<?php
/**
 * TMDO_Hook_Bus - 統一 Hook 攔截匯流排
 *
 * 所有 WordPress 的 meta 操作皆通過此匯流排：
 * - {type}_metadata 系列 filter（add/get/update/delete）
 * - 實體刪除 action
 * - 原生查詢擴充 hook
 *
 * @package WP_Data_Optimizer
 */

// phpcs:disable Squiz.Commenting,Generic.Commenting,WordPress.DB.PreparedSQL.NotPrepared,WordPress.DB.PreparedSQL.InterpolatedNotPrepared,WordPress.DB.PreparedSQLPlaceholders.ReplacementsWrongNumber,Generic.CodeAnalysis.UnusedFunctionParameter,Generic.CodeAnalysis.EmptyStatement,Squiz.PHP.DisallowMultipleAssignments,Squiz.PHP.DisallowSizeFunctionsInLoops,WordPress.WP.I18n.MissingTranslatorsComment,WordPress.PHP.NoSilencedErrors,WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents,Squiz.PHP.CommentedOutCode,Universal.NamingConventions.NoReservedKeywordParameterNames,WordPress.PHP.YodaConditions,Squiz.Commenting.InlineComment.InvalidEndChar -- PR-1 ported from UAE; cleanup PR scheduled.


defined( 'ABSPATH' ) || exit;

final class TMDO_Hook_Bus {

	/** 標記：防止在內部 UPSERT 時遞迴觸發 filter */
	private static array $internal_ops = array();

	public static function init(): void {

		// 取得所有已註冊的適配器
		$adapters = TMDO_Entity_Registry::get_all_adapters();

		foreach ( $adapters as $type => $adapter ) {
			self::register_hooks_for_type( $type, $adapter );
		}
	}

	private static function register_hooks_for_type( string $type, TMDO_Entity_Adapter_Interface $adapter ): void {

		// ── 寫入攔截 ──────────────────────────────────────────
		add_filter( "update_{$type}_metadata", array( self::class, 'intercept_update' ), 10, 5 );
		add_filter( "add_{$type}_metadata", array( self::class, 'intercept_add' ), 10, 5 );

		// ── 讀取攔截 ──────────────────────────────────────────
		add_filter( "get_{$type}_metadata", array( self::class, 'intercept_get' ), 10, 5 );

		// ── 刪除攔截 ──────────────────────────────────────────
		add_filter( "delete_{$type}_metadata", array( self::class, 'intercept_delete' ), 10, 5 );

		// ── 實體刪除時自動清理 ───────────────────────────────
		add_action(
			$adapter->get_delete_hook(),
			function ( $entity_id ) use ( $type, $adapter ) {
				self::cleanup_entity( $type, (int) $entity_id );
			},
			10,
			1
		);
	}

	// ─────────────────────────────────────────────────────────
	// 寫入：update_{type}_metadata filter
	// ─────────────────────────────────────────────────────────

	/**
	 * 短路 WordPress 原生 update_metadata() 流程
	 *
	 * @param null|bool $check       若回傳 null 則 WP 繼續原生流程
	 * @param int       $object_id
	 * @param string    $meta_key
	 * @param mixed     $meta_value
	 * @param mixed     $prev_value
	 */
	public static function intercept_update( $check, $object_id, $meta_key, $meta_value, $prev_value ) {

		// 已在短路中 → 避免遞迴
		if ( ! empty( self::$internal_ops[ $object_id . ':' . $meta_key ] ) ) {
			return $check;
		}

		$type = self::resolve_type_from_current_filter();
		if ( ! $type ) {
			return $check;
		}

		$field_def = TMDO_Entity_Registry::get_field( $type, $meta_key );
		if ( ! $field_def ) {
			return $check; // 非管理欄位，放行
		}

