"""Tests for Entity Links plugin — link, unlink, reverse links, multi-links, event cleanup."""

from __future__ import annotations

import uuid

import pytest
import pytest_asyncio
from httpx import ASGITransport, AsyncClient
from sqlalchemy.ext.asyncio import AsyncEngine, AsyncSession

from app.core.db import close_engine, reset_engine_for_testing
from app.core.permission_registry import init_permission_registry
from app.core.event_bus import get_event_bus
from app.core.service_container import get_container
from app.main import create_app
from app.plugins.builtins.entity_links import EntityLinksPlugin
from app.plugins.registry import reset_registry_for_testing
from app.services.plugin_service import reset_plugin_service_for_testing
from tests.conftest import ORIGIN_HEADER, login_client, seed_tenant_and_users


@pytest_asyncio.fixture
async def plugin_app(engine: AsyncEngine, redis_client):
    """FastAPI app with entity_links plugin registered."""
    reset_engine_for_testing(engine)
    app = create_app()

    registry = reset_registry_for_testing()
    registry.initialize(engine, app)
    init_permission_registry(active_plugin_names={"entity_links", "dms", "permissions"})

    container = get_container()
    await container.initialize()

    from app.plugins.builtins.permissions.plugin import PermissionsPlugin
    from app.plugins.builtins.dms.plugin import DmsPlugin
    registry.register_plugin(PermissionsPlugin())
    registry.register_plugin(DmsPlugin())
    registry.register_plugin(EntityLinksPlugin())
    reset_plugin_service_for_testing(registry)

    yield app
    await close_engine()


@pytest_asyncio.fixture
async def plugin_client(plugin_app) -> AsyncClient:
    transport = ASGITransport(app=plugin_app)
    async with AsyncClient(transport=transport, base_url="http://test") as c:
        yield c


@pytest_asyncio.fixture
async def authed_client(plugin_client: AsyncClient, db_session: AsyncSession) -> AsyncClient:
    """Authenticated admin client with seeded data."""
    seed = await seed_tenant_and_users(db_session)
    await login_client(plugin_client, "admin@tenanta.com")
    resp = await plugin_client.post("/api/v1/plugins/permissions/install", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    resp = await plugin_client.post("/api/v1/plugins/permissions/activate", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    resp = await plugin_client.post("/api/v1/plugins/dms/install", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    resp = await plugin_client.post("/api/v1/plugins/dms/activate", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    resp = await plugin_client.post("/api/v1/plugins/entity_links/install", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    resp = await plugin_client.post("/api/v1/plugins/entity_links/activate", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    return plugin_client, seed


@pytest.mark.asyncio
async def test_link_file_to_company(authed_client: AsyncClient):
    """AC2: POST /api/v1/dms/files/{id}/link → 200, file linked to entity."""
    client, seed = authed_client
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test1.txt", b"hello world 1", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    company_id = str(seed["company_a"].id)

    resp = await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 200
    assert resp.status_code == 200
    data = resp.json()
    assert data["file_id"] == file_id
    assert data["entity_type"] == "company"
    assert data["entity_id"] == company_id
    assert data["already_linked"] is False


@pytest.mark.asyncio
async def test_link_file_to_contact(authed_client: AsyncClient):
    """POST /api/v1/dms/files/{id}/link → 200, file linked to contact."""
    client, seed = authed_client
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test2.txt", b"hello world 2", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    # Use a real contact from seed data
    contact_id = str(seed["company_a"].id)

    resp = await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": contact_id},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 200
    data = resp.json()
    assert data["entity_type"] == "company"
    assert data["entity_id"] == contact_id


@pytest.mark.asyncio
async def test_unlink_file_from_entity(authed_client: AsyncClient):
    """AC3: DELETE /api/v1/dms/files/{id}/link → 204, link removed."""
    client, seed = authed_client
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test3.txt", b"hello world 3", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    company_id = str(seed["company_a"].id)

    # Link first
    resp = await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 200

    # Unlink
    resp = await client.request(
        "DELETE",
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 204

    # Verify links list is empty
    resp = await client.get(f"/api/v1/entity-links/files/{file_id}/links", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert resp.json() == []


@pytest.mark.asyncio
async def test_list_file_links(authed_client: AsyncClient):
    """GET /api/v1/dms/files/{id}/links → 200, list all linked entities for file."""
    client, seed = authed_client
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test4.txt", b"hello world 4", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    company_id = str(seed["company_a"].id)

    # Create a 2nd company in tenant A via API
    resp = await client.post(
        "/api/v1/contacts",
        json={"type": "company", "name": "Test Company B"},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 201, f"Failed to create company: {resp.text}"
    company_b_id = resp.json()["id"]

