import time
from collections import OrderedDict

from .defaults import SEEN_MAX_ENTRIES, SEEN_TTL_MS, SEEN_PRUNE_INTERVAL_S


class SeenTracker:
    def __init__(self, max_entries: int = SEEN_MAX_ENTRIES, ttl_ms: int = SEEN_TTL_MS):
        self.max_entries = max_entries
        self.ttl_s = ttl_ms / 1000
        self._store: OrderedDict[str, float] = OrderedDict()
        self._last_prune = time.monotonic()

    def peek(self, event_id: str) -> bool:
        self._maybe_prune()
        return event_id in self._store

    def has(self, event_id: str) -> bool:
        self._maybe_prune()
        if event_id in self._store:
            self._store.move_to_end(event_id)
            return True
        self._store[event_id] = time.monotonic()
        if len(self._store) > self.max_entries:
            self._store.popitem(last=False)
        return False

    def seed(self, ids: list[str]):
        now = time.monotonic()
        for eid in ids:
            self._store[eid] = now
        while len(self._store) > self.max_entries:
            self._store.popitem(last=False)

    @property
    def size(self) -> int:
        return len(self._store)

    def get_recent_ids(self, limit: int = 5000) -> list[str]:
        return list(self._store.keys())[-limit:]

    def _maybe_prune(self):
        now = time.monotonic()
        if now - self._last_prune < SEEN_PRUNE_INTERVAL_S:
            return
        self._last_prune = now
        expired = [k for k, ts in self._store.items() if now - ts > self.ttl_s]
        for k in expired:
            del self._store[k]