import os
import systemd.dbus
import dbus
from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel
from typing import List

app = FastAPI(title="NetMapper Agent", version="0.1.0")

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # da limitare in produzione
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

ALLOWED_SERVICES = [
    "netmapper-frontend.service",
    "netmapper-backend.service",
    "netmapper-worker.service",
]

class ServiceInfo(BaseModel):
    name: str
    active_state: str
    sub_state: str
    loaded: str
    pid: int | None = None

class ActionRequest(BaseModel):
    mode: str = "sync"

def get_unit(name: str):
    bus = dbus.SystemBus()
    systemd = bus.get_object('org.freedesktop.systemd1', '/org/freedesktop/systemd1')
    manager = dbus.Interface(systemd, 'org.freedesktop.systemd1.Manager')
    unit_path = manager.GetUnit(name)
    unit = bus.get_object('org.freedesktop.systemd1', str(unit_path))
    props = dbus.Interface(unit, 'org.freedesktop.DBus.Properties')
    return props.GetAll('org.freedesktop.systemd1.Unit')

def refresh_dbus():
    bus = dbus.SystemBus()
    systemd = bus.get_object('org.freedesktop.systemd1', '/org/freedesktop/systemd1')
    manager = dbus.Interface(systemd, 'org.freedesktop.systemd1.Manager')
    return manager

@app.get("/health")
def health():
    return {"status": "ok"}

@app.get("/services", response_model=List[ServiceInfo])
def list_services():
    bus = dbus.SystemBus()
    systemd = bus.get_object('org.freedesktop.systemd1', '/org/freedesktop/systemd1')
    manager = dbus.Interface(systemd, 'org.freedesktop.systemd1.Manager')
    units = manager.ListUnits()
    result = []
    for u in units:
        name = u[0]
        if name not in ALLOWED_SERVICES:
            continue
        result.append(ServiceInfo(
            name=name,
            active_state=u[3],
            sub_state=u[4],
            loaded=u[2],
            pid=None,
        ))
    return result

@app.get("/services/{name}")
def get_service(name: str):
    if name not in ALLOWED_SERVICES:
        raise HTTPException(status_code=403, detail="Service not allowed")
    props = get_unit(name)
    pid = None
    if "MainPID" in props:
        pid = int(props["MainPID"]) or None
    return ServiceInfo(
        name=name,
        active_state=str(props.get("ActiveState", "unknown")),
        sub_state=str(props.get("SubState", "unknown")),
        loaded=str(props.get("LoadState", "unknown")),
        pid=pid,
    )

@app.post("/services/{name}/start")
def start_service(name: str):
    if name not in ALLOWED_SERVICES:
        raise HTTPException(status_code=403, detail="Service not allowed")
    manager = refresh_dbus()
    job = manager.StartUnit(name, "replace")
    return {"job": str(job), "service": name, "action": "start"}

@app.post("/services/{name}/stop")
def stop_service(name: str):
    if name not in ALLOWED_SERVICES:
        raise HTTPException(status_code=403, detail="Service not allowed")
    manager = refresh_dbus()
    job = manager.StopUnit(name, "replace")
    return {"job": str(job), "service": name, "action": "stop"}

@app.post("/services/{name}/restart")
def restart_service(name: str):
    if name not in ALLOWED_SERVICES:
        raise HTTPException(status_code=403, detail="Service not allowed")
    manager = refresh_dbus()
    job = manager.RestartUnit(name, "replace")
    return {"job": str(job), "service": name, "action": "restart"}