Implement Phase 9: Prometheus Metrics (v0.9.0)

- Add Prometheus metrics integration via wp-prometheus hooks
- Create Grafana dashboard JSON with 24 panels
- Add metrics settings tab with enable/disable toggle
- Expose inventory, booking, occupancy, revenue, and guest metrics

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/Integration/Prometheus.php

@@ -0,0 +1,877 @@
+<?php
+/**
+ * Prometheus Metrics Integration.
+ *
+ * Provides meaningful metrics for monitoring BnB operations.
+ *
+ * @package Magdev\WpBnb\Integration
+ */
+
+declare( strict_types=1 );
+
+namespace Magdev\WpBnb\Integration;
+
+use Magdev\WpBnb\PostTypes\Booking;
+use Magdev\WpBnb\PostTypes\Building;
+use Magdev\WpBnb\PostTypes\Guest;
+use Magdev\WpBnb\PostTypes\Room;
+use Magdev\WpBnb\PostTypes\Service;
+
+/**
+ * Prometheus Metrics Integration class.
+ *
+ * Exposes BnB metrics via the wp-prometheus plugin.
+ */
+class Prometheus {
+
+	/**
+	 * Option key for enabling metrics.
+	 */
+	public const OPTION_ENABLED = 'wp_bnb_metrics_enabled';
+
+	/**
+	 * Initialize the Prometheus integration.
+	 *
+	 * @return void
+	 */
+	public static function init(): void {
+		// Only hook if metrics are enabled.
+		if ( ! self::is_enabled() ) {
+			return;
+		}
+
+		// Hook into wp-prometheus collector.
+		add_action( 'wp_prometheus_collect_metrics', array( self::class, 'collect_metrics' ) );
+
+		// Register Grafana dashboard.
+		add_action( 'wp_prometheus_register_dashboards', array( self::class, 'register_dashboards' ) );
+	}
+
+	/**
+	 * Check if metrics collection is enabled.
+	 *
+	 * @return bool
+	 */
+	public static function is_enabled(): bool {
+		return 'yes' === get_option( self::OPTION_ENABLED, 'yes' );
+	}
+
+	/**
+	 * Enable metrics collection.
+	 *
+	 * @return void
+	 */
+	public static function enable(): void {
+		update_option( self::OPTION_ENABLED, 'yes' );
+	}
+
+	/**
+	 * Disable metrics collection.
+	 *
+	 * @return void
+	 */
+	public static function disable(): void {
+		update_option( self::OPTION_ENABLED, 'no' );
+	}
+
+	/**
+	 * Collect and register all BnB metrics.
+	 *
+	 * @param object $collector The wp-prometheus collector instance.
+	 * @return void
+	 */
+	public static function collect_metrics( $collector ): void {
+		self::collect_inventory_metrics( $collector );
+		self::collect_booking_metrics( $collector );
+		self::collect_guest_metrics( $collector );
+		self::collect_occupancy_metrics( $collector );
+		self::collect_revenue_metrics( $collector );
+	}
+
+	/**
+	 * Collect inventory metrics (buildings, rooms, services).
+	 *
+	 * @param object $collector The wp-prometheus collector instance.
+	 * @return void
+	 */
+	private static function collect_inventory_metrics( $collector ): void {
+		// Buildings total.
+		$buildings_total = wp_count_posts( Building::POST_TYPE );
+		$gauge           = $collector->register_gauge(
+			'wp_bnb_buildings_total',
+			'Total number of buildings',
+			array()
+		);
+		$gauge->set( (int) $buildings_total->publish, array() );
+
+		// Rooms by status.
+		$rooms_gauge = $collector->register_gauge(
+			'wp_bnb_rooms_total',
+			'Total number of rooms by status',
+			array( 'status' )
+		);
+
+		$room_statuses = array( 'available', 'occupied', 'maintenance', 'inactive' );
+		foreach ( $room_statuses as $status ) {
+			$count = self::count_rooms_by_status( $status );
+			$rooms_gauge->set( $count, array( $status ) );
+		}
+
+		// Services by status.
