# -*- coding: utf-8 -*-
"""
Capability Discovery für Satellites.

Ermöglicht die automatische Erkennung von Fähigkeiten
auf Satellites durch verschiedene Probe-Methoden.
"""

from __future__ import annotations

import asyncio
import logging
from abc import ABC, abstractmethod
from dataclasses import dataclass, field
from datetime import datetime, timedelta
from typing import Any, Awaitable, Callable

from trixy_core.satellite.capability.registry import (
    Capability,
    CapabilityInfo,
    CapabilityRegistry,
    CapabilityState,
)


@dataclass
class DiscoveryConfig:
    """Konfiguration für Capability-Discovery."""
    probe_timeout: float = 10.0         # Timeout für einzelne Probe
    probe_concurrency: int = 5          # Parallele Probes
    retry_failed: bool = True           # Fehlgeschlagene erneut prüfen
    retry_delay: float = 60.0           # Verzögerung vor Retry
    rediscover_interval: float = 3600.0  # Interval für erneute Discovery
    auto_discover: bool = True          # Automatische Discovery


@dataclass
class ProbeResult:
    """Ergebnis einer Capability-Probe."""
    capability_id: str
    success: bool
    state: CapabilityState
    error: str = ""
    parameters: dict[str, Any] = field(default_factory=dict)
    probe_time_ms: float = 0.0
    timestamp: datetime = field(default_factory=datetime.now)


class CapabilityProbe(ABC):
    """
    Abstrakte Basis für Capability-Probes.

    Eine Probe testet ob eine bestimmte Capability
    auf einem Satellite verfügbar ist.
    """

    def __init__(self, capability_info: CapabilityInfo) -> None:
        """
        Initialisiert die Probe.

        Args:
            capability_info: Capability die geprüft wird
        """
        self.capability_info = capability_info

    @property
    def capability_id(self) -> str:
        """ID der zu prüfenden Capability."""
        return self.capability_info.id

    @abstractmethod
    async def probe(
        self,
        satellite_id: str,
        send_func: Callable[[str, Any], Awaitable[Any]],
    ) -> ProbeResult:
        """
        Führt die Probe durch.

        Args:
            satellite_id: Zu prüfender Satellite
            send_func: Funktion zum Senden von Nachrichten

        Returns:
            Probe-Ergebnis
        """
        pass


class SimpleProbe(CapabilityProbe):
    """
    Einfache Probe die auf Ping-Antwort prüft.

    Sendet eine Capability-Query und erwartet eine
    Bestätigung vom Satellite.
    """

    def __init__(
        self,
        capability_info: CapabilityInfo,
        query_command: str = "capability_check",
    ) -> None:
        super().__init__(capability_info)
        self._query_command = query_command

    async def probe(
        self,
        satellite_id: str,
        send_func: Callable[[str, Any], Awaitable[Any]],
    ) -> ProbeResult:
        """Prüft Capability durch Query."""
        start = datetime.now()

        try:
            response = await send_func(
                satellite_id,
                {
                    "command": self._query_command,
                    "capability_id": self.capability_id,
                }
            )

            elapsed_ms = (datetime.now() - start).total_seconds() * 1000

            if response and response.get("available"):
                return ProbeResult(
                    capability_id=self.capability_id,
                    success=True,
                    state=CapabilityState.AVAILABLE,
                    parameters=response.get("parameters", {}),
                    probe_time_ms=elapsed_ms,
                )
            else:
                return ProbeResult(
                    capability_id=self.capability_id,
                    success=True,
                    state=CapabilityState.UNAVAILABLE,
                    error=response.get("error", ""),
                    probe_time_ms=elapsed_ms,
                )

        except Exception as e:
            elapsed_ms = (datetime.now() - start).total_seconds() * 1000
            return ProbeResult(
                capability_id=self.capability_id,
                success=False,
                state=CapabilityState.UNKNOWN,
                error=str(e),
                probe_time_ms=elapsed_ms,
            )


class CapabilityDiscovery:
    """
    Service für Capability-Discovery.

