<?php
/**
 * TMDO_Conflict_Monitor — production-time conflict detection for WPDO.
 *
 * Wraps TMDO_Hook_Bus_Bridge::detect_intra_wpdo_conflicts() and the UAE-port
 * TMDO_Conflict_Detector (UAEPG cross-plugin scan) into a single facade with:
 *
 *   - admin_init scan + admin_notices warning when conflicts detected
 *   - admin_bar warning chip when conflicts > 0 (Part C.1 enforcer requirement)
 *   - Persistent log to wpdo_audit table for ops review
 *   - Single-source-of-truth `get_all_conflicts()` for CLI / REST surfaces
 *
 * This wrapper is the live monitor; the engine/class-tmdo-conflict-detector.php
 * is the deeper UAEPG-aware scanner. The split keeps WPDO callable without
 * UAEPG present.
 *
 * @package WP_Data_Optimizer
 * @since   2.0.0
 */

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

// phpcs:disable Squiz.Commenting.FunctionComment.Missing,Squiz.Commenting.InlineComment.InvalidEndChar,Generic.Commenting.DocComment.MissingShort,WordPress.DB.PreparedSQL.InterpolatedNotPrepared,WordPress.PHP.YodaConditions,Generic.CodeAnalysis.EmptyStatement -- v2.0.0 partner integrations: pure registration helpers + intentional silent catches.

/**
 * Production conflict monitor with admin surface integration.
 */
final class TMDO_Conflict_Monitor {

	/**
	 * Cached conflict list per request.
	 *
	 * @var array<int, array{type:string, hook?:string, priority?:int, callback?:string, entity_type?:string, meta_key?:string}>|null
	 */
	private static ?array $cache = null;

	/**
	 * Register all hooks for production monitor surface.
	 *
	 * Called from TMDO_Core::run() after all interceptors register.
	 *
	 * @return void
	 */
	public static function register_hooks(): void {
		// init:30 — runs after both wpdo_register_fields (init:20) and the
		// UAE-port Conflict_Detector (init:25), so we observe a complete picture.
		add_action( 'init', array( self::class, 'scan' ), 30 );

		if ( is_admin() ) {
			add_action( 'admin_notices', array( self::class, 'maybe_render_admin_notice' ) );
			add_action( 'admin_bar_menu', array( self::class, 'maybe_render_admin_bar' ), 999 );
		}
	}

	/**
	 * Run a full scan and cache the result for the request.
	 *
	 * Aggregates findings from:
	 *   1. TMDO_Hook_Bus_Bridge::detect_intra_wpdo_conflicts() — same-hook callback overlap
	 *   2. TMDO_Conflict_Detector::scan() — UAEPG cross-plugin field overlap (if present)
	 *
	 * @return array<int, array>
	 */
	public static function scan(): array {
		if ( null !== self::$cache ) {
			return self::$cache;
		}

		$conflicts = array();

		if ( class_exists( 'TMDO_Hook_Bus_Bridge' ) ) {
			foreach ( TMDO_Hook_Bus_Bridge::detect_intra_wpdo_conflicts() as $finding ) {
				$conflicts[] = array_merge( array( 'type' => 'hook_overlap' ), $finding );
			}
		}

		if ( class_exists( 'TMDO_Conflict_Detector' ) ) {
			foreach ( TMDO_Conflict_Detector::scan() as $finding ) {
				$conflicts[] = array_merge( array( 'type' => 'uaepg_overlap' ), $finding );
			}
		}

		self::$cache = $conflicts;

		// Persist a single summary row to wpdo_audit when conflicts exist.
		if ( $conflicts ) {
			self::persist_audit_summary( $conflicts );
		}

		return $conflicts;
	}

	/**
	 * Get the cached conflict list, scanning lazily if needed.
	 *
	 * @return array<int, array>
	 */
	public static function get_all_conflicts(): array {
		return self::$cache ?? self::scan();
	}

	/**
	 * Conflict count by type.
	 *
	 * @return array{total:int, hook_overlap:int, uaepg_overlap:int}
	 */
	public static function get_summary(): array {
		$conflicts = self::get_all_conflicts();
		$summary   = array(
			'total'         => count( $conflicts ),
			'hook_overlap'  => 0,
			'uaepg_overlap' => 0,
		);
		foreach ( $conflicts as $c ) {
			$type = $c['type'] ?? 'unknown';
			if ( isset( $summary[ $type ] ) ) {
				++$summary[ $type ];
			}
		}
		return $summary;
	}