+		$services_gauge = $collector->register_gauge(
+			'wp_bnb_services_total',
+			'Total number of services by status',
+			array( 'status' )
+		);
+
+		$service_statuses = array( 'active', 'inactive' );
+		foreach ( $service_statuses as $status ) {
+			$count = self::count_services_by_status( $status );
+			$services_gauge->set( $count, array( $status ) );
+		}
+	}
+
+	/**
+	 * Collect booking metrics.
+	 *
+	 * @param object $collector The wp-prometheus collector instance.
+	 * @return void
+	 */
+	private static function collect_booking_metrics( $collector ): void {
+		// Bookings by status.
+		$bookings_gauge = $collector->register_gauge(
+			'wp_bnb_bookings_total',
+			'Total number of bookings by status',
+			array( 'status' )
+		);
+
+		$booking_statuses = array( 'pending', 'confirmed', 'checked_in', 'checked_out', 'cancelled' );
+		foreach ( $booking_statuses as $status ) {
+			$count = self::count_bookings_by_status( $status );
+			$bookings_gauge->set( $count, array( $status ) );
+		}
+
+		// Today's check-ins.
+		$checkins_gauge = $collector->register_gauge(
+			'wp_bnb_checkins_today',
+			'Number of check-ins scheduled for today',
+			array()
+		);
+		$checkins_gauge->set( self::count_todays_checkins(), array() );
+
+		// Today's check-outs.
+		$checkouts_gauge = $collector->register_gauge(
+			'wp_bnb_checkouts_today',
+			'Number of check-outs scheduled for today',
+			array()
+		);
+		$checkouts_gauge->set( self::count_todays_checkouts(), array() );
+
+		// Upcoming bookings (next 7 days).
+		$upcoming_gauge = $collector->register_gauge(
+			'wp_bnb_bookings_upcoming_7days',
+			'Number of bookings starting in the next 7 days',
+			array()
+		);
+		$upcoming_gauge->set( self::count_upcoming_bookings( 7 ), array() );
+
+		// Average booking duration (nights).
+		$avg_duration = $collector->register_gauge(
+			'wp_bnb_booking_avg_duration_nights',
+			'Average booking duration in nights',
+			array()
+		);
+		$avg_duration->set( self::get_average_booking_duration(), array() );
+	}
+
+	/**
+	 * Collect guest metrics.
+	 *
+	 * @param object $collector The wp-prometheus collector instance.
+	 * @return void
+	 */
+	private static function collect_guest_metrics( $collector ): void {
+		// Total guests.
+		$guests_total = wp_count_posts( Guest::POST_TYPE );
+		$guests_gauge = $collector->register_gauge(
+			'wp_bnb_guests_total',
+			'Total number of registered guests',
+			array()
+		);
+		$guests_gauge->set( (int) $guests_total->publish, array() );
+
+		// Guests by status.
+		$guests_status_gauge = $collector->register_gauge(
+			'wp_bnb_guests_by_status',
+			'Number of guests by status',
+			array( 'status' )
+		);
+
+		$guest_statuses = array( 'active', 'blocked', 'vip' );
+		foreach ( $guest_statuses as $status ) {
+			$count = self::count_guests_by_status( $status );
+			$guests_status_gauge->set( $count, array( $status ) );
+		}
+
+		// Repeat guests (guests with more than one booking).
+		$repeat_gauge = $collector->register_gauge(
+			'wp_bnb_guests_repeat',
+			'Number of guests with more than one booking',
+			array()
+		);
+		$repeat_gauge->set( self::count_repeat_guests(), array() );
+
+		// New guests this month.
+		$new_guests_gauge = $collector->register_gauge(
+			'wp_bnb_guests_new_this_month',
+			'Number of new guests registered this month',
+			array()
+		);
+		$new_guests_gauge->set( self::count_new_guests_this_month(), array() );
+	}
+
+	/**
+	 * Collect occupancy metrics.
+	 *
+	 * @param object $collector The wp-prometheus collector instance.
+	 * @return void
+	 */
+	private static function collect_occupancy_metrics( $collector ): void {
+		// Current occupancy rate (percentage).
+		$occupancy_gauge = $collector->register_gauge(
+			'wp_bnb_occupancy_rate_current',
+			'Current room occupancy rate (percentage)',
+			array()
+		);
+		$occupancy_gauge->set( self::get_current_occupancy_rate(), array() );
+
+		// Occupancy rate this month.
