import pytest
import pytest_asyncio
import tempfile
import shutil
import sys
import os
import uuid
import configparser
import base64
import stat
import resource
import platform

from fastapi import FastAPI
from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
from httpx import AsyncClient
from httpx_ws.transport import ASGIWebSocketTransport
from unittest.mock import MagicMock, patch
from pathlib import Path
from typing import AsyncGenerator, Any

from gns3server.controller import Controller
from gns3server.config import Config
from gns3server.compute import MODULES
from gns3server.compute.port_manager import PortManager
from gns3server.compute.project_manager import ProjectManager
from gns3server.db.models import Base, User, Compute
from gns3server.db.repositories.users import UsersRepository
from gns3server.db.repositories.computes import ComputesRepository
from gns3server.api.routes.controller.dependencies.database import get_db_session
from gns3server import schemas
from gns3server.schemas.controller.computes import Protocol
from gns3server.services import auth_service
from gns3server.services.authentication import DEFAULT_JWT_SECRET_KEY

sys._called_from_test = True
sys.original_platform = sys.platform


def pytest_configure(config):
    """
    Increases the maximum number of open file descriptors before running tests (Unix only).
    """

    if platform.system() != "Windows":
        soft, hard = resource.getrlimit(resource.RLIMIT_NOFILE)
        # Set soft limit to hard limit, or a safe high number like 4096
        new_soft = min(4096, hard)
        if soft < new_soft:
            resource.setrlimit(resource.RLIMIT_NOFILE, (new_soft, hard))


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def app() -> AsyncGenerator[Any, Any]:

    from gns3server.api.server import app as gns3app
    yield gns3app


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def db_engine():

    db_url = os.getenv("GNS3_TEST_DATABASE_URI", "sqlite+aiosqlite:///:memory:")  # "sqlite:///./sql_test_app.db"
    engine = create_async_engine(db_url, connect_args={"check_same_thread": False}, future=True)
    try:
        yield engine
    finally:
        await engine.dispose()


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def db_session(db_engine):

    # recreate database tables for each class
    # preferred and faster way would be to rollback the session/transaction
    # but it doesn't work for some reason
    async with db_engine.connect() as conn:
        # Speed up tests by avoiding to hash the 'admin' password everytime the default super admin is added
        # to the database using the "after_create" sqlalchemy event
        hashed_password = "$2b$12$jPsNU9IS7.EWEqXahtDfo.26w6VLOLCuFEHKNvDpOjxs5e0WpqJfa"
        with patch("gns3server.services.authentication.AuthService.hash_password", return_value=hashed_password):
            await conn.run_sync(Base.metadata.drop_all)
            await conn.run_sync(Base.metadata.create_all)

    session = AsyncSession(db_engine, expire_on_commit=False)
    try:
        yield session
    finally:
        await session.close()


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def base_client(app: FastAPI, db_session: AsyncSession) -> AsyncGenerator[AsyncClient, Any]:

    async def _get_test_db():
        try:
            yield db_session
        finally:
            pass

    app.dependency_overrides[get_db_session] = _get_test_db

    async with AsyncClient(
            base_url="http://test-api",
            headers={"Content-Type": "application/json"},
            transport=ASGIWebSocketTransport(app=app)
    ) as async_client:
        yield async_client


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def test_user(db_session: AsyncSession) -> User:

    new_user = schemas.UserCreate(
        username="user1",
        email="user1@email.com",
        password="user1_password",
    )
    user_repo = UsersRepository(db_session)
    existing_user = await user_repo.get_user_by_username(new_user.username)
    if existing_user:
        return existing_user
    user = await user_repo.create_user(new_user)

    # add new user to the "Users" group
    group = await user_repo.get_user_group_by_name("Users")
    await user_repo.add_member_to_user_group(group.user_group_id, user)
    return user


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def test_compute(db_session: AsyncSession) -> Compute:

    new_compute = schemas.ComputeCreate(
        compute_id=uuid.uuid4(),
        protocol=Protocol.http,
        host="localhost",
        port=4242,
        user="julien",
        password="secure"
    )

    compute_repo = ComputesRepository(db_session)
    existing_compute = await compute_repo.get_compute(new_compute.compute_id)
    if existing_compute:
        return existing_compute
    return await compute_repo.create_compute(new_compute)


