"""
Call Manager — Active call state tracking and event bus.

Central nervous system of the gateway. Tracks all active calls,
publishes events, and coordinates between SIP engine and services.
"""

import asyncio
import logging
import uuid
from collections.abc import AsyncIterator
from datetime import datetime
from typing import Optional

from core.event_bus import EventBus, EventSubscription
from models.call import ActiveCall, AudioClassification, CallMode, CallStatus, ClassificationResult
from models.events import EventType, GatewayEvent

logger = logging.getLogger(__name__)


class CallManager:
    """
    Manages all active calls and their state.

    The single source of truth for what's happening on the gateway.
    """

    def __init__(self, event_bus: EventBus):
        self.event_bus = event_bus
        self._active_calls: dict[str, ActiveCall] = {}
        self._call_legs: dict[str, str] = {}  # SIP leg ID -> call ID mapping

    # ================================================================
    # Call Lifecycle
    # ================================================================

    async def create_call(
        self,
        remote_number: str,
        mode: CallMode = CallMode.DIRECT,
        intent: Optional[str] = None,
        call_flow_id: Optional[str] = None,
        device: Optional[str] = None,
        services: Optional[list[str]] = None,
    ) -> ActiveCall:
        """Create a new call and track it."""
        call_id = f"call_{uuid.uuid4().hex[:12]}"

        call = ActiveCall(
            id=call_id,
            remote_number=remote_number,
            mode=mode,
            intent=intent,
            call_flow_id=call_flow_id,
            device=device,
            services=services or [],
        )

        self._active_calls[call_id] = call

        await self.event_bus.publish(GatewayEvent(
            type=EventType.CALL_INITIATED,
            call_id=call_id,
            data={"number": remote_number, "mode": mode.value, "intent": intent},
            message=f"📞 Calling {remote_number} ({mode.value})",
        ))

        return call

    async def update_status(self, call_id: str, status: CallStatus) -> None:
        """Update a call's status and publish event."""
        call = self._active_calls.get(call_id)
        if not call:
            logger.warning(f"Cannot update status: call {call_id} not found")
            return

        old_status = call.status
        call.status = status

        # Track timing milestones
        if status == CallStatus.CONNECTED and not call.connected_at:
            call.connected_at = datetime.now()
        elif status == CallStatus.ON_HOLD:
            call.hold_started_at = datetime.now()
        elif status == CallStatus.HUMAN_DETECTED:
            call.hold_started_at = None  # Stop counting hold time

        # Map status to event type
        event_map = {
            CallStatus.RINGING: EventType.CALL_RINGING,
            CallStatus.CONNECTED: EventType.CALL_CONNECTED,
            CallStatus.NAVIGATING_IVR: EventType.IVR_STEP,
            CallStatus.ON_HOLD: EventType.HOLD_DETECTED,
            CallStatus.HUMAN_DETECTED: EventType.HUMAN_DETECTED,
            CallStatus.TRANSFERRING: EventType.TRANSFER_STARTED,
            CallStatus.BRIDGED: EventType.TRANSFER_COMPLETE,
            CallStatus.COMPLETED: EventType.CALL_ENDED,
            CallStatus.FAILED: EventType.CALL_FAILED,
        }

        event_type = event_map.get(status, EventType.CALL_CONNECTED)

        await self.event_bus.publish(GatewayEvent(
            type=event_type,
            call_id=call_id,
            data={
                "old_status": old_status.value,
                "new_status": status.value,
                "duration": call.duration,
                "hold_time": call.hold_time,
            },
            message=f"Call {call_id}: {old_status.value} → {status.value}",
        ))

    async def add_classification(
        self, call_id: str, result: ClassificationResult
    ) -> None:
        """Add an audio classification result to a call."""
        call = self._active_calls.get(call_id)
        if not call:
            return

        call.current_classification = result.audio_type
        call.classification_history.append(result)

        await self.event_bus.publish(GatewayEvent(
            type=EventType.AUDIO_CLASSIFIED,
            call_id=call_id,
            data={
                "audio_type": result.audio_type.value,
                "confidence": result.confidence,
            },
            message=f"🎵 Audio: {result.audio_type.value} ({result.confidence:.0%})",
        ))

    async def add_transcript(self, call_id: str, text: str) -> None:
        """Add a transcript chunk to a call."""
        call = self._active_calls.get(call_id)
        if not call:
            return

        call.transcript_chunks.append(text)

        await self.event_bus.publish(GatewayEvent(
            type=EventType.TRANSCRIPT_CHUNK,
            call_id=call_id,
            data={"text": text},
            message=f"📝 '{text[:80]}...' " if len(text) > 80 else f"📝 '{text}'",
        ))

    async def end_call(self, call_id: str, status: CallStatus = CallStatus.COMPLETED) -> Optional[ActiveCall]:
        """End a call and remove from active tracking."""
        call = self._active_calls.pop(call_id, None)
        if call:
            call.status = status
            await self.event_bus.publish(GatewayEvent(
                type=EventType.CALL_ENDED,
                call_id=call_id,
                data={
                    "duration": call.duration,
                    "hold_time": call.hold_time,
                    "final_status": status.value,
                },
                message=f"📵 Call ended: {call.remote_number} ({call.duration}s, hold: {call.hold_time}s)",
            ))
        return call

    # ================================================================
    # Leg Mapping
    # ================================================================

    def map_leg(self, sip_leg_id: str, call_id: str) -> None:
        """Map a SIP leg ID to a call ID."""
        self._call_legs[sip_leg_id] = call_id

    def get_call_for_leg(self, sip_leg_id: str) -> Optional[ActiveCall]:
        """Look up which call a SIP leg belongs to."""
        call_id = self._call_legs.get(sip_leg_id)
        if call_id:
            return self._active_calls.get(call_id)
        return None

    # ================================================================
    # Queries
    # ================================================================

    def get_call(self, call_id: str) -> Optional[ActiveCall]:
        """Get an active call by ID."""
        return self._active_calls.get(call_id)

    @property
    def active_calls(self) -> dict[str, ActiveCall]:
        """All active calls."""
        return dict(self._active_calls)

    @property
    def active_call_count(self) -> int:
        return len(self._active_calls)