		// ── Mode-aware dispatch ──────────────────────────────
		// disabled  : 完全放行給 WP 原生 meta(回 null / $check)
		// dual_write: 寫 flat,然後 return null 讓 WP 繼續寫 EAV
		// shadow_read: 寫 flat,然後 return null 讓 WP 繼續寫 EAV
		// aeav_only : 寫 flat,return true 短路 WP(不寫 EAV)
		if ( ! TMDO_Mode_Manager::writes_to_flat( $type ) ) {
			return $check;  // disabled
		}

		// Route decision (v1.2.0):讓 UAEPG 等外掛正式訂閱 routing,不必搶 priority 5。
		$route = self::decide_route( 'update', $type, (int) $object_id, $meta_key, $meta_value );
		if ( $route === 'pg' ) {
			// 讓其他 listener(例如 UAEPG)接手;原生 EAV 也放行。
			return null;
		}
		if ( $route === 'skip' ) {
			// 不寫 flat、不寫 EAV,但告訴 WP 已處理。
			return true;
		}

		// 截取 before value(v1.3.1):audit_logger 等訂閱者需要變更前的值。
		// v1.3.2:透過 filter `wpdo_capture_before_value` 可關閉以省一次 DB read。
		$before_value = self::maybe_read_before_value( $type, (int) $object_id, $meta_key, $field_def, 'update' );

		$flat_result = self::perform_upsert( $type, (int) $object_id, $meta_key, $meta_value, $field_def );

		do_action( 'wpdo_after_write', $type, (int) $object_id, $meta_key, $meta_value, $flat_result, 'update', $before_value );

		// 若 mode 也要寫 EAV → return null 讓 WP 繼續
		if ( TMDO_Mode_Manager::writes_to_eav( $type ) ) {
			return null;  // dual_write / shadow_read
		}

		return $flat_result;  // aeav_only
	}

	public static function intercept_add( $check, $object_id, $meta_key, $meta_value, $unique ) {

		// 已在短路中 → 避免遞迴
		if ( ! empty( self::$internal_ops[ $object_id . ':' . $meta_key ] ) ) {
			return $check;
		}

		$type = self::resolve_type_from_current_filter();
		if ( ! $type ) {
			return $check;
		}

		$field_def = TMDO_Entity_Registry::get_field( $type, $meta_key );
		if ( ! $field_def ) {
			return $check;
		}

		if ( ! TMDO_Mode_Manager::writes_to_flat( $type ) ) {
			return $check;
		}

		$route = self::decide_route( 'add', $type, (int) $object_id, $meta_key, $meta_value );
		if ( $route === 'pg' ) {
			return null;
		}
		if ( $route === 'skip' ) {
			return true;
		}

		// UAE 的設計:每個 entity 只有 1 row,所以 add 與 update 等效(Upsert)。
		// 截取 before value(v1.3.1):add 情境下多半為 null,但若 row 已存在而 user 呼叫 add 也能抓到舊值。
		$before_value = self::maybe_read_before_value( $type, (int) $object_id, $meta_key, $field_def, 'add' );

		$flat_result = self::perform_upsert( $type, (int) $object_id, $meta_key, $meta_value, $field_def );

		do_action( 'wpdo_after_write', $type, (int) $object_id, $meta_key, $meta_value, $flat_result, 'add', $before_value );

		if ( TMDO_Mode_Manager::writes_to_eav( $type ) ) {
			return null;
		}

		return $flat_result;
	}

	/**
	 * 如 filter `wpdo_capture_before_value` 回 true 才讀 flat table 的 before value,
	 * 否則直接回 null — 讓沒在用 audit / 其他 listener 的站台省一次 DB read。
	 *
	 * filter 參數:(bool $default_true, string $type, string $meta_key, string $op)
	 *   $op ∈ { 'add', 'update', 'delete' }
	 *
	 * 使用範例(關閉 audit 的站台):
	 *   add_filter( 'wpdo_capture_before_value', '__return_false' );
	 *
	 * @since 1.3.2
	 */
	private static function maybe_read_before_value(
		string $type,
		int $entity_id,
		string $meta_key,
		array $field_def,
		string $op
	) {
		// Default false since v3.1.5 (A): reading the previous flat value costs an
		// extra DB read on every managed write. Sites that consume value_before —
		// e.g. the audit log — must opt in:
		//   add_filter( 'wpdo_capture_before_value', '__return_true' );
		$capture = apply_filters(
			'wpdo_capture_before_value',
			false,
			$type,
			$meta_key,
			$op
		);

