pinready 0.5.5

use crossbeam_channel::Sender;
use sdl3_sys::everything::*;
use std::ffi::CStr;
use std::thread;

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum Sound3DMode {
    FrontStereo = 0,
    RearStereo = 1,
    SurroundRearLockbar = 2,
    SurroundFrontLockbar = 3,
    SsfLegacy = 4,
    SsfNew = 5,
}

impl Sound3DMode {
    pub fn label(&self) -> &'static str {
        match self {
            Self::FrontStereo => "2ch -- Front stereo",
            Self::RearStereo => "2ch -- Rear stereo (lockbar)",
            Self::SurroundRearLockbar => "5.1 -- Rear at lockbar",
            Self::SurroundFrontLockbar => "5.1 -- Front at lockbar",
            Self::SsfLegacy => "SSF -- Side & Rear at lockbar (Legacy)",
            Self::SsfNew => "SSF -- Side & Rear at lockbar (New)",
        }
    }

    pub fn from_i32(v: i32) -> Self {
        match v {
            0 => Self::FrontStereo,
            1 => Self::RearStereo,
            2 => Self::SurroundRearLockbar,
            3 => Self::SurroundFrontLockbar,
            4 => Self::SsfLegacy,
            5 => Self::SsfNew,
            _ => Self::FrontStereo,
        }
    }

    pub fn all() -> &'static [Sound3DMode] {
        &[
            Self::FrontStereo,
            Self::RearStereo,
            Self::SurroundRearLockbar,
            Self::SurroundFrontLockbar,
            Self::SsfLegacy,
            Self::SsfNew,
        ]
    }
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum AudioTestPhase {
    Idle,
}

/// Which speaker(s) to play on in 7.1 layout
/// SDL3 7.1: FL(0), FR(1), FC(2), LFE(3), BL(4), BR(5), SL(6), SR(7)
/// In SSF pincab: BL/BR = top playfield (near backglass), SL/SR = bottom (lockbar)
#[derive(Clone, Copy)]
pub enum SpeakerTarget {
    /// Front L+R (backglass speakers)
    FrontBoth,
    /// BL only — top-left exciter (near backglass, left side)
    TopLeft,
    /// BR only — top-right exciter
    TopRight,
    /// SL only — bottom-left exciter (lockbar, left side)
    BottomLeft,
    /// SR only — bottom-right exciter (lockbar, right side)
    BottomRight,
    /// All top (BL+BR)
    TopBoth,
    /// All bottom (SL+SR)
    BottomBoth,
    /// All left (BL+SL)
    LeftBoth,
    /// All right (BR+SR)
    RightBoth,
}

pub enum AudioCommand {
    /// Play on specific speaker target
    PlayOnSpeaker {
        path: String,
        target: SpeakerTarget,
    },
    /// Play with hold at source, fade, hold at destination
    /// hold_start_ms: time on 'from' before fading
    /// fade_ms: crossfade duration
    /// hold_end_ms: time on 'to' after fading
    PlayBallSequence {
        path: String,
        from: SpeakerTarget,
        to: SpeakerTarget,
        hold_start_ms: u32,
        fade_ms: u32,
        hold_end_ms: u32,
    },
    /// Play music on front (backglass) with L/R pan
    StartMusic {
        path: String,
    },
    SetMusicPan {
        pan: f32,
    },
    StopMusic,
    #[allow(dead_code)]
    StopAll,
    #[allow(dead_code)]
    Quit,
}

#[derive(Debug, Clone)]
pub struct AudioConfig {
    pub available_devices: Vec<String>,
    pub device_bg: String,
    pub device_pf: String,
    pub sound_3d_mode: Sound3DMode,
    pub music_volume: i32,
    pub sound_volume: i32,
    #[allow(dead_code)]
    pub test_phase: AudioTestPhase,
    pub music_looping: bool,
    pub music_pan: f32,
}

impl Default for AudioConfig {
    fn default() -> Self {
        Self {
            available_devices: Vec::new(),
            device_bg: String::new(),
            device_pf: String::new(),
            sound_3d_mode: Sound3DMode::FrontStereo,
            music_volume: 100,
            sound_volume: 100,
            test_phase: AudioTestPhase::Idle,
            music_looping: false,
            music_pan: 0.0,
        }
    }
}