    Verwaltet Probes und führt automatische Erkennung
    von Satellite-Capabilities durch.

    Beispiel:
        discovery = CapabilityDiscovery(
            registry=registry,
            send_func=send_message,
        )

        # Probe registrieren
        discovery.register_probe(AudioInputProbe())

        # Discovery für Satellite durchführen
        results = await discovery.discover_satellite("sat-001")

        # Alle Satellites prüfen
        await discovery.discover_all()
    """

    def __init__(
        self,
        registry: CapabilityRegistry,
        send_func: Callable[[str, Any], Awaitable[Any]],
        config: DiscoveryConfig | None = None,
        logger: logging.Logger | None = None,
    ) -> None:
        """
        Initialisiert den Discovery-Service.

        Args:
            registry: Capability-Registry
            send_func: Funktion zum Senden an Satellites
            config: Discovery-Konfiguration
            logger: Logger-Instanz
        """
        self.registry = registry
        self._send_func = send_func
        self.config = config or DiscoveryConfig()
        self.logger = logger or logging.getLogger(__name__)

        self._probes: dict[str, CapabilityProbe] = {}
        self._last_discovery: dict[str, datetime] = {}
        self._discovery_task: asyncio.Task | None = None
        self._semaphore = asyncio.Semaphore(self.config.probe_concurrency)

    @property
    def probe_count(self) -> int:
        """Anzahl registrierter Probes."""
        return len(self._probes)

    def register_probe(self, probe: CapabilityProbe) -> None:
        """
        Registriert eine Capability-Probe.

        Args:
            probe: Probe-Instanz
        """
        self._probes[probe.capability_id] = probe

        # Capability-Definition registrieren
        self.registry.define_capability(probe.capability_info)

        self.logger.debug(f"Probe registriert: {probe.capability_id}")

    def unregister_probe(self, capability_id: str) -> bool:
        """Entfernt eine Probe."""
        if capability_id in self._probes:
            del self._probes[capability_id]
            return True
        return False

    async def _run_probe(
        self,
        satellite_id: str,
        probe: CapabilityProbe,
    ) -> ProbeResult:
        """Führt einzelne Probe mit Timeout aus."""
        async with self._semaphore:
            try:
                return await asyncio.wait_for(
                    probe.probe(satellite_id, self._send_func),
                    timeout=self.config.probe_timeout,
                )
            except asyncio.TimeoutError:
                return ProbeResult(
                    capability_id=probe.capability_id,
                    success=False,
                    state=CapabilityState.UNKNOWN,
                    error="Timeout",
                    probe_time_ms=self.config.probe_timeout * 1000,
                )

    async def discover_capability(
        self,
        satellite_id: str,
        capability_id: str,
    ) -> ProbeResult | None:
        """
        Prüft einzelne Capability auf Satellite.

        Args:
            satellite_id: Satellite-ID
            capability_id: Capability-ID

        Returns:
            Probe-Ergebnis oder None wenn keine Probe
        """
        probe = self._probes.get(capability_id)
        if not probe:
            return None

        result = await self._run_probe(satellite_id, probe)

        # Registry aktualisieren
        if result.success:
            cap = Capability(
                info=probe.capability_info,
                state=result.state,
                parameters=result.parameters,
            )
            self.registry.register(satellite_id, cap)

        return result

    async def discover_satellite(
        self,
        satellite_id: str,
        capabilities: list[str] | None = None,
    ) -> list[ProbeResult]:
        """
        Führt Discovery für einen Satellite durch.

