Godot Audio Systems

class_name AudioAdaptiveMusicPlayer
extends Node

## Expert BPM-synced music transition manager.
## Handles horizontal re-sequencing on beat boundaries.

@export var bpm: float = 120.0
var beats_per_bar: int = 4
var current_player: AudioStreamPlayer

func transition_to(new_stream: AudioStream) -> void:
	var playback_pos = current_player.get_playback_position()
	var beat_duration = 60.0 / bpm
	var bar_duration = beat_duration * beats_per_bar
	
	# Wait for next bar before swapping
	var time_to_next_bar = bar_duration - fmod(playback_pos, bar_duration)
	await get_tree().create_timer(time_to_next_bar).timeout
	
	# Perform crossfade logic...
	pass

## Rule: Always sync transitions to bar boundaries for professional musicality.

class_name AudioBusDuckerLogic
extends Node

## Expert 'Sidechain' style Bus Ducking.
## Lowers music volume when a 'Hero' sound (SFX) is triggered.

@export var target_bus: String = "Music"
@export var trigger_bus: String = "Dialog"

func duck_bus(amount_db: float = -15.0, duration: float = 0.5) -> void:
	var bus_idx = AudioServer.get_bus_index(target_bus)
	var original_db = AudioServer.get_bus_volume_db(bus_idx)
	
	var tween = create_tween().set_trans(Tween.TRANS_SINE)
	tween.tween_method(func(v): AudioServer.set_bus_volume_db(bus_idx, v), original_db, amount_db, 0.1)
	tween.tween_interval(duration)
	tween.tween_method(func(v): AudioServer.set_bus_volume_db(bus_idx, v), amount_db, original_db, 0.5)

## Rule: Ducking is essential for clarity in narrative-heavy or loud combat games.

# skills/audio-systems/scripts/audio_bus_manager.gd
extends Node

## Audio Bus Manager Expert Pattern
## Advanced audio routing, ducking, and pool management.

class_name AudioBusManager

const BUS_MUSIC = "Music"
const BUS_SFX = "SFX"
const BUS_UI = "UI"
const BUS_VOICE = "Voice"

@export var sfx_pool_size := 32

var _sfx_pool: Array[AudioStreamPlayer] = []
var _music_players: Dictionary = {} # { "track_name": AudioStreamPlayer }

func _ready() -> void:
	_init_sfx_pool()

func _init_sfx_pool() -> void:
	for i in sfx_pool_size:
		var player := AudioStreamPlayer.new()
		player.bus = BUS_SFX
		player.finished.connect(func(): player.stop()) # Ensure cleaned up state
		add_child(player)
		_sfx_pool.append(player)

func play_sfx(stream: AudioStream, pitch_scale := 1.0, volume_db := 0.0) -> void:
	var player := _get_available_sfx_player()
	if player:
		player.stream = stream
		player.pitch_scale = pitch_scale
		player.volume_db = volume_db
		player.play()

func _get_available_sfx_player() -> AudioStreamPlayer:
	for player in _sfx_pool:
		if not player.playing:
			return player
	
	# Optional: Steal oldest voice if critical (not implemented here for simplicity)
	push_warning("SFX pool exhausted")
	return null

func play_music(stream: AudioStream, crossfade_duration := 2.0) -> void:
	# Crossfade logic would go here, utilizing a Tween to lower current track vol
	# and raise new track vol.
	
	var tween = create_tween()
	# ... (Implementation of crossfade omitted for brevity, but this is where it lives)
	pass

func duck_music_for_voice(ducking_amount := -10.0, duration := 0.5) -> void:
	var bus_idx := AudioServer.get_bus_index(BUS_MUSIC)
	var tween := create_tween()
	tween.tween_method(
		func(v): AudioServer.set_bus_volume_db(bus_idx, v),
		AudioServer.get_bus_volume_db(bus_idx),
		ducking_amount,
		duration
	)

func restore_music_volume(duration := 1.0) -> void:
	var bus_idx := AudioServer.get_bus_index(BUS_MUSIC)
	var tween := create_tween()
	tween.tween_method(
		func(v): AudioServer.set_bus_volume_db(bus_idx, v),
		AudioServer.get_bus_volume_db(bus_idx),
		0.0, # Target normal volume
		duration
	)

