import pytest
from fastapi.testclient import TestClient

from app.core.auth_dependency import require_session
from app.db import get_db
from app.main import app
from app.models.channel import Channel
from app.services import sync
from app.services.youtube_client import YouTubeInsufficientScope


@pytest.fixture
def client(db_session):
    def _get_db_override():
        yield db_session

    app.dependency_overrides[get_db] = _get_db_override
    app.dependency_overrides[require_session] = lambda: None
    # Deliberately not using `with TestClient(app)`: that runs the app's
    # lifespan, which would try to reach the real MeTube instance and DB.
    yield TestClient(app)
    del app.dependency_overrides[get_db]
    del app.dependency_overrides[require_session]


def _seed_channel(db_session, youtube_subscription_id="sub1"):
    channel = Channel(
        youtube_channel_id="chanA",
        youtube_subscription_id=youtube_subscription_id,
        title="Channel A",
        subscribed=True,
    )
    db_session.add(channel)
    db_session.commit()
    db_session.refresh(channel)
    return channel


def test_unsubscribe_success(client, db_session, monkeypatch):
    channel = _seed_channel(db_session)

    monkeypatch.setattr(sync.google_oauth, "get_credentials", lambda db: object())
    calls = {}
    monkeypatch.setattr(
        sync.youtube_client,
        "unsubscribe",
        lambda creds, sub_id: calls.setdefault("sub_id", sub_id),
    )

    resp = client.post(f"/api/channels/{channel.id}/unsubscribe")

    assert resp.status_code == 200
    assert resp.json()["subscribed"] is False
    assert calls["sub_id"] == "sub1"

    db_session.refresh(channel)
    assert channel.subscribed is False


def test_unsubscribe_without_subscription_id_returns_400(client, db_session):
    channel = _seed_channel(db_session, youtube_subscription_id=None)

    resp = client.post(f"/api/channels/{channel.id}/unsubscribe")

    assert resp.status_code == 400


def test_unsubscribe_insufficient_scope_returns_403(client, db_session, monkeypatch):
    channel = _seed_channel(db_session)

    monkeypatch.setattr(sync.google_oauth, "get_credentials", lambda db: object())

    def raise_insufficient(creds, sub_id):
        raise YouTubeInsufficientScope("Request had insufficient authentication scopes.")

    monkeypatch.setattr(sync.youtube_client, "unsubscribe", raise_insufficient)

    resp = client.post(f"/api/channels/{channel.id}/unsubscribe")

    assert resp.status_code == 403

    db_session.refresh(channel)
    assert channel.subscribed is True


def test_unsubscribe_channel_not_found(client):
    resp = client.post("/api/channels/9999/unsubscribe")
    assert resp.status_code == 404