"""Application-level, multi-user acceptance tests for the full MyWhoosh -> Garmin
sync pipeline (Task 7 of the sync-scheduler-web plan).

These tests build a real `SyncManager` wired to a real SQLite database and a
real `CredentialCipher`, but with fake MyWhoosh/Garmin factories, so they
exercise the whole state machine end-to-end for two independent users without
touching any real external service.
"""

from __future__ import annotations

from pathlib import Path

import pytest
from cryptography.fernet import Fernet
from sqlalchemy import func, select
from sqlalchemy.orm import sessionmaker

from app.db.models import Activity, ActivityStatus, HealthState, SyncUser
from app.db.repositories import UserRepository
from app.db.session import create_db_engine, create_session_factory, initialize_schema
from app.garmin.uploader import GarminUploadBlocked, UploadResult
from app.mywhoosh.models import MyWhooshActivity
from app.security.credentials import CredentialCipher
from app.sync.manager import SyncManager


class StubSettings:
    """Minimal stand-in for app.config.Settings exposing only the two
    properties SyncManager needs."""

    def __init__(self, tmp_path: Path) -> None:
        self.tokens_dir = tmp_path / "tokens"
        self.activities_dir = tmp_path / "activities"


class FakeMyWhooshClient:
    def __init__(self, activities, fit_bytes: bytes) -> None:
        self.activities = activities
        self.fit_bytes = fit_bytes
        self.list_calls = 0
        self.download_calls = 0

    async def list_activities(self, email, password):
        self.list_calls += 1
        return list(self.activities)

    async def download_fit(self, activity_file_id, email, password):
        self.download_calls += 1
        return self.fit_bytes


class FakeGarminUploader:
    def __init__(self, result: UploadResult | None = None, error: Exception | None = None) -> None:
        self.result = result or UploadResult("imported", False, "g-1", {"activityId": "g-1"})
        self.error = error
        self.calls = 0

    def import_fit(self, fit_path, mfa_code=None):
        self.calls += 1
        if self.error is not None:
            raise self.error
        return self.result


def fake_fit_converter(source_path: Path, output_path: Path) -> None:
    output_path.parent.mkdir(parents=True, exist_ok=True)
    output_path.write_bytes(b"fake-converted-fit-bytes")


def count_terminal_activities(session_factory: sessionmaker, user_id: int) -> int:
    with session_factory() as session:
        return session.scalar(
            select(func.count())
            .select_from(Activity)
            .where(
                Activity.user_id == user_id,
                Activity.status.in_([ActivityStatus.IMPORTED, ActivityStatus.DUPLICATE]),
            )
        )


def _create_user(session, cipher: CredentialCipher, *, name: str) -> SyncUser:
    return UserRepository(session).create(
        name=name,
        enabled=True,
        mywhoosh_email_enc=cipher.encrypt(f"{name.lower()}-mywhoosh@example.com"),
        mywhoosh_password_enc=cipher.encrypt("mw-secret"),
        garmin_email_enc=cipher.encrypt(f"{name.lower()}-garmin@example.com"),
        garmin_password_enc=cipher.encrypt("garmin-secret"),
    )


@pytest.fixture
def session_factory(tmp_path: Path):
    db_path = tmp_path / "acceptance.db"
    engine = create_db_engine(f"sqlite:///{db_path}")
    initialize_schema(engine)
    factory = create_session_factory(engine)
    try:
        yield factory
    finally:
        engine.dispose()


@pytest.fixture
def cipher() -> CredentialCipher:
    return CredentialCipher(Fernet.generate_key().decode("ascii"))


@pytest.fixture
def settings(tmp_path: Path) -> StubSettings:
    return StubSettings(tmp_path)


@pytest.fixture
def two_users(session_factory, cipher: CredentialCipher):
    with session_factory() as session:
        user_a = _create_user(session, cipher, name="Alice")
        user_b = _create_user(session, cipher, name="Bob")
        return user_a, user_b


def _build_manager(
    *,
    session_factory,
    cipher: CredentialCipher,
    settings: StubSettings,
    user_a: SyncUser,
    user_b: SyncUser,
    fake_mw_a: FakeMyWhooshClient,
    fake_mw_b: FakeMyWhooshClient,
    fake_garmin_a: FakeGarminUploader,
    fake_garmin_b: FakeGarminUploader,
):
    mywhoosh_fakes = {str(user_a.id): fake_mw_a, str(user_b.id): fake_mw_b}
    garmin_fakes = {str(user_a.id): fake_garmin_a, str(user_b.id): fake_garmin_b}
    garmin_factory_calls: list[tuple[str, str, Path]] = []

    def mywhoosh_factory(token_store):
        user_key = token_store.path.parent.name
        return mywhoosh_fakes[user_key]

    def garmin_factory(email, password, tokenstore):
        garmin_factory_calls.append((email, password, tokenstore))
        user_key = tokenstore.parent.name
        return garmin_fakes[user_key]

    manager = SyncManager(
        session_factory=session_factory,
        credential_cipher=cipher,
        settings=settings,
        mywhoosh_factory=mywhoosh_factory,
        garmin_factory=garmin_factory,
        fit_converter=fake_fit_converter,
    )
    return manager, garmin_factory_calls