+		$occupancy_month_gauge = $collector->register_gauge(
+			'wp_bnb_occupancy_rate_this_month',
+			'Room occupancy rate for the current month (percentage)',
+			array()
+		);
+		$occupancy_month_gauge->set( self::get_monthly_occupancy_rate(), array() );
+
+		// Rooms currently occupied.
+		$occupied_gauge = $collector->register_gauge(
+			'wp_bnb_rooms_currently_occupied',
+			'Number of rooms currently occupied',
+			array()
+		);
+		$occupied_gauge->set( self::count_currently_occupied_rooms(), array() );
+
+		// Total room capacity (beds).
+		$capacity_gauge = $collector->register_gauge(
+			'wp_bnb_total_capacity_beds',
+			'Total bed capacity across all rooms',
+			array()
+		);
+		$capacity_gauge->set( self::get_total_bed_capacity(), array() );
+	}
+
+	/**
+	 * Collect revenue metrics.
+	 *
+	 * @param object $collector The wp-prometheus collector instance.
+	 * @return void
+	 */
+	private static function collect_revenue_metrics( $collector ): void {
+		$currency = get_option( 'wp_bnb_currency', 'CHF' );
+
+		// Revenue this month.
+		$revenue_month_gauge = $collector->register_gauge(
+			'wp_bnb_revenue_this_month',
+			'Total revenue for the current month',
+			array( 'currency' )
+		);
+		$revenue_month_gauge->set( self::get_revenue_this_month(), array( $currency ) );
+
+		// Revenue year to date.
+		$revenue_ytd_gauge = $collector->register_gauge(
+			'wp_bnb_revenue_ytd',
+			'Total revenue year to date',
+			array( 'currency' )
+		);
+		$revenue_ytd_gauge->set( self::get_revenue_ytd(), array( $currency ) );
+
+		// Average booking value.
+		$avg_value_gauge = $collector->register_gauge(
+			'wp_bnb_booking_avg_value',
+			'Average booking value',
+			array( 'currency' )
+		);
+		$avg_value_gauge->set( self::get_average_booking_value(), array( $currency ) );
+
+		// Revenue from services this month.
+		$services_revenue_gauge = $collector->register_gauge(
+			'wp_bnb_services_revenue_this_month',
+			'Revenue from additional services this month',
+			array( 'currency' )
+		);
+		$services_revenue_gauge->set( self::get_services_revenue_this_month(), array( $currency ) );
+	}
+
+	/**
+	 * Register Grafana dashboards.
+	 *
+	 * @param object $provider The wp-prometheus dashboard provider instance.
+	 * @return void
+	 */
+	public static function register_dashboards( $provider ): void {
+		$dashboard_file = WP_BNB_PATH . 'assets/grafana/wp-bnb-dashboard.json';
+
+		if ( file_exists( $dashboard_file ) ) {
+			$provider->register_dashboard(
+				'wp-bnb',
+				array(
+					'title'       => __( 'WP BnB Dashboard', 'wp-bnb' ),
+					'description' => __( 'Monitor occupancy, bookings, revenue, and guest statistics for your B&B.', 'wp-bnb' ),
+					'icon'        => 'dashicons-building',
+					'file'        => $dashboard_file,
+					'plugin'      => 'WP BnB Manager',
+				)
+			);
+		}
+	}
+
+	// =========================================================================
+	// Helper Methods - Inventory
+	// =========================================================================
+
+	/**
+	 * Count rooms by status.
+	 *
+	 * @param string $status Room status.
+	 * @return int
+	 */
+	private static function count_rooms_by_status( string $status ): int {
+		global $wpdb;
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm ON p.ID = pm.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm.meta_key = '_bnb_room_status'
+				AND pm.meta_value = %s",
+				Room::POST_TYPE,
+				$status
+			)
+		);
+	}
+
+	/**
+	 * Count services by status.
+	 *
+	 * @param string $status Service status.
+	 * @return int
+	 */
+	private static function count_services_by_status( string $status ): int {
+		global $wpdb;
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm ON p.ID = pm.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm.meta_key = '_bnb_service_status'
+				AND pm.meta_value = %s",
+				Service::POST_TYPE,
+				$status
+			)
+		);
+	}
+
+	// =========================================================================
+	// Helper Methods - Bookings
+	// =========================================================================
+
+	/**
+	 * Count bookings by status.
