import importlib.util
import os
from pathlib import Path
import subprocess
import unittest
from unittest.mock import patch

spec=importlib.util.spec_from_file_location('bridge',Path(__file__).with_name('bridge.py'))
bridge=importlib.util.module_from_spec(spec);spec.loader.exec_module(bridge)

class DeliveryTests(unittest.TestCase):
    def setUp(self):
        self.env=patch.dict(os.environ,POSTBOX='/bin/postbox',BESZEL_ALERT_RECIPIENT='infra-ops')
        self.env.start();self.addCleanup(self.env.stop)
    def test_posts_body_as_stdin_and_returns_receipt(self):
        with patch.object(bridge.subprocess,'run',return_value=subprocess.CompletedProcess([],0,'{"message_id": 42}','')) as run:
            self.assertEqual(bridge.deliver({'title':'Disk 85%','message':'tank is full'})['message_id'],42)
            args,kw=run.call_args
            self.assertEqual(args[0],['/bin/postbox','--json','send','--to','infra-ops','--subject','[Beszel] Disk 85%'])
            self.assertIn('tank is full',kw['input'])
    def test_delivery_failure_is_not_success(self):
        with patch.object(bridge.subprocess,'run',return_value=subprocess.CompletedProcess([],2,'','post office unavailable')):
            with self.assertRaises(RuntimeError):bridge.deliver({'message':'disk full'})
    def test_rejects_empty_message_without_sending(self):
        with patch.object(bridge.subprocess,'run') as run:
            with self.assertRaises(ValueError):bridge.deliver({'message':''})
            run.assert_not_called()

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