import uuid
from datetime import datetime, timedelta, timezone
from typing import Optional, List
from uuid import UUID, uuid4

import pytest
from fastapi import status

from app.api.routes.events.router import events_router
from app.models.event import Event
from app.models import EventManager
from app.models import User
from app.models.event_manager import EventManagerRole, ROLE_PERMISSIONS
from app.models import Guest


@pytest.fixture
def event_data():
    future_date = datetime.now(tz=timezone.utc) + timedelta(days=30)
    slug = f"test-event-{uuid4().hex[:8]}"
    return {
        "title": "Test Event",
        "slug": slug,
        "description": "Test description",
        "event_date": future_date.isoformat(),
        "timezone": "UTC",
        "is_public": True
    }


@pytest.fixture
def past_event_data():
    past_date = datetime.now(tz=timezone.utc) - timedelta(days=1)
    slug = f"past-event-{uuid4().hex[:8]}"
    return {
        "title": "Past Event",
        "slug": slug,
        "description": "This event date is in the past",
        "event_date": past_date.isoformat(),
        "timezone": "UTC",
        "is_public": True
    }


@pytest.fixture
def invalid_slug_event_data():
    future_date = datetime.now(tz=timezone.utc) + timedelta(days=30)
    return {
        "title": "Invalid Slug Event",
        "slug": "INVALID Slug!!",
        "description": "Event with invalid slug",
        "event_date": future_date.isoformat(),
        "timezone": "UTC",
        "is_public": True
    }


class TestCreateEvent:
    """Test scenarios for the create_event endpoint."""

    @pytest.fixture(autouse=True)
    def setup_method(self, create_test_client, db_session, mock_user):
        self.client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=mock_user
        )
        self.db_session = db_session
        self.mock_user = mock_user

    def test_create_event_success(self, db_session, mock_user, event_data):
        response = self.client.post("/events/", json=event_data)

        assert response.status_code == status.HTTP_201_CREATED, response.json()

        resp_json = response.json()
        assert resp_json["title"] == event_data["title"]
        assert resp_json["slug"] == event_data["slug"]

        event_id = UUID(resp_json["id"])
        db_event = db_session.query(Event).filter(Event.id == event_id).first()
        assert db_event is not None

    def test_create_event_missing_required_fields(self, db_session, mock_user):
        incomplete_data = {
            "title": "Incomplete Event"
            # Missing required fields like slug and event_date
        }

        response = self.client.post("/events/", json=incomplete_data)

        assert response.status_code == status.HTTP_422_UNPROCESSABLE_ENTITY

    def test_create_event_with_past_date_fails(self, db_session, mock_user, past_event_data):
        response = self.client.post("/events/", json=past_event_data)

        assert response.status_code == status.HTTP_422_UNPROCESSABLE_ENTITY, response.json()
        assert "Event date cannot be in the past" in response.text

    def test_create_event_invalid_slug_fails(self,  db_session, mock_user, invalid_slug_event_data):

        response = self.client.post("/events/", json=invalid_slug_event_data)

        assert response.status_code == status.HTTP_422_UNPROCESSABLE_ENTITY, response.json()
        assert "String should match pattern" in response.text

    def test_create_event_unauthorized_fails(self, create_test_client, db_session, event_data):
        client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=None
        )

        response = client.post("/events/", json=event_data)

        assert response.status_code == status.HTTP_401_UNAUTHORIZED, response.json()
        assert "Invalid authentication credentials" in response.text


class TestGetUserEvents:
    """Tests for the get_user_events endpoint."""

