"""
Peer access update E2E tests.

Verifies that editing a peer's service_access, internet_access, and peer_access
settings via PUT /api/peers/<name> is persisted and reflected in the live
iptables and CoreDNS state immediately after the call returns.

Run against a live cell:
    PIC_HOST=localhost pytest tests/e2e/api/test_peer_access_update.py -v
"""
import time
import subprocess
import pytest

from helpers.api_client import PicAPIClient


# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

def _get_peer(admin_client, name: str) -> dict:
    r = admin_client.get(f'/api/peers/{name}')
    assert r.status_code == 200, f'GET /api/peers/{name} failed: {r.status_code} {r.text}'
    return r.json()


def _update_peer(admin_client, name: str, **fields) -> dict:
    r = admin_client.put(f'/api/peers/{name}', json=fields)
    assert r.status_code == 200, f'PUT /api/peers/{name} failed: {r.status_code} {r.text}'
    return r.json()


def _wg_forward_rules(admin_client) -> str:
    """Return raw iptables FORWARD rules from inside the WireGuard container."""
    r = admin_client.post('/api/debug/iptables-forward', json={})
    if r.status_code == 200:
        return r.text
    # Fallback: read directly via docker exec (only works on the same host)
    try:
        result = subprocess.run(
            ['docker', 'exec', 'cell-wireguard', 'iptables', '-L', 'FORWARD', '-n', '--line-numbers'],
            capture_output=True, text=True, timeout=5
        )
        return result.stdout
    except Exception:
        return ''


def _corefile_content(admin_client) -> str:
    """Return the current Corefile content via the API or direct read."""
    r = admin_client.get('/api/network/dns/corefile')
    if r.status_code == 200:
        return r.text
    # Fallback: read from the mapped config path
    try:
        with open('/home/roof/pic/config/dns/Corefile') as f:
            return f.read()
    except Exception:
        return ''


# ---------------------------------------------------------------------------
# service_access update tests
# ---------------------------------------------------------------------------

class TestServiceAccessUpdate:

    def test_restrict_all_services_creates_drop_rule(self, make_peer, admin_client):
        """Setting service_access=[] creates a DROP rule to Caddy for the peer."""
        peer = make_peer('e2etest-svc-drop')
        peer_ip = peer['ip']

        _update_peer(admin_client, peer['name'],
                     internet_access=True,
                     service_access=[],
                     peer_access=True)

        rules = _wg_forward_rules(admin_client)
        assert rules, 'Could not read iptables rules'
        # There should be a DROP rule for this peer IP targeting Caddy port 80
        assert 'DROP' in rules and peer_ip.replace('.', '.') in rules, (
            f'Expected DROP rule for {peer_ip} after service_access=[], '
            f'but rules show:\n{rules}'
        )

    def test_allow_some_services_creates_accept_rule(self, make_peer, admin_client):
        """Setting service_access=['calendar'] keeps ACCEPT to Caddy; ACL blocks others."""
        peer = make_peer('e2etest-svc-partial', service_access=[])
        peer_ip = peer['ip']

        # Start with no services, then grant calendar only
        _update_peer(admin_client, peer['name'],
                     internet_access=True,
                     service_access=['calendar'],
                     peer_access=True)

        rules = _wg_forward_rules(admin_client)
        assert rules, 'Could not read iptables rules'
        assert 'ACCEPT' in rules, (
            f'Expected ACCEPT rule for {peer_ip} after service_access=[calendar], '
            f'got:\n{rules}'
        )

    def test_service_access_reflected_in_peer_registry(self, make_peer, admin_client):
        """Updated service_access is persisted in the peer registry."""
        peer = make_peer('e2etest-svc-persist',
                         service_access=['calendar', 'files', 'mail', 'webdav'])

        _update_peer(admin_client, peer['name'],
                     internet_access=True,
                     service_access=['calendar'],
                     peer_access=True)

        stored = _get_peer(admin_client, peer['name'])
        assert stored.get('service_access') == ['calendar'], (
            f"Expected service_access=['calendar'] in registry, got: {stored.get('service_access')}"
        )

    def test_blocked_service_appears_in_corefile_acl(self, make_peer, admin_client):
        """Blocked services for a peer appear in the CoreDNS Corefile ACL."""
        peer = make_peer('e2etest-svc-acl', service_access=['calendar', 'files', 'mail', 'webdav'])
        peer_ip = peer['ip']

        # Block files and webdav
        _update_peer(admin_client, peer['name'],
                     internet_access=True,
                     service_access=['calendar', 'mail'],
                     peer_access=True)

