( 'type' => 'text' ),
            'ctc_greeting_text'               => array( 'type' => 'text' ),
            'ctc_button_style'                => array( 'type' => 'select', 'options' => self::get_button_styles(), 'default' => 'default' ),
            'ctc_custom_button_image_url'     => array( 'type' => 'text' ),
            'ctc_position'                    => array( 'type' => 'select', 'options' => self::get_ctc_position_options(), 'default' => 'bottom-right' ),
            'ctc_offset_x'                    => array( 'type' => 'number', 'min' => 0 ),
            'ctc_offset_y'                    => array( 'type' => 'number', 'min' => 0 ),
            'ctc_mobile_position_enable'      => array( 'type' => 'checkbox' ),
            'ctc_mobile_position'             => array( 'type' => 'select', 'options' => self::get_ctc_position_options(), 'default' => 'bottom-right' ),
            'ctc_mobile_offset_x'             => array( 'type' => 'number', 'min' => 0 ),
            'ctc_mobile_offset_y'             => array( 'type' => 'number', 'min' => 0 ),
            'ctc_display_rules'               => array( 'type' => 'display_rules' ),
            'ctc_devices'                     => array( 'type' => 'array', 'options' => self::get_ctc_device_options() ),
            'enable_activity_log'             => array( 'type' => 'checkbox' ),
            'wp_enabled_merge_tags'           => array( 'type' => 'array' ),
            'wp_enabled_recipient_fields'     => array( 'type' => 'array' ),
        );
    }

    public static function get_button_styles() {
        return array(
            'default'          => 'Select button style',
            'btn-style-1'     => 'Style 1',
            'btn-style-2'     => 'Style 2',
            'btn-style-3'     => 'Style 3',
            'btn-style-4'     => 'Style 4',
            'btn-custom-image' => 'Add your own image',
        );
    }

    public static function get_ctc_position_options() {
        return array(
            'bottom-right' => 'Bottom Right',
            'bottom-left'  => 'Bottom Left',
            'top-right'    => 'Top Right',
            'top-left'     => 'Top Left',
        );
    }

    // ----------------------------------------
    // Chat button display rules
    // ----------------------------------------

    /**
     * Grouped location options for the display / exclude rule dropdowns (react-select format).
     *
     * Rule keys:
     *  basic-global | basic-singulars | basic-archives
     *  special-front | special-blog | special-404 | special-search | special-date | special-author
     *  {post_type}|all | {post_type}|archive | {post_type}|tax|{taxonomy}
     *  wc-shop | wc-cart | wc-checkout | wc-account | wc-order-received
     *  specifics  (with items: post-{id}, tax-{term_id}, tax-{term_id}-posts)
     */
    public static function get_ctc_location_options() {
        $groups = array(
            array(
                'label'   => 'Basic',
                'options' => array(
                    array('value' => 'basic-global',    'label' => 'Entire Website'),
                    array('value' => 'basic-singulars', 'label' => 'All Singulars'),
                    array('value' => 'basic-archives',  'label' => 'All Archives'),
                ),
            ),
            array(
                'label'   => 'Special Pages',
                'options' => array(
                    array('value' => 'special-front',  'label' => 'Front Page'),
                    array('value' => 'special-blog',   'label' => 'Blog / Posts Page'),
                    array('value' => 'special-404',    'label' => '404 Page'),
                    array('value' => 'special-search', 'label' => 'Search Results'),
                    array('value' => 'special-date',   'label' => 'Date Archive'),
                    array('value' => 'special-author', 'label' => 'Author Archive'),
                ),
            ),
        );

        $has_woo = class_exists('WooCommerce');

        foreach (self::get_ctc_rule_post_types() as $post_type) {
            $options = array(
                array('value' => $post_type->name . '|all', 'label' => 'All ' . $post_type->labels->name),
            );

            // The product archive is the WooCommerce shop page, listed under WooCommerce below.
            if ($post_type->has_archive && ! ($has_woo && 'product' === $post_type->name)) {
                $options[] = array('value' => $post_type->name . '|archive', 'label' => $post_type->labels->name . ' Archive');
            }

            foreach (get_object_taxonomies($post_type->name, 'objects') as $taxonomy) {
                if (! self::is_ctc_rule_taxonomy($taxonomy)) {
                    continue;
                }
                $options[] = array(
                    'value' => $post_type->name . '|tax|' . $taxonomy->name,
                    'label' => 'All ' . $taxonomy->labels->singular_name . ' Archives',
                );
            }

