"""Ensure port coordination never treats another service's port as ours."""
import json
import unittest
from unittest.mock import MagicMock, patch
import deploy


class PortGuardTests(unittest.TestCase):
    def test_foreign_listener_blocks_deployment(self):
        probe = MagicMock()
        probe.__enter__.return_value.bind.side_effect = OSError("Address already in use")
        with patch.object(deploy, "run", return_value=""), patch.object(deploy.socket, "socket", return_value=probe):
            with self.assertRaisesRegex(RuntimeError, "already occupied"):
                deploy.check_port(18135)

    def test_current_service_can_keep_its_port(self):
        details = [{"NetworkSettings": {"Ports": {"3000/tcp": [{"HostPort": "18135"}]}}}]
        with patch.object(deploy, "run", side_effect=["our-container", json.dumps(details)]), patch.object(deploy.socket, "socket") as probe:
            deploy.check_port(18135)
            probe.assert_not_called()

    def test_current_service_on_another_port_does_not_bypass_conflict(self):
        details = [{"NetworkSettings": {"Ports": {"3000/tcp": [{"HostPort": "18134"}]}}}]
        probe = MagicMock()
        probe.__enter__.return_value.bind.side_effect = OSError("Address already in use")
        with patch.object(deploy, "run", side_effect=["our-container", json.dumps(details)]), patch.object(deploy.socket, "socket", return_value=probe):
            with self.assertRaisesRegex(RuntimeError, "already occupied"):
                deploy.check_port(18135)


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