        # Small delay for CoreDNS reload to process SIGUSR1
        time.sleep(1)

        corefile = _corefile_content(admin_client)
        assert corefile, 'Could not read Corefile'
        assert f'block net {peer_ip}/32' in corefile, (
            f'Expected block rule for {peer_ip} in Corefile after removing files/webdav. '
            f'Corefile:\n{corefile}'
        )

    def test_fully_allowed_peer_has_no_acl_block(self, make_peer, admin_client):
        """Peer with all services allowed has no ACL block entry in Corefile."""
        peer = make_peer('e2etest-svc-full', service_access=['calendar'])
        peer_ip = peer['ip']

        # Grant all services
        _update_peer(admin_client, peer['name'],
                     internet_access=True,
                     service_access=['calendar', 'files', 'mail', 'webdav'],
                     peer_access=True)

        time.sleep(1)
        corefile = _corefile_content(admin_client)
        assert f'block net {peer_ip}/32' not in corefile, (
            f'No ACL block expected for fully-allowed peer {peer_ip}, but found one. '
            f'Corefile:\n{corefile}'
        )

    def test_multiple_peers_blocked_from_same_service_in_single_acl_block(
        self, make_peer, admin_client
    ):
        """Two peers blocked from the same service share one acl block (not separate blocks)."""
        peer_a = make_peer('e2etest-svc-multi-a',
                           service_access=['calendar', 'files', 'mail', 'webdav'])
        peer_b = make_peer('e2etest-svc-multi-b',
                           service_access=['calendar', 'files', 'mail', 'webdav'])

        # Block both from files
        _update_peer(admin_client, peer_a['name'],
                     service_access=['calendar', 'mail', 'webdav'])
        _update_peer(admin_client, peer_b['name'],
                     service_access=['calendar', 'mail', 'webdav'])

        time.sleep(1)
        corefile = _corefile_content(admin_client)
        assert corefile, 'Could not read Corefile'

        # Count how many acl blocks exist for the files service
        domain = corefile.split('forward . ')[0].strip().rstrip('{').strip()
        # Find acl blocks for files
        acl_files_count = corefile.count('acl files.')
        assert acl_files_count == 1, (
            f'Expected exactly 1 acl block for files (both peers merged), '
            f'got {acl_files_count}. Corefile:\n{corefile}'
        )
        assert peer_a['ip'] in corefile, f"peer_a IP {peer_a['ip']} not in Corefile ACL"
        assert peer_b['ip'] in corefile, f"peer_b IP {peer_b['ip']} not in Corefile ACL"


# ---------------------------------------------------------------------------
# internet_access update tests
# ---------------------------------------------------------------------------

class TestInternetAccessUpdate:

    def test_disable_internet_access_sets_config_reinstall_flag(self, make_peer, admin_client):
        """Changing internet_access sets config_needs_reinstall on the peer."""
        peer = make_peer('e2etest-inet-flag')

        r = _update_peer(admin_client, peer['name'],
                         internet_access=False,
                         service_access=['calendar', 'files', 'mail', 'webdav'])

        assert r.get('config_changed') is True, (
            f'Expected config_changed=True when internet_access changes, got: {r}'
        )
        stored = _get_peer(admin_client, peer['name'])
        assert stored.get('internet_access') is False
        assert stored.get('config_needs_reinstall') is True

    def test_internet_access_persisted(self, make_peer, admin_client):
        peer = make_peer('e2etest-inet-persist')
        _update_peer(admin_client, peer['name'], internet_access=False,
                     service_access=['calendar', 'files', 'mail', 'webdav'])
        stored = _get_peer(admin_client, peer['name'])
        assert stored.get('internet_access') is False


# ---------------------------------------------------------------------------
# peer_access update tests
# ---------------------------------------------------------------------------

class TestPeerAccessUpdate:

    def test_peer_access_persisted(self, make_peer, admin_client):
        peer = make_peer('e2etest-peer-access')
        _update_peer(admin_client, peer['name'],
                     internet_access=True,
                     service_access=['calendar', 'files', 'mail', 'webdav'],
                     peer_access=False)
        stored = _get_peer(admin_client, peer['name'])
        assert stored.get('peer_access') is False

    def test_re_enabling_peer_access_persisted(self, make_peer, admin_client):
        peer = make_peer('e2etest-peer-reenable')
        _update_peer(admin_client, peer['name'], peer_access=False,
                     service_access=['calendar', 'files', 'mail', 'webdav'])
        _update_peer(admin_client, peer['name'], peer_access=True,
                     service_access=['calendar', 'files', 'mail', 'webdav'])
        stored = _get_peer(admin_client, peer['name'])
        assert stored.get('peer_access') is True