<?php
/**
 * Favorites adapter — `hivepress-favorites`.
 *
 * The Favorite model extends Comment (`comment_type = hp_favorite`):
 *
 *   - user      → user_id
 *   - listing   → comment_post_ID
 *   - added_at  → comment_date
 *
 * Problem: `wp_comments` has no UNIQUE constraint on (user_id, comment_post_ID, comment_type).
 * A double-tap on the favourite button can race and create two duplicate
 * favourite rows. HivePress relies on application-level dedup (SELECT before
 * INSERT) which is not race-safe.
 *
 * Fix: shadow table `wp_wpdo_comment_hp_favorite` with UNIQUE(user_id, listing_id).
 * Adapter mirrors every favorite write into the shadow table; the comment
 * router rewrites "is X favorited by user Y" reads to hit the shadow table
 * (1 indexed lookup vs WP_Comment_Query meta scan).
 *
 * Schema (declared via expected_columns; created by TMDO_Schema_Manager
 * when adapter mode flips to dual_write):
 *
 *   CREATE TABLE wp_wpdo_comment_hp_favorite (
 *       comment_id BIGINT UNSIGNED NOT NULL PRIMARY KEY,
 *       user_id    BIGINT UNSIGNED NOT NULL,
 *       listing_id BIGINT UNSIGNED NOT NULL,
 *       created_at DATETIME       NOT NULL,
 *       UNIQUE KEY unique_user_listing (user_id, listing_id),
 *       KEY idx_listing (listing_id)
 *   );
 *
 * @package WP_Data_Optimizer
 * @since   3.0.0
 */

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

if ( ! class_exists( 'TMDO_HivePress_Favorites_Adapter' ) ) {

	/**
	 * Favorites addon adapter.
	 */
	final class TMDO_HivePress_Favorites_Adapter implements TMDO_HivePress_Adapter {

		use TMDO_HivePress_Adapter_Trait;

		/** Comment_type owned by this adapter. */
		public const COMMENT_TYPE = 'hp_favorite';

		/** Shadow table name (without wpdb prefix). */
		public const TABLE = 'wpdo_comment_hp_favorite';

		/**
		 * Constructor — bind register hooks via inherited trait.
		 */
		public function __construct() {
			$this->bind_anti_eav_hooks();
		}

		/** Adapter slug (matches wp.org plugin slug). */
		public function plugin_slug(): string {
			return 'hivepress-favorites';
		}

		/** Class probed for addon presence. */
		public function detection_class(): string {
			return 'HivePress\\Favorites\\Plugin';
		}

		/** Version constant probed for addon presence. */
		public function detection_const(): string {
			return 'HIVEPRESS_FAVORITES_VERSION';
		}

		/** Minimum addon version supported. */
		public function minimum_addon_version(): string {
			return '1.2.0';
		}

		/**
		 * Declare the shadow table to the Custom_Table_Registry.
		 *
		 * @param TMDO_Custom_Table_Registry $registry Registry singleton.
		 */
		public function on_register_custom_tables( TMDO_Custom_Table_Registry $registry ): void {
			$this->register_custom_table(
				$registry,
				array(
					'table_name'       => self::TABLE,
					'primary_key'      => 'comment_id',
					'post_type_link'   => null,
					'expected_columns' => array(
						'comment_id' => 'BIGINT UNSIGNED NOT NULL PRIMARY KEY',
						'user_id'    => 'BIGINT UNSIGNED NOT NULL',
						'listing_id' => 'BIGINT UNSIGNED NOT NULL',
						'created_at' => 'DATETIME NOT NULL',
					),
					'indexes'          => array(
						'unique_user_listing' => 'UNIQUE (user_id, listing_id)',
						'idx_listing'         => '(listing_id)',
					),
					'doctor_callback'  => array( $this, 'doctor_check' ),
				)
			);
		}

		/**
		 * Sync wp_comments → shadow table on insert.
		 *
		 * Bound during `on_register_event_hooks()`. The comment-router uses
		 * the shadow table for "is favorited" lookups; sync keeps it consistent.
		 */
		public function on_register_event_hooks(): void {
			add_action( 'wp_insert_comment', array( $this, 'mirror_insert' ), 10, 2 );
			add_action( 'deleted_comment', array( $this, 'mirror_delete' ), 10, 2 );
		}

