import pathlib

from django.core.checks import Warning
from django.core.checks.caches import (
    E001, check_cache_location_not_exposed, check_default_cache_is_configured,
    check_file_based_cache_is_absolute,
)
from django.test import SimpleTestCase
from django.test.utils import override_settings


class CheckCacheSettingsAppDirsTest(SimpleTestCase):
    VALID_CACHES_CONFIGURATION = {
        'default': {
            'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
        },
    }
    INVALID_CACHES_CONFIGURATION = {
        'other': {
            'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
        },
    }

    @override_settings(CACHES=VALID_CACHES_CONFIGURATION)
    def test_default_cache_included(self):
        """
        Don't error if 'default' is present in CACHES setting.
        """
        self.assertEqual(check_default_cache_is_configured(None), [])

    @override_settings(CACHES=INVALID_CACHES_CONFIGURATION)
    def test_default_cache_not_included(self):
        """
        Error if 'default' not present in CACHES setting.
        """
        self.assertEqual(check_default_cache_is_configured(None), [E001])


class CheckCacheLocationTest(SimpleTestCase):
    warning_message = (
        "Your 'default' cache configuration might expose your cache or lead "
        "to corruption of your data because its LOCATION %s %s."
    )

    @staticmethod
    def get_settings(setting, cache_path, setting_path):
        return {
            'CACHES': {
                'default': {
                    'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache',
                    'LOCATION': cache_path,
                },
            },
            setting: [setting_path] if setting == 'STATICFILES_DIRS' else setting_path,
        }

    def test_cache_path_matches_media_static_setting(self):
        root = pathlib.Path.cwd()
        for setting in ('MEDIA_ROOT', 'STATIC_ROOT', 'STATICFILES_DIRS'):
            settings = self.get_settings(setting, root, root)
            with self.subTest(setting=setting), self.settings(**settings):
                msg = self.warning_message % ('matches', setting)
                self.assertEqual(check_cache_location_not_exposed(None), [
                    Warning(msg, id='caches.W002'),
                ])

    def test_cache_path_inside_media_static_setting(self):
        root = pathlib.Path.cwd()
        for setting in ('MEDIA_ROOT', 'STATIC_ROOT', 'STATICFILES_DIRS'):
            settings = self.get_settings(setting, root / 'cache', root)
            with self.subTest(setting=setting), self.settings(**settings):
                msg = self.warning_message % ('is inside', setting)
                self.assertEqual(check_cache_location_not_exposed(None), [
                    Warning(msg, id='caches.W002'),
                ])

    def test_cache_path_contains_media_static_setting(self):
        root = pathlib.Path.cwd()
        for setting in ('MEDIA_ROOT', 'STATIC_ROOT', 'STATICFILES_DIRS'):
            settings = self.get_settings(setting, root, root / 'other')
            with self.subTest(setting=setting), self.settings(**settings):
                msg = self.warning_message % ('contains', setting)
                self.assertEqual(check_cache_location_not_exposed(None), [
                    Warning(msg, id='caches.W002'),
                ])

    def test_cache_path_not_conflict(self):
        root = pathlib.Path.cwd()
        for setting in ('MEDIA_ROOT', 'STATIC_ROOT', 'STATICFILES_DIRS'):
            settings = self.get_settings(setting, root / 'cache', root / 'other')
            with self.subTest(setting=setting), self.settings(**settings):
                self.assertEqual(check_cache_location_not_exposed(None), [])


class CheckCacheAbsolutePath(SimpleTestCase):
    def test_absolute_path(self):
        with self.settings(CACHES={
            'default': {
                'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache',
                'LOCATION': pathlib.Path.cwd() / 'cache',
            },
        }):
            self.assertEqual(check_file_based_cache_is_absolute(None), [])

    def test_relative_path(self):
        with self.settings(CACHES={
            'default': {
                'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache',
                'LOCATION': 'cache',
            },
        }):
            self.assertEqual(check_file_based_cache_is_absolute(None), [
                Warning(
                    "Your 'default' cache LOCATION path is relative. Use an "
                    "absolute path instead.",
                    id='caches.W003',
                ),
            ])