"""
Auth tests — Casdoor JWT + PAT resolution, owner gating, dev-owner mode.

No live Casdoor: we generate an RSA keypair, stub the JWKS client so
`_decode_casdoor_jwt` trusts our public key, and mint RS256 JWTs locally.
The app is exercised without its lifespan, so a 503 ("Gateway not
initialized") proves auth was accepted and the request reached a handler.

DB access (resolve_bearer → users/PATs) hits an in-memory SQLite database
wired in via the `mem_db` fixture, mirroring tests/test_data_layer.py.
"""

import time
import uuid

import httpx
import jwt
import pytest
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric import rsa
from sqlalchemy.ext.asyncio import async_sessionmaker, create_async_engine
from sqlalchemy.pool import StaticPool

import auth as authmod
import db.database as dbmod
import main
from config import get_settings
from db.database import Base, PersonalAccessToken, User

ENDPOINT = "https://id.example.test"
OWNER = "owner@example.test"


# ── RSA keypair + JWKS stub ──────────────────────────────────────────────────


@pytest.fixture(scope="module")
def keypair():
    key = rsa.generate_private_key(public_exponent=65537, key_size=2048)
    private_pem = key.private_bytes(
        serialization.Encoding.PEM,
        serialization.PrivateFormat.PKCS8,
        serialization.NoEncryption(),
    )
    return private_pem, key.public_key()


def _mint(private_pem, *, sub, name, email=None, exp_delta=3600):
    claims = {
        "iss": ENDPOINT,
        "sub": sub,
        "name": name,
        "displayName": name,
        "exp": int(time.time()) + exp_delta,
        "iat": int(time.time()),
    }
    if email:
        claims["email"] = email
    return jwt.encode(claims, private_pem, algorithm="RS256")


class _StubJWKS:
    """Stands in for jwt.PyJWKClient — returns our fixed public key."""

    def __init__(self, public_key):
        self._key = public_key

    def get_signing_key_from_jwt(self, token):
        class _K:
            key = self._key

        return _K()

    def fetch_data(self):
        pass


@pytest.fixture
def sso_enabled(monkeypatch, keypair):
    """Enable Casdoor SSO with a known owner and a stubbed JWKS client."""
    _, public_key = keypair
    settings = get_settings()
    monkeypatch.setattr(settings.casdoor, "enabled", True)
    monkeypatch.setattr(settings.casdoor, "endpoint", ENDPOINT)
    monkeypatch.setattr(settings, "owner_name", OWNER)
    monkeypatch.setattr(authmod, "_jwks_client", _StubJWKS(public_key))


@pytest.fixture
async def mem_db(monkeypatch):
    engine = create_async_engine(
        "sqlite+aiosqlite:///:memory:",
        poolclass=StaticPool,
        connect_args={"check_same_thread": False},
    )
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
    factory = async_sessionmaker(engine, expire_on_commit=False)
    monkeypatch.setattr(dbmod, "_engine", engine)
    monkeypatch.setattr(dbmod, "_session_factory", factory)
    yield factory
    await engine.dispose()


@pytest.fixture
async def client():
    transport = httpx.ASGITransport(app=main.app)
    async with httpx.AsyncClient(transport=transport, base_url="http://test") as c:
        yield c


async def _seed_user(factory, *, name, casdoor_sub=None, email=None) -> str:
    uid = uuid.uuid4().hex
    async with factory() as session:
        session.add(
            User(id=uid, name=name, display_name=name, email=email, casdoor_sub=casdoor_sub)
        )
        await session.commit()
    return uid


async def _seed_pat(factory, user_id, *, revoked=False, expires_at=None) -> str:
    from datetime import UTC, datetime

    plaintext = authmod.PAT_PREFIX + uuid.uuid4().hex
    async with factory() as session:
        pat = PersonalAccessToken(
            id=uuid.uuid4().hex,
            user_id=user_id,
            name="test",
            token_hash=authmod.hash_token(plaintext),
            token_prefix=plaintext[: len(authmod.PAT_PREFIX) + 4],
            revoked_at=(datetime.now(UTC) if revoked else None),
            expires_at=expires_at,
        )
        session.add(pat)
        await session.commit()
    return plaintext


PROTECTED = "/api/v1/calls/active"