        Args:
            satellite_id: Satellite-ID
            capabilities: Optional: Spezifische Capabilities

        Returns:
            Liste der Probe-Ergebnisse
        """
        probes_to_run = []

        if capabilities:
            probes_to_run = [
                self._probes[cid] for cid in capabilities
                if cid in self._probes
            ]
        else:
            probes_to_run = list(self._probes.values())

        if not probes_to_run:
            return []

        self.logger.info(
            f"Starte Discovery für {satellite_id} "
            f"({len(probes_to_run)} Probes)"
        )

        # Probes parallel ausführen
        tasks = [
            self._run_probe(satellite_id, probe)
            for probe in probes_to_run
        ]

        results = await asyncio.gather(*tasks, return_exceptions=True)

        # Ergebnisse verarbeiten
        probe_results: list[ProbeResult] = []
        for i, result in enumerate(results):
            probe = probes_to_run[i]

            if isinstance(result, Exception):
                probe_result = ProbeResult(
                    capability_id=probe.capability_id,
                    success=False,
                    state=CapabilityState.UNKNOWN,
                    error=str(result),
                )
            else:
                probe_result = result

            probe_results.append(probe_result)

            # Registry aktualisieren
            if probe_result.success:
                cap = Capability(
                    info=probe.capability_info,
                    state=probe_result.state,
                    parameters=probe_result.parameters,
                )
                self.registry.register(satellite_id, cap)

        # Discovery-Zeit speichern
        self._last_discovery[satellite_id] = datetime.now()

        # Statistik loggen
        available = sum(
            1 for r in probe_results
            if r.state == CapabilityState.AVAILABLE
        )
        self.logger.info(
            f"Discovery für {satellite_id} abgeschlossen: "
            f"{available}/{len(probe_results)} verfügbar"
        )

        return probe_results

    async def discover_all(
        self,
        satellite_ids: list[str],
        force: bool = False,
    ) -> dict[str, list[ProbeResult]]:
        """
        Führt Discovery für mehrere Satellites durch.

        Args:
            satellite_ids: Liste von Satellite-IDs
            force: Erneute Discovery auch wenn kürzlich durchgeführt

        Returns:
            Dict mit Ergebnissen pro Satellite
        """
        results: dict[str, list[ProbeResult]] = {}

        for sat_id in satellite_ids:
            # Prüfen ob erneute Discovery nötig
            if not force and sat_id in self._last_discovery:
                elapsed = (
                    datetime.now() - self._last_discovery[sat_id]
                ).total_seconds()
                if elapsed < self.config.rediscover_interval:
                    continue

            results[sat_id] = await self.discover_satellite(sat_id)

        return results

    async def start_auto_discovery(
        self,
        get_satellites_func: Callable[[], list[str]],
    ) -> None:
        """
        Startet automatische periodische Discovery.

        Args:
            get_satellites_func: Funktion die Satellite-IDs liefert
        """
        if self._discovery_task is not None:
            return

        async def discovery_loop():
            while True:
                try:
                    satellites = get_satellites_func()
                    await self.discover_all(satellites)
                except asyncio.CancelledError:
                    break
                except Exception as e:
                    self.logger.error(f"Auto-Discovery Fehler: {e}")

                await asyncio.sleep(self.config.rediscover_interval)

        self._discovery_task = asyncio.create_task(discovery_loop())

    async def stop_auto_discovery(self) -> None:
        """Stoppt automatische Discovery."""
        if self._discovery_task:
            self._discovery_task.cancel()
            try:
                await self._discovery_task
            except asyncio.CancelledError:
                pass
            self._discovery_task = None

    def needs_rediscovery(self, satellite_id: str) -> bool:
        """Prüft ob Satellite erneute Discovery benötigt."""
        if satellite_id not in self._last_discovery:
            return True

        elapsed = (
            datetime.now() - self._last_discovery[satellite_id]
        ).total_seconds()

        return elapsed >= self.config.rediscover_interval

    def get_stats(self) -> dict[str, Any]:
        """Liefert Discovery-Statistiken."""
        return {
            "probe_count": self.probe_count,
            "discovered_satellites": len(self._last_discovery),
            "auto_discovery_running": self._discovery_task is not None,
            "config": {
                "probe_timeout": self.config.probe_timeout,
                "probe_concurrency": self.config.probe_concurrency,
                "rediscover_interval": self.config.rediscover_interval,
            },
        }