@pytest_asyncio.fixture(loop_scope="class", scope="class")
def unauthorized_client(base_client: AsyncClient, test_user: User) -> AsyncClient:
    return base_client


@pytest_asyncio.fixture(loop_scope="class", scope="class")
def authorized_client(base_client: AsyncClient, test_user: User) -> AsyncClient:

    # Sign with the default secret key: the class-scoped token must stay valid
    # across every test, but "run_around_tests" resets the config and forces
    # jwt_secret_key back to the default for each test function.
    access_token = auth_service.create_access_token(test_user.username, secret_key=DEFAULT_JWT_SECRET_KEY)
    base_client.headers = {
        **base_client.headers,
        "Authorization": f"Bearer {access_token}",
    }
    return base_client


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def client(base_client: AsyncClient) -> AsyncClient:

    # The super admin is automatically created when the users table is created
    # this account that can access all endpoints without restrictions.
    # Sign with the default secret key so the token matches the one enforced
    # by "run_around_tests" when the config is reset for each test function.
    access_token = auth_service.create_access_token("admin", secret_key=DEFAULT_JWT_SECRET_KEY)
    base_client.headers = {
        **base_client.headers,
        "Authorization": f"Bearer {access_token}",
    }
    return base_client


@pytest_asyncio.fixture(loop_scope="class", scope="class")
async def compute_client(base_client: AsyncClient) -> AsyncClient:

    # default compute username is 'gns3'
    base64_credentials = base64.b64encode(b"gns3:").decode("ascii")
    base_client.headers = {
        **base_client.headers,
        "Authorization": f"Basic {base64_credentials}",
    }
    return base_client


@pytest.fixture
def controller_config_path(tmpdir):

    return str(tmpdir / "config" / "gns3_controller.conf")


@pytest.fixture
def controller(tmpdir, controller_config_path):

    Controller._instance = None
    controller = Controller.instance()
    os.makedirs(os.path.dirname(controller_config_path), exist_ok=True)
    Path(controller_config_path).touch()
    controller._config_file = controller_config_path
    controller._config_loaded = True
    return controller


@pytest.fixture
def compute(controller):

    compute = MagicMock()
    compute.id = "example.com"
    controller._computes = {"example.com": compute}
    return compute


@pytest_asyncio.fixture
async def project(tmpdir, controller):

    return await controller.add_project(name="Test")


@pytest.fixture
def compute_project(tmpdir):

    return ProjectManager.instance().create_project(project_id="a1e920ca-338a-4e9f-b363-aa607b09dd80")


@pytest.fixture
def config(tmpdir):

    path = str(tmpdir / "server.conf")
    config = configparser.ConfigParser()
    with open(path, "w+") as f:
        config.write(f)
    Config.reset()
    config = Config.instance(files=[path])
    config.clear()
    return config


@pytest.fixture
def images_dir(config):
    """
    Get the location of images
    """

    path = config.settings.Server.images_path
    os.makedirs(path, exist_ok=True)
    os.makedirs(os.path.join(path, "QEMU"), exist_ok=True)
    os.makedirs(os.path.join(path, "IOU"), exist_ok=True)
    return path


@pytest.fixture
def symbols_dir(config):
    """
    Get the location of symbols
    """

    path = config.settings.Server.symbols_path
    os.makedirs(path, exist_ok=True)
    return path


@pytest.fixture
def projects_dir(config):
    """
    Get the location of images
    """

    path = config.settings.Server.projects_path
    os.makedirs(path, exist_ok=True)
    return path


@pytest.fixture(scope="function")
def port_manager():
    """An instance of port manager"""

    PortManager._instance = None
    p = PortManager.instance()
    p.console_host = "127.0.0.1"
    return p


@pytest.fixture(scope="function")
def free_console_port(port_manager, compute_project):
    """Get a free TCP port"""

    # In case of already use ports we will raise an exception
    port = port_manager.get_free_tcp_port(compute_project)
    # We release the port immediately in order to allow
    # the test do whatever the test want
    port_manager.release_tcp_port(port, compute_project)
    return port


