lruTouchHook function

HiHook lruTouchHook({ String uid = 'lru:touch', List<String> events = const ['read', 'get'], String metaKey = 'meta', String lastAccessedKey = 'last_accessed', String accessCountKey = 'access_count', bool trackAccessCount = false, int nowProvider()?, HiPhase phase = HiPhase.post, int priority = 0, })

Creates an LRU touch hook that updates access metadata on read.

Updates:

• last_accessed: Current timestamp
• access_count: Incremented by 1 (if tracking enabled)

Consumer should persist meta after emit if wasWritten('meta').

Parameters

• uid: Unique hook identifier, defaults to 'lru:touch'
• events: Events to listen for, defaults to 'read', 'get'
• metaKey: Key in ctx.data for metadata
• lastAccessedKey: Key in meta for last access timestamp
• accessCountKey: Key in meta for access count
• trackAccessCount: Whether to track access count
• nowProvider: Function to get current time

Example

engine.register(lruTouchHook());

// Or with custom configuration
engine.register(lruTouchHook(
  events: ['read'],
  trackAccessCount: true,
));

Implementation

HiHook<dynamic, dynamic> lruTouchHook({
  String uid = 'lru:touch',
  List<String> events = const ['read', 'get'],
  String metaKey = 'meta',
  String lastAccessedKey = 'last_accessed',
  String accessCountKey = 'access_count',
  bool trackAccessCount = false,
  int Function()? nowProvider,
  HiPhase phase = HiPhase.post,
  int priority = 0,
}) {
  return HiHook<dynamic, dynamic>(
    uid: uid,
    events: events,
    phase: phase,
    priority: priority,
    handler: (payload, ctx) {
      final context = ctx as HiContext;
      final meta = Map<String, dynamic>.from(
        context.dataTracked[metaKey] as Map<String, dynamic>? ?? {},
      );

      // Update last accessed timestamp
      meta[lastAccessedKey] = nowProvider?.call() ??
          DateTime.now().millisecondsSinceEpoch;

      // Optionally track access count
      if (trackAccessCount) {
        final currentCount = meta[accessCountKey] as int? ?? 0;
        meta[accessCountKey] = currentCount + 1;
      }

      context.dataTracked[metaKey] = meta;
      return const HiContinue();
    },
  );
}