"""Tests for auth routes: register, login, refresh, me, OAuth social login.

Exercises the full auth lifecycle through the FastAPI TestClient against the
in-memory SQLite test database seeded by ``conftest.py``.
"""

from __future__ import annotations

import time
from unittest.mock import AsyncMock, patch

from jose import jwt

from app.auth.oauth_providers import GoogleOAuthProvider, OAuthUserInfo
from app.config.settings import settings
from tests.conftest import auth_header, TEST_USER_IDS


# ── TestRegister ──────────────────────────────────────────────────────


class TestRegister:
    """POST /api/v1/auth/register"""

    def test_register_success(self, client) -> None:
        resp = client.post(
            "/api/v1/auth/register",
            json={"email": "new@example.com", "password": "Str0ngP@ss!"},
        )
        assert resp.status_code == 201
        data = resp.json()
        assert "access_token" in data
        assert "refresh_token" in data
        assert "expires_at" in data
        # expires_at should be a future millisecond timestamp
        assert data["expires_at"] > int(time.time() * 1000)

    def test_register_returns_valid_jwt(self, client) -> None:
        resp = client.post(
            "/api/v1/auth/register",
            json={"email": "jwt-check@example.com", "password": "P@ss1234"},
        )
        assert resp.status_code == 201
        token = resp.json()["access_token"]
        payload = jwt.decode(token, settings.JWT_SECRET, algorithms=[settings.JWT_ALGORITHM])
        assert payload["email"] == "jwt-check@example.com"
        assert payload["tier"] == "free"
        assert "sub" in payload

    def test_register_duplicate_email(self, client) -> None:
        client.post(
            "/api/v1/auth/register",
            json={"email": "dupe@example.com", "password": "Pass1234"},
        )
        resp = client.post(
            "/api/v1/auth/register",
            json={"email": "dupe@example.com", "password": "Pass5678"},
        )
        assert resp.status_code == 409

    def test_register_missing_password(self, client) -> None:
        resp = client.post(
            "/api/v1/auth/register",
            json={"email": "no-pass@example.com"},
        )
        assert resp.status_code == 422

    def test_register_missing_email(self, client) -> None:
        resp = client.post(
            "/api/v1/auth/register",
            json={"password": "OnlyPass"},
        )
        assert resp.status_code == 422


# ── TestLogin ─────────────────────────────────────────────────────────


class TestLogin:
    """POST /api/v1/auth/login"""

    def _register(self, client, email="login@example.com", password="MyP@ss123"):
        client.post(
            "/api/v1/auth/register",
            json={"email": email, "password": password},
        )

    def test_login_success(self, client) -> None:
        self._register(client)
        resp = client.post(
            "/api/v1/auth/login",
            json={"email": "login@example.com", "password": "MyP@ss123"},
        )
        assert resp.status_code == 200
        data = resp.json()
        assert "access_token" in data
        assert "refresh_token" in data
        assert "expires_at" in data

    def test_login_wrong_password(self, client) -> None:
        self._register(client)
        resp = client.post(
            "/api/v1/auth/login",
            json={"email": "login@example.com", "password": "WrongPass!"},
        )
        assert resp.status_code == 401

    def test_login_unknown_email(self, client) -> None:
        resp = client.post(
            "/api/v1/auth/login",
            json={"email": "ghost@example.com", "password": "Whatever"},
        )
        assert resp.status_code == 401


# ── TestRefresh ───────────────────────────────────────────────────────


class TestRefresh:
    """POST /api/v1/auth/refresh"""

    def _register_and_get_tokens(self, client, email="refresh@example.com"):
        resp = client.post(
            "/api/v1/auth/register",
            json={"email": email, "password": "RefPass123!"},
        )
        return resp.json()

    def test_refresh_returns_new_tokens(self, client) -> None:
        tokens = self._register_and_get_tokens(client)
        resp = client.post(
            "/api/v1/auth/refresh",
            json={"refresh_token": tokens["refresh_token"]},
        )
        assert resp.status_code == 200
        data = resp.json()
        assert "access_token" in data
        assert "refresh_token" in data
        # New refresh token should differ from old one (rotation)
        assert data["refresh_token"] != tokens["refresh_token"]

    def test_refresh_old_token_rejected(self, client) -> None:
        """After rotation, the original refresh token must be rejected."""
        tokens = self._register_and_get_tokens(client, email="rotate@example.com")
        old_rt = tokens["refresh_token"]

