import unittest
from unittest.mock import Mock

from PyViCare.PyViCareCachedService import ViCareCachedService
from PyViCare.PyViCareService import ViCareDeviceAccessor
from PyViCare.PyViCareUtils import (PyViCareDeviceCommunicationError,
                                    PyViCareInternalServerError,
                                    PyViCareInvalidDataError,
                                    PyViCareNotSupportedFeatureError)
from tests.helper import now_is


class PyViCareCachedServiceTest(unittest.TestCase):

    CACHE_DURATION = 60

    def setUp(self):
        self.oauth_mock = Mock()
        self.oauth_mock.get.return_value = {'data': [{"feature": "someprop"}]}
        self.accessor = ViCareDeviceAccessor("[id]", "[serial]", "[device]")
        self.service = ViCareCachedService(
            self.oauth_mock, [], self.CACHE_DURATION)

    def test_fetch_all_features_is_cached(self):
        """fetch_all_features() must warm the cache, like the gateway variant.

        Callers that refresh with fetch_all_features() and then read properties
        would otherwise pay for two requests per interval.
        """
        with now_is('2000-01-01 00:00:00'):
            self.service.fetch_all_features(self.accessor)
            self.service.getProperty(self.accessor, "someprop")
        self.assertEqual(self.oauth_mock.get.call_count, 1)

    def test_getProperty_existing(self):
        self.service.getProperty(self.accessor, "someprop")
        self.oauth_mock.get.assert_called_once_with(
            '/features/installations/[id]/gateways/[serial]/devices/[device]/features/')

    def test_getProperty_nonexisting_raises_exception(self):

        def func():
            return self.service.getProperty(self.accessor, "some-non-prop")
        self.assertRaises(PyViCareNotSupportedFeatureError, func)

    def test_setProperty_works(self):
        self.service.setProperty(self.accessor, "someotherprop", "doaction", {'name': 'abc'})
        self.oauth_mock.post.assert_called_once_with(
            '/features/installations/[id]/gateways/[serial]/devices/[device]/features/someotherprop/commands/doaction', '{"name": "abc"}')

    def test_getProperty_existing_cached(self):
        # time+0 seconds
        with now_is('2000-01-01 00:00:00'):
            self.service.getProperty(self.accessor, "someprop")
            self.service.getProperty(self.accessor, "someprop")

        # time+30 seconds
        with now_is('2000-01-01 00:00:30'):
            self.service.getProperty(self.accessor, "someprop")

        self.assertEqual(self.oauth_mock.get.call_count, 1)
        self.oauth_mock.get.assert_called_once_with(
            '/features/installations/[id]/gateways/[serial]/devices/[device]/features/')

        # time+70 seconds (must be more than CACHE_DURATION)
        with now_is('2000-01-01 00:01:10'):
            self.service.getProperty(self.accessor, "someprop")

        self.assertEqual(self.oauth_mock.get.call_count, 2)

    def test_setProperty_invalidateCache(self):
        # freeze time
        with now_is('2000-01-01 00:00:00'):
            self.assertEqual(self.service.is_cache_invalid(), True)
            self.service.getProperty(self.accessor, "someprop")
            self.assertEqual(self.service.is_cache_invalid(), False)

            self.service.setProperty(self.accessor,
                "someotherprop", "doaction", {'name': 'abc'})
            self.assertEqual(self.service.is_cache_invalid(), True)

            self.service.getProperty(self.accessor, "someprop")
            self.assertEqual(self.oauth_mock.get.call_count, 2)

    def test_device_communication_error_returns_stale_cache(self):
        """When device goes offline after successful fetch, return stale cache."""
        with now_is('2000-01-01 00:00:00'):
            self.service.getProperty(self.accessor, "someprop")

        # Device goes offline after cache expires
        self.oauth_mock.get.side_effect = PyViCareDeviceCommunicationError(
            {"errorType": "DEVICE_COMMUNICATION_ERROR",
             "extendedPayload": {"reason": "GATEWAY_OFFLINE"}})

        with now_is('2000-01-01 00:01:10'):
            result = self.service.getProperty(self.accessor, "someprop")

        self.assertIsNotNone(result)

    def test_server_error_returns_stale_cache(self):
        """When server returns 500 after successful fetch, return stale cache."""
        with now_is('2000-01-01 00:00:00'):
            self.service.getProperty(self.accessor, "someprop")

        self.oauth_mock.get.side_effect = PyViCareInternalServerError(
            {"statusCode": 500, "message": "Internal server error",
             "viErrorId": "test"})

        with now_is('2000-01-01 00:01:10'):
            result = self.service.getProperty(self.accessor, "someprop")

        self.assertIsNotNone(result)

    def test_device_communication_error_raises_without_cache(self):
        """When device is offline on first fetch (no cache), must raise."""
        self.oauth_mock.get.side_effect = PyViCareDeviceCommunicationError(
            {"errorType": "DEVICE_COMMUNICATION_ERROR",
             "extendedPayload": {"reason": "DEVICE_OFFLINE"}})

        with now_is('2000-01-01 00:00:00'):
            self.assertRaises(
                PyViCareDeviceCommunicationError,
                self.service.getProperty, self.accessor, "someprop")

    def test_server_error_raises_without_cache(self):
        """When server errors on first fetch (no cache), must raise."""
        self.oauth_mock.get.side_effect = PyViCareInternalServerError(
            {"statusCode": 500, "message": "Internal server error",
             "viErrorId": "test"})

        with now_is('2000-01-01 00:00:00'):
            self.assertRaises(
                PyViCareInternalServerError,
                self.service.getProperty, self.accessor, "someprop")

    def test_invalid_data_still_raises_with_cache(self):
        """PyViCareInvalidDataError (genuine bad data) must still raise even with cache."""
        with now_is('2000-01-01 00:00:00'):
            self.service.getProperty(self.accessor, "someprop")

        self.oauth_mock.get.side_effect = None
        self.oauth_mock.get.return_value = {"unexpected": "response"}

        with now_is('2000-01-01 00:01:10'):
            self.assertRaises(
                PyViCareInvalidDataError,
                self.service.getProperty, self.accessor, "someprop")