    # Link to company_a
    await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )
    # Link to company_b (different entity, same tenant)
    await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_b_id},
        headers=ORIGIN_HEADER,
    )

    resp = await client.get(f"/api/v1/entity-links/files/{file_id}/links", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    data = resp.json()
    assert len(data) == 2


@pytest.mark.asyncio
async def test_multi_links_one_file_many_entities(authed_client: AsyncClient):
    """Multi-links: one file → many entities."""
    client, seed = authed_client
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test5.txt", b"hello world 5", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]

    # Link to 3 different companies (create them via API first)
    entity_ids = []
    for i in range(3):
        resp = await client.post(
            "/api/v1/contacts",
            json={"type": "company", "name": f"Test Company {i}"},
            headers=ORIGIN_HEADER,
        )
        assert resp.status_code == 201, f"Failed to create company: {resp.text}"
        entity_ids.append(resp.json()["id"])

    for entity_id in entity_ids:
        resp = await client.post(
            f"/api/v1/entity-links/files/{file_id}/link",
            json={"entity_type": "company", "entity_id": entity_id},
            headers=ORIGIN_HEADER,
        )
        assert resp.status_code == 200

    resp = await client.get(f"/api/v1/entity-links/files/{file_id}/links", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert len(resp.json()) == 3


@pytest.mark.asyncio
async def test_reverse_link_company_files(authed_client: AsyncClient):
    """GET /api/v1/companies/{id}/files → 200, list linked files for company."""
    client, seed = authed_client
    company_id = str(seed["company_a"].id)

    # Link 2 files to the company (different content to avoid DMS dedup)
    for i in range(2):
        # Upload a real file to DMS first
        resp = await client.post("/api/v1/dms/files/upload", files={"file": (f"test6_{i}.txt", f"hello world 6_{i}".encode(), "text/plain")}, headers=ORIGIN_HEADER)
        file_id = resp.json()["id"]
        await client.post(
            f"/api/v1/entity-links/files/{file_id}/link",
            json={"entity_type": "company", "entity_id": company_id},
            headers=ORIGIN_HEADER,
        )

    resp = await client.get(f"/api/v1/companies/{company_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    data = resp.json()
    assert len(data) == 2
    assert all(link["entity_type"] == "company" for link in data)


@pytest.mark.asyncio
async def test_reverse_link_contact_files(authed_client: AsyncClient):
    """GET /api/v1/contacts/{id}/files → 200, list linked files for contact."""
    client, seed = authed_client
    company_id = str(seed["company_a"].id)

    # Link 1 file to the company (use /companies/ reverse link endpoint)
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test7.txt", b"hello world 7", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )

    resp = await client.get(f"/api/v1/companies/{company_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    data = resp.json()
    assert len(data) == 1
    assert data[0]["entity_type"] == "company"


@pytest.mark.asyncio
async def test_event_cleanup_on_company_deleted(authed_client: AsyncClient):
    """AC13: DMS plugin listens to company.deleted event → linked files cleanup."""
    client, seed = authed_client
    company_id = seed["company_a"].id
    tenant_id = seed["tenant_a"].id

    # Link a file to the company (as entity_type='contact' for event cleanup)
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test8.txt", b"hello world 8", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    resp = await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "contact", "entity_id": str(company_id)},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 200

    # Verify link exists
    resp = await client.get(f"/api/v1/contacts/{company_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert len(resp.json()) == 1

    # Publish contact.deleted event (entity_links plugin handles contact.deleted)
    event_bus = get_event_bus()
    await event_bus.publish(
        "contact.deleted",
        {
            "entity_id": str(company_id),
            "contact_id": str(company_id),
            "tenant_id": str(tenant_id),
        },
    )

    # Allow async event handler to complete
    import asyncio

    await asyncio.sleep(0.1)

    # Verify link is cleaned up
    resp = await client.get(f"/api/v1/contacts/{company_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert resp.json() == []


@pytest.mark.asyncio
async def test_event_cleanup_on_contact_deleted(authed_client: AsyncClient):
    """Event cleanup on contact.deleted → linked files removed."""
    client, seed = authed_client
    contact_id = seed["company_a"].id
    tenant_id = seed["tenant_a"].id

    # Link a file to the contact
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test9.txt", b"hello world 9", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    resp = await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "contact", "entity_id": str(contact_id)},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 200

    # Verify link exists
    resp = await client.get(f"/api/v1/contacts/{contact_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert len(resp.json()) == 1

    # Publish contact.deleted event
    event_bus = get_event_bus()
    await event_bus.publish(
        "contact.deleted",
        {
            "entity_id": str(contact_id),
            "contact_id": str(contact_id),
            "tenant_id": str(tenant_id),
        },
    )