		if ( ! $capture ) {
			return null;
		}

		return self::read_flat_value( $type, $entity_id, $meta_key, $field_def );
	}

	/**
	 * 讀取 flat table 中當前值(before value,供 audit / after_write listener 使用)。
	 *
	 * 此方法**不經 cache 加熱**,直接查 DB,以避免快取污染與遞迴。表不存在回 null。
	 *
	 * @since 1.3.1
	 */
	private static function read_flat_value(
		string $type,
		int $entity_id,
		string $meta_key,
		array $field_def
	) {
		global $wpdb;

		$adapter = TMDO_Entity_Registry::get_adapter( $type );
		if ( ! $adapter ) {
			return null;
		}

		$group = $field_def['group'] ?? '';
		if ( $group === '' ) {
			return null;
		}

		$table = TMDO_Schema_Manager::get_table_name( $type, $group );
		if ( ! TMDO_Schema_Manager::table_exists( $table ) ) {
			return null;
		}

		$col    = TMDO_Schema_Manager::sanitize_column_name( $meta_key );
		$id_col = $adapter->get_entity_id_column();

		$raw = $wpdb->get_var(
			$wpdb->prepare(
				"SELECT `{$col}` FROM `{$table}` WHERE `{$id_col}` = %d LIMIT 1",
				$entity_id
			)
		);

		return $raw === null ? null : TMDO_Type_Caster::from_db( $raw, $field_def );
	}

	/**
	 * 讓外部 listener(例如 UAEPG)透過 `wpdo_route_decision` filter 指定路由。
	 *
	 * 回傳值:
	 *   'flat' (預設) — UAE 寫入 MySQL flat table
	 *   'pg'          — 放行,由其他 listener 接手;UAE 不寫 flat,原生 EAV 依 mode 決定
	 *   'skip'        — 都不寫(用於軟刪除之類特殊情境),但告訴 WP 已處理
	 *
	 * 其他非預期值會被 fallback 到 'flat' 以維持安全預設。
	 *
	 * @since 1.2.0
	 */
	private static function decide_route(
		string $op,
		string $type,
		int $object_id,
		string $meta_key,
		$meta_value
	): string {
		$route = apply_filters(
			'wpdo_route_decision',
			'flat',
			$type,
			$object_id,
			$meta_key,
			$meta_value,
			$op
		);

		if ( in_array( $route, array( 'flat', 'pg', 'skip' ), true ) ) {
			return $route;
		}

		TMDO_Logger::warning(
			'wpdo_route_decision_invalid_return',
			array(
				'returned' => is_scalar( $route ) ? (string) $route : gettype( $route ),
				'op'       => $op,
				'type'     => $type,
				'key'      => $meta_key,
			)
		);
		return 'flat';
	}

	/**
	 * 執行 Upsert 操作
	 */
	private static function perform_upsert(
		string $type,
		int $entity_id,
		string $meta_key,
		$meta_value,
		array $field_def
	) {
		global $wpdb;

		$adapter = TMDO_Entity_Registry::get_adapter( $type );
		if ( ! $adapter ) {
			return null;
		}

		$group  = $field_def['group'];
		$table  = TMDO_Schema_Manager::get_table_name( $type, $group );
		$id_col = $adapter->get_entity_id_column();
		$col    = TMDO_Schema_Manager::sanitize_column_name( $meta_key );

		// 表不存在則讓 WP 走原生流程（降級處理）
		if ( ! TMDO_Schema_Manager::table_exists( $table ) ) {
			return null;
		}