    @pytest.fixture(autouse=True)
    def setup_method(self, create_test_client, db_session, mock_user):
        self.client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=mock_user
        )
        self.db_session = db_session
        self.mock_user = mock_user

    def create_mock_events(self, num_events, active=True, public=True):
        """Utility function to create mock events in the database."""
        events = []
        for i in range(num_events):
            event_date = datetime.now(tz=timezone.utc) + timedelta(days=i + 1)
            mock_event = Event(
                id=uuid4(),
                title=f"Mock Event {i}",
                slug=f"mock-event-{uuid4().hex[:8]}",
                event_date=event_date,
                timezone="UTC",
                is_public=public,
                is_active=active,
                created_by=self.mock_user.id,
                created_at=datetime.now(tz=timezone.utc),
                updated_at=datetime.now(tz=timezone.utc),
            )
            self.db_session.add(mock_event)
            events.append(mock_event)
        self.db_session.commit()
        return events

    def test_get_user_events_success(self):
        """User gets their events correctly."""
        created_events = self.create_mock_events(3)

        response = self.client.get("/events/me")

        assert response.status_code == status.HTTP_200_OK, response.json()

        data = response.json()
        assert "items" in data
        assert len(data["items"]) == 3
        returned_titles = {event["title"] for event in data["items"]}
        assert all(event.title in returned_titles for event in created_events)

    def test_get_user_events_pagination(self):
        """User events are returned paginated."""
        self.create_mock_events(10)

        response = self.client.get("/events/me?skip=5&limit=3")

        assert response.status_code == status.HTTP_200_OK, response.json()

        data = response.json()
        assert len(data["items"]) == 3
        assert data["total"] == 10

    def test_get_user_events_include_inactive(self):
        """Inactive events should be included if requested explicitly."""
        # Create active and inactive events
        self.create_mock_events(2, active=False)
        self.create_mock_events(1, active=True)

        response_default = self.client.get("/events/me")
        data_default = response_default.json()
        assert response_default.status_code == status.HTTP_200_OK
        assert len(data_default["items"]) == 1  # Active included only by default

        response_include_inactive = self.client.get("/events/me?include_inactive=true")
        data_inactive = response_include_inactive.json()
        assert response_include_inactive.status_code == status.HTTP_200_OK
        assert len(data_inactive["items"]) == 3  # Inactive explicitly included

    def test_get_user_events_unauthenticated_fails(self, create_test_client):
        """Endpoint must not allow access without authentication."""
        unauth_client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=self.db_session,
            user=None
        )

        response = unauth_client.get("/events/me")

        assert response.status_code == status.HTTP_401_UNAUTHORIZED, response.json()
        assert "Invalid authentication credentials" in response.text

    def test_get_user_events_no_events(self):
        """User without events should receive an empty list."""
        response = self.client.get("/events/me")

        assert response.status_code == status.HTTP_200_OK, response.json()

        data = response.json()
        assert "items" in data
        assert data["items"] == []
        assert data["total"] == 0


class TestGetUpcomingEvents:
    """Tests for the get_upcoming_events endpoint."""

    @pytest.fixture(autouse=True)
    def setup_method(self, create_test_client, db_session, mock_user):
        self.client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=mock_user
        )
        self.db_session = db_session
        self.mock_user = mock_user

    def create_mock_event(self, days_from_now: int, is_active=True, is_public=True):
        """Utility method for creating mocked event data in database."""
        event = Event(
            id=uuid4(),
            title=f"Upcoming Event {uuid4().hex[:4]}",
            slug=f"upcoming-event-{uuid4().hex[:8]}",
            description="Upcoming event description",
            event_date=datetime.now(tz=timezone.utc) + timedelta(days=days_from_now),
            timezone="UTC",
            is_public=is_public,
            is_active=is_active,
            created_by=self.mock_user.id,
            created_at=datetime.now(timezone.utc),
            updated_at=datetime.now(timezone.utc),
        )
        self.db_session.add(event)
        self.db_session.commit()
        return event

    def test_get_upcoming_events_success_default_limit(self):
        """Ensure upcoming events are retrieved according to default limit."""
        for i in range(15):
            self.create_mock_event(days_from_now=i + 1)

        response = self.client.get("/events/upcoming")

        assert response.status_code == status.HTTP_200_OK, response.json()