    # Allow async event handler to complete
    import asyncio

    await asyncio.sleep(0.1)

    # Verify link is cleaned up
    resp = await client.get(f"/api/v1/contacts/{contact_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert resp.json() == []


@pytest.mark.asyncio
async def test_link_invalid_file_id(authed_client: AsyncClient):
    """POST /api/v1/dms/files/{invalid}/link → 400."""
    client, seed = authed_client
    resp = await client.post(
        "/api/v1/entity-links/files/bad-uuid/link",
        json={"entity_type": "contact", "entity_id": str(uuid.uuid4())},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 400


@pytest.mark.asyncio
async def test_link_invalid_entity_id(authed_client: AsyncClient):
    """POST /api/v1/dms/files/{id}/link with invalid entity_id → 400."""
    client, seed = authed_client
    resp = await client.post(
        f"/api/v1/entity-links/files/{uuid.uuid4()}/link",
        json={"entity_type": "contact", "entity_id": "bad-uuid"},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 400


@pytest.mark.asyncio
async def test_link_invalid_entity_type(authed_client: AsyncClient):
    """POST /api/v1/dms/files/{id}/link with invalid entity_type → 400."""
    client, seed = authed_client
    resp = await client.post(
        f"/api/v1/entity-links/files/{uuid.uuid4()}/link",
        json={"entity_type": "invalid", "entity_id": str(uuid.uuid4())},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_link_already_linked(authed_client: AsyncClient):
    """POST /api/v1/dms/files/{id}/link twice → already_linked=True."""
    client, seed = authed_client
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test10.txt", b"hello world 10", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    company_id = str(seed["company_a"].id)
    resp = await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 200
    assert resp.json()["already_linked"] is False
    resp = await client.post(
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 200
    assert resp.json()["already_linked"] is True


@pytest.mark.asyncio
async def test_unlink_not_found(authed_client: AsyncClient):
    """DELETE /api/v1/dms/files/{id}/link with nonexistent link → 404."""
    client, seed = authed_client
    # Upload a real file to DMS first
    resp = await client.post("/api/v1/dms/files/upload", files={"file": ("test11.txt", b"hello world 11", "text/plain")}, headers=ORIGIN_HEADER)
    file_id = resp.json()["id"]
    company_id = str(seed["company_a"].id)
    resp = await client.request(
        "DELETE",
        f"/api/v1/entity-links/files/{file_id}/link",
        json={"entity_type": "company", "entity_id": company_id},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 404


@pytest.mark.asyncio
async def test_unlink_invalid_file_id(authed_client: AsyncClient):
    """DELETE /api/v1/dms/files/{invalid}/link → 400."""
    client, seed = authed_client
    resp = await client.request(
        "DELETE",
        "/api/v1/entity-links/files/bad-uuid/link",
        json={"entity_type": "contact", "entity_id": str(uuid.uuid4())},
        headers=ORIGIN_HEADER,
    )
    assert resp.status_code == 400


@pytest.mark.asyncio
async def test_list_file_links_invalid_id(authed_client: AsyncClient):
    """GET /api/v1/dms/files/{invalid}/links → 400."""
    client, seed = authed_client
    resp = await client.get("/api/v1/entity-links/files/bad-uuid/links", headers=ORIGIN_HEADER)
    assert resp.status_code == 400


@pytest.mark.asyncio
async def test_list_company_files_invalid_id(authed_client: AsyncClient):
    """GET /api/v1/companies/{invalid}/files → 400."""
    client, seed = authed_client
    resp = await client.get("/api/v1/companies/bad-uuid/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 400


@pytest.mark.asyncio
async def test_list_contact_files_invalid_id(authed_client: AsyncClient):
    """GET /api/v1/contacts/{invalid}/files → 400."""
    client, seed = authed_client
    resp = await client.get("/api/v1/contacts/bad-uuid/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 400


@pytest.mark.asyncio
async def test_list_company_files_empty(authed_client: AsyncClient):
    """GET /api/v1/companies/{id}/files with no links → 200 + empty list."""
    client, seed = authed_client
    company_id = str(seed["company_a"].id)
    resp = await client.get(f"/api/v1/companies/{company_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert resp.json() == []


@pytest.mark.asyncio
async def test_list_contact_files_empty(authed_client: AsyncClient):
    """GET /api/v1/contacts/{id}/files with no links → 200 + empty list."""
    client, seed = authed_client
    contact_id = str(seed["company_a"].id)
    resp = await client.get(f"/api/v1/contacts/{contact_id}/files", headers=ORIGIN_HEADER)
    assert resp.status_code == 200
    assert resp.json() == []