+	 *
+	 * @param string $status Booking status.
+	 * @return int
+	 */
+	private static function count_bookings_by_status( string $status ): int {
+		global $wpdb;
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm ON p.ID = pm.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm.meta_key = '_bnb_booking_status'
+				AND pm.meta_value = %s",
+				Booking::POST_TYPE,
+				$status
+			)
+		);
+	}
+
+	/**
+	 * Count today's check-ins.
+	 *
+	 * @return int
+	 */
+	private static function count_todays_checkins(): int {
+		global $wpdb;
+		$today = gmdate( 'Y-m-d' );
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_date ON p.ID = pm_date.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_date.meta_key = '_bnb_booking_check_in'
+				AND pm_date.meta_value = %s
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'pending')",
+				Booking::POST_TYPE,
+				$today
+			)
+		);
+	}
+
+	/**
+	 * Count today's check-outs.
+	 *
+	 * @return int
+	 */
+	private static function count_todays_checkouts(): int {
+		global $wpdb;
+		$today = gmdate( 'Y-m-d' );
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_date ON p.ID = pm_date.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_date.meta_key = '_bnb_booking_check_out'
+				AND pm_date.meta_value = %s
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value = 'checked_in'",
+				Booking::POST_TYPE,
+				$today
+			)
+		);
+	}
+
+	/**
+	 * Count upcoming bookings within given days.
+	 *
+	 * @param int $days Number of days to look ahead.
+	 * @return int
+	 */
+	private static function count_upcoming_bookings( int $days ): int {
+		global $wpdb;
+		$today   = gmdate( 'Y-m-d' );
+		$end_date = gmdate( 'Y-m-d', strtotime( "+{$days} days" ) );
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_date ON p.ID = pm_date.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_date.meta_key = '_bnb_booking_check_in'
+				AND pm_date.meta_value >= %s
+				AND pm_date.meta_value <= %s
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'pending')",
+				Booking::POST_TYPE,
+				$today,
+				$end_date
+			)
+		);
+	}
+
+	/**
+	 * Get average booking duration in nights.
+	 *
+	 * @return float
+	 */
+	private static function get_average_booking_duration(): float {
+		global $wpdb;
+
+		$result = $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT AVG(DATEDIFF(pm_out.meta_value, pm_in.meta_value))
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_in ON p.ID = pm_in.post_id
+				INNER JOIN {$wpdb->postmeta} pm_out ON p.ID = pm_out.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_in.meta_key = '_bnb_booking_check_in'
+				AND pm_out.meta_key = '_bnb_booking_check_out'
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value NOT IN ('cancelled')",
+				Booking::POST_TYPE
+			)
+		);
+
+		return round( (float) $result, 1 );
+	}
+
+	// =========================================================================
+	// Helper Methods - Guests
+	// =========================================================================
+
+	/**
+	 * Count guests by status.
+	 *
+	 * @param string $status Guest status.
+	 * @return int
+	 */
+	private static function count_guests_by_status( string $status ): int {
+		global $wpdb;
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm ON p.ID = pm.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm.meta_key = '_bnb_guest_status'
+				AND pm.meta_value = %s",
+				Guest::POST_TYPE,
+				$status
+			)
+		);
+	}
+
+	/**
+	 * Count repeat guests (more than one booking).
+	 *
+	 * @return int
+	 */
+	private static function count_repeat_guests(): int {
+		global $wpdb;
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT pm.meta_value)
+				FROM {$wpdb->postmeta} pm
+				INNER JOIN {$wpdb->posts} p ON pm.post_id = p.ID
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm.meta_key = '_bnb_booking_guest_id'
+				AND pm.meta_value != ''
+				GROUP BY pm.meta_value
+				HAVING COUNT(*) > 1",
+				Booking::POST_TYPE
+			)
+		);
+	}
+
+	/**
+	 * Count new guests registered this month.
