from session.db import SessionDB


class SessionReplay:

    def __init__(self, db: SessionDB):
        self.db = db

    # -----------------------------
    # REPLAY SESSION
    # -----------------------------
    def replay(self, session_id):

        stream = self.db.get_replay_stream(session_id)

        for event in stream:

            yield {
                "ts": event["ts"],
                "type": event["type"],
                "data": event["data"]
            }

    # -----------------------------
    # REPLAY FROM SNAPSHOT
    # -----------------------------
    def replay_from_snapshot(self, session_id, index=0):

        snapshots = self.db.snapshots[session_id]

        if not snapshots:
            return []

        base = snapshots[index]

        return {
            "snapshot": base,
            "events_after": [
                e for e in self.db.events[session_id]
                if e["ts"] >= base["ts"]
            ]
        }