#!/usr/bin/env python3
"""
Edge-case tests for peer management endpoints in api/app.py.

Key scenarios:
- POST /api/peers with subnet exhaustion (_next_peer_ip raises ValueError) → 409
- POST /api/peers/<name>/clear-reinstall: success (200)
- POST /api/peers/<name>/clear-reinstall: unknown peer raises → 500
- POST /api/ip-update: missing 'peer' field → 400
- POST /api/ip-update: missing 'ip' field → 400
- POST /api/ip-update: unknown peer → 404
- POST /api/ip-update: success → 200
"""

import sys
import json
import unittest
from pathlib import Path
from unittest.mock import patch, MagicMock

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

from app import app


class TestAddPeerSubnetExhaustion(unittest.TestCase):
    """POST /api/peers with no free IPs left must return 409, not 500."""

    def setUp(self):
        app.config['TESTING'] = True
        self.client = app.test_client()

    @patch('app._next_peer_ip')
    @patch('app.auth_manager')
    def test_add_peer_returns_409_when_subnet_exhausted(self, mock_auth, mock_next_ip):
        mock_auth.create_user.return_value = True
        mock_next_ip.side_effect = ValueError('No free IPs left in 10.0.0.0/24')

        r = self.client.post(
            '/api/peers',
            data=json.dumps({
                'name': 'newpeer',
                'public_key': 'PUBKEY==',
                'password': 'verysecret123',
            }),
            content_type='application/json',
        )
        self.assertEqual(r.status_code, 409)
        data = json.loads(r.data)
        self.assertIn('error', data)

    @patch('app._next_peer_ip')
    @patch('app.auth_manager')
    def test_add_peer_409_error_message_mentions_ip(self, mock_auth, mock_next_ip):
        mock_auth.create_user.return_value = True
        mock_next_ip.side_effect = ValueError('No free IPs left in 10.0.0.0/24')

        r = self.client.post(
            '/api/peers',
            data=json.dumps({
                'name': 'newpeer',
                'public_key': 'PUBKEY==',
                'password': 'verysecret123',
            }),
            content_type='application/json',
        )
        self.assertEqual(r.status_code, 409)
        data = json.loads(r.data)
        self.assertIn('No free IPs', data['error'])


class TestClearReinstallFlag(unittest.TestCase):
    """POST /api/peers/<name>/clear-reinstall"""

    def setUp(self):
        app.config['TESTING'] = True
        self.client = app.test_client()

    @patch('app.peer_registry')
    def test_clear_reinstall_returns_200_on_success(self, mock_reg):
        mock_reg.clear_reinstall_flag.return_value = True
        r = self.client.post('/api/peers/alice/clear-reinstall')
        self.assertEqual(r.status_code, 200)
        data = json.loads(r.data)
        self.assertIn('message', data)

    @patch('app.peer_registry')
    def test_clear_reinstall_calls_registry_with_peer_name(self, mock_reg):
        mock_reg.clear_reinstall_flag.return_value = True
        self.client.post('/api/peers/bob/clear-reinstall')
        mock_reg.clear_reinstall_flag.assert_called_once_with('bob')

    @patch('app.peer_registry')
    def test_clear_reinstall_returns_500_when_exception_raised(self, mock_reg):
        mock_reg.clear_reinstall_flag.side_effect = Exception('peer not found')
        r = self.client.post('/api/peers/ghost/clear-reinstall')
        self.assertEqual(r.status_code, 500)
        data = json.loads(r.data)
        self.assertIn('error', data)


class TestIpUpdate(unittest.TestCase):
    """POST /api/ip-update"""

    def setUp(self):
        app.config['TESTING'] = True
        self.client = app.test_client()

    @patch('app.routing_manager')
    @patch('app.peer_registry')
    def test_ip_update_returns_200_on_success(self, mock_reg, mock_rm):
        mock_reg.update_peer_ip.return_value = True
        mock_rm.update_peer_ip.return_value = None

        r = self.client.post(
            '/api/ip-update',
            data=json.dumps({'peer': 'alice', 'ip': '10.0.0.99'}),
            content_type='application/json',
        )
        self.assertEqual(r.status_code, 200)
        data = json.loads(r.data)
        self.assertIn('message', data)

    @patch('app.peer_registry')
    def test_ip_update_returns_400_when_peer_field_missing(self, mock_reg):
        r = self.client.post(
            '/api/ip-update',
            data=json.dumps({'ip': '10.0.0.99'}),
            content_type='application/json',
        )
        self.assertEqual(r.status_code, 400)
        data = json.loads(r.data)
        self.assertIn('error', data)
        mock_reg.update_peer_ip.assert_not_called()

    @patch('app.peer_registry')
    def test_ip_update_returns_400_when_ip_field_missing(self, mock_reg):
        r = self.client.post(
            '/api/ip-update',
            data=json.dumps({'peer': 'alice'}),
            content_type='application/json',
        )
        self.assertEqual(r.status_code, 400)
        data = json.loads(r.data)
        self.assertIn('error', data)
        mock_reg.update_peer_ip.assert_not_called()

    @patch('app.peer_registry')
    def test_ip_update_returns_400_when_no_body(self, mock_reg):
        r = self.client.post('/api/ip-update')
        self.assertEqual(r.status_code, 400)
        self.assertIn('error', json.loads(r.data))

    @patch('app.peer_registry')
    def test_ip_update_returns_404_when_peer_not_found(self, mock_reg):
        mock_reg.update_peer_ip.return_value = False
        r = self.client.post(
            '/api/ip-update',
            data=json.dumps({'peer': 'ghost', 'ip': '10.0.0.50'}),
            content_type='application/json',
        )
        self.assertEqual(r.status_code, 404)
        data = json.loads(r.data)
        self.assertIn('error', data)

    @patch('app.routing_manager')
    @patch('app.peer_registry')
    def test_ip_update_calls_registry_with_correct_args(self, mock_reg, mock_rm):
        mock_reg.update_peer_ip.return_value = True
        mock_rm.update_peer_ip.return_value = None

        self.client.post(
            '/api/ip-update',
            data=json.dumps({'peer': 'alice', 'ip': '10.0.0.5'}),
            content_type='application/json',
        )
        mock_reg.update_peer_ip.assert_called_once_with('alice', '10.0.0.5')


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