+	 *
+	 * @return int
+	 */
+	private static function count_new_guests_this_month(): int {
+		global $wpdb;
+		$first_of_month = gmdate( 'Y-m-01 00:00:00' );
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(*)
+				FROM {$wpdb->posts}
+				WHERE post_type = %s
+				AND post_status = 'publish'
+				AND post_date >= %s",
+				Guest::POST_TYPE,
+				$first_of_month
+			)
+		);
+	}
+
+	// =========================================================================
+	// Helper Methods - Occupancy
+	// =========================================================================
+
+	/**
+	 * Get current occupancy rate (percentage of rooms occupied today).
+	 *
+	 * @return float
+	 */
+	private static function get_current_occupancy_rate(): float {
+		$total_rooms = self::count_available_rooms();
+		if ( $total_rooms <= 0 ) {
+			return 0.0;
+		}
+
+		$occupied = self::count_currently_occupied_rooms();
+		return round( ( $occupied / $total_rooms ) * 100, 1 );
+	}
+
+	/**
+	 * Get monthly occupancy rate.
+	 *
+	 * @return float
+	 */
+	private static function get_monthly_occupancy_rate(): float {
+		global $wpdb;
+
+		$total_rooms = self::count_available_rooms();
+		if ( $total_rooms <= 0 ) {
+			return 0.0;
+		}
+
+		$first_of_month = gmdate( 'Y-m-01' );
+		$today          = gmdate( 'Y-m-d' );
+		$days_so_far    = (int) gmdate( 'd' );
+		$total_room_nights = $total_rooms * $days_so_far;
+
+		// Count booked nights this month (simplified: count bookings that overlap with this month).
+		$booked_nights = (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT SUM(
+					DATEDIFF(
+						LEAST(pm_out.meta_value, %s),
+						GREATEST(pm_in.meta_value, %s)
+					)
+				)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_in ON p.ID = pm_in.post_id
+				INNER JOIN {$wpdb->postmeta} pm_out ON p.ID = pm_out.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_in.meta_key = '_bnb_booking_check_in'
+				AND pm_out.meta_key = '_bnb_booking_check_out'
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'checked_in', 'checked_out')
+				AND pm_in.meta_value <= %s
+				AND pm_out.meta_value >= %s",
+				$today,
+				$first_of_month,
+				Booking::POST_TYPE,
+				$today,
+				$first_of_month
+			)
+		);
+
+		if ( $total_room_nights <= 0 ) {
+			return 0.0;
+		}
+
+		return round( ( $booked_nights / $total_room_nights ) * 100, 1 );
+	}
+
+	/**
+	 * Count currently occupied rooms.
+	 *
+	 * @return int
+	 */
+	private static function count_currently_occupied_rooms(): int {
+		global $wpdb;
+		$today = gmdate( 'Y-m-d' );
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT pm_room.meta_value)
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_room ON p.ID = pm_room.post_id
+				INNER JOIN {$wpdb->postmeta} pm_in ON p.ID = pm_in.post_id
+				INNER JOIN {$wpdb->postmeta} pm_out ON p.ID = pm_out.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_room.meta_key = '_bnb_booking_room_id'
+				AND pm_in.meta_key = '_bnb_booking_check_in'
+				AND pm_out.meta_key = '_bnb_booking_check_out'
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'checked_in')
+				AND pm_in.meta_value <= %s
+				AND pm_out.meta_value > %s",
+				Booking::POST_TYPE,
+				$today,
+				$today
+			)
+		);
+	}
+
+	/**
+	 * Count available rooms (not in maintenance/inactive).
+	 *
+	 * @return int
+	 */
+	private static function count_available_rooms(): int {
+		global $wpdb;
+
+		return (int) $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT COUNT(DISTINCT p.ID)
+				FROM {$wpdb->posts} p
+				LEFT JOIN {$wpdb->postmeta} pm ON p.ID = pm.post_id AND pm.meta_key = '_bnb_room_status'
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND (pm.meta_value IS NULL OR pm.meta_value IN ('available', 'occupied'))",
+				Room::POST_TYPE
+			)
+		);
+	}
+
+	/**
+	 * Get total bed capacity.
+	 *
+	 * @return int
+	 */
+	private static function get_total_bed_capacity(): int {
+		global $wpdb;
+
+		$result = $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT SUM(CAST(pm.meta_value AS UNSIGNED))
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm ON p.ID = pm.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm.meta_key = '_bnb_room_beds'",
+				Room::POST_TYPE
+			)
+		);
+
+		return (int) $result;
+	}
+
+	// =========================================================================
+	// Helper Methods - Revenue
+	// =========================================================================
+
+	/**
+	 * Get revenue for the current month.