            $groups[] = array('label' => $post_type->labels->name, 'options' => $options);
        }

        if ($has_woo) {
            $groups[] = array(
                'label'   => 'WooCommerce',
                'options' => array(
                    array('value' => 'wc-shop',           'label' => 'Shop Page'),
                    array('value' => 'wc-cart',           'label' => 'Cart Page'),
                    array('value' => 'wc-checkout',       'label' => 'Checkout Page'),
                    array('value' => 'wc-account',        'label' => 'My Account Page'),
                    array('value' => 'wc-order-received', 'label' => 'Order Received (Thank You) Page'),
                ),
            );
        }

        $groups[] = array(
            'label'   => 'Specific Target',
            'options' => array(
                array('value' => 'specifics', 'label' => 'Specific Pages / Posts / Taxonomies'),
            ),
        );

        return $groups;
    }

    /**
     * Flat list of valid rule keys.
     */
    public static function get_ctc_location_keys() {
        $keys = array();
        foreach (self::get_ctc_location_options() as $group) {
            foreach ($group['options'] as $option) {
                $keys[] = $option['value'];
            }
        }
        return $keys;
    }

    /**
     * Public, frontend-viewable post types that rules can target.
     *
     * @return WP_Post_Type[]
     */
    public static function get_ctc_rule_post_types() {
        $post_types = array();
        foreach (get_post_types(array('public' => true), 'objects') as $post_type) {
            if ('attachment' === $post_type->name || ! is_post_type_viewable($post_type)) {
                continue;
            }
            $post_types[] = $post_type;
        }
        return $post_types;
    }

    /**
     * Whether a taxonomy has frontend archives worth targeting.
     *
     * @param WP_Taxonomy $taxonomy
     */
    public static function is_ctc_rule_taxonomy($taxonomy) {
        // Post formats and WooCommerce shipping classes are queryable but have no real archive pages.
        if (in_array($taxonomy->name, array('post_format', 'product_shipping_class'), true)) {
            return false;
        }
        return is_taxonomy_viewable($taxonomy);
    }

    public static function get_default_ctc_display_rules() {
        return array(
            'display' => array(array('rule' => 'basic-global', 'specifics' => array())),
            'exclude' => array(),
        );
    }

    /**
     * Validate submitted rules: unknown rule keys and malformed specific items are dropped,
     * as are "Specific" rows with nothing selected.
     */
    public static function sanitize_ctc_display_rules($value) {
        $valid = self::get_ctc_location_keys();
        $clean = array('display' => array(), 'exclude' => array());

        foreach (array('display', 'exclude') as $list) {
            if (empty($value[$list]) || ! is_array($value[$list])) {
                continue;
            }
            foreach ($value[$list] as $row) {
                $rule = isset($row['rule']) ? sanitize_text_field((string) $row['rule']) : '';
                if (! in_array($rule, $valid, true)) {
                    continue;
                }

                $specifics = array();
                if ('specifics' === $rule) {
                    foreach ((array) ($row['specifics'] ?? array()) as $item) {
                        $item = is_array($item) ? ($item['value'] ?? '') : $item;
                        if (preg_match('/^(post|tax)-\d+(-posts)?$/', (string) $item)) {
                            $specifics[] = (string) $item;
                        }
                    }
                    if (empty($specifics)) {
                        continue;
                    }
                }

                $clean[$list][] = array('rule' => $rule, 'specifics' => array_values(array_unique($specifics)));
            }
        }

        return $clean;
    }

    /**
     * Saved rules (raw keys), falling back to "Entire Website".
     */
    public static function get_ctc_display_rules() {
        $rules = get_option('notifier_ctc_display_rules', null);
        if (! is_array($rules) || ! isset($rules['display'])) {
            return self::get_default_ctc_display_rules();
        }
        return wp_parse_args($rules, array('display' => array(), 'exclude' => array()));
    }

    /**
     * Saved rules with the specific items expanded to {value,label} options for the settings UI.
     * Items whose post/term no longer exists are left out.
     */
    public static function get_ctc_display_rules_for_ui() {
        $rules = self::get_ctc_display_rules();
        foreach ($rules as &$rows) {
            foreach ($rows as &$row) {
                $row['specifics'] = array_values(array_filter(array_map(array(__CLASS__, 'get_ctc_specific_option'), (array) $row['specifics'])));
            }
            unset($row);
        }
        unset($rows);
        return $rules;
    }