        # First refresh succeeds and rotates the token
        client.post("/api/v1/auth/refresh", json={"refresh_token": old_rt})

        # Second attempt with the old token must fail
        resp = client.post("/api/v1/auth/refresh", json={"refresh_token": old_rt})
        assert resp.status_code == 401

    def test_refresh_bogus_token(self, client) -> None:
        resp = client.post(
            "/api/v1/auth/refresh",
            json={"refresh_token": "not-a-real-token"},
        )
        assert resp.status_code == 401


# ── TestMe ────────────────────────────────────────────────────────────


class TestMe:
    """GET /api/v1/auth/me"""

    def test_me_with_valid_jwt(self, client) -> None:
        resp = client.get("/api/v1/auth/me", headers=auth_header("power"))
        assert resp.status_code == 200
        data = resp.json()
        assert data["id"] == TEST_USER_IDS["power"]
        assert data["email"] == "power@test.com"
        assert data["tier"] == "power"

    def test_me_returns_correct_tier(self, client) -> None:
        """Tier comes from the live subscription row, not the JWT claim."""
        resp = client.get("/api/v1/auth/me", headers=auth_header("free"))
        assert resp.json()["tier"] == "free"

    def test_me_missing_token(self, client) -> None:
        resp = client.get("/api/v1/auth/me")
        assert resp.status_code == 401

    def test_me_expired_token(self, client) -> None:
        """A JWT with ``exp`` in the past must be rejected."""
        payload = {
            "sub": TEST_USER_IDS["power"],
            "email": "power@test.com",
            "tier": "power",
            "exp": int(time.time()) - 3600,  # 1 hour ago
            "iat": int(time.time()) - 7200,
        }
        token = jwt.encode(payload, settings.JWT_SECRET, algorithm=settings.JWT_ALGORITHM)
        resp = client.get("/api/v1/auth/me", headers={"Authorization": f"Bearer {token}"})
        assert resp.status_code == 401

    def test_me_invalid_signature(self, client) -> None:
        payload = {
            "sub": TEST_USER_IDS["power"],
            "email": "power@test.com",
            "tier": "power",
            "exp": int(time.time()) + 3600,
            "iat": int(time.time()),
        }
        token = jwt.encode(payload, "wrong-secret", algorithm="HS256")
        resp = client.get("/api/v1/auth/me", headers={"Authorization": f"Bearer {token}"})
        assert resp.status_code == 401


# ── TestOAuth ─────────────────────────────────────────────────────────


class TestOAuth:
    """GET /auth/oauth/google/authorize and POST /auth/oauth/google/callback."""

    FAKE_PROVIDER_USER_ID = "google-sub-12345"
    FAKE_EMAIL = "oauth@example.com"
    FAKE_AVATAR = "https://lh3.googleusercontent.com/photo.jpg"

    def _patch_google(self, monkeypatch) -> None:
        monkeypatch.setattr(settings, "GOOGLE_AUTH_CLIENT_ID", "fake-client-id")
        monkeypatch.setattr(settings, "GOOGLE_AUTH_CLIENT_SECRET", "fake-client-secret")

    def _userinfo(
        self,
        email: str | None = None,
        email_verified: bool = True,
    ) -> OAuthUserInfo:
        return OAuthUserInfo(
            provider_user_id=self.FAKE_PROVIDER_USER_ID,
            email=email or self.FAKE_EMAIL,
            email_verified=email_verified,
            avatar_url=self.FAKE_AVATAR,
            name="OAuth User",
        )

    def _authorize(self, client) -> str:
        """Call /authorize and return the fresh state token."""
        resp = client.get("/api/v1/auth/oauth/google/authorize")
        assert resp.status_code == 200
        return resp.json()["state"]

    def _callback(self, client, state: str, userinfo: OAuthUserInfo):
        """POST /callback with mocked provider exchange_code + get_userinfo."""
        with (
            patch.object(
                GoogleOAuthProvider,
                "exchange_code",
                new=AsyncMock(return_value={"access_token": "google-access-tok"}),
            ),
            patch.object(
                GoogleOAuthProvider,
                "get_userinfo",
                new=AsyncMock(return_value=userinfo),
            ),
        ):
            return client.post(
                "/api/v1/auth/oauth/google/callback",
                json={"code": "auth-code", "state": state},
            )

    def _decode_sub(self, access_token: str) -> str:
        return jwt.decode(
            access_token, settings.JWT_SECRET, algorithms=[settings.JWT_ALGORITHM]
        )["sub"]