## EXPERT USAGE:
## AudioBusManager.play_sfx(preload("res://boom.wav"), 1.2)
## AudioBusManager.duck_music_for_voice()

class_name AudioEnvironmentalReverbZone
extends Area3D

## Expert Area-based reverb management.
## Dynamically modifies bus reverb parameters when entering the zone.

@export var reverb_index: int = 0
@export var room_size: float = 0.8

func _ready() -> void:
	body_entered.connect(_on_body_entered)

func _on_body_entered(body: Node) -> void:
	if body.is_in_group("Player"):
		var sfx_bus = AudioServer.get_bus_index("SFX")
		var reverb = AudioServer.get_bus_effect(sfx_bus, reverb_index) as AudioEffectReverb
		reverb.room_size = room_size

## Tip: Use multiple zones to smoothly transition a player between 'Cave' and 'Hall'.

class_name AudioFootstepSurfaceSelector
extends RayCast3D

## Expert multi-surface footstep selector.
## Detects floor type via Physics and picks the correct sound bank.

var surface_sounds: Dictionary = {
	"Stone": preload("res://audio/steps_stone.tres"),
	"Wood": preload("res://audio/steps_wood.tres")
}

func get_step_stream() -> AudioStream:
	if is_colliding():
		var collider = get_collider()
		# Expert: Use Groups or Metadata to identify surface type
		for group in surface_sounds.keys():
			if collider.is_in_group(group):
				return surface_sounds[group].get_random()
	return null

class_name InteractiveMusicManager
extends Node

## Expert manager for vertical music layering using AudioStreamSynchronized.
## Allows seamless crossfading between musical stems based on game intensity.

@export var music_player: AudioStreamPlayer

var _sync_stream: AudioStreamSynchronized

func _ready() -> void:
	if not music_player: return
	
	_sync_stream = music_player.stream as AudioStreamSynchronized
	if not _sync_stream:
		push_error("InteractiveMusicManager: AudioStreamPlayer must use an AudioStreamSynchronized resource.")
		return

## Fades a specific stem index to a target volume.
## stem_index matches the order in the AudioStreamSynchronized resource.
func fade_stem(index: int, target_db: float, duration: float = 2.0) -> void:
	if index >= _sync_stream.stream_count: return
	
	var current_vol = _sync_stream.get_sync_stream_volume(index)
	var tween = create_tween()
	
	tween.tween_method(
		func(v): _sync_stream.set_sync_stream_volume(index, v),
		current_vol,
		target_db,
		duration
	).set_trans(Tween.TRANS_SINE).set_ease(Tween.EASE_IN_OUT)

## Convenience method to mute all layers except the base.
func reset_to_base(base_index: int = 0) -> void:
	for i in range(_sync_stream.stream_count):
		var vol = 0.0 if i == base_index else -60.0
		fade_stem(i, vol, 1.0)

class_name AudioLinearVolumeInterpolator
extends Node

## Expert linear-to-db volume interpolation.
## Essential for smooth UI sliders that feel musically correct.

func set_linear_volume(bus_name: String, value: float) -> void:
	var bus_idx = AudioServer.get_bus_index(bus_name)
	var db_value = linear_to_db(value)
	AudioServer.set_bus_volume_db(bus_idx, db_value)

## Rule: Volume sliders must ALWAYS use 'linear_to_db'. Constant DB change = Logarithmic feel.

# skills/audio-systems/code/audio_manager.gd
extends Node

## AudioManager Singleton Expert Pattern
## Centralized system for sound pooling and bus management.

const MAX_POOL_SIZE = 32
var _pool: Array[AudioStreamPlayer] = []

func _ready() -> void:
    # 1. Initialize Sound Pool
    for i in range(MAX_POOL_SIZE):
        var player = AudioStreamPlayer.new()
        add_child(player)
        _pool.append(player)

func play_sfx(stream: AudioStream, bus: String = "SFX") -> void:
    # 2. Find Available Player
    var player = _find_available_player()
    if player:
        player.stream = stream
        player.bus = bus
        player.play()

func crossfade_music(to_stream: AudioStream, duration: float = 1.0) -> void:
    # 3. Dynamic Music Crossfading logic
    pass

func _find_available_player() -> AudioStreamPlayer:
    for player in _pool:
        if not player.playing:
            return player
    return null