@pytest.fixture
def darwin_platform():
    """
    Change sys.plaform to Darwin
    """

    old_platform = sys.platform
    sys.platform = "darwin10.10"
    yield
    sys.plaform = old_platform


@pytest.fixture
def windows_platform():
    """
    Change sys.platform to Windows
    """

    old_platform = sys.platform
    sys.platform = "win10"
    yield
    sys.plaform = old_platform


@pytest.fixture
def linux_platform():
    """
    Change sys.platform to Linux
    """

    old_platform = sys.platform
    sys.platform = "linuxdebian"
    yield
    sys.plaform = old_platform


@pytest.fixture
def on_gns3vm(linux_platform):
    """
    Mock the hostname to  emulate the GNS3 VM
    """

    with patch("gns3server.utils.interfaces.interfaces", return_value=[
            {"name": "eth0", "special": False, "type": "ethernet", "ip_addresses": [], "status": "up", "speed": 1000, "mtu": 1500, "flags": ["up", "broadcast", "running", "multicast"]},
            {"name": "eth1", "special": False, "type": "ethernet", "ip_addresses": [], "status": "down", "speed": 0, "mtu": 1500, "flags": ["broadcast"]},
            {"name": "virbr0", "special": True, "type": "ethernet", "ip_addresses": [], "status": "up", "speed": 10000, "mtu": 1500, "flags": ["up", "broadcast", "running", "multicast"]}]):
        with patch("socket.gethostname", return_value="gns3vm"):
            yield


@pytest.fixture
def ethernet_device():

    import psutil
    return sorted(psutil.net_if_addrs().keys())[0]


@pytest.fixture
def ubridge_path(config):
    """
    Get the location of a fake ubridge
    """

    path = config.settings.Server.ubridge_path
    os.makedirs(os.path.dirname(path), exist_ok=True)
    open(path, 'w+').close()
    return path


@pytest.fixture(autouse=True)
def run_around_tests(monkeypatch, config, port_manager):
    """
    This setup a temporary project file environment around tests
    """

    tmppath = tempfile.mkdtemp()

    for module in MODULES:
        module._instance = None

    config.settings.Controller.jwt_secret_key = DEFAULT_JWT_SECRET_KEY

    secrets_dir = os.path.join(tmppath, 'secrets')
    os.makedirs(secrets_dir)
    config.settings.Server.secrets_dir = secrets_dir

    projects_dir = os.path.join(tmppath, 'projects')
    os.makedirs(projects_dir)
    config.settings.Server.projects_path = projects_dir

    symbols_dir = os.path.join(tmppath, 'symbols')
    os.makedirs(symbols_dir)
    config.settings.Server.symbols_path = symbols_dir

    images_dir = os.path.join(tmppath, 'images')
    os.makedirs(images_dir)
    config.settings.Server.images_path = images_dir

    appliances_dir = os.path.join(tmppath, 'appliances')
    os.makedirs(appliances_dir)
    config.settings.Server.appliances_path = appliances_dir

    config.settings.Server.ubridge_path = os.path.join(tmppath, 'bin', 'ubridge')

    # Prevent executions of the VM if we forgot to mock something
    config.settings.VirtualBox.vboxmanage_path = tmppath
    config.settings.VPCS.vpcs_path = tmppath
    config.settings.VMware.vmrun_path = tmppath
    config.settings.Dynamips.dynamips_path = tmppath

    # Force turn off KVM because it's not available on CI
    config.settings.Qemu.enable_hardware_acceleration = False

    # avoid monitoring for new images while testing
    config.settings.Server.auto_discover_images = False

    monkeypatch.setattr("gns3server.utils.path.get_default_project_directory", lambda *args: os.path.join(tmppath, 'projects'))

    # Force sys.platform to the original value. Because it seems not be restored correctly after each test
    sys.platform = sys.original_platform

    yield

    # A helper should not raise Exception
    try:
        shutil.rmtree(tmppath)
    except BaseException:
        pass


@pytest.fixture
def fake_executable(monkeypatch, tmpdir) -> str:

    monkeypatch.setenv("PATH", str(tmpdir))
    executable_path = os.path.join(os.environ["PATH"], "fake_executable")
    with open(executable_path, "w+") as f:
        f.write("1")
    os.chmod(executable_path, stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR)
    return executable_path