# ── JWT paths ────────────────────────────────────────────────────────────────


class TestCasdoorJWT:
    async def test_owner_jwt_reaches_handler(self, sso_enabled, mem_db, client, keypair):
        private_pem, _ = keypair
        token = _mint(private_pem, sub="s-owner", name=OWNER, email=OWNER)
        resp = await client.get(PROTECTED, headers={"Authorization": f"Bearer {token}"})
        assert resp.status_code == 503  # auth accepted; no lifespan → handler 503s

    async def test_non_owner_jwt_forbidden(self, sso_enabled, mem_db, client, keypair):
        private_pem, _ = keypair
        token = _mint(private_pem, sub="s-guest", name="guest@example.test")
        resp = await client.get(PROTECTED, headers={"Authorization": f"Bearer {token}"})
        assert resp.status_code == 403

    async def test_expired_jwt_unauthenticated(self, sso_enabled, mem_db, client, keypair):
        private_pem, _ = keypair
        token = _mint(private_pem, sub="s-owner", name=OWNER, exp_delta=-10)
        resp = await client.get(PROTECTED, headers={"Authorization": f"Bearer {token}"})
        assert resp.status_code == 401

    async def test_garbage_token_unauthenticated(self, sso_enabled, mem_db, client):
        resp = await client.get(PROTECTED, headers={"Authorization": "Bearer not.a.jwt"})
        assert resp.status_code == 401

    async def test_no_credentials_unauthenticated(self, sso_enabled, mem_db, client):
        resp = await client.get(PROTECTED)
        assert resp.status_code == 401
        assert resp.headers["www-authenticate"] == "Bearer"


# ── PAT paths ────────────────────────────────────────────────────────────────


class TestPAT:
    async def test_owner_pat_reaches_handler(self, sso_enabled, mem_db, client):
        uid = await _seed_user(mem_db, name=OWNER, casdoor_sub="s-owner", email=OWNER)
        pat = await _seed_pat(mem_db, uid)
        resp = await client.get(PROTECTED, headers={"Authorization": f"Bearer {pat}"})
        assert resp.status_code == 503

    async def test_non_owner_pat_forbidden(self, sso_enabled, mem_db, client):
        uid = await _seed_user(mem_db, name="guest@example.test", casdoor_sub="s-guest")
        pat = await _seed_pat(mem_db, uid)
        resp = await client.get(PROTECTED, headers={"Authorization": f"Bearer {pat}"})
        assert resp.status_code == 403

    async def test_revoked_pat_unauthenticated(self, sso_enabled, mem_db, client):
        uid = await _seed_user(mem_db, name=OWNER, casdoor_sub="s-owner", email=OWNER)
        pat = await _seed_pat(mem_db, uid, revoked=True)
        resp = await client.get(PROTECTED, headers={"Authorization": f"Bearer {pat}"})
        assert resp.status_code == 401

    async def test_expired_pat_unauthenticated(self, sso_enabled, mem_db, client):
        from datetime import UTC, datetime, timedelta

        uid = await _seed_user(mem_db, name=OWNER, casdoor_sub="s-owner", email=OWNER)
        pat = await _seed_pat(mem_db, uid, expires_at=datetime.now(UTC) - timedelta(minutes=1))
        resp = await client.get(PROTECTED, headers={"Authorization": f"Bearer {pat}"})
        assert resp.status_code == 401

    async def test_unknown_pat_unauthenticated(self, sso_enabled, mem_db, client):
        resp = await client.get(
            PROTECTED, headers={"Authorization": f"Bearer {authmod.PAT_PREFIX}nope"}
        )
        assert resp.status_code == 401


# ── Dev-owner mode (SSO disabled) ────────────────────────────────────────────


class TestDevOwnerMode:
    async def test_tokenless_request_is_owner(self, monkeypatch, mem_db, client):
        monkeypatch.setattr(get_settings().casdoor, "enabled", False)
        resp = await client.get(PROTECTED)
        assert resp.status_code == 503  # dev-owner resolved; handler 503s (no lifespan)

    async def test_auth_me_reports_owner(self, monkeypatch, mem_db, client):
        monkeypatch.setattr(get_settings().casdoor, "enabled", False)
        resp = await client.get("/auth/me")
        assert resp.status_code == 200
        body = resp.json()
        assert body["is_owner"] is True


# ── /auth/me for a non-owner (200 + is_owner:false, not a hard 401) ──────────


class TestAuthMe:
    async def test_non_owner_gets_200_not_owner(self, sso_enabled, mem_db, client, keypair):
        private_pem, _ = keypair
        token = _mint(private_pem, sub="s-guest", name="guest@example.test")
        resp = await client.get("/auth/me", headers={"Authorization": f"Bearer {token}"})
        assert resp.status_code == 200
        assert resp.json()["is_owner"] is False