impl AudioConfig {
    pub fn load_from_config(&mut self, config: &crate::config::VpxConfig) {
        if let Some(v) = config.get("Player", "SoundDeviceBG") {
            self.device_bg = v;
        }
        if let Some(v) = config.get("Player", "SoundDevice") {
            self.device_pf = v;
        }
        if let Some(v) = config.get_i32("Player", "Sound3D") {
            self.sound_3d_mode = Sound3DMode::from_i32(v);
        }
        if let Some(v) = config.get_i32("Player", "MusicVolume") {
            self.music_volume = v;
        }
        if let Some(v) = config.get_i32("Player", "SoundVolume") {
            self.sound_volume = v;
        }
    }

    pub fn save_to_config(&self, config: &mut crate::config::VpxConfig) {
        config.set_sound_device_bg(&self.device_bg);
        config.set_sound_device_pf(&self.device_pf);
        config.set_sound_3d_mode(self.sound_3d_mode as i32);
        config.set_music_volume(self.music_volume);
        config.set_sound_volume(self.sound_volume);
    }

    pub fn enumerate_devices() -> Vec<String> {
        let mut devices = Vec::new();
        unsafe {
            let mut count: i32 = 0;
            let device_ids = SDL_GetAudioPlaybackDevices(&mut count);
            if !device_ids.is_null() {
                for i in 0..count as usize {
                    let id = *device_ids.add(i);
                    let name_ptr = SDL_GetAudioDeviceName(id);
                    if !name_ptr.is_null() {
                        devices.push(CStr::from_ptr(name_ptr).to_string_lossy().into_owned());
                    }
                }
                SDL_free(device_ids as *mut _);
            }
            log::info!("Found {} audio playback devices", count);
        }
        devices
    }
}

const SAMPLE_RATE: usize = 44100;

// Embedded audio assets
const KNOCKER_OGG: &[u8] = include_bytes!("../assets/audio/knocker.ogg");
const BALL_ROLL_OGG: &[u8] = include_bytes!("../assets/audio/ball_roll.ogg");
const MUSIC_OGG: &[u8] = include_bytes!("../assets/audio/music.ogg");

fn get_embedded_audio(name: &str) -> Option<&'static [u8]> {
    match name {
        "knocker.ogg" => Some(KNOCKER_OGG),
        "ball_roll.ogg" => Some(BALL_ROLL_OGG),
        "music.ogg" => Some(MUSIC_OGG),
        _ => None,
    }
}

/// Decode OGG to mono i16 PCM 44100Hz (single channel for multi-channel routing)
fn decode_to_mono_pcm(name: &str) -> Option<Vec<i16>> {
    use symphonia::core::audio::SampleBuffer;
    use symphonia::core::codecs::DecoderOptions;
    use symphonia::core::formats::FormatOptions;
    use symphonia::core::io::MediaSourceStream;
    use symphonia::core::meta::MetadataOptions;
    use symphonia::core::probe::Hint;

    let data = get_embedded_audio(name)?;
    let cursor = std::io::Cursor::new(data);
    let mss = MediaSourceStream::new(Box::new(cursor), Default::default());
    let mut hint = Hint::new();
    hint.with_extension("ogg");

    let probed = symphonia::default::get_probe()
        .format(
            &hint,
            mss,
            &FormatOptions::default(),
            &MetadataOptions::default(),
        )
        .ok()?;

    let mut format = probed.format;
    let track = format.default_track()?.clone();
    let mut decoder = symphonia::default::get_codecs()
        .make(&track.codec_params, &DecoderOptions::default())
        .ok()?;

    let mut samples: Vec<i16> = Vec::new();
    let channels = track.codec_params.channels.map(|c| c.count()).unwrap_or(1);