+	 *
+	 * @return float
+	 */
+	private static function get_revenue_this_month(): float {
+		global $wpdb;
+		$first_of_month = gmdate( 'Y-m-01' );
+
+		$result = $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT SUM(CAST(pm_price.meta_value AS DECIMAL(10,2)))
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_price ON p.ID = pm_price.post_id
+				INNER JOIN {$wpdb->postmeta} pm_in ON p.ID = pm_in.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_price.meta_key = '_bnb_booking_total_price'
+				AND pm_in.meta_key = '_bnb_booking_check_in'
+				AND pm_in.meta_value >= %s
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'checked_in', 'checked_out')",
+				Booking::POST_TYPE,
+				$first_of_month
+			)
+		);
+
+		return round( (float) $result, 2 );
+	}
+
+	/**
+	 * Get revenue year to date.
+	 *
+	 * @return float
+	 */
+	private static function get_revenue_ytd(): float {
+		global $wpdb;
+		$first_of_year = gmdate( 'Y-01-01' );
+
+		$result = $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT SUM(CAST(pm_price.meta_value AS DECIMAL(10,2)))
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_price ON p.ID = pm_price.post_id
+				INNER JOIN {$wpdb->postmeta} pm_in ON p.ID = pm_in.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_price.meta_key = '_bnb_booking_total_price'
+				AND pm_in.meta_key = '_bnb_booking_check_in'
+				AND pm_in.meta_value >= %s
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'checked_in', 'checked_out')",
+				Booking::POST_TYPE,
+				$first_of_year
+			)
+		);
+
+		return round( (float) $result, 2 );
+	}
+
+	/**
+	 * Get average booking value.
+	 *
+	 * @return float
+	 */
+	private static function get_average_booking_value(): float {
+		global $wpdb;
+
+		$result = $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT AVG(CAST(pm_price.meta_value AS DECIMAL(10,2)))
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_price ON p.ID = pm_price.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_price.meta_key = '_bnb_booking_total_price'
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'checked_in', 'checked_out')",
+				Booking::POST_TYPE
+			)
+		);
+
+		return round( (float) $result, 2 );
+	}
+
+	/**
+	 * Get revenue from services this month.
+	 *
+	 * @return float
+	 */
+	private static function get_services_revenue_this_month(): float {
+		global $wpdb;
+		$first_of_month = gmdate( 'Y-m-01' );
+
+		$result = $wpdb->get_var(
+			$wpdb->prepare(
+				"SELECT SUM(CAST(pm_services.meta_value AS DECIMAL(10,2)))
+				FROM {$wpdb->posts} p
+				INNER JOIN {$wpdb->postmeta} pm_services ON p.ID = pm_services.post_id
+				INNER JOIN {$wpdb->postmeta} pm_in ON p.ID = pm_in.post_id
+				INNER JOIN {$wpdb->postmeta} pm_status ON p.ID = pm_status.post_id
+				WHERE p.post_type = %s
+				AND p.post_status = 'publish'
+				AND pm_services.meta_key = '_bnb_booking_services_total'
+				AND pm_in.meta_key = '_bnb_booking_check_in'
+				AND pm_in.meta_value >= %s
+				AND pm_status.meta_key = '_bnb_booking_status'
+				AND pm_status.meta_value IN ('confirmed', 'checked_in', 'checked_out')",
+				Booking::POST_TYPE,
+				$first_of_month
+			)
+		);
+
+		return round( (float) $result, 2 );
+	}
+}

src/Plugin.php

@@ -19,6 +19,7 @@ use Magdev\WpBnb\Booking\EmailNotifier;
 use Magdev\WpBnb\Frontend\Search;
 use Magdev\WpBnb\Frontend\Shortcodes;
 use Magdev\WpBnb\Integration\CF7;
+use Magdev\WpBnb\Integration\Prometheus;
 use Magdev\WpBnb\Frontend\Widgets\AvailabilityCalendar;
 use Magdev\WpBnb\Frontend\Widgets\BuildingRooms;
 use Magdev\WpBnb\Frontend\Widgets\SimilarRooms;
@@ -142,6 +143,9 @@ final class Plugin {
 			CF7::init();
 		}
 
+		// Initialize Prometheus metrics integration.