@pytest.mark.asyncio
async def test_two_user_happy_path(session_factory, cipher, settings, two_users):
    user_a, user_b = two_users

    remote_a = MyWhooshActivity(
        id="remote-a-1", title="Alice Ride", activity_file_id="file-a-1", started_at=None
    )
    remote_b = MyWhooshActivity(
        id="remote-b-1", title="Bob Ride", activity_file_id="file-b-1", started_at=None
    )
    fake_mw_a = FakeMyWhooshClient(activities=[remote_a], fit_bytes=b"alice-source-bytes")
    fake_mw_b = FakeMyWhooshClient(activities=[remote_b], fit_bytes=b"bob-source-bytes")
    fake_garmin_a = FakeGarminUploader()
    fake_garmin_b = FakeGarminUploader()

    manager, garmin_factory_calls = _build_manager(
        session_factory=session_factory,
        cipher=cipher,
        settings=settings,
        user_a=user_a,
        user_b=user_b,
        fake_mw_a=fake_mw_a,
        fake_mw_b=fake_mw_b,
        fake_garmin_a=fake_garmin_a,
        fake_garmin_b=fake_garmin_b,
    )

    results = await manager.sync_all_enabled()

    assert all(result.status == "success" for result in results)
    assert count_terminal_activities(session_factory, user_a.id) == 1
    assert count_terminal_activities(session_factory, user_b.id) == 1

    with session_factory() as session:
        activity_a = session.scalar(select(Activity).where(Activity.user_id == user_a.id))
        activity_b = session.scalar(select(Activity).where(Activity.user_id == user_b.id))
        assert Path(activity_a.source_fit_path).exists()
        assert Path(activity_b.source_fit_path).exists()
        assert Path(activity_a.source_fit_path).parent != Path(activity_b.source_fit_path).parent

    tokenstores = {str(call[2]) for call in garmin_factory_calls}
    assert len(tokenstores) == 2

    # Idempotency (spec 26.8): re-running sync_all_enabled with no new remote
    # activities must not re-download/re-convert/re-import anything, and must
    # not create a second terminal Activity row for the same MyWhoosh activity.
    download_calls_a_before = fake_mw_a.download_calls
    download_calls_b_before = fake_mw_b.download_calls
    garmin_calls_a_before = fake_garmin_a.calls
    garmin_calls_b_before = fake_garmin_b.calls

    second_results = await manager.sync_all_enabled()

    assert all(result.status == "success" for result in second_results)
    assert fake_mw_a.download_calls == download_calls_a_before
    assert fake_mw_b.download_calls == download_calls_b_before
    assert fake_garmin_a.calls == garmin_calls_a_before
    assert fake_garmin_b.calls == garmin_calls_b_before
    assert count_terminal_activities(session_factory, user_a.id) == 1
    assert count_terminal_activities(session_factory, user_b.id) == 1


@pytest.mark.asyncio
async def test_isolation_when_one_user_requires_mfa(session_factory, cipher, settings, two_users):
    user_a, user_b = two_users

    remote_a = MyWhooshActivity(
        id="remote-a-1", title="Alice Ride", activity_file_id="file-a-1", started_at=None
    )
    remote_b = MyWhooshActivity(
        id="remote-b-1", title="Bob Ride", activity_file_id="file-b-1", started_at=None
    )
    fake_mw_a = FakeMyWhooshClient(activities=[remote_a], fit_bytes=b"alice-source-bytes")
    fake_mw_b = FakeMyWhooshClient(activities=[remote_b], fit_bytes=b"bob-source-bytes")
    fake_garmin_a = FakeGarminUploader()
    fake_garmin_b = FakeGarminUploader(error=GarminUploadBlocked("Garmin requested MFA"))

    manager, garmin_factory_calls = _build_manager(
        session_factory=session_factory,
        cipher=cipher,
        settings=settings,
        user_a=user_a,
        user_b=user_b,
        fake_mw_a=fake_mw_a,
        fake_mw_b=fake_mw_b,
        fake_garmin_a=fake_garmin_a,
        fake_garmin_b=fake_garmin_b,
    )

    results = await manager.sync_all_enabled()

    results_by_user = {result.user_id: result for result in results}
    assert results_by_user[user_a.id].status == "success"
    assert results_by_user[user_b.id].status != "success"
    assert results_by_user[user_b.id].status == "failed"

    assert count_terminal_activities(session_factory, user_a.id) == 1

    with session_factory() as session:
        reloaded_b = UserRepository(session).get(user_b.id)
        assert reloaded_b.health_state == HealthState.ACTION_REQUIRED
        assert reloaded_b.action_reason == "garmin_mfa_required"

        reloaded_a = UserRepository(session).get(user_a.id)
        assert reloaded_a.health_state == HealthState.HEALTHY
        assert reloaded_a.action_reason is None

        activity_a = session.scalar(select(Activity).where(Activity.user_id == user_a.id))
        assert activity_a.status in (ActivityStatus.IMPORTED, ActivityStatus.DUPLICATE)