from argon2 import PasswordHasher
from httpx import AsyncClient

from porchlight.authn.password import PasswordService
from porchlight.invite.service import MagicLinkService
from porchlight.models import PasswordCredential, User
from tests.conftest import get_csrf_token


async def test_register_invalid_token_returns_error_page(client: AsyncClient) -> None:
    res = await client.get("/register/nope", follow_redirects=False)
    assert res.status_code == 400
    assert "Invalid or expired" in res.text


async def test_register_expired_token_returns_error_page(client: AsyncClient) -> None:
    app = client._transport.app  # type: ignore[union-attr]
    # An already-expired link (negative TTL), stored hashed like the real service.
    expired_service = MagicLinkService(repo=app.state.magic_link_repo, ttl=-3600)
    link = await expired_service.create(username="newuser")

    res = await client.get(f"/register/{link.token}", follow_redirects=False)
    assert res.status_code == 400
    assert "Invalid or expired" in res.text


async def test_register_get_does_not_consume_token(client: AsyncClient) -> None:
    """GET is side-effect free: it shows a confirmation form and must not
    consume the token or create a session."""
    app = client._transport.app  # type: ignore[union-attr]
    magic_link_service = app.state.magic_link_service

    link = await magic_link_service.create(username="newuser")
    res = await client.get(f"/register/{link.token}", follow_redirects=False)
    assert res.status_code == 200
    assert f'action="/register/{link.token}"' in res.text
    # Token still valid (not consumed by the GET).
    assert await magic_link_service.validate(link.token) is not None


async def test_register_post_creates_user_and_redirects(client: AsyncClient) -> None:
    app = client._transport.app  # type: ignore[union-attr]
    magic_link_service = app.state.magic_link_service
    user_repo = app.state.user_repo

    link = await magic_link_service.create(username="newuser")

    csrf = await get_csrf_token(client)
    res = await client.post(
        f"/register/{link.token}",
        headers={"X-CSRF-Token": csrf},
        follow_redirects=False,
    )
    assert res.status_code in (302, 303)
    assert "/manage/credentials" in res.headers["location"]
    assert "setup=1" in res.headers["location"]

    # Token should be consumed (no longer valid)
    assert await magic_link_service.validate(link.token) is None

    # User should exist
    user = await user_repo.get_by_username("newuser")
    assert user is not None
    assert "users" in user.groups


async def test_register_post_requires_csrf(client: AsyncClient) -> None:
    app = client._transport.app  # type: ignore[union-attr]
    magic_link_service = app.state.magic_link_service
    link = await magic_link_service.create(username="newuser")

    res = await client.post(f"/register/{link.token}", follow_redirects=False)
    assert res.status_code == 403
    # Token must not have been consumed by the rejected request.
    assert await magic_link_service.validate(link.token) is not None


async def test_register_used_token_returns_error(client: AsyncClient) -> None:
    app = client._transport.app  # type: ignore[union-attr]
    magic_link_service = app.state.magic_link_service
    link = await magic_link_service.create(username="newuser")
    await magic_link_service.mark_used(link.token)

    res = await client.get(f"/register/{link.token}", follow_redirects=False)
    assert res.status_code == 400


async def test_register_existing_user_logs_in_and_redirects(client: AsyncClient) -> None:
    """When initial-admin creates a user (no credentials yet), the invite link
    should let them set up their account."""
    app = client._transport.app  # type: ignore[union-attr]
    magic_link_service = app.state.magic_link_service
    user_repo = app.state.user_repo

    # Pre-create the user (as initial-admin would), with no credentials.
    user = User(userid="lusab-bansen", username="admin", groups=["admin", "users"])
    await user_repo.create(user)

    link = await magic_link_service.create(username="admin")

    csrf = await get_csrf_token(client)
    res = await client.post(
        f"/register/{link.token}",
        headers={"X-CSRF-Token": csrf},
        follow_redirects=False,
    )
    assert res.status_code in (302, 303)
    assert "/manage/credentials" in res.headers["location"]
    assert "setup=1" in res.headers["location"]

    # Token should be consumed
    assert await magic_link_service.validate(link.token) is None

    # Original user should still exist with original groups
    existing = await user_repo.get_by_username("admin")
    assert existing is not None
    assert existing.userid == "lusab-bansen"
    assert "admin" in existing.groups


async def test_register_rejects_user_that_already_has_credentials(client: AsyncClient) -> None:
    """An invite/re-invite link must not act as a passwordless login for an
    account that already has credentials. Recovery is a separate flow."""
    app = client._transport.app  # type: ignore[union-attr]
    magic_link_service = app.state.magic_link_service
    user_repo = app.state.user_repo
    cred_repo = app.state.credential_repo

    user = User(userid="lusab-hascreds", username="hascreds", groups=["users"])
    await user_repo.create(user)
    svc = PasswordService(hasher=PasswordHasher(time_cost=1, memory_cost=8192))
    await cred_repo.create_password(PasswordCredential(user_id=user.userid, password_hash=svc.hash("existing-pass")))

    link = await magic_link_service.create(username="hascreds")
    csrf = await get_csrf_token(client)
    res = await client.post(
        f"/register/{link.token}",
        headers={"X-CSRF-Token": csrf},
        follow_redirects=False,
    )

    # No passwordless login: rejected, not redirected to setup.
    assert res.status_code == 400
    assert "setup=1" not in res.headers.get("location", "")