		// 型別轉換
		$db_value = TMDO_Type_Caster::to_db( $meta_value, $field_def );
		$format   = TMDO_Type_Caster::get_wpdb_format( $field_def['type'] );

		// 鎖防遞迴
		$lock_key                        = $entity_id . ':' . $meta_key;
		self::$internal_ops[ $lock_key ] = true;

		try {
			// 單一 upsert，避免 SELECT→UPDATE/INSERT 的 read-modify-write race。
			$result = TMDO_DB::upsert(
				$table,
				array(
					$id_col => $entity_id,
					$col    => $db_value,
				),
				array( $col ),
				$id_col,
				array( '%d', $format )
			);

			// 清除快取
			TMDO_Cache_Orchestrator::invalidate( $type, $entity_id, $group );

			// 短路回傳 true（WP 認為寫入成功）
			return $result !== false;
		} finally {
			unset( self::$internal_ops[ $lock_key ] );
		}
	}

	// ─────────────────────────────────────────────────────────
	// 讀取：get_{type}_metadata filter
	// ─────────────────────────────────────────────────────────

	/**
	 * 攔截 get_metadata() 呼叫
	 *
	 * @param null|mixed $check      若回傳 null 則 WP 繼續原生流程
	 * @param int        $object_id
	 * @param string     $meta_key   空字串表示取所有 meta
	 * @param bool       $single
	 * @param string     $meta_type  5.5+ 額外參數
	 */
	public static function intercept_get( $check, $object_id, $meta_key, $single, $meta_type = '' ) {

		$type = $meta_type ?: self::resolve_type_from_current_filter();
		if ( ! $type ) {
			return $check;
		}

		// 空 key：WP 要求所有 meta，UAE 不攔截（維持相容性）
		if ( $meta_key === '' ) {
			return $check;
		}

		$field_def = TMDO_Entity_Registry::get_field( $type, $meta_key );
		if ( ! $field_def ) {
			return $check;
		}

		// ── Mode-aware dispatch ──────────────────────────────
		// disabled    : 完全不攔截,回傳 $check 讓 WP 走原生 EAV
		// dual_write  : 讀取仍走 EAV(flat 可能還沒有資料),回傳 $check
		// shadow_read : 讀取走 UAE flat,同時與 EAV 比對記錄 diff
		// aeav_only   : 讀取走 UAE flat,不讀 EAV
		if ( ! TMDO_Mode_Manager::reads_from_flat( $type ) ) {
			return $check;  // disabled / dual_write
		}

		$group = $field_def['group'];
		$row   = self::get_or_load_row( $type, (int) $object_id, $group );

		$col       = TMDO_Schema_Manager::sanitize_column_name( $meta_key );
		$has_value = is_array( $row ) && array_key_exists( $col, $row );
		$value     = $has_value ? TMDO_Type_Caster::from_db( $row[ $col ], $field_def ) : null;

		// Shadow-read:與 EAV 比對,記錄差異
		if ( TMDO_Mode_Manager::does_shadow_compare( $type ) ) {
			try {
				TMDO_Shadow_Diff_Logger::compare_and_log(
					$type,
					(int) $object_id,
					$meta_key,
					$value,
					$field_def
				);
			} catch ( \Throwable $e ) {
				// 比對失敗不該影響讀取
				TMDO_Logger::error( 'entity_bridge', 'shadow_compare_exception', $e->getMessage() );
			}
		}

		// 值為空 → 回 WP 原生慣例
		if ( empty( $row ) || $value === null || $value === '' ) {
			return $single ? '' : array();
		}

		// WP 的慣例：get_metadata() 即使 $single=true 也回傳陣列包裝
		return $single ? array( $value ) : array( $value );
	}

	/**
	 * 取得（或載入）完整列資料，並快取
	 */
	private static function get_or_load_row( string $type, int $entity_id, string $group ): array {

		// L1 快取
		$cached = TMDO_Cache_Orchestrator::get_row( $type, $entity_id, $group );
		if ( is_array( $cached ) ) {
			return $cached;
		}

		global $wpdb;