    # -- authorize --

    def test_authorize_returns_url_and_state(self, client, monkeypatch) -> None:
        self._patch_google(monkeypatch)
        resp = client.get("/api/v1/auth/oauth/google/authorize")
        assert resp.status_code == 200
        data = resp.json()
        assert "url" in data and "state" in data
        assert "accounts.google.com" in data["url"]
        assert len(data["state"]) > 0

    def test_authorize_unconfigured_returns_503(self, client, monkeypatch) -> None:
        monkeypatch.setattr(settings, "GOOGLE_AUTH_CLIENT_ID", "")
        monkeypatch.setattr(settings, "GOOGLE_AUTH_CLIENT_SECRET", "")
        resp = client.get("/api/v1/auth/oauth/google/authorize")
        assert resp.status_code == 503

    # -- callback --

    def test_callback_state_mismatch_returns_401(self, client, monkeypatch) -> None:
        self._patch_google(monkeypatch)
        resp = client.post(
            "/api/v1/auth/oauth/google/callback",
            json={"code": "code", "state": "not-a-real-state"},
        )
        assert resp.status_code == 401

    def test_callback_creates_new_user(self, client, monkeypatch) -> None:
        """First-time Google login creates a new user and returns valid tokens."""
        self._patch_google(monkeypatch)
        state = self._authorize(client)
        resp = self._callback(client, state, self._userinfo())

        assert resp.status_code == 200
        data = resp.json()
        assert "access_token" in data and "refresh_token" in data
        payload = jwt.decode(
            data["access_token"], settings.JWT_SECRET, algorithms=[settings.JWT_ALGORITHM]
        )
        assert payload["email"] == self.FAKE_EMAIL

    def test_callback_existing_oauth_link_logs_in(self, client, monkeypatch) -> None:
        """Second Google login with the same account re-uses the existing user."""
        self._patch_google(monkeypatch)
        userinfo = self._userinfo()

        # First login — creates user + oauth_accounts row
        resp1 = self._callback(client, self._authorize(client), userinfo)
        assert resp1.status_code == 200
        sub1 = self._decode_sub(resp1.json()["access_token"])

        # Second login — finds existing oauth_accounts row → same user
        resp2 = self._callback(client, self._authorize(client), userinfo)
        assert resp2.status_code == 200
        sub2 = self._decode_sub(resp2.json()["access_token"])

        assert sub1 == sub2

    def test_callback_email_match_links_account(self, client, monkeypatch) -> None:
        """Verified Google email matching an existing password user links the accounts."""
        email = "link-target@example.com"
        reg_resp = client.post(
            "/api/v1/auth/register",
            json={"email": email, "password": "TestPass123!"},
        )
        assert reg_resp.status_code == 201
        orig_sub = self._decode_sub(reg_resp.json()["access_token"])

        self._patch_google(monkeypatch)
        state = self._authorize(client)
        resp = self._callback(client, state, self._userinfo(email=email, email_verified=True))

        assert resp.status_code == 200
        oauth_sub = self._decode_sub(resp.json()["access_token"])
        # OAuth login must resolve to the same user as the original registration
        assert orig_sub == oauth_sub

    def test_callback_unverified_email_conflict_returns_409(self, client, monkeypatch) -> None:
        """Unverified Google email matching an existing account returns 409, not 500."""
        email = "conflict@example.com"
        reg_resp = client.post(
            "/api/v1/auth/register",
            json={"email": email, "password": "TestPass123!"},
        )
        assert reg_resp.status_code == 201

        self._patch_google(monkeypatch)
        state = self._authorize(client)
        resp = self._callback(client, state, self._userinfo(email=email, email_verified=False))

        assert resp.status_code == 409