		/**
		 * Mirror a newly-inserted hp_favorite into the shadow table.
		 *
		 * @param int                $comment_id Comment ID.
		 * @param object|\WP_Comment $comment Comment object.
		 */
		public function mirror_insert( int $comment_id, $comment ): void {
			if ( ! is_object( $comment ) || ( $comment->comment_type ?? '' ) !== self::COMMENT_TYPE ) {
				return;
			}
			global $wpdb;
			$user_id    = (int) ( $comment->user_id ?? 0 );
			$listing_id = (int) ( $comment->comment_post_ID ?? 0 );
			if ( $user_id <= 0 || $listing_id <= 0 ) {
				return;
			}
			$wpdb->query( // phpcs:ignore WordPress.DB.DirectDatabaseQuery, WordPress.DB.PreparedSQL.InterpolatedNotPrepared
				$wpdb->prepare(
					'INSERT IGNORE INTO `' . $wpdb->prefix . self::TABLE . '` (comment_id, user_id, listing_id, created_at) VALUES (%d, %d, %d, %s)',
					$comment_id,
					$user_id,
					$listing_id,
					$comment->comment_date ?? current_time( 'mysql' )
				)
			);
		}

		/**
		 * Remove the shadow row when a hp_favorite comment is deleted.
		 *
		 * @param int                $comment_id Comment ID.
		 * @param object|\WP_Comment $comment Comment object.
		 */
		public function mirror_delete( int $comment_id, $comment ): void {
			if ( ! is_object( $comment ) || ( $comment->comment_type ?? '' ) !== self::COMMENT_TYPE ) {
				return;
			}
			global $wpdb;
			$wpdb->delete( // phpcs:ignore WordPress.DB.DirectDatabaseQuery
				$wpdb->prefix . self::TABLE,
				array( 'comment_id' => $comment_id ),
				array( '%d' )
			);
		}

		/**
		 * Doctor probe — verify shadow table exists.
		 *
		 * @return array{ok:bool, message:string, details?:array<string,mixed>}
		 */
		public function doctor_check(): array {
			global $wpdb;
			if ( ! isset( $wpdb ) || ! is_object( $wpdb ) ) {
				return array(
					'ok'      => false,
					'message' => 'wpdb global not available',
				);
			}
			$table = $wpdb->prefix . self::TABLE;
			try {
				$exists = (bool) $wpdb->get_var(
					$wpdb->prepare( 'SHOW TABLES LIKE %s', $table )
				);
				if ( ! $exists ) {
					return array(
						'ok'      => false,
						'message' => sprintf( 'hivepress-favorites: shadow table %s missing', $table ),
						'details' => array( 'table' => $table ),
					);
				}
				$rows = (int) $wpdb->get_var( "SELECT COUNT(*) FROM `{$table}`" ); // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
				return array(
					'ok'      => true,
					'message' => sprintf( 'hivepress-favorites: %s rows=%d', $table, $rows ),
					'details' => array(
						'table' => $table,
						'rows'  => $rows,
					),
				);
			} catch ( \Throwable $e ) {
				return array(
					'ok'      => false,
					'message' => sprintf( 'hivepress-favorites doctor failed: %s', $e->getMessage() ),
				);
			}
		}

		/**
		 * 8-D self-score.
		 *
		 *  D1: 1.0 — adapter never calls *_meta()
		 *  D2: 1.0 — uses wpdb prefix, no hardcoded table literals
		 *  D3: 1.0 — shadow table covers the model
		 *  D4: 1.0 — expected_columns + indexes registered
		 *  D5: 1.0 — listens to wp_insert_comment for cross-write consistency
		 *  D6: 1.0 — zero options/transients
		 *  D7: 1.0 — only queries own shadow table
		 *  D8: 1.0 — UNIQUE(user_id, listing_id) covering index
		 */
		public function suitability_score(): array {
			return $this->compose_score( array() );
		}

		/**
		 * FSM modules this adapter contributes.
		 *
		 * @return array<int,string>
		 */
		public function migrations(): array {
			return array( 'comment_hp_favorite' );
		}
	}

} // end if ( ! class_exists )