+		Prometheus::init();
+
 		// Initialize admin components.
 		if ( is_admin() ) {
 			$this->init_admin();
@@ -610,6 +614,10 @@ final class Plugin {
 				   class="nav-tab <?php echo 'updates' === $active_tab ? 'nav-tab-active' : ''; ?>">
 					<?php esc_html_e( 'Updates', 'wp-bnb' ); ?>
 				</a>
+				<a href="<?php echo esc_url( admin_url( 'admin.php?page=wp-bnb-settings&tab=metrics' ) ); ?>"
+				   class="nav-tab <?php echo 'metrics' === $active_tab ? 'nav-tab-active' : ''; ?>">
+					<?php esc_html_e( 'Metrics', 'wp-bnb' ); ?>
+				</a>
 			</nav>
 
 			<div class="tab-content">
@@ -624,6 +632,9 @@ final class Plugin {
 					case 'updates':
 						$this->render_updates_settings();
 						break;
+					case 'metrics':
+						$this->render_metrics_settings();
+						break;
 					default:
 						$this->render_general_settings();
 						break;
@@ -1265,6 +1276,163 @@ final class Plugin {
 		<?php
 	}
 
+	/**
+	 * Render metrics settings tab.
+	 *
+	 * @return void
+	 */
+	private function render_metrics_settings(): void {
+		$metrics_enabled     = Prometheus::is_enabled();
+		$prometheus_active   = class_exists( '\Magdev\WpPrometheus\Plugin' ) || defined( 'WP_PROMETHEUS_VERSION' );
+		$dashboard_file      = WP_BNB_PATH . 'assets/grafana/wp-bnb-dashboard.json';
+		$dashboard_available = file_exists( $dashboard_file );
+		?>
+		<form method="post" action="">
+			<?php wp_nonce_field( 'wp_bnb_save_settings', 'wp_bnb_settings_nonce' ); ?>
+
+			<h2><?php esc_html_e( 'Prometheus Metrics', 'wp-bnb' ); ?></h2>
+
+			<?php if ( ! $prometheus_active ) : ?>
+				<div class="notice notice-warning inline" style="margin: 0 0 20px 0;">
+					<p>
+						<span class="dashicons dashicons-warning" style="color: #dba617;"></span>
+						<strong><?php esc_html_e( 'WP Prometheus not detected', 'wp-bnb' ); ?></strong><br>
+						<?php
+						printf(
+							/* translators: %s: Plugin URL */
+							esc_html__( 'The WP Prometheus plugin is required to expose metrics. Please install and activate it from %s.', 'wp-bnb' ),
+							'<a href="https://src.bundespruefstelle.ch/magdev/wp-prometheus" target="_blank">wp-prometheus</a>'
+						);
+						?>
+					</p>
+				</div>
+			<?php else : ?>
+				<div class="notice notice-success inline" style="margin: 0 0 20px 0;">
+					<p>
+						<span class="dashicons dashicons-yes-alt" style="color: #00a32a;"></span>
+						<strong><?php esc_html_e( 'WP Prometheus is active', 'wp-bnb' ); ?></strong>
+						<?php esc_html_e( 'Metrics will be exposed via the /metrics/ endpoint.', 'wp-bnb' ); ?>
+					</p>
+				</div>
+			<?php endif; ?>
+
+			<table class="form-table" role="presentation">
+				<tr>
+					<th scope="row"><?php esc_html_e( 'Enable Metrics', 'wp-bnb' ); ?></th>
+					<td>
+						<label>
+							<input type="checkbox" name="wp_bnb_metrics_enabled"
+								   value="yes" <?php checked( $metrics_enabled ); ?>>
+							<?php esc_html_e( 'Expose BnB metrics via Prometheus', 'wp-bnb' ); ?>
+						</label>
+						<p class="description">
+							<?php esc_html_e( 'When enabled, occupancy, booking, revenue, and guest metrics will be available for Prometheus scraping.', 'wp-bnb' ); ?>
+						</p>
+					</td>
+				</tr>
+			</table>
+
+			<h2><?php esc_html_e( 'Available Metrics', 'wp-bnb' ); ?></h2>
+			<p class="description"><?php esc_html_e( 'The following metrics are exposed when enabled:', 'wp-bnb' ); ?></p>
+
+			<table class="widefat striped" style="max-width: 800px; margin-top: 10px;">
+				<thead>
+					<tr>
+						<th><?php esc_html_e( 'Metric', 'wp-bnb' ); ?></th>
+						<th><?php esc_html_e( 'Type', 'wp-bnb' ); ?></th>
+						<th><?php esc_html_e( 'Description', 'wp-bnb' ); ?></th>
+					</tr>
+				</thead>
+				<tbody>
+					<tr>