## NEVER LIST:
## - NEVER play positional 3D audio on a node that dies.
## - Use 'AudioStreamPlayer3D' but parent it to the world root, 
##   setting its 'global_position' manually.

class_name AudioOcclusionRaycast
extends Node3D

## Expert Audio Occlusion logic.
## Dynamically applies attenuation_filter_cutoff_hz when the line-of-sight is blocked.

@export var audio_player: AudioStreamPlayer3D
@export var collision_mask: int = 1

const FREQ_CLEAR := 20500.0 # Effect disabled
const FREQ_OCCLUDED := 1200.0 # Muffled

var _active_tween: Tween

func _physics_process(_delta: float) -> void:
	if not audio_player.playing: return
	
	var camera = get_viewport().get_camera_3d()
	if not camera: return
	
	# Check line of sight
	var space = get_world_3d().direct_space_state
	var query = PhysicsRayQueryParameters3D.create(global_position, camera.global_position, collision_mask, [audio_player.get_rid()])
	var result = space.intersect_ray(query)
	
	var target_hz = FREQ_OCCLUDED if not result.is_empty() else FREQ_CLEAR
	
	if not is_equal_approx(audio_player.attenuation_filter_cutoff_hz, target_hz):
		_fade_to_freq(target_hz)

func _fade_to_freq(target: float) -> void:
	if _active_tween: _active_tween.kill()
	_active_tween = create_tween()
	_active_tween.tween_property(audio_player, "attenuation_filter_cutoff_hz", target, 0.25).set_trans(Tween.TRANS_SINE)

class_name AudioProceduralGeneratorSynth
extends Node

## Expert real-time procedural audio synthesizer.
## Pushes raw frames to an 'AudioStreamGeneratorPlayback'.

var playback: AudioStreamGeneratorPlayback
var sample_rate: float

func _ready() -> void:
	var generator = $AudioStreamPlayer.stream as AudioStreamGenerator
	sample_rate = generator.mix_rate
	playback = $AudioStreamPlayer.get_stream_playback()

func fill_buffer(frequency: float = 440.0) -> void:
	var phase = 0.0
	var increment = frequency / sample_rate
	var frames_to_fill = playback.get_frames_available()
	
	for i in range(frames_to_fill):
		var sample = sin(phase * TAU)
		playback.push_frame(Vector2(sample, sample))
		phase = fmod(phase + increment, 1.0)

## Rule: Always check 'get_frames_available()' before pushing to avoid buffer underrun.

class_name AudioReactiveVisualizer
extends Node

## Expert spectrum-driven visualizer.
## Extracts magnitude from frequency ranges (Bass/Mid/High).

var spectrum: AudioEffectSpectrumAnalyzerInstance

func _ready() -> void:
	spectrum = AudioServer.get_bus_effect_instance(0, 0) # Index 0 of Master Bus

func get_bass_magnitude() -> float:
	var mag = spectrum.get_magnitude_for_frequency_range(20, 150)
	return mag.length()

## Tip: Use 'magnitude' to drive shader uniforms or light energy for audio-reactivity.

# skills/audio-systems/code/audio_visualizer.gd
extends Node

## Real-Time FFT Visualization Expert Pattern
## Technical blueprints for driving visuals based on audio peaks.

@onready var spectrum = AudioServer.get_bus_effect_instance(0, 0) # Master bus, index 0

func _process(_delta: float) -> void:
    if not spectrum: return
    
    # 1. Capture Frequency Ranges
    var low = spectrum.get_magnitude_for_frequency_range(20, 150)
    var mid = spectrum.get_magnitude_for_frequency_range(150, 2000)
    var high = spectrum.get_magnitude_for_frequency_range(2000, 20000)
    
    # 2. Normalize and drive VEFX (Visual Effects)
    var energy = (low.length() + mid.length() + high.length()) / 3.0
    _update_world_lighting(energy)

func _update_world_lighting(power: float) -> void:
    # Expert: Drive a shader parameter or light energy
    # SceneRoot.set_shader_parameter("audio_pulse", power)
    pass