        data = response.json()
        assert "items" in data  # asserting structure explicitly
        assert len(data["items"]) == 15  # explicitly checking items list length
        assert data["total"] == 15  # check total is correct
        assert data["size"] == 100  # default size


    def test_get_upcoming_events_with_query_limit(self):
        """Verifies the limit parameter works correctly."""
        # create 5 events
        for i in range(5):
            self.create_mock_event(days_from_now=i + 1)

        response = self.client.get("/events/upcoming?limit=3")

        assert response.status_code == status.HTTP_200_OK, response.json()

        data = response.json()
        assert "items" in data  # asserting structure explicitly
        assert len(data["items"]) == 3
        assert data["total"] == 5
        assert data["size"] == 3

    def test_get_upcoming_events_only_active_and_future_events_returned(self):
        """Ensure only future active events are returned."""
        # Past events and inactive events shouldn't be returned
        self.create_mock_event(days_from_now=-5)  # past event
        self.create_mock_event(days_from_now=3, is_active=False)  # inactive event
        valid_event = self.create_mock_event(days_from_now=5)  # active future event

        response = self.client.get("/events/upcoming")

        assert response.status_code == status.HTTP_200_OK, response.json()

        data = response.json()
        assert len(data["items"]) == 1
        assert data["items"][0]["slug"] == valid_event.slug

    def test_get_upcoming_events_unauthenticated_fails(self, create_test_client, db_session):
        """Verify unauthorized users cannot access this endpoint."""
        client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=None,
        )

        response = client.get("/events/upcoming")

        assert response.status_code == status.HTTP_401_UNAUTHORIZED, response.json()
        assert "Invalid authentication credentials" in response.text

    def test_get_upcoming_events_no_events_available(self):
        """Check the response if no upcoming events exist."""
        response = self.client.get("/events/upcoming")

        assert response.status_code == status.HTTP_200_OK, response.json()

        data = response.json()
        assert isinstance(data["items"], list) and len(data["items"]) == 0

class TestGetPublicEvents:
    @pytest.fixture(autouse=True)
    def setup_method(self, create_test_client, db_session, mock_user):
        self.client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=mock_user
        )
        self.db_session = db_session
        self.mock_user = mock_user

    def create_mock_event(self, days_from_now: int, is_public=True, is_active=True):
        event = Event(
            id=uuid4(),
            title=f"Event {uuid4().hex[:4]}",
            slug=f"event-{uuid4().hex[:8]}",
            description="Event description",
            event_date=datetime.now(tz=timezone.utc) + timedelta(days=days_from_now),
            timezone="UTC",
            is_public=is_public,
            is_active=is_active,
            created_by=self.mock_user.id,
            created_at=datetime.now(timezone.utc),
            updated_at=datetime.now(timezone.utc),
        )
        self.db_session.add(event)
        self.db_session.commit()
        return event

    def test_public_events_success_default_limit(self):
        """Return default limit 100 public events"""
        for i in range(120):
            self.create_mock_event(days_from_now=i + 1, is_public=True)

        response = self.client.get("/events/public")
        assert response.status_code == status.HTTP_200_OK

        data = response.json()
        assert len(data["items"]) == 100  # default limit
        assert data["total"] == 120
        assert data["page"] == 1
        assert data["size"] == 100

    def test_public_events_pagination(self):
        """Return paginated events"""
        for i in range(30):
            self.create_mock_event(days_from_now=i + 1, is_public=True)

        response = self.client.get("/events/public?skip=10&limit=5")
        assert response.status_code == status.HTTP_200_OK

        data = response.json()
        assert len(data["items"]) == 5
        assert data["total"] == 30
        assert data["page"] == 3  # skip=10, limit=5 means page=3
        assert data["size"] == 5

    def test_non_public_events_never_returned(self):
        """Ensure events marked is_public=False aren't retrieved"""
        for i in range(10):
            self.create_mock_event(days_from_now=i + 1, is_public=False)

