#!/usr/bin/env python3
"""Tests for ip_utils — IP derivation from subnet."""

import sys
import os
import tempfile
import unittest
from pathlib import Path

api_dir = Path(__file__).parent.parent / 'api'
sys.path.insert(0, str(api_dir))

import ip_utils


class TestGetServiceIps(unittest.TestCase):
    def setUp(self):
        self.ips = ip_utils.get_service_ips('172.20.0.0/16')

    def test_returns_all_keys(self):
        for name in ip_utils.CONTAINER_OFFSETS:
            self.assertIn(name, self.ips)

    def test_default_subnet_caddy(self):
        self.assertEqual(self.ips['caddy'], '172.20.0.2')

    def test_default_subnet_dns(self):
        self.assertEqual(self.ips['dns'], '172.20.0.3')

    def test_default_subnet_api(self):
        self.assertEqual(self.ips['api'], '172.20.0.10')

    def test_default_subnet_virtual_ips(self):
        self.assertEqual(self.ips['vip_calendar'], '172.20.0.21')
        self.assertEqual(self.ips['vip_files'],    '172.20.0.22')
        self.assertEqual(self.ips['vip_mail'],     '172.20.0.23')
        self.assertEqual(self.ips['vip_webdav'],   '172.20.0.24')

    def test_different_subnet_shifts_all_ips(self):
        ips = ip_utils.get_service_ips('10.0.0.0/24')
        self.assertEqual(ips['caddy'],        '10.0.0.2')
        self.assertEqual(ips['dns'],          '10.0.0.3')
        self.assertEqual(ips['api'],          '10.0.0.10')
        self.assertEqual(ips['vip_calendar'], '10.0.0.21')

    def test_non_zero_third_octet_subnet(self):
        ips = ip_utils.get_service_ips('192.168.5.0/24')
        self.assertEqual(ips['caddy'], '192.168.5.2')
        self.assertEqual(ips['vip_webdav'], '192.168.5.24')

    def test_strict_false_accepts_host_bit_set(self):
        # e.g. user types "172.20.0.1/16" — should work same as "172.20.0.0/16"
        ips = ip_utils.get_service_ips('172.20.0.1/16')
        self.assertEqual(ips['caddy'], '172.20.0.2')

    def test_all_ips_are_strings(self):
        for name, ip in self.ips.items():
            self.assertIsInstance(ip, str, f'{name} is not a string')

    def test_all_ips_unique(self):
        self.assertEqual(len(set(self.ips.values())), len(self.ips))


class TestGetVirtualIps(unittest.TestCase):
    def test_returns_four_services(self):
        vips = ip_utils.get_virtual_ips('172.20.0.0/16')
        self.assertEqual(set(vips.keys()), {'calendar', 'files', 'mail', 'webdav'})

    def test_values_match_get_service_ips(self):
        full = ip_utils.get_service_ips('172.20.0.0/16')
        vips = ip_utils.get_virtual_ips('172.20.0.0/16')
        self.assertEqual(vips['calendar'], full['vip_calendar'])
        self.assertEqual(vips['files'],    full['vip_files'])
        self.assertEqual(vips['mail'],     full['vip_mail'])
        self.assertEqual(vips['webdav'],   full['vip_webdav'])

    def test_different_subnet(self):
        vips = ip_utils.get_virtual_ips('10.10.0.0/16')
        self.assertEqual(vips['calendar'], '10.10.0.21')
        self.assertEqual(vips['webdav'],   '10.10.0.24')


class TestUpdateDockerComposeIps(unittest.TestCase):
    COMPOSE_TEMPLATE = """\
version: '3.3'
services:
  caddy:
    networks:
      cell-network:
        ipv4_address: 172.20.0.2
  dns:
    networks:
      cell-network:
        ipv4_address: 172.20.0.3
  api:
    networks:
      cell-network:
        ipv4_address: 172.20.0.10
networks:
  cell-network:
    ipam:
      config:
        - subnet: 172.20.0.0/16
"""

    def setUp(self):
        self.tmp = tempfile.NamedTemporaryFile(mode='w', suffix='.yml', delete=False)
        self.tmp.write(self.COMPOSE_TEMPLATE)
        self.tmp.close()

    def tearDown(self):
        os.unlink(self.tmp.name)

    def test_returns_false_for_missing_file(self):
        self.assertFalse(
            ip_utils.update_docker_compose_ips('172.20.0.0/16', '10.0.0.0/24', '/nonexistent/path.yml')
        )

    def test_subnet_updated(self):
        ip_utils.update_docker_compose_ips('172.20.0.0/16', '10.0.0.0/24', self.tmp.name)
        with open(self.tmp.name) as f:
            content = f.read()
        self.assertIn('10.0.0.0/24', content)
        self.assertNotIn('172.20.0.0/16', content)

    def test_caddy_ip_updated(self):
        ip_utils.update_docker_compose_ips('172.20.0.0/16', '10.0.0.0/24', self.tmp.name)
        with open(self.tmp.name) as f:
            content = f.read()
        self.assertIn('10.0.0.2', content)
        self.assertNotIn('172.20.0.2', content)

    def test_api_ip_updated(self):
        ip_utils.update_docker_compose_ips('172.20.0.0/16', '10.0.0.0/24', self.tmp.name)
        with open(self.tmp.name) as f:
            content = f.read()
        self.assertIn('10.0.0.10', content)
        self.assertNotIn('172.20.0.10', content)

    def test_returns_true_on_success(self):
        result = ip_utils.update_docker_compose_ips('172.20.0.0/16', '10.0.0.0/24', self.tmp.name)
        self.assertTrue(result)

    def test_noop_when_ranges_same(self):
        ip_utils.update_docker_compose_ips('172.20.0.0/16', '172.20.0.0/16', self.tmp.name)
        with open(self.tmp.name) as f:
            content = f.read()
        self.assertEqual(content, self.COMPOSE_TEMPLATE)


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