## WHY THIS WAY?
## Spectral analysis allows for organic, rhythm-synced gameplay 
## (e.g. lights flashing on the beat) without manual keyframing.

class_name AudioVoiceLimiterManager
extends Node

## Expert SFX instance limiter.
## Prevents 'Phasing' and 'Ear Bleed' by capping identical sound instances.

var active_counts: Dictionary = {}

func can_play(sound_id: String, limit: int = 5) -> bool:
	var count = active_counts.get(sound_id, 0)
	if count >= limit:
		return false
	
	active_counts[sound_id] = count + 1
	# Logic to decrement count when sound finishes...
	return true

## Rule: Limit weapons/explosions to 5-10 concurrent instances to maintain clarity.

class_name AudioVoicePoolManager
extends Node

## Expert Voice Pool Manager.
## Prioritizes 'Hero' sounds and implements voice stealing for background noise.

const MAX_VOICES = 32
var pool: Array[AudioStreamPlayer] = []
var active_voices: Array[AudioStreamPlayer] = []

func _ready() -> void:
	for i in range(MAX_VOICES):
		var p := AudioStreamPlayer.new()
		add_child(p)
		pool.append(p)

func play_sound(stream: AudioStream, priority: int = 0) -> void:
	# priority: 0 = background, 1 = standard, 2 = hero (never kills)
	var player = _get_available_player()
	if not player:
		player = _steal_voice()
	
	if player:
		player.stream = stream
		player.play()

func _get_available_player() -> AudioStreamPlayer:
	for p in pool:
		if not p.playing: return p
	return null

func _steal_voice() -> AudioStreamPlayer:
	# Basic logic: steal the oldest playing voice with priority 0.
	return pool[0] # Simplified logic for boilerplate

## Rule: Never exceed MAX_VOICES to avoid audio engine stutter/latency.

# interactive_music_graph.gd
# Expert pattern for non-linear, interactive music scoring.
# Grounded in Godot 4.x AudioStreamInteractive (available in 4.3+).

extends AudioStreamPlayer

class_name InteractiveMusicGraph

## Logic for transitioning between music states (e.g., Exploration to Combat).
func transition_to_state(state_name: String) -> void:
	if stream is AudioStreamInteractive:
		var interactive_stream := stream as AudioStreamInteractive
		# Find the clip index by name
		# In Godot 4.3+, you'd use the AudioStreamInteractive API directly.
		print("Interactive Music: Transitioning to '%s'" % state_name)
		# Placeholder for actual transition logic
	else:
		push_warning("Interactive Music: Stream is not an AudioStreamInteractive.")

## Expert Tip: Use 'switch_mode' (Beat, Bar, Transition) to ensure 
## musical continuity when changing states.

extends Node

class_name SubtitleSyncSystem

signal subtitle_show(text: String)
signal subtitle_hide()

@export var audio_player: AudioStreamPlayer

# Array of dictionaries: {"time": float, "text": String}
var _subtitle_track: Array[Dictionary] = []
var _current_index: int = -1

func start_dialogue(track: Array[Dictionary]) -> void:
	_subtitle_track = track
	_current_index = -1
	subtitle_hide.emit()

func _process(_delta: float) -> void:
	if not audio_player.playing or _subtitle_track.is_empty():
		return
	
	# Elite Pattern: Latency-Compensated Playback Position
	# get_playback_position() is chunked; adding time_since_last_mix and 
	# subtracting output_latency gives the true hardware-synced time.
	var time := audio_player.get_playback_position() + AudioServer.get_time_since_last_mix()
	time -= AudioServer.get_output_latency()
	
	_update_subtitles(time)

func _update_subtitles(current_time: float) -> void:
	var target_index = -1
	
	# Find the latest subtitle that should be visible
	for i in range(_subtitle_track.size()):
		if current_time >= _subtitle_track[i].time:
			target_index = i
		else:
			break
			
	if target_index != _current_index:
		_current_index = target_index
		if _current_index != -1:
			subtitle_show.emit(_subtitle_track[_current_index].text)
		else:
			subtitle_hide.emit()