"""Per-frame detect + group + track + capture + emit pipeline."""
from __future__ import annotations

from pathlib import Path
from typing import Dict

from saqr.core.capture import save_track_image
from saqr.core.detection import collect_detections
from saqr.core.drawing import draw_track
from saqr.core.events import emit_event, write_result_csv
from saqr.core.grouping import group_detections_to_people
from saqr.core.paths import RESULT_CSV
from saqr.core.tracking import PersonTracker


def process_frame(frame, model, tracker: PersonTracker, frame_idx: int, conf: float,
                  capture_dirs: Dict[str, Path], write_csv: bool = True):
    annotated = frame.copy()
    h, w = annotated.shape[:2]

    detections = collect_detections(frame, model, conf)
    candidates = group_detections_to_people(detections, w, h)
    created, changed = tracker.update(candidates, frame_idx)
    visible = tracker.visible_tracks()

    created_ids = {t.track_id for t in created}
    changed_ids = {t.track_id for t in changed}
    event_ids = created_ids | changed_ids

    for track in visible:
        save_track_image(frame, track, capture_dirs)
        if track.track_id in event_ids:
            ev_type = "NEW" if track.track_id in created_ids else "STATUS_CHANGE"
            emit_event(track, tracker.event_logger, ev_type)
        draw_track(annotated, track)

    if write_csv:
        write_result_csv(list(tracker.tracks.values()), RESULT_CSV)

    return annotated, visible