from __future__ import annotations

from fastapi import APIRouter, Depends
from sqlmodel import Session, select

from ..connectors.unraid import UnraidConnector
from ..core.redaction import redact_message
from ..db.models import AuditEvent, Connector
from ..db.session import get_session
from ..services.incident_service import count_open_incidents
from ..services.setup_service import apply_stored_connector_settings, list_connector_settings

router = APIRouter(prefix='/api/system')


def _gateway_health(unraid_status: str, portainer_status: str, open_incidents: int) -> str:
    core_statuses = {unraid_status, portainer_status}
    if core_statuses & {'missing_config', 'error', 'disconnected'}:
        return 'critical'
    if open_incidents > 0:
        return 'warning'
    return 'healthy'


def _latest_action_label(session: Session) -> str | None:
    event = session.exec(select(AuditEvent).order_by(AuditEvent.timestamp.desc())).first()
    if event is None:
        return None
    action = str(event.action_id or '').strip()
    target = str(event.target or '').strip()
    if not action:
        return None
    label = f'{action} -> {target}' if target else action
    return redact_message(label)[:120]


@router.get('/summary')
def system_summary(session: Session = Depends(get_session)):
    apply_stored_connector_settings(session)
    connectors = session.exec(select(Connector)).all()
    status_map = {connector.id: connector.status for connector in connectors}
    config_map = {item["connectorId"]: item for item in list_connector_settings(session)}

    portainer_config = config_map.get('portainer', {})
    portainer_status = 'missing_config' if portainer_config.get('missing') else status_map.get('portainer', 'disconnected')
    if portainer_status not in {'connected', 'missing_config', 'error', 'disconnected'}:
        portainer_status = 'disconnected'

    unraid_config = config_map.get('unraid', {})
    unraid_status = 'missing_config' if unraid_config.get('missing') else status_map.get('unraid', 'disconnected')
    if unraid_status not in {'connected', 'missing_config', 'error', 'disconnected'}:
        unraid_status = 'disconnected'

    unraid = UnraidConnector()
    server_info = unraid.get_server_info() if unraid.is_configured() else {'status': 'missing_config'}
    metrics = unraid.get_system_metrics() if unraid.is_configured() else {'status': 'missing_config'}
    cache = unraid.get_cache_status() if unraid.is_configured() else {'status': 'missing_config'}
    server = server_info.get('info', {}) if server_info.get('status') == 'ok' else {}
    cpu_usage = metrics.get('cpuUsage') if isinstance(metrics.get('cpuUsage'), int | float) else 0
    ram_usage = metrics.get('ramUsage') if isinstance(metrics.get('ramUsage'), int | float) else 0
    cache_usage = cache.get('cacheUsage') if cache.get('status') == 'ok' and isinstance(cache.get('cacheUsage'), int | float) else 0
    open_incidents = count_open_incidents(session)
    last_action = _latest_action_label(session)

    return {
        'gatewayHealth': _gateway_health(unraid_status, portainer_status, open_incidents),
        'unraidStatus': unraid_status,
        'portainerStatus': portainer_status,
        'maintenanceMode': False,
        'openIncidents': open_incidents,
        'lastAction': last_action,
        'uptime': str(server.get('uptime') or 'unknown'),
        'cpuUsage': int(cpu_usage),
        'ramUsage': int(ram_usage),
        'cacheUsage': int(cache_usage),
    }