import pytest
from django.urls import reverse
from django.contrib.auth import get_user_model
from atlas.models import Case, MultiuserSession
from pytest_django.asserts import assertContains, assertRedirects

@pytest.mark.django_db
def test_multiuser_session_model_creation(create_user):
    user = create_user
    session = MultiuserSession.objects.create(
        name="Test Sync Session",
        creator=user
    )
    assert session.name == "Test Sync Session"
    assert session.creator == user
    assert session.active_case is None
    assert str(session).startswith("Session Test Sync")

@pytest.mark.django_db
def test_multiuser_dashboard_view_anonymous_redirect(client):
    response = client.get(reverse("atlas:multiuser_dashboard"))
    assertRedirects(response, f"{reverse('login')}?next={reverse('atlas:multiuser_dashboard')}")

@pytest.mark.django_db
def test_multiuser_dashboard_lists_sessions_staff(client, create_user):
    user = create_user
    user.is_staff = True
    user.save()
    session1 = MultiuserSession.objects.create(name="User Session 1", creator=user)
    
    User = get_user_model()
    other_user = User.objects.create_user(username="other", password="password", email="other@test.com")
    session2 = MultiuserSession.objects.create(name="Other Session 2", creator=other_user)
    
    client.force_login(user)
    response = client.get(reverse("atlas:multiuser_dashboard"))
    assert response.status_code == 200
    assertContains(response, "User Session 1")
    assertContains(response, "Other Session 2")
    assertContains(response, "Start New Session")

@pytest.mark.django_db
def test_multiuser_dashboard_lists_sessions_non_staff(client, create_user):
    user = create_user
    
    User = get_user_model()
    other_user = User.objects.create_user(username="other", password="password", email="other@test.com")
    other_user.is_staff = True
    other_user.save()
    session2 = MultiuserSession.objects.create(name="Other Session 2", creator=other_user)
    
    client.force_login(user)
    response = client.get(reverse("atlas:multiuser_dashboard"))
    assert response.status_code == 200
    assertContains(response, "Other Session 2")
    assert "Start New Session" not in response.content.decode("utf-8")
    assert "Sessions You Managed" not in response.content.decode("utf-8")

@pytest.mark.django_db
def test_multiuser_create_session_action(client, create_user):
    user = create_user
    user.is_staff = True
    user.save()
    client.force_login(user)
    response = client.post(reverse("atlas:multiuser_create_session"), data={"name": "My New Session"})
    
    session = MultiuserSession.objects.get(name="My New Session")
    assertRedirects(response, reverse("atlas:multiuser_session_detail", kwargs={"session_id": session.id}))

@pytest.mark.django_db
def test_multiuser_create_session_action_non_staff_denied(client, create_user):
    user = create_user
    client.force_login(user)
    response = client.post(reverse("atlas:multiuser_create_session"), data={"name": "Denied Session"})
    assert response.status_code == 302 # Redirected to admin login page because of @staff_member_required

@pytest.mark.django_db
def test_multiuser_session_detail_manager_vs_participant(client):
    User = get_user_model()
    manager = User.objects.create_user(username="manager", password="password", email="manager@test.com")
    participant = User.objects.create_user(username="participant", password="password", email="participant@test.com")
    session = MultiuserSession.objects.create(name="Collaboration Session", creator=manager)
    
    # Manager view
    client.force_login(manager)
    response = client.get(reverse("atlas:multiuser_session_detail", kwargs={"session_id": session.id}))
    assert response.status_code == 200
    assertContains(response, "Host Controls:")
    assertContains(response, "Search cases to load...")
    
    # Participant view
    client.force_login(participant)
    response = client.get(reverse("atlas:multiuser_session_detail", kwargs={"session_id": session.id}))
    assert response.status_code == 200
    assert "Host Controls:" not in response.content.decode("utf-8")
    assertContains(response, "You are viewing this session in real-time")

@pytest.mark.django_db
def test_multiuser_search_cases_permission(client):
    User = get_user_model()
    manager = User.objects.create_user(username="manager", password="password", email="manager@test.com")
    participant = User.objects.create_user(username="participant", password="password", email="participant@test.com")
    session = MultiuserSession.objects.create(name="Search Session", creator=manager)
    
    # Participant cannot search
    client.force_login(participant)
    response = client.get(reverse("atlas:multiuser_search_cases", kwargs={"session_id": session.id}) + "?q=test")
    assert response.status_code == 403
    
    # Manager can search
    client.force_login(manager)
    response = client.get(reverse("atlas:multiuser_search_cases", kwargs={"session_id": session.id}) + "?q=test")
    assert response.status_code == 200

@pytest.mark.django_db
def test_multiuser_load_case_action(client, make_case):
    User = get_user_model()
    manager = User.objects.create_user(username="manager", password="password", email="manager@test.com")
    participant = User.objects.create_user(username="participant", password="password", email="participant@test.com")
    session = MultiuserSession.objects.create(name="Load Case Session", creator=manager)
    
    case = make_case(title="Multiuser Dicom Case")
    case.author.add(manager) # Grant access to manager
    
    # Participant cannot load
    client.force_login(participant)
    response = client.post(reverse("atlas:multiuser_load_case", kwargs={"session_id": session.id}), data={"case_id": case.pk})
    assert response.status_code == 403
    
    # Manager loads case
    client.force_login(manager)
    from unittest.mock import patch, MagicMock, AsyncMock
    with patch("channels.layers.get_channel_layer") as mock_get_channel_layer:
        mock_layer = MagicMock()
        mock_layer.group_send = AsyncMock()
        mock_get_channel_layer.return_value = mock_layer
        
        response = client.post(reverse("atlas:multiuser_load_case", kwargs={"session_id": session.id}), data={"case_id": case.pk})
        assert response.status_code == 200
        
        # Verify Channels group_send was called to notify the group about the case change
        mock_layer.group_send.assert_called_once_with(
            f"multiuser_{session.id}",
            {
                "type": "change_case",
                "case_id": case.id
            }
        )
    
    session.refresh_from_db()
    assert session.active_case == case
    assertContains(response, "Interactive DICOM Viewer")