    while let Ok(packet) = format.next_packet() {
        if packet.track_id() != track.id {
            continue;
        }
        let decoded = match decoder.decode(&packet) {
            Ok(d) => d,
            Err(_) => continue,
        };
        let spec = *decoded.spec();
        let mut buf = SampleBuffer::<i16>::new(decoded.capacity() as u64, spec);
        buf.copy_interleaved_ref(decoded);
        let s = buf.samples();
        // Downmix to mono if stereo
        if channels >= 2 {
            for i in (0..s.len()).step_by(channels) {
                let mono = (s[i] as i32 + s[i + 1] as i32) / 2;
                samples.push(mono as i16);
            }
        } else {
            samples.extend_from_slice(s);
        }
    }

    log::info!(
        "Decoded {} (mono): {} samples ({:.1}s)",
        name,
        samples.len(),
        samples.len() as f32 / SAMPLE_RATE as f32
    );
    if samples.is_empty() {
        None
    } else {
        Some(samples)
    }
}

/// Decode to stereo i16 PCM (for music on front speakers)
fn decode_to_stereo_pcm(name: &str) -> Option<Vec<i16>> {
    use symphonia::core::audio::SampleBuffer;
    use symphonia::core::codecs::DecoderOptions;
    use symphonia::core::formats::FormatOptions;
    use symphonia::core::io::MediaSourceStream;
    use symphonia::core::meta::MetadataOptions;
    use symphonia::core::probe::Hint;

    let data = get_embedded_audio(name)?;
    let cursor = std::io::Cursor::new(data);
    let mss = MediaSourceStream::new(Box::new(cursor), Default::default());
    let mut hint = Hint::new();
    hint.with_extension("ogg");

    let probed = symphonia::default::get_probe()
        .format(
            &hint,
            mss,
            &FormatOptions::default(),
            &MetadataOptions::default(),
        )
        .ok()?;

    let mut format = probed.format;
    let track = format.default_track()?.clone();
    let mut decoder = symphonia::default::get_codecs()
        .make(&track.codec_params, &DecoderOptions::default())
        .ok()?;

    let mut samples: Vec<i16> = Vec::new();
    while let Ok(packet) = format.next_packet() {
        if packet.track_id() != track.id {
            continue;
        }
        let decoded = match decoder.decode(&packet) {
            Ok(d) => d,
            Err(_) => continue,
        };
        let spec = *decoded.spec();
        let mut buf = SampleBuffer::<i16>::new(decoded.capacity() as u64, spec);
        buf.copy_interleaved_ref(decoded);
        samples.extend_from_slice(buf.samples());
    }
    if samples.is_empty() {
        None
    } else {
        Some(samples)
    }
}

/// Route mono PCM to 8-channel (7.1) output on specific speakers
/// Returns 8-channel interleaved i16 data
pub(crate) fn mono_to_71(mono: &[i16], target: SpeakerTarget) -> Vec<i16> {
    // 7.1 layout: FL(0), FR(1), FC(2), LFE(3), BL(4), BR(5), SL(6), SR(7)
    // SSF pincab: BL/BR(4,5) = top playfield, SL/SR(6,7) = bottom/lockbar
    let mut out = vec![0i16; mono.len() * 8];
    for (i, &sample) in mono.iter().enumerate() {
        let base = i * 8;
        match target {
            SpeakerTarget::FrontBoth => {
                out[base] = sample;
                out[base + 1] = sample;
            }
            SpeakerTarget::TopLeft => {
                out[base + 4] = sample;
            }
            SpeakerTarget::TopRight => {
                out[base + 5] = sample;
            }
            SpeakerTarget::BottomLeft => {
                out[base + 6] = sample;
            }
            SpeakerTarget::BottomRight => {
                out[base + 7] = sample;
            }
            SpeakerTarget::TopBoth => {
                out[base + 4] = sample;
                out[base + 5] = sample;
            }
            SpeakerTarget::BottomBoth => {
                out[base + 6] = sample;
                out[base + 7] = sample;
            }
            SpeakerTarget::LeftBoth => {
                out[base + 4] = sample;
                out[base + 6] = sample;
            }
            SpeakerTarget::RightBoth => {
                out[base + 5] = sample;
                out[base + 7] = sample;
            }
        }
    }
    out
}

