from django.core.checks import Error
from django.core.checks.translation import (
    check_language_settings_consistent, check_setting_language_code,
    check_setting_languages, check_setting_languages_bidi,
)
from django.test import SimpleTestCase, override_settings


class TranslationCheckTests(SimpleTestCase):

    def setUp(self):
        self.valid_tags = (
            'en',              # language
            'mas',             # language
            'sgn-ase',         # language+extlang
            'fr-CA',           # language+region
            'es-419',          # language+region
            'zh-Hans',         # language+script
            'ca-ES-valencia',  # language+region+variant
            # FIXME: The following should be invalid:
            'sr@latin',        # language+script
        )
        self.invalid_tags = (
            None,              # invalid type: None.
            123,               # invalid type: int.
            b'en',             # invalid type: bytes.
            'eü',              # non-latin characters.
            'en_US',           # locale format.
            'en--us',          # empty subtag.
            '-en',             # leading separator.
            'en-',             # trailing separator.
            'en-US.UTF-8',     # language tag w/ locale encoding.
            'en_US.UTF-8',     # locale format - language w/ region and encoding.
            'ca_ES@valencia',  # locale format - language w/ region and variant.
            # FIXME: The following should be invalid:
            # 'sr@latin',      # locale instead of language tag.
        )

    def test_valid_language_code(self):
        for tag in self.valid_tags:
            with self.subTest(tag), self.settings(LANGUAGE_CODE=tag):
                self.assertEqual(check_setting_language_code(None), [])

    def test_invalid_language_code(self):
        msg = 'You have provided an invalid value for the LANGUAGE_CODE setting: %r.'
        for tag in self.invalid_tags:
            with self.subTest(tag), self.settings(LANGUAGE_CODE=tag):
                self.assertEqual(check_setting_language_code(None), [
                    Error(msg % tag, id='translation.E001'),
                ])

    def test_valid_languages(self):
        for tag in self.valid_tags:
            with self.subTest(tag), self.settings(LANGUAGES=[(tag, tag)]):
                self.assertEqual(check_setting_languages(None), [])

    def test_invalid_languages(self):
        msg = 'You have provided an invalid language code in the LANGUAGES setting: %r.'
        for tag in self.invalid_tags:
            with self.subTest(tag), self.settings(LANGUAGES=[(tag, tag)]):
                self.assertEqual(check_setting_languages(None), [
                    Error(msg % tag, id='translation.E002'),
                ])

    def test_valid_languages_bidi(self):
        for tag in self.valid_tags:
            with self.subTest(tag), self.settings(LANGUAGES_BIDI=[tag]):
                self.assertEqual(check_setting_languages_bidi(None), [])

    def test_invalid_languages_bidi(self):
        msg = 'You have provided an invalid language code in the LANGUAGES_BIDI setting: %r.'
        for tag in self.invalid_tags:
            with self.subTest(tag), self.settings(LANGUAGES_BIDI=[tag]):
                self.assertEqual(check_setting_languages_bidi(None), [
                    Error(msg % tag, id='translation.E003'),
                ])

    @override_settings(USE_I18N=True, LANGUAGES=[('en', 'English')])
    def test_inconsistent_language_settings(self):
        msg = (
            'You have provided a value for the LANGUAGE_CODE setting that is '
            'not in the LANGUAGES setting.'
        )
        for tag in ['fr', 'fr-CA', 'fr-357']:
            with self.subTest(tag), self.settings(LANGUAGE_CODE=tag):
                self.assertEqual(check_language_settings_consistent(None), [
                    Error(msg, id='translation.E004'),
                ])

    @override_settings(
        USE_I18N=True,
        LANGUAGES=[
            ('de', 'German'),
            ('es', 'Spanish'),
            ('fr', 'French'),
            ('ca', 'Catalan'),
        ],
    )
    def test_valid_variant_consistent_language_settings(self):
        tests = [
            # language + region.
            'fr-CA',
            'es-419',
            'de-at',
            # language + region + variant.
            'ca-ES-valencia',
        ]
        for tag in tests:
            with self.subTest(tag), self.settings(LANGUAGE_CODE=tag):
                self.assertEqual(check_language_settings_consistent(None), [])