from app.models.channel import Channel
from app.models.video import Video
from app.services import sync


def _fake_credentials():
    return object()


def test_sync_subscriptions_idempotent_and_unsubscribes(monkeypatch, db_session):
    monkeypatch.setattr(sync.google_oauth, "get_credentials", lambda db: _fake_credentials())
    monkeypatch.setattr(
        sync.youtube_client,
        "fetch_subscriptions",
        lambda creds: [
            {"youtube_channel_id": "chanA", "title": "Channel A", "description": "d", "thumbnail_url": "t"},
            {"youtube_channel_id": "chanB", "title": "Channel B", "description": "d", "thumbnail_url": "t"},
        ],
    )
    monkeypatch.setattr(
        sync.youtube_client,
        "fetch_uploads_playlists",
        lambda creds, ids: {cid: f"UU{cid}" for cid in ids},
    )

    result = sync.sync_subscriptions(db_session)

    assert result["status"] == "completed"
    assert result["channels_added"] == 2
    assert result["channels_unsubscribed"] == 0

    channels = db_session.query(Channel).order_by(Channel.youtube_channel_id).all()
    assert [c.youtube_channel_id for c in channels] == ["chanA", "chanB"]
    assert all(c.subscribed for c in channels)
    assert channels[0].uploads_playlist_id == "UUchanA"

    # Second sync: chanA disappears from subscriptions, chanC appears.
    monkeypatch.setattr(
        sync.youtube_client,
        "fetch_subscriptions",
        lambda creds: [
            {"youtube_channel_id": "chanB", "title": "Channel B", "description": "d", "thumbnail_url": "t"},
            {"youtube_channel_id": "chanC", "title": "Channel C", "description": "d", "thumbnail_url": "t"},
        ],
    )

    result2 = sync.sync_subscriptions(db_session)

    assert result2["channels_added"] == 1
    assert result2["channels_updated"] == 1
    assert result2["channels_unsubscribed"] == 1

    channels = {c.youtube_channel_id: c for c in db_session.query(Channel).all()}
    assert len(channels) == 3
    assert channels["chanA"].subscribed is False
    assert channels["chanB"].subscribed is True
    assert channels["chanC"].subscribed is True


def test_sync_in_progress_raises(monkeypatch, db_session):
    sync._subscriptions_lock.acquire()
    try:
        try:
            sync.sync_subscriptions(db_session)
            assert False, "expected SyncInProgress"
        except sync.SyncInProgress:
            pass
    finally:
        sync._subscriptions_lock.release()


def _seed_channel(db_session, youtube_channel_id="chanA", uploads_playlist_id="UUchanA"):
    channel = Channel(
        youtube_channel_id=youtube_channel_id,
        title="Channel",
        subscribed=True,
        uploads_playlist_id=uploads_playlist_id,
    )
    db_session.add(channel)
    db_session.commit()
    db_session.refresh(channel)
    return channel


def test_sync_videos_adds_and_updates(monkeypatch, db_session):
    channel = _seed_channel(db_session)

    monkeypatch.setattr(sync.google_oauth, "get_credentials", lambda db: object())
    monkeypatch.setattr(
        sync.youtube_client, "fetch_playlist_video_ids", lambda creds, playlist_id, max_results: ["vid1"]
    )
    monkeypatch.setattr(
        sync.youtube_client,
        "fetch_videos_details",
        lambda creds, ids: [
            {
                "youtube_video_id": "vid1",
                "youtube_channel_id": channel.youtube_channel_id,
                "title": "Video One",
                "description": "d",
                "thumbnail_url": "t",
                "published_at": "2026-09-10T12:00:00Z",
                "duration_iso8601": "PT5M",
            }
        ],
    )

    result = sync.sync_videos(db_session)

    assert result["status"] == "completed"
    assert result["videos_added"] == 1

    video = db_session.query(Video).filter_by(youtube_video_id="vid1").one()
    assert video.title == "Video One"
    assert video.duration_seconds == 300
    assert video.youtube_url == "https://www.youtube.com/watch?v=vid1"

    monkeypatch.setattr(
        sync.youtube_client,
        "fetch_videos_details",
        lambda creds, ids: [
            {
                "youtube_video_id": "vid1",
                "youtube_channel_id": channel.youtube_channel_id,
                "title": "Video One Updated",
                "description": "d2",
                "thumbnail_url": "t2",
                "published_at": "2026-09-10T12:00:00Z",
                "duration_iso8601": "PT6M",
            }
        ],
    )

    result2 = sync.sync_videos(db_session)
    assert result2["videos_added"] == 0
    assert result2["videos_updated"] == 1

    videos = db_session.query(Video).all()
    assert len(videos) == 1
    assert videos[0].title == "Video One Updated"


def test_sync_videos_skips_unknown_channel(monkeypatch, db_session):
    _seed_channel(db_session, "chanA")

    monkeypatch.setattr(sync.google_oauth, "get_credentials", lambda db: object())
    monkeypatch.setattr(sync.youtube_client, "fetch_playlist_video_ids", lambda creds, playlist_id, max_results: [])
    monkeypatch.setattr(
        sync.youtube_client,
        "fetch_videos_details",
        lambda creds, ids: [
            {
                "youtube_video_id": "vidX",
                "youtube_channel_id": "unknown-channel",
                "title": "Orphan",
                "description": "",
                "thumbnail_url": None,
                "published_at": "2026-09-10T12:00:00Z",
                "duration_iso8601": None,
            }
        ],
    )

    result = sync.sync_videos(db_session)

    assert result["videos_skipped"] == 1
    assert db_session.query(Video).count() == 0