CA/backend/tests/test_auth.py

"""US-003: Authentication and security tests."""
import pytest
from fastapi.testclient import TestClient


class TestLogin:
    def test_login_success(self, client: TestClient):
        resp = client.post("/api/auth/login", json={
            "username": "admin", "password": "admin123"
        })
        assert resp.status_code == 200
        data = resp.json()
        assert "access_token" in data
        assert len(data["access_token"]) > 0

    def test_login_wrong_password(self, client: TestClient):
        resp = client.post("/api/auth/login", json={
            "username": "admin", "password": "wrongpassword"
        })
        assert resp.status_code == 401
        assert "Incorrect username or password" in resp.json()["detail"]

    def test_login_nonexistent_user(self, client: TestClient):
        resp = client.post("/api/auth/login", json={
            "username": "nonexistent_user_xyz", "password": "password"
        })
        assert resp.status_code == 401

    def test_login_empty_username(self, client: TestClient):
        resp = client.post("/api/auth/login", json={
            "username": "", "password": "password"
        })
        assert resp.status_code in (401, 422)


class TestRegister:
    def test_register_new_user(self, client: TestClient):
        resp = client.post("/api/auth/register", json={
            "username": "testuser_001", "password": "testpass123"
        })
        assert resp.status_code == 201
        assert resp.json()["username"] == "testuser_001"

    def test_register_duplicate(self, client: TestClient):
        client.post("/api/auth/register", json={
            "username": "dup_user", "password": "testpass123"
        })
        resp = client.post("/api/auth/register", json={
            "username": "dup_user", "password": "testpass123"
        })
        assert resp.status_code == 409
        assert "already exists" in resp.json()["detail"]

    def test_register_missing_password(self, client: TestClient):
        resp = client.post("/api/auth/register", json={"username": "user"})
        assert resp.status_code == 422


class TestTokenAuth:
    def test_me_with_valid_token(self, client: TestClient, auth_token):
        resp = client.get(
            "/api/auth/me",
            headers={"Authorization": f"Bearer {auth_token}"}
        )
        assert resp.status_code == 200
        assert resp.json()["username"] == "admin"

    def test_me_without_token(self, client: TestClient):
        resp = client.get("/api/auth/me")
        assert resp.status_code in (401, 403)

    def test_me_with_invalid_token(self, client: TestClient):
        resp = client.get(
            "/api/auth/me",
            headers={"Authorization": "Bearer invalid.token.here"}
        )
        assert resp.status_code in (401, 403)

    def test_me_with_malformed_header(self, client: TestClient):
        resp = client.get(
            "/api/auth/me",
            headers={"Authorization": "NotBearer token"}
        )
        assert resp.status_code in (401, 403)

    def test_me_with_expired_token(self, client: TestClient):
        """Token with past expiration should be rejected."""
        expired = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJhZG1pbiIsImV4cCI6MTcwMDAwMDAwMH0.fake"
        resp = client.get(
            "/api/auth/me",
            headers={"Authorization": f"Bearer {expired}"}
        )
        assert resp.status_code in (401, 403)

    def test_login_then_access_protected(self, client: TestClient):
        login_resp = client.post("/api/auth/login", json={
            "username": "admin", "password": "admin123"
        })
        token = login_resp.json()["access_token"]

        resp = client.get(
            "/api/auth/me",
            headers={"Authorization": f"Bearer {token}"}
        )
        assert resp.status_code == 200
        assert resp.json()["username"] == "admin"


class TestPasswordHashing:
    def test_bcrypt_not_plaintext(self, client: TestClient):
        """Passwords should be hashed, not stored as plaintext."""
        from auth.service import hash_password, verify_password
        hashed = hash_password("test_password")
        assert hashed != "test_password"
        assert verify_password("test_password", hashed)
        assert not verify_password("wrong_password", hashed)