"""Service de surveillance des ressources système du Raspberry Pi."""

from __future__ import annotations

import logging
import subprocess
from pathlib import Path

try:
    import psutil
    HAS_PSUTIL = True
except ImportError:
    HAS_PSUTIL = False
    logging.warning("psutil non disponible — stats système limitées")

logger = logging.getLogger(__name__)


class SystemService:
    def get_stats(self) -> dict:
        stats: dict = {}

        if not HAS_PSUTIL:
            return {"error": "psutil non installé"}

        # CPU
        stats["cpu_percent"] = psutil.cpu_percent(interval=None)

        # RAM
        mem = psutil.virtual_memory()
        stats["ram_total_mb"] = round(mem.total / 1024 / 1024)
        stats["ram_used_mb"] = round(mem.used / 1024 / 1024)
        stats["ram_percent"] = mem.percent
        stats["ram_available_mb"] = round(mem.available / 1024 / 1024)

        # Disque (racine)
        disk = psutil.disk_usage("/")
        stats["disk_total_gb"] = round(disk.total / 1024 ** 3, 1)
        stats["disk_used_gb"] = round(disk.used / 1024 ** 3, 1)
        stats["disk_percent"] = disk.percent

        # Température CPU (Raspberry Pi)
        stats["cpu_temp"] = self._get_cpu_temp()

        # Uptime
        import time
        boot_time = psutil.boot_time()
        uptime_sec = int(time.time() - boot_time)
        stats["uptime"] = self._format_uptime(uptime_sec)

        return stats

    def _get_cpu_temp(self) -> float | None:
        # Méthode 1 : fichier thermal du Pi
        try:
            temp_path = Path("/sys/class/thermal/thermal_zone0/temp")
            if temp_path.exists():
                return round(int(temp_path.read_text().strip()) / 1000, 1)
        except Exception:
            pass

        # Méthode 2 : vcgencmd (Pi OS)
        try:
            result = subprocess.run(
                ["vcgencmd", "measure_temp"],
                capture_output=True, text=True, timeout=3
            )
            if result.returncode == 0:
                # output: "temp=47.0'C"
                val = result.stdout.strip().replace("temp=", "").replace("'C", "")
                return float(val)
        except Exception:
            pass

        # Méthode 3 : psutil sensors (si disponible)
        if hasattr(psutil, "sensors_temperatures"):
            try:
                temps = psutil.sensors_temperatures()
                if temps:
                    first = next(iter(temps.values()))
                    if first:
                        return round(first[0].current, 1)
            except Exception:
                pass

        return None

    def _format_uptime(self, seconds: int) -> str:
        days = seconds // 86400
        hours = (seconds % 86400) // 3600
        minutes = (seconds % 3600) // 60
        if days > 0:
            return f"{days}j {hours:02d}h {minutes:02d}m"
        return f"{hours:02d}h {minutes:02d}m"

    def get_services_status(self) -> list[dict]:
        """Vérifie le statut des services systemd utiles."""
        services = [
            ("photobooth-app", "Photobooth App"),
            ("jh-photomaton", "JH Photomaton"),
            ("cups", "CUPS (Impression)"),
        ]
        result = []
        for svc_name, label in services:
            active = self._is_service_active(svc_name)
            result.append({"name": svc_name, "label": label, "active": active})
        return result

    def _is_service_active(self, service: str) -> bool:
        try:
            r = subprocess.run(
                ["systemctl", "is-active", service],
                capture_output=True, text=True, timeout=3
            )
            return r.stdout.strip() == "active"
        except Exception:
            return False