/// Route stereo PCM to 8-channel with L/R pan on front speakers (for music)
pub(crate) fn stereo_to_71_front(stereo: &[i16], pan: f32) -> Vec<i16> {
    let lg = (1.0 - pan.max(0.0)).min(1.0);
    let rg = (1.0 + pan.min(0.0)).min(1.0);
    let stereo_frames = stereo.len() / 2;
    let mut out = vec![0i16; stereo_frames * 8];
    for i in 0..stereo_frames {
        let base = i * 8;
        let l = stereo[i * 2];
        let r = stereo[i * 2 + 1];
        out[base] = (l as f32 * lg) as i16; // FL
        out[base + 1] = (r as f32 * rg) as i16; // FR
    }
    out
}

/// Spawn audio thread with 8-channel (7.1) output
pub fn spawn_audio_thread() -> Sender<AudioCommand> {
    let (cmd_tx, cmd_rx) = crossbeam_channel::unbounded::<AudioCommand>();

    thread::spawn(move || {
        unsafe {
            if !SDL_InitSubSystem(SDL_INIT_AUDIO) {
                log::error!(
                    "Audio: SDL_InitSubSystem failed: {:?}",
                    CStr::from_ptr(SDL_GetError())
                );
                return;
            }

            // 8 channels (7.1) for SSF speaker routing, i16, 44100Hz
            let spec = SDL_AudioSpec {
                format: SDL_AUDIO_S16,
                channels: 8,
                freq: 44100,
            };

            let stream = SDL_OpenAudioDeviceStream(
                SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK,
                &spec,
                None,
                std::ptr::null_mut(),
            );
            if stream.is_null() {
                log::error!(
                    "Audio: OpenAudioDeviceStream 7.1 failed: {:?}",
                    CStr::from_ptr(SDL_GetError())
                );
                SDL_QuitSubSystem(SDL_INIT_AUDIO);
                return;
            }
            SDL_ResumeAudioStreamDevice(stream);
            log::info!("Audio thread: 7.1 stream opened and resumed");

            let mut music_pcm: Option<Vec<i16>> = None; // stereo cache

            loop {
                match cmd_rx.recv() {
                    Ok(AudioCommand::PlayOnSpeaker { path, target }) => {
                        log::info!("Audio: PlayOnSpeaker {}", path);
                        if let Some(mono) = decode_to_mono_pcm(&path) {
                            let data = mono_to_71(&mono, target);
                            SDL_ClearAudioStream(stream);
                            SDL_PutAudioStreamData(
                                stream,
                                data.as_ptr() as *const _,
                                (data.len() * 2) as i32,
                            );
                            SDL_FlushAudioStream(stream);
                        }
                    }
                    Ok(AudioCommand::PlayBallSequence {
                        path,
                        from,
                        to,
                        hold_start_ms,
                        fade_ms,
                        hold_end_ms,
                    }) => {
                        log::info!(
                            "Audio: PlayBallSequence {} hold_start={}ms fade={}ms hold_end={}ms",
                            path,
                            hold_start_ms,
                            fade_ms,
                            hold_end_ms
                        );
                        if let Some(mono) = decode_to_mono_pcm(&path) {
                            SDL_ClearAudioStream(stream);

                            let samples_per_ms = SAMPLE_RATE / 1000;
                            let hold_start_samples = hold_start_ms as usize * samples_per_ms;
                            let fade_samples = fade_ms as usize * samples_per_ms;
                            let hold_end_samples = hold_end_ms as usize * samples_per_ms;

                            let mut offset = 0;

                            // Phase 1: hold on 'from'
                            let end1 = (offset + hold_start_samples).min(mono.len());
                            if offset < end1 {
                                let data = mono_to_71(&mono[offset..end1], from);
                                SDL_PutAudioStreamData(
                                    stream,
                                    data.as_ptr() as *const _,
                                    (data.len() * 2) as i32,
                                );
                                offset = end1;
                            }