		$adapter = TMDO_Entity_Registry::get_adapter( $type );
		if ( ! $adapter ) {
			return array();
		}

		$table  = TMDO_Schema_Manager::get_table_name( $type, $group );
		$id_col = $adapter->get_entity_id_column();

		if ( ! TMDO_Schema_Manager::table_exists( $table ) ) {
			return array();
		}

		$row = $wpdb->get_row(
			$wpdb->prepare(
				"SELECT * FROM `{$table}` WHERE `{$id_col}` = %d LIMIT 1",
				$entity_id
			),
			ARRAY_A
		);

		$row = $row ?: array();

		TMDO_Cache_Orchestrator::set_row( $type, $entity_id, $group, $row );

		return $row;
	}

	// ─────────────────────────────────────────────────────────
	// 刪除：delete_{type}_metadata filter
	// ─────────────────────────────────────────────────────────

	public static function intercept_delete( $check, $object_id, $meta_key, $meta_value, $delete_all ) {

		$type = self::resolve_type_from_current_filter();
		if ( ! $type ) {
			return $check;
		}

		$field_def = TMDO_Entity_Registry::get_field( $type, $meta_key );
		if ( ! $field_def ) {
			return $check;
		}

		// Mode-aware:disabled 完全不攔截
		if ( ! TMDO_Mode_Manager::writes_to_flat( $type ) ) {
			return $check;
		}

		$route = self::decide_route( 'delete', $type, (int) $object_id, $meta_key, $meta_value );
		if ( $route === 'pg' ) {
			return null;
		}
		if ( $route === 'skip' ) {
			return true;
		}

		// 截取 before value(v1.3.1)
		$before_value = self::maybe_read_before_value( $type, (int) $object_id, $meta_key, $field_def, 'delete' );

		global $wpdb;

		$adapter = TMDO_Entity_Registry::get_adapter( $type );
		$group   = $field_def['group'];
		$table   = TMDO_Schema_Manager::get_table_name( $type, $group );
		$id_col  = $adapter->get_entity_id_column();
		$col     = TMDO_Schema_Manager::sanitize_column_name( $meta_key );

		if ( ! TMDO_Schema_Manager::table_exists( $table ) ) {
			return $check;
		}

		// UAE 的邏輯：刪除 meta = 設該欄位為 NULL
		// 因為一個 entity 只對應一列，完整刪除列會丟失其他欄位
		$default = $field_def['default'] ?? null;

		if ( $delete_all ) {
			/**
			 * Opt-in gate for mass column clear (delete_all=true).
			 *
			 * Defaults to false — a single mistargetted call NULLs the column for
			 * every entity, and the previous row-count heuristic let small sites
			 * (< 500 rows) through unguarded. Enable only in controlled contexts:
			 *   add_filter( 'wpdo_allow_mass_column_clear', '__return_true' );
			 *
			 * @param bool   $allow    Whether to allow the mass clear. Default false.
			 * @param string $table    Flat table name.
			 * @param string $col      Column being cleared.
			 * @param string $meta_key Original meta key.
			 */
			$allowed = (bool) apply_filters( 'wpdo_allow_mass_column_clear', false, $table, $col, $meta_key );
			/** This filter is documented above (tmdo_* is the forward-looking name). */
			$allowed = (bool) apply_filters( 'tmdo_allow_mass_column_clear', $allowed, $table, $col, $meta_key );

			if ( ! $allowed ) {
				TMDO_Logger::warning(
					'intercept_delete_mass_blocked',
					array(
						'table'  => $table,
						'col'    => $col,
						'reason' => 'enable via wpdo_allow_mass_column_clear filter',
					)
				);
				return false;
			}

			// phpcs:ignore WordPress.DB.DirectDatabaseQuery,WordPress.DB.DirectDatabaseQuery.NoCaching,WordPress.DB.PreparedSQL.InterpolatedNotPrepared
			$row_count = (int) $wpdb->get_var( "SELECT COUNT(*) FROM `{$table}`" );

