extends Node

## AudioManager Singleton
## Zentrale Audio-Analyse für alle Lichteffekte
## Verhindert mehrfache Spectrum-Analyzer-Aufrufe pro Frame

# Frequenzbereiche
const BASS_RANGE = Vector2(20, 250)
const MID_RANGE = Vector2(250, 2000)
const HIGH_RANGE = Vector2(2000, 20000)

# Interner State
var audio_player: AudioStreamPlayer3D
var audio_spectrum: AudioEffectSpectrumAnalyzerInstance
var is_setup: bool = false

# Cache für Magnitude-Werte (wird einmal pro Frame berechnet)
var _magnitude_cache: Array[float] = [0.0, 0.0, 0.0, 0.0]  # [Bass, Mid, High, All]
var _last_frame: int = -1

func _ready():
	print("AudioManager: Singleton initialisiert")

## Setup mit AudioStreamPlayer3D
func setup(player: AudioStreamPlayer3D) -> bool:
	if is_setup and audio_player == player:
		return true  # Bereits korrekt eingerichtet
	
	audio_player = player
	
	if not audio_player:
		push_error("AudioManager: Kein AudioStreamPlayer3D übergeben!")
		return false
	
	# Setup Spectrum Analyzer
	var bus_index = AudioServer.get_bus_index(audio_player.bus)
	var has_spectrum = false
	
	# Prüfe, ob bereits ein Spectrum Analyzer vorhanden ist
	for i in range(AudioServer.get_bus_effect_count(bus_index)):
		if AudioServer.get_bus_effect(bus_index, i) is AudioEffectSpectrumAnalyzer:
			has_spectrum = true
			break
	
	# Falls nicht, füge einen hinzu
	if not has_spectrum:
		var spectrum = AudioEffectSpectrumAnalyzer.new()
		AudioServer.add_bus_effect(bus_index, spectrum)
		print("AudioManager: Spectrum Analyzer hinzugefügt zu Bus '%s'" % audio_player.bus)
	
	# Hole die Instanz
	for i in range(AudioServer.get_bus_effect_count(bus_index)):
		var effect = AudioServer.get_bus_effect(bus_index, i)
		if effect is AudioEffectSpectrumAnalyzer:
			audio_spectrum = AudioServer.get_bus_effect_instance(bus_index, i)
			break
	
	if not audio_spectrum:
		push_error("AudioManager: Konnte Spectrum Analyzer Instanz nicht holen!")
		return false
	
	is_setup = true
	print("AudioManager: Erfolgreich eingerichtet mit Bus '%s'" % audio_player.bus)
	return true

## Prüft, ob Audio gerade abgespielt wird
func is_playing() -> bool:
	return is_setup and audio_player and audio_player.playing

## Gibt ROHE Magnitude für Frequenzbereich zurück (ohne Verarbeitung)
## freq_range: 0=Bass, 1=Mitten, 2=Höhen, 3=Alle
func get_raw_magnitude(freq_range: int) -> float:
	if not is_setup or not audio_spectrum:
		return 0.0
	
	_update_cache_if_needed()
	return _magnitude_cache[clamp(freq_range, 0, 3)]

## Optional: Gibt Magnitude mit Standard-Verarbeitung zurück
func get_magnitude(freq_range: int, sensitivity: float = 1.0) -> float:
	var raw = get_raw_magnitude(freq_range)
	return clamp(raw * sensitivity, 0.0, 1.0)

## Interner Cache-Update (nur einmal pro Frame)
func _update_cache_if_needed():
	var current_frame = Engine.get_process_frames()
	
	# Bereits in diesem Frame berechnet?
	if _last_frame == current_frame:
		return
	
	_last_frame = current_frame
	
	# Berechne alle Frequenzbereiche
	if not audio_player.playing:
		_magnitude_cache = [0.0, 0.0, 0.0, 0.0]
		return
	
	_magnitude_cache[0] = _get_magnitude_for_range(BASS_RANGE)    # Bass
	_magnitude_cache[1] = _get_magnitude_for_range(MID_RANGE)     # Mitten
	_magnitude_cache[2] = _get_magnitude_for_range(HIGH_RANGE)    # Höhen
	_magnitude_cache[3] = (_magnitude_cache[0] + _magnitude_cache[1] + _magnitude_cache[2]) / 3.0  # Alle

## Berechnet Magnitude für einen Frequenzbereich
func _get_magnitude_for_range(freq_range: Vector2) -> float:
	if not audio_spectrum:
		return 0.0
	
	var from_hz = freq_range.x
	var to_hz = freq_range.y
	var magnitude_sum = 0.0
	var sample_count = 0
	
	# Sample alle 100Hz im Bereich
	for hz in range(int(from_hz), int(to_hz), 100):
		var magnitude = audio_spectrum.get_magnitude_for_frequency_range(hz, hz + 100)
		magnitude_sum += magnitude.length()
		sample_count += 1
	
	if sample_count > 0:
		return magnitude_sum / sample_count
	return 0.0

## Debug-Info
func get_debug_info() -> Dictionary:
	return {
		"is_setup": is_setup,
		"is_playing": is_playing(),
		"bass": _magnitude_cache[0],
		"mid": _magnitude_cache[1],
		"high": _magnitude_cache[2],
		"all": _magnitude_cache[3],
		"frame": _last_frame
	}