	/**
	 * Reset request cache. Test helper.
	 *
	 * @internal
	 */
	public static function reset_cache(): void {
		self::$cache = null;
	}

	/**
	 * Render an admin notice when conflicts are present.
	 *
	 * @return void
	 */
	public static function maybe_render_admin_notice(): void {
		if ( ! TMDO_Capability::current_user_can_admin() ) {
			return;
		}
		$summary = self::get_summary();
		if ( $summary['total'] === 0 ) {
			return;
		}

		$message = sprintf(
			/* translators: %d: conflict count */
			esc_html__( 'WPDO Conflict Detector：偵測到 %d 個欄位 / hook 衝突 — 可能造成資料靜默遺失。', '2meet-data-optimizer' ),
			$summary['total']
		);
		$link = esc_url( admin_url( 'tools.php?page=wp-data-optimizer&tab=conflicts' ) );

		printf(
			'<div class="notice notice-error"><p>%s <a href="%s">%s</a></p></div>',
			esc_html( $message ),
			esc_url( $link ),
			esc_html__( '查看詳情', '2meet-data-optimizer' )
		);
	}

	/**
	 * Render a warning chip in the admin bar.
	 *
	 * @param mixed $wp_admin_bar WP_Admin_Bar instance.
	 * @return void
	 */
	public static function maybe_render_admin_bar( $wp_admin_bar ): void {
		if ( ! is_object( $wp_admin_bar ) || ! method_exists( $wp_admin_bar, 'add_node' ) ) {
			return;
		}
		if ( ! TMDO_Capability::current_user_can_admin() ) {
			return;
		}
		$summary = self::get_summary();
		if ( $summary['total'] === 0 ) {
			return;
		}

		$wp_admin_bar->add_node(
			array(
				'id'    => 'wpdo-conflicts',
				'title' => sprintf(
					/* translators: %d: conflict count */
					'⚠️ ' . esc_html__( 'Anti-EAV: %d conflicts', '2meet-data-optimizer' ),
					$summary['total']
				),
				'href'  => admin_url( 'tools.php?page=wp-data-optimizer&tab=conflicts' ),
				'meta'  => array( 'class' => 'wpdo-conflict-warning' ),
			)
		);
	}

	/**
	 * Persist a summary row to wpdo_audit (silently swallows errors when table missing).
	 *
	 * @param array<int,array> $conflicts All findings.
	 * @return void
	 */
	private static function persist_audit_summary( array $conflicts ): void {
		try {
			global $wpdb;
			$table = $wpdb->prefix . 'wpdo_audit';
			$wpdb->insert(
				$table,
				array(
					'ts'           => current_time( 'mysql' ),
					'user_id'      => 0,
					'entity_type'  => 'system',
					'entity_id'    => 0,
					'meta_key'     => '',
					'op'           => 'conflict_scan',
					'value_before' => null,
					'value_after'  => wp_json_encode( $conflicts ),
					'source'       => 'monitor',
					'trace_id'     => self::generate_trace_id(),
				),
				array( '%s', '%d', '%s', '%d', '%s', '%s', '%s', '%s', '%s', '%s' )
			);
		} catch ( \Throwable $e ) {
			// wpdo_audit not yet installed (pre-v2 upgrade) — skip silently.
		}
	}

	/**
	 * Generate a UUID-like trace id (v4-ish, no external deps).
	 *
	 * @return string
	 */
	private static function generate_trace_id(): string {
		// PHP 8.1+ random_bytes is always available.
		try {
			$bytes = random_bytes( 16 );
		} catch ( \Throwable $e ) {
			$bytes = pack( 'H*', md5( (string) microtime( true ) . wp_generate_password( 16, false ) ) );
		}
		$bytes[6] = chr( ( ord( $bytes[6] ) & 0x0f ) | 0x40 );
		$bytes[8] = chr( ( ord( $bytes[8] ) & 0x3f ) | 0x80 );
		return vsprintf(
			'%s%s-%s-%s-%s-%s%s%s',
			str_split( bin2hex( $bytes ), 4 )
		);
	}
}