        for i in range(5):
            self.create_mock_event(days_from_now=i + 1, is_public=True)

        response = self.client.get("/events/public")
        assert response.status_code == status.HTTP_200_OK

        data = response.json()
        assert len(data["items"]) == 5  # only public events returned
        assert data["total"] == 5

    def test_public_events_no_events_available(self):
        """Edge case: when no public events in db"""
        response = self.client.get("/events/public")
        assert response.status_code == status.HTTP_200_OK

        data = response.json()
        assert len(data["items"]) == 0
        assert data["total"] == 0
        assert data["page"] == 1
        assert data["size"] == 100

# @pytest.mark.parametrize("endpoint_type", ["id", "slug"])
@pytest.mark.parametrize("endpoint_type", ["id"])
class TestGetEvent:
    @pytest.fixture(autouse=True)
    def setup_method(self, create_test_client, db_session, mock_user, endpoint_type):
        self.client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=mock_user
        )
        self.db_session = db_session
        self.mock_user = mock_user
        self.endpoint_type = endpoint_type


    def create_mock_user(
            self,
            email="testuser@example.com",
            is_superuser=False,
            is_active=True
    ):
        user = User(
            id=uuid.uuid4(),
            email=email,
            password_hash="mockhashedpassword",
            first_name="Test",
            last_name="User",
            phone_number="1234567890",
            is_active=is_active,
            is_superuser=is_superuser,
            preferences=None,
        )
        self.db_session.add(user)
        self.db_session.commit()
        return user

    def create_mock_event(
            self,
            created_by: UUID,
            title: str = "Test Event",
            slug: str = "test-event",
            description: str = "A sample event for testing purposes.",
            event_date: Optional[datetime] = None,
            timezone_str: str = "UTC",
            is_public: bool = False,
            is_active: bool = True,
            managers: Optional[List] = None,
            manager_role: EventManagerRole = EventManagerRole.ADMIN,
    ):
        if event_date is None:
            event_date = datetime.now(timezone.utc) + timedelta(days=10)  # Default to 10 days in future if not specified

        # Create Event instance
        mock_event = Event(
            title=title,
            slug=slug,
            description=description,
            event_date=event_date,
            timezone=timezone_str,
            created_by=created_by,
            is_public=is_public,
            is_active=is_active,
            rsvp_enabled=True,
            gift_registry_enabled=True,
            updates_enabled=True,
        )

        self.db_session.add(mock_event)
        self.db_session.flush()  # Use flush here to get a valid event_id before assigning managers

        # If managers are provided, set EventManager instances
        if managers:
            for manager in managers:
                role_permissions = ROLE_PERMISSIONS.get(manager_role, {})
                event_manager = EventManager(
                    user_id=manager.id,
                    event_id=mock_event.id,
                    assigned_by=created_by,
                    role=manager_role,
                    can_edit=role_permissions.get("can_edit", False),
                    can_invite=role_permissions.get("can_invite", False),
                    can_manage_gifts=role_permissions.get("can_manage_gifts", False),
                    can_send_updates=role_permissions.get("can_send_updates", False),
                    can_view_analytics=role_permissions.get("can_view_analytics", False),
                    assigned_at=datetime.now(timezone.utc),
                )
                self.db_session.add(event_manager)

        # persist the changes
        self.db_session.commit()
        self.db_session.refresh(mock_event)

        return mock_event

    def get_event_endpoint(self, event_obj, access_code=None):
        """
        Helper method to dynamically build the endpoint URL based on the test parameter.
        """
        if self.endpoint_type == "id":
            endpoint = f"/events/{event_obj.id}"
        # else:
        #     endpoint = f"/events/by-slug/{event_obj.slug}"
        if access_code is not None:
            endpoint += f"?access_code={access_code}"
        return endpoint

    def test_get_event_by_creator_success(self):
        mocked_event = self.create_mock_event(created_by=self.mock_user.id)

        endpoint = self.get_event_endpoint(mocked_event)
        response = self.client.get(endpoint)

        assert response.status_code == status.HTTP_200_OK
        assert response.json()["id"] == str(mocked_event.id)