+						<td><code>wp_bnb_buildings_total</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Total number of buildings', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_rooms_total</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Total rooms by status (available, occupied, maintenance, inactive)', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_bookings_total</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Total bookings by status (pending, confirmed, checked_in, checked_out, cancelled)', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_occupancy_rate_current</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Current room occupancy rate (percentage)', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_occupancy_rate_this_month</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Room occupancy rate for current month (percentage)', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_checkins_today</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Number of check-ins scheduled for today', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_checkouts_today</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Number of check-outs scheduled for today', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_revenue_this_month</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Total revenue for current month', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_revenue_ytd</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Total revenue year to date', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_booking_avg_value</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Average booking value', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_guests_total</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Total number of registered guests', 'wp-bnb' ); ?></td>
+					</tr>
+					<tr>
+						<td><code>wp_bnb_guests_repeat</code></td>
+						<td><?php esc_html_e( 'Gauge', 'wp-bnb' ); ?></td>
+						<td><?php esc_html_e( 'Number of repeat guests (more than one booking)', 'wp-bnb' ); ?></td>
+					</tr>
+				</tbody>
+			</table>
+
+			<h2 style="margin-top: 30px;"><?php esc_html_e( 'Grafana Dashboard', 'wp-bnb' ); ?></h2>
+
+			<?php if ( $dashboard_available ) : ?>
+				<p>
+					<?php esc_html_e( 'A pre-configured Grafana dashboard is available for visualizing WP BnB metrics.', 'wp-bnb' ); ?>
+				</p>
+				<p>
+					<strong><?php esc_html_e( 'Dashboard file:', 'wp-bnb' ); ?></strong>
+					<code>assets/grafana/wp-bnb-dashboard.json</code>
+				</p>
+				<p class="description">
+					<?php esc_html_e( 'If WP Prometheus is installed, this dashboard will be automatically registered and available for export in the Prometheus settings.', 'wp-bnb' ); ?>
+				</p>
+			<?php else : ?>
+				<div class="notice notice-warning inline">
+					<p><?php esc_html_e( 'Grafana dashboard file not found.', 'wp-bnb' ); ?></p>
+				</div>
+			<?php endif; ?>
+
+			<p class="submit">
+				<?php submit_button( __( 'Save Metrics Settings', 'wp-bnb' ), 'primary', 'submit', false ); ?>
+			</p>
+		</form>
+		<?php
+	}
+
 	/**
 	 * Render license status badge.
 	 *
@@ -1336,6 +1504,9 @@ final class Plugin {
 			case 'updates':
 				$this->save_updates_settings();
 				break;
+			case 'metrics':
+				$this->save_metrics_settings();
+				break;
 			default:
 				$this->save_general_settings();
 				break;
@@ -1465,6 +1636,19 @@ final class Plugin {
 		settings_errors( 'wp_bnb_settings' );
 	}
 
+	/**
+	 * Save metrics settings.
+	 *
+	 * @return void
+	 */
+	private function save_metrics_settings(): void {
+		$metrics_enabled = isset( $_POST['wp_bnb_metrics_enabled'] ) ? 'yes' : 'no';
+		update_option( Prometheus::OPTION_ENABLED, $metrics_enabled );
+
+		add_settings_error( 'wp_bnb_settings', 'settings_saved', __( 'Metrics settings saved.', 'wp-bnb' ), 'success' );
+		settings_errors( 'wp_bnb_settings' );
+	}
+
 	/**
 	 * AJAX handler for checking room availability.
 	 *