import copy
import importlib.util
from pathlib import Path
import unittest

path = Path(__file__).with_name('activate_forge_template.py')
spec = importlib.util.spec_from_file_location('template', path)
t = importlib.util.module_from_spec(spec)
spec.loader.exec_module(t)


def fixture():
    def container(name):
        return {'name': name, 'image': 'unchanged:fixture', 'resources': {'requests': {'cpu': '100m'}},
                'volumeMounts': [{'name': 'data', 'mountPath': '/data'}],
                'env': [{'name': 'EXISTING_REFERENCE', 'valueFrom': {'secretKeyRef': {'name': 'existing', 'key': 'reference-only'}}}]}
    return {'metadata': {'uid': 'fixed', 'resourceVersion': '17'}, 'spec': {'template': {'metadata': {'labels': {'preserved': 'yes'}},
        'spec': {'volumes': [{'name': 'data', 'persistentVolumeClaim': {'claimName': 'existing'}}],
                 'initContainers': [container('init-directories'), container('init-app-ini'), container('configure-gitea')],
                 'containers': [container('gitea')]}}}}


class Tests(unittest.TestCase):
    def test_rollback_preserves_existing_configuration_and_explicitly_restores_default(self):
        before = fixture()
        active = t.apply_locally(before, t.patch_for(before))
        rolled = t.apply_locally(active, t.patch_for(active, rollback=True))
        expected = copy.deepcopy(before)
        expected['spec']['template']['spec']['initContainers'][1]['env'].append({'name': t.SETTING, 'value': t.DEFAULT})
        self.assertEqual(rolled, expected)
        self.assertEqual(before, fixture())

    def test_stale_resource_version_cannot_apply(self):
        before = fixture()
        patch = t.patch_for(before)
        before['metadata']['resourceVersion'] = '18'
        with self.assertRaisesRegex(ValueError, 'precondition'):
            t.apply_locally(before, patch)

    def test_existing_setting_not_overwritten(self):
        d = fixture()
        d['spec']['template']['spec']['initContainers'][1]['env'].append({'name': t.SETTING, 'value': '/unknown'})
        with self.assertRaisesRegex(ValueError, 'setting-preexists'):
            t.patch_for(d)

    def test_conflicting_mount_not_overwritten(self):
        d = fixture()
        d['spec']['template']['spec']['containers'][0]['volumeMounts'].append({'name': 'other', 'mountPath': t.MOUNT['mountPath']})
        with self.assertRaisesRegex(ValueError, 'mount-preexists'):
            t.patch_for(d)

    def test_rollback_preserves_concurrently_modified_mount(self):
        d = fixture()
        d = t.apply_locally(d, t.patch_for(d))
        d['spec']['template']['spec']['containers'][0]['volumeMounts'][-1]['subPath'] = 'unknown'
        original = copy.deepcopy(d)
        with self.assertRaisesRegex(ValueError, 'rollback-mount-changed'):
            t.patch_for(d, rollback=True)
        self.assertEqual(d, original)

    def test_missing_configuration_container_refused(self):
        d = fixture()
        d['spec']['template']['spec']['initContainers'].pop(1)
        with self.assertRaisesRegex(ValueError, 'configuration-container'):
            t.patch_for(d)


if __name__ == '__main__':
    unittest.main(verbosity=2)