                            // Phase 2: crossfade from -> to
                            let chunk_ms = 50u32;
                            let chunk_samples = chunk_ms as usize * samples_per_ms;
                            let fade_end = (offset + fade_samples).min(mono.len());
                            let fade_total = fade_end - offset;
                            let mut fade_pos = 0;
                            while offset < fade_end {
                                let end = (offset + chunk_samples).min(fade_end);
                                let chunk = &mono[offset..end];
                                let t = if fade_total > 0 {
                                    fade_pos as f32 / fade_total as f32
                                } else {
                                    1.0
                                };

                                let from_data = mono_to_71(chunk, from);
                                let to_data = mono_to_71(chunk, to);
                                let mixed: Vec<i16> = from_data
                                    .iter()
                                    .zip(to_data.iter())
                                    .map(|(&a, &b)| {
                                        ((a as f32 * (1.0 - t)) + (b as f32 * t)) as i16
                                    })
                                    .collect();
                                SDL_PutAudioStreamData(
                                    stream,
                                    mixed.as_ptr() as *const _,
                                    (mixed.len() * 2) as i32,
                                );

                                fade_pos += end - offset;
                                offset = end;
                            }

                            // Phase 3: hold on 'to'
                            let end3 = (offset + hold_end_samples).min(mono.len());
                            if offset < end3 {
                                let data = mono_to_71(&mono[offset..end3], to);
                                SDL_PutAudioStreamData(
                                    stream,
                                    data.as_ptr() as *const _,
                                    (data.len() * 2) as i32,
                                );
                            }

                            SDL_FlushAudioStream(stream);
                            let total_ms = hold_start_ms + fade_ms + hold_end_ms;
                            std::thread::sleep(std::time::Duration::from_millis(total_ms as u64));
                        }
                    }
                    Ok(AudioCommand::StartMusic { path }) => {
                        log::info!("Audio: StartMusic {}", path);
                        if let Some(stereo) = decode_to_stereo_pcm(&path) {
                            let data = stereo_to_71_front(&stereo, 0.0);
                            music_pcm = Some(stereo);
                            SDL_ClearAudioStream(stream);
                            SDL_PutAudioStreamData(
                                stream,
                                data.as_ptr() as *const _,
                                (data.len() * 2) as i32,
                            );
                            SDL_FlushAudioStream(stream);
                        }
                    }
                    Ok(AudioCommand::SetMusicPan { pan }) => {
                        // Store pan and restart music cleanly
                        if let Some(ref stereo) = music_pcm {
                            let data = stereo_to_71_front(stereo, pan);
                            SDL_ClearAudioStream(stream);
                            SDL_PutAudioStreamData(
                                stream,
                                data.as_ptr() as *const _,
                                (data.len() * 2) as i32,
                            );
                            SDL_FlushAudioStream(stream);
                        }
                    }
                    Ok(AudioCommand::StopMusic) | Ok(AudioCommand::StopAll) => {
                        SDL_ClearAudioStream(stream);
                        music_pcm = None;
                    }
                    Ok(AudioCommand::Quit) | Err(_) => break,
                }
            }
            SDL_DestroyAudioStream(stream);
            SDL_QuitSubSystem(SDL_INIT_AUDIO);
        }
    });

    cmd_tx
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::config::VpxConfig;
    use std::io::Write;
    use tempfile::NamedTempFile;

    fn config_from_str(content: &str) -> VpxConfig {
        let mut tmp = NamedTempFile::new().unwrap();
        tmp.write_all(content.as_bytes()).unwrap();
        VpxConfig::load(Some(tmp.path())).unwrap()
    }

    // --- Sound3DMode ---

    #[test]
    fn sound_3d_mode_from_i32_valid() {
        assert_eq!(Sound3DMode::from_i32(0), Sound3DMode::FrontStereo);
        assert_eq!(Sound3DMode::from_i32(1), Sound3DMode::RearStereo);
        assert_eq!(Sound3DMode::from_i32(2), Sound3DMode::SurroundRearLockbar);
        assert_eq!(Sound3DMode::from_i32(3), Sound3DMode::SurroundFrontLockbar);
        assert_eq!(Sound3DMode::from_i32(4), Sound3DMode::SsfLegacy);
        assert_eq!(Sound3DMode::from_i32(5), Sound3DMode::SsfNew);
    }