			TMDO_Logger::warning(
				'intercept_delete_all',
				array(
					'table' => $table,
					'col'   => $col,
					'rows'  => $row_count,
				)
			);

			// 刪除所有 entity 的該欄位
			$result = $wpdb->query(
				$wpdb->prepare(
					"UPDATE `{$table}` SET `{$col}` = %s",
					$default
				)
			);
		} else {
			$result = $wpdb->update(
				$table,
				array( $col => $default ),
				array( $id_col => $object_id ),
				array( TMDO_Type_Caster::get_wpdb_format( $field_def['type'] ) ),
				array( '%d' )
			);

			TMDO_Cache_Orchestrator::invalidate( $type, (int) $object_id, $group );
		}

		do_action( 'wpdo_after_delete', $type, (int) $object_id, $meta_key, $meta_value, $result, (bool) $delete_all, $before_value );

		// 若還要寫 EAV → return null 讓 WP 繼續刪除原生 meta
		if ( TMDO_Mode_Manager::writes_to_eav( $type ) ) {
			return null;
		}

		return $result !== false;
	}

	// ─────────────────────────────────────────────────────────
	// 實體刪除清理
	// ─────────────────────────────────────────────────────────

	public static function cleanup_entity( string $type, int $entity_id ): void {
		global $wpdb;

		$adapter = TMDO_Entity_Registry::get_adapter( $type );
		if ( ! $adapter ) {
			return;
		}

		$id_col = $adapter->get_entity_id_column();
		$groups = TMDO_Entity_Registry::get_groups_for_type( $type );

		foreach ( $groups as $group ) {
			$table = TMDO_Schema_Manager::get_table_name( $type, $group );
			if ( TMDO_Schema_Manager::table_exists( $table ) ) {
				$wpdb->delete( $table, array( $id_col => $entity_id ), array( '%d' ) );
			}
		}

		TMDO_Cache_Orchestrator::flush_entity( $type, $entity_id );
	}

	// ─────────────────────────────────────────────────────────
	// 工具方法
	// ─────────────────────────────────────────────────────────

	/**
	 * 從當前 filter 名稱推斷實體類型
	 * 例：update_user_metadata → user
	 */
	private static function resolve_type_from_current_filter(): ?string {
		$current = current_filter();

		if ( preg_match( '/^(?:add|get|update|delete)_(post|user|term|comment)_metadata$/', $current, $matches ) ) {
			return $matches[1];
		}

		return null;
	}

	/**
	 * 直接讀取（繞過 WP filter 系統）
	 * 供 wpdo_get_meta() 便利函式使用，性能更好
	 *
	 * @param string $type
	 * @param int    $entity_id
	 * @param string $key 若為空字串則回傳整列
	 * @return mixed
	 */
	public static function direct_read( string $type, int $entity_id, string $key = '' ) {

		if ( $key === '' ) {
			// 回傳所有群組的所有欄位
			$result = array();
			foreach ( TMDO_Entity_Registry::get_groups_for_type( $type ) as $group ) {
				$row = self::get_or_load_row( $type, $entity_id, $group );
				foreach ( TMDO_Entity_Registry::get_group_fields( $type, $group ) as $field ) {
					$col                     = TMDO_Schema_Manager::sanitize_column_name( $field['key'] );
					$result[ $field['key'] ] = TMDO_Type_Caster::from_db( $row[ $col ] ?? null, $field );
				}
			}
			return $result;
		}

		$field_def = TMDO_Entity_Registry::get_field( $type, $key );
		if ( ! $field_def ) {
			return null;
		}

		$row = self::get_or_load_row( $type, $entity_id, $field_def['group'] );
		$col = TMDO_Schema_Manager::sanitize_column_name( $key );
		return TMDO_Type_Caster::from_db( $row[ $col ] ?? null, $field_def );
	}
}