"""Audio processing engine."""

import asyncio
import logging
import threading
import time
import warnings
from typing import List, Optional, Union

import numpy as np
import soundcard as sc

from pymicro_wakeword import MicroWakeWord, MicroWakeWordFeatures
from pyopen_wakeword import OpenWakeWord, OpenWakeWordFeatures

from .models import ServerState

_LOGGER = logging.getLogger(__name__)

# Suppress the "log(0)" warning from pymicro_wakeword
warnings.filterwarnings("ignore", category=RuntimeWarning, module="pymicro_wakeword")


class AudioEngine:
    def __init__(self, state: ServerState, mic, block_size: int):
        self.state = state
        self.mic = mic
        self.block_size = block_size
        self._thread: Optional[threading.Thread] = None

    def start(self):
        """Starts the audio processing thread."""
        self._thread = threading.Thread(
            target=self._process_audio,
            daemon=True,
            name="AudioEngineThread"
        )
        self._thread.start()

    def stop(self):
        """Stops the audio processing thread."""
        self.state.shutdown = True
        # Ensure thread wakes up if waiting
        self.state.mic_muted_event.set()
        if self._thread:
            self._thread.join()

    def _process_audio(self):
        """Main audio processing loop."""
        _LOGGER.debug("Audio engine started.")
        
        micro_features = MicroWakeWordFeatures()
        oww_features: Optional[OpenWakeWordFeatures] = None
        
        wake_words: List[Union[MicroWakeWord, OpenWakeWord]] = []
        micro_inputs: List[np.ndarray] = []
        oww_inputs: List[np.ndarray] = []
        has_oww = False
        last_active: Optional[float] = None
        
        try:
            while True:
                # --- Handle Mute State ---
                if not self.state.mic_muted_event.is_set():
                    _LOGGER.debug("Audio thread muted. Waiting...")
                    self.state.mic_muted_event.wait()
                    
                    if self.state.shutdown:
                        return

                    # Unmuted: Clear buffers and prepare
                    _LOGGER.debug("Audio thread unmuted. Flushing...")
                    micro_features.reset()
                    if oww_features is not None:
                        oww_features.reset()
                    
                    # FIX: Allow immediate activation (don't set to 'now')
                    last_active = None 
                    
                    # Flush hardware buffer
                    try:
                        with self.mic.recorder(samplerate=16000, channels=1, blocksize=self.block_size) as mic_in:
                            mic_in.flush()
                    except Exception as e:
                        _LOGGER.warning("Error flushing mic: %s", e)
                
                if self.state.shutdown:
                    return
                
                # --- Main Recording Loop ---
                _LOGGER.debug("Opening audio input device: %s", self.mic.name)
                with self.mic.recorder(samplerate=16000, channels=1, blocksize=self.block_size) as mic_in:
                    while self.state.mic_muted_event.is_set():
                        if self.state.shutdown:
                            return 
                        
                        audio_chunk_array = mic_in.record(self.block_size).reshape(-1)
                        audio_chunk = (
                            (np.clip(audio_chunk_array, -1.0, 1.0) * 32767.0)
                            .astype("<i2")
                            .tobytes()
                        )

                        if self.state.satellite is None:
                            time.sleep(0.01)
                            continue
                        
                        # Update active wake words if changed
                        if (not wake_words) or (self.state.wake_words_changed):
                            self.state.wake_words_changed = False
                            wake_words = [
                                ww for ww in self.state.wake_words.values() 
                                if ww.id in self.state.active_wake_words
                            ]
                            has_oww = any(isinstance(ww, OpenWakeWord) for ww in wake_words)
                            
                            if has_oww and (oww_features is None):
                                _LOGGER.debug("Initializing OpenWakeWord features...")
                                oww_features = OpenWakeWordFeatures.from_builtin()
                        
                        try:
                            # Feature extraction
                            micro_inputs.clear()
                            micro_inputs.extend(micro_features.process_streaming(audio_chunk))
                            
                            if has_oww and oww_features:
                                oww_inputs.clear()
                                oww_inputs.extend(oww_features.process_streaming(audio_chunk))
                            
                            # Detection
                            for wake_word in wake_words:
                                activated = False
                                if isinstance(wake_word, MicroWakeWord):
                                    if any(wake_word.process_streaming(mi) for mi in micro_inputs): 
                                        activated = True
                                elif isinstance(wake_word, OpenWakeWord):
                                    if any(p > 0.5 for oi in oww_inputs for p in wake_word.process_streaming(oi)): 
                                        activated = True
                                
                                if activated:
                                    now = time.monotonic()
                                    if (last_active is None) or ((now - last_active) > self.state.refractory_seconds):
                                        self.state.loop.call_soon_threadsafe(self.state.satellite.wakeup, wake_word)
                                        last_active = now
                            
                            # Stop word detection
                            stopped = False
                            for micro_input in micro_inputs:
                                if self.state.stop_word.process_streaming(micro_input):
                                    stopped = True

                            if stopped and (self.state.stop_word.id in self.state.active_wake_words):
                                self.state.loop.call_soon_threadsafe(self.state.satellite.stop)
                                
                            # Pass audio to satellite (for voice streaming)
                            self.state.loop.call_soon_threadsafe(self.state.satellite.handle_audio, audio_chunk)

                        except Exception: 
                            _LOGGER.exception("Unexpected error handling audio")
        
        except Exception as e:
            _LOGGER.critical("A soundcard error occurred: %s", e)
            self.state.loop.call_soon_threadsafe(self.state.loop.stop)