    #[test]
    fn sound_3d_mode_from_i32_invalid_defaults() {
        assert_eq!(Sound3DMode::from_i32(-1), Sound3DMode::FrontStereo);
        assert_eq!(Sound3DMode::from_i32(6), Sound3DMode::FrontStereo);
        assert_eq!(Sound3DMode::from_i32(999), Sound3DMode::FrontStereo);
    }

    #[test]
    fn sound_3d_mode_all_has_6_entries() {
        assert_eq!(Sound3DMode::all().len(), 6);
    }

    #[test]
    fn sound_3d_mode_roundtrip_i32() {
        for mode in Sound3DMode::all() {
            assert_eq!(Sound3DMode::from_i32(*mode as i32), *mode);
        }
    }

    #[test]
    fn sound_3d_mode_labels_not_empty() {
        for mode in Sound3DMode::all() {
            assert!(!mode.label().is_empty());
        }
    }

    // --- AudioConfig default ---

    #[test]
    fn audio_config_default() {
        let cfg = AudioConfig::default();
        assert!(cfg.available_devices.is_empty());
        assert!(cfg.device_bg.is_empty());
        assert!(cfg.device_pf.is_empty());
        assert_eq!(cfg.sound_3d_mode, Sound3DMode::FrontStereo);
        assert_eq!(cfg.music_volume, 100);
        assert_eq!(cfg.sound_volume, 100);
        assert!(!cfg.music_looping);
        assert!((cfg.music_pan - 0.0).abs() < f32::EPSILON);
    }

    // --- AudioConfig load/save ---

    #[test]
    fn audio_config_load_from_config() {
        let cfg = config_from_str(
            "[Player]\nSoundDeviceBG = HD Audio\nSoundDevice = USB\n\
             Sound3D = 4\nMusicVolume = 75\nSoundVolume = 50\n",
        );
        let mut audio = AudioConfig::default();
        audio.load_from_config(&cfg);
        assert_eq!(audio.device_bg, "HD Audio");
        assert_eq!(audio.device_pf, "USB");
        assert_eq!(audio.sound_3d_mode, Sound3DMode::SsfLegacy);
        assert_eq!(audio.music_volume, 75);
        assert_eq!(audio.sound_volume, 50);
    }

    #[test]
    fn audio_config_load_empty_keeps_defaults() {
        let cfg = config_from_str("");
        let mut audio = AudioConfig::default();
        audio.load_from_config(&cfg);
        assert_eq!(audio.music_volume, 100);
        assert_eq!(audio.sound_3d_mode, Sound3DMode::FrontStereo);
    }

    #[test]
    fn audio_config_save_to_config() {
        let mut cfg = config_from_str("");
        let audio = AudioConfig {
            device_bg: "Speaker A".to_string(),
            device_pf: "Speaker B".to_string(),
            sound_3d_mode: Sound3DMode::SsfNew,
            music_volume: 80,
            sound_volume: 60,
            ..Default::default()
        };
        audio.save_to_config(&mut cfg);
        assert_eq!(
            cfg.get("Player", "SoundDeviceBG"),
            Some("Speaker A".to_string())
        );
        assert_eq!(
            cfg.get("Player", "SoundDevice"),
            Some("Speaker B".to_string())
        );
        assert_eq!(cfg.get_i32("Player", "Sound3D"), Some(5));
        assert_eq!(cfg.get_i32("Player", "MusicVolume"), Some(80));
        assert_eq!(cfg.get_i32("Player", "SoundVolume"), Some(60));
    }

    // --- mono_to_71 ---

    #[test]
    fn mono_to_71_front_both() {
        let mono = vec![1000i16, 2000];
        let out = mono_to_71(&mono, SpeakerTarget::FrontBoth);
        assert_eq!(out.len(), 16); // 2 samples × 8 channels
                                   // Frame 0: FL=1000, FR=1000, rest=0
        assert_eq!(out[0], 1000);
        assert_eq!(out[1], 1000);
        assert_eq!(out[2], 0);
        // Frame 1: FL=2000, FR=2000
        assert_eq!(out[8], 2000);
        assert_eq!(out[9], 2000);
    }