    /**
     * Build the {value,label} option for a specific item key (post-{id}, tax-{id}, tax-{id}-posts).
     *
     * @return array|null Null if the post/term no longer exists.
     */
    public static function get_ctc_specific_option($key) {
        if (! preg_match('/^(post|tax)-(\d+)(-posts)?$/', (string) $key, $m)) {
            return null;
        }
        $id = (int) $m[2];

        if ('post' === $m[1]) {
            $post = get_post($id);
            if (! $post || 'trash' === $post->post_status) {
                return null;
            }
            $type  = get_post_type_object($post->post_type);
            // Plain text: React renders labels as text nodes, so entities from wptexturize/kses would show literally.
            $title = trim(html_entity_decode(wp_strip_all_tags($post->post_title), ENT_QUOTES, 'UTF-8'));
            return array(
                'value' => $key,
                'label' => ('' !== $title ? $title : '#' . $id) . ' (' . ($type ? $type->labels->singular_name : $post->post_type) . ')',
            );
        }

        $term = get_term($id);
        if (! $term || is_wp_error($term)) {
            return null;
        }
        $taxonomy  = get_taxonomy($term->taxonomy);
        $tax_label = $taxonomy ? $taxonomy->labels->singular_name : $term->taxonomy;
        $term_name = html_entity_decode($term->name, ENT_QUOTES, 'UTF-8');

        return array(
            'value' => $key,
            'label' => ! empty($m[3])
                ? sprintf('%s (%s) – all items in it', $term_name, $tax_label)
                : sprintf('%s (%s) – archive page', $term_name, $tax_label),
        );
    }

    /**
     * Search posts (all public post types) and terms (all public taxonomies) for the
     * "Specific Pages / Posts / Taxonomies" picker. Returns react-select option groups.
     */
    public static function rest_search_content(WP_REST_Request $request) {
        $query  = trim(sanitize_text_field((string) $request->get_param('q')));
        $groups = array();

        foreach (self::get_ctc_rule_post_types() as $post_type) {
            $args = array(
                'post_type'        => $post_type->name,
                'post_status'      => 'publish',
                'posts_per_page'   => 10,
                'orderby'          => '' !== $query ? 'relevance' : 'title',
                'order'            => 'ASC',
                'fields'           => 'ids',
                'no_found_rows'    => true,
            );
            if ('' !== $query) {
                $args['s'] = $query;
            }
            $ids = get_posts($args);

            // Allow pasting an ID directly (published items only, like the search results).
            if (is_numeric($query) && get_post_type((int) $query) === $post_type->name && 'publish' === get_post_status((int) $query)) {
                array_unshift($ids, (int) $query);
            }

            $options = array();
            foreach (array_unique(array_map('intval', $ids)) as $id) {
                $option = self::get_ctc_specific_option('post-' . $id);
                if ($option) {
                    $options[] = $option;
                }
            }
            if (! empty($options)) {
                $groups[] = array('label' => $post_type->labels->name, 'options' => $options);
            }
        }

        foreach (get_taxonomies(array('public' => true), 'objects') as $taxonomy) {
            if (! self::is_ctc_rule_taxonomy($taxonomy)) {
                continue;
            }
            $args = array(
                'taxonomy'   => $taxonomy->name,
                'hide_empty' => false,
                'number'     => 10,
                'orderby'    => 'name',
            );
            if ('' !== $query) {
                $args['search'] = $query;
            }
            $terms = get_terms($args);
            if (is_wp_error($terms) || empty($terms)) {
                continue;
            }

            $options = array();
            foreach ($terms as $term) {
                foreach (array('tax-' . $term->term_id, 'tax-' . $term->term_id . '-posts') as $key) {
                    $option = self::get_ctc_specific_option($key);
                    if ($option) {
                        $options[] = $option;
                    }
                }
            }
            $groups[] = array('label' => $taxonomy->labels->name, 'options' => $options);
        }

        return new WP_REST_Response($groups, 200);
    }

    public static function get_ctc_device_options() {
        return array(
            'desktop' => 'Desktop',
            'tablet'  => 'Tablet',
            'mobile'  => 'Mobile',
        );
    }

    // ========================================
    // 15. ACTIVITY LOG
    // ========================================

    public static function insert_activity_log( $type = 'debug', $message = '' ) {
        if ( 'yes' !== get_option( 'notifier_enable_activity_log' ) ) {
            return;
        }

        global $wpdb;
        $table_name = $wpdb->prefix . NOTIFIER_ACTIVITY_TABLE_NAME;

        $wpdb->insert( $table_name, array(
            'timestamp' => current_time( 'mysql', true ),
            'message'   => $message,
            'type'      => $type,
        ), array( '%s', '%s', '%s' ) );
    }
}