    # def test_get_event_by_creator_success(self):
    #     mocked_event = self.create_mock_event(created_by=self.mock_user.id)
    #
    #     response = self.client.get(f"/events/{mocked_event.id}")
    #
    #     assert response.status_code == status.HTTP_200_OK
    #     assert response.json()["id"] == str(mocked_event.id)

    def test_get_event_by_manager_success(self, mock_user):
        manager_user = self.create_mock_user(email="manager@example.com")
        mocked_event = self.create_mock_event(created_by=self.mock_user.id, managers=[manager_user])

        self.client.user = manager_user

        response = self.client.get(f"/events/{mocked_event.id}")

        assert response.status_code == status.HTTP_200_OK
        assert response.json()["id"] == str(mocked_event.id)

    def test_get_event_by_superuser_success(self):
        superuser = self.create_mock_user(email="superuser@example.com", is_superuser=True)

        mocked_event = self.create_mock_event(created_by=self.mock_user.id)

        self.client.user = superuser

        response = self.client.get(f"/events/{mocked_event.id}")

        assert response.status_code == status.HTTP_200_OK
        assert response.json()["id"] == str(mocked_event.id)


        def test_get_event_not_exists(self):
            random_event_id = uuid4()

            response = self.client.get(f"/events/{random_event_id}")

            assert response.status_code == status.HTTP_404_NOT_FOUND
            assert response.json()["detail"] == "Event not found"

    def test_get_public_event_by_non_related_user_success(self):
        other_user = self.create_mock_user(email="randomuser@example.com")

        mocked_event = self.create_mock_event(
            created_by=self.mock_user.id,
            is_public=True
        )

        self.client.user = other_user

        response = self.client.get(f"/events/{mocked_event.id}")

        assert response.status_code == status.HTTP_200_OK
        assert response.json()["id"] == str(mocked_event.id)


    def test_get_private_event_by_guest_user_success(self):
        guest_user = self.create_mock_user(email="guestuser@example.com")

        mocked_event = self.create_mock_event(
            created_by=self.mock_user.id,
            is_public=False
        )

        guest_entry = Guest(
            full_name="Guest User",
            invitation_code="0000",
            user_id=guest_user.id,
            event_id=mocked_event.id,
            invited_by=self.mock_user.id,
        )
        self.db_session.add(guest_entry)
        self.db_session.commit()

        self.client.user = guest_user

        response = self.client.get(f"/events/{mocked_event.id}")

        assert response.status_code == status.HTTP_200_OK
        assert response.json()["id"] == str(mocked_event.id)


    def test_get_private_event_non_related_user_forbidden(self):
        creator_user = self.create_mock_user(email="creator@example.com")
        other_user = self.create_mock_user(email="nonrelated@example.com", is_superuser=False)

        mocked_event = self.create_mock_event(
            created_by=creator_user.id,
            is_public=False
        )

        self.client.user = other_user

        response = self.client.get(f"/events/{mocked_event.id}")

        assert response.status_code == status.HTTP_403_FORBIDDEN
        assert response.json()["detail"] == "Not enough permissions to access this event"


    def test_get_event_unauthenticated_user_fails(self, create_test_client, db_session):
        mocked_event = self.create_mock_event(
            created_by=self.mock_user.id,
            is_public=False
        )
        client = create_test_client(
            router=events_router,
            prefix="/events",
            db_session=db_session,
            user=None,
        )

        self.client.user = None  # Simulate no authenticated user

        response = client.get(f"/events/{mocked_event.id}")

        assert response.status_code == status.HTTP_403_FORBIDDEN
        assert response.json()["detail"] == "Not enough permissions to access this event"