    #[test]
    fn mono_to_71_top_left() {
        let mono = vec![500i16];
        let out = mono_to_71(&mono, SpeakerTarget::TopLeft);
        // BL is channel 4
        assert_eq!(out[4], 500);
        assert_eq!(out[0], 0); // FL silent
        assert_eq!(out[5], 0); // BR silent
    }

    #[test]
    fn mono_to_71_bottom_both() {
        let mono = vec![300i16];
        let out = mono_to_71(&mono, SpeakerTarget::BottomBoth);
        // SL(6) and SR(7)
        assert_eq!(out[6], 300);
        assert_eq!(out[7], 300);
        assert_eq!(out[4], 0); // BL silent
    }

    #[test]
    fn mono_to_71_left_both() {
        let mono = vec![400i16];
        let out = mono_to_71(&mono, SpeakerTarget::LeftBoth);
        // BL(4) and SL(6)
        assert_eq!(out[4], 400);
        assert_eq!(out[6], 400);
        assert_eq!(out[5], 0); // BR silent
        assert_eq!(out[7], 0); // SR silent
    }

    #[test]
    fn mono_to_71_empty_input() {
        let out = mono_to_71(&[], SpeakerTarget::FrontBoth);
        assert!(out.is_empty());
    }

    // --- stereo_to_71_front ---

    #[test]
    fn stereo_to_71_center_pan() {
        let stereo = vec![1000i16, 2000]; // L=1000, R=2000
        let out = stereo_to_71_front(&stereo, 0.0);
        assert_eq!(out.len(), 8); // 1 frame × 8 channels
        assert_eq!(out[0], 1000); // FL
        assert_eq!(out[1], 2000); // FR
        assert_eq!(out[2], 0); // FC
    }

    #[test]
    fn stereo_to_71_full_left_pan() {
        let stereo = vec![1000i16, 1000];
        let out = stereo_to_71_front(&stereo, -1.0);
        assert_eq!(out[0], 1000); // FL at full
        assert_eq!(out[1], 0); // FR muted
    }

    #[test]
    fn stereo_to_71_full_right_pan() {
        let stereo = vec![1000i16, 1000];
        let out = stereo_to_71_front(&stereo, 1.0);
        assert_eq!(out[0], 0); // FL muted
        assert_eq!(out[1], 1000); // FR at full
    }

    #[test]
    fn stereo_to_71_empty() {
        let out = stereo_to_71_front(&[], 0.0);
        assert!(out.is_empty());
    }

    // --- Embedded audio ---

    #[test]
    fn embedded_audio_knocker_exists() {
        assert!(get_embedded_audio("knocker.ogg").is_some());
    }

    #[test]
    fn embedded_audio_ball_roll_exists() {
        assert!(get_embedded_audio("ball_roll.ogg").is_some());
    }

    #[test]
    fn embedded_audio_music_exists() {
        assert!(get_embedded_audio("music.ogg").is_some());
    }

    #[test]
    fn embedded_audio_unknown_returns_none() {
        assert!(get_embedded_audio("nonexistent.ogg").is_none());
    }

    // --- Audio decoding ---

    #[test]
    fn decode_knocker_to_mono() {
        let pcm = decode_to_mono_pcm("knocker.ogg");
        assert!(pcm.is_some(), "knocker.ogg should decode to mono PCM");
        let samples = pcm.unwrap();
        assert!(!samples.is_empty());
    }

    #[test]
    fn decode_music_to_stereo() {
        let pcm = decode_to_stereo_pcm("music.ogg");
        assert!(pcm.is_some(), "music.ogg should decode to stereo PCM");
        let samples = pcm.unwrap();
        assert!(!samples.is_empty());
        // Stereo = even number of samples
        assert_eq!(samples.len() % 2, 0);
    }

    #[test]
    fn decode_nonexistent_returns_none() {
        assert!(decode_to_mono_pcm("does_not_exist.ogg").is_none());
    }
}