veza/veza-stream-server/src/audio_effects.rs

use serde::{Deserialize, Serialize};
use std::collections::HashMap;
// Note: Use tracing::info! macro directly instead of importing

/// Types d'effets audio supportés
#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
pub enum AudioEffectType {
    /// Equalizer avec bandes de fréquences configurables
    Equalizer {
        bands: Vec<EqBand>,
    },
    /// Normalisation du volume
    Normalization {
        target_level: f32, // dB
    },
    /// Réverbération
    Reverb {
        room_size: f32,
        damping: f32,
        wet_level: f32,
        dry_level: f32,
    },
    /// Écho/Delay
    Echo {
        delay_ms: u32,
        feedback: f32,
    },
    /// Compression
    Compression {
        threshold: f32,
        ratio: f32,
        attack: f32,
        release: f32,
    },
}

/// Bande de fréquence pour l'equalizer
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct EqBand {
    pub frequency: f32,  // Hz
    pub gain: f32,      // dB (-12 à +12)
    pub q_factor: f32,  // Bandwidth
}

/// Configuration d'effets audio pour un stream
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AudioEffectsConfig {
    pub user_id: i64,
    pub effects: Vec<AudioEffectType>,
}

/// Manager pour gérer les effets audio
pub struct AudioEffectsManager {
    /// Cache des configurations d'effets par user
    user_configs: HashMap<i64, AudioEffectsConfig>,
}

impl AudioEffectsManager {
    pub fn new() -> Self {
        Self {
            user_configs: HashMap::new(),
        }
    }

    /// Appliquer des effets audio à un buffer audio
    #[instrument(skip(self, audio_buffer))]
    pub fn apply_effects(
        &self,
        user_id: i64,
        audio_buffer: &mut Vec<f32>,
        effects: &[AudioEffectType],
    ) {
        for effect in effects {
            match effect {
                AudioEffectType::Equalizer { bands } => {
                    self.apply_equalizer(audio_buffer, bands);
                }
                AudioEffectType::Normalization { target_level } => {
                    self.apply_normalization(audio_buffer, *target_level);
                }
                AudioEffectType::Reverb { room_size, damping, wet_level, dry_level } => {
                    self.apply_reverb(audio_buffer, *room_size, *damping, *wet_level, *dry_level);
                }
                AudioEffectType::Echo { delay_ms, feedback } => {
                    self.apply_echo(audio_buffer, *delay_ms, *feedback);
                }
                AudioEffectType::Compression { threshold, ratio, attack, release } => {
                    self.apply_compression(audio_buffer, *threshold, *ratio, *attack, *release);
                }
            }
        }

        tracing::debug!(
            user_id = user_id,
            effects_count = effects.len(),
            "Effects applied to audio buffer"
        );
    }

    /// Appliquer un equalizer à un buffer audio
    fn apply_equalizer(&self, buffer: &mut Vec<f32>, bands: &[EqBand]) {
        // Note: Cette implémentation est simplifiée
        // Une implémentation réelle nécessiterait des FFT/FIR filters
        // Pour l'instant, on applique un gain simple par bande
        for band in bands {
            let gain_factor = 10.0_f32.powf(band.gain / 20.0);
            
            for sample in buffer.iter_mut() {
                // Application simplifiée du gain
                *sample *= gain_factor;
            }
        }

        tracing::info!("Equalizer applied with {} bands", bands.len());
    }

    /// Appliquer une normalisation du volume
    fn apply_normalization(&self, buffer: &mut Vec<f32>, target_level: f32) {
        // Trouver le pic le plus élevé
        let max_amplitude = buffer.iter().fold(0.0, |acc, &x| acc.max(x.abs()));
        
        if max_amplitude > 0.0 {
            let target_linear = 10.0_f32.powf(target_level / 20.0);
            let gain = target_linear / max_amplitude;
            
            for sample in buffer.iter_mut() {
                *sample *= gain;
            }
        }

        tracing::info!("Normalization applied to -{} dB", target_level);
    }

    /// Appliquer de la réverbération
    fn apply_reverb(
        &self,
        buffer: &mut Vec<f32>,
        room_size: f32,
        damping: f32,
        wet_level: f32,
        dry_level: f32,
    ) {
        // Note: Implémentation simplifiée de la réverbération
        // Une implémentation réelle utiliserait des all-pass filters et delays
        let reverb_buffer = buffer.clone();
        
        // Appliquer un delay avec feedback
        let delay_length = (0.03 * room_size * 44100.0) as usize; // Simplifié
        
        for i in delay_length..buffer.len() {
            let delayed = reverb_buffer[i - delay_length] * damping;
            buffer[i] = buffer[i] * dry_level + delayed * wet_level;
        }

        tracing::info!("Reverb applied with room_size={}", room_size);
    }

    /// Appliquer de l'écho
    fn apply_echo(&self, buffer: &mut Vec<f32>, delay_ms: u32, feedback: f32) {
        let delay_samples = (delay_ms as f32 * 44.1) as usize; // 44.1 kHz
        
        if delay_samples < buffer.len() {
            let original = buffer.clone();
            
            for i in delay_samples..buffer.len() {
                buffer[i] = original[i] + original[i - delay_samples] * feedback;
            }
        }

        tracing::info!("Echo applied with delay={} ms", delay_ms);
    }

    /// Appliquer de la compression
    fn apply_compression(
        &self,
        buffer: &mut Vec<f32>,
        threshold: f32,
        ratio: f32,
        attack: f32,
        release: f32,
    ) {
        // Note: Implémentation simplifiée de la compression
        // Une implémentation réelle utiliserait un envelope follower
        for sample in buffer.iter_mut() {
            let abs = sample.abs();
            
            if abs > threshold {
                let excess = abs - threshold;
                let compressed_excess = excess / ratio;
                let new_amplitude = threshold + compressed_excess;
                
                if *sample >= 0.0 {
                    *sample = new_amplitude;
                } else {
                    *sample = -new_amplitude;
                }
            }
        }

        tracing::info!("Compression applied with threshold={} dB", threshold);
    }

    /// Définir les effets audio pour un user
    #[instrument(skip(self))]
    pub fn set_user_effects(&mut self, user_id: i64, config: AudioEffectsConfig) {
        self.user_configs.insert(user_id, config);
        
        tracing::info!(user_id = user_id, "User audio effects configured");
    }

    /// Obtenir les effets audio d'un user
    pub fn get_user_effects(&self, user_id: i64) -> Option<&AudioEffectsConfig> {
        self.user_configs.get(&user_id)
    }

    /// Supprimer les effets audio d'un user
    #[instrument(skip(self))]
    pub fn clear_user_effects(&mut self, user_id: i64) {
        self.user_configs.remove(&user_id);
        
        tracing::info!(user_id = user_id, "User audio effects cleared");
    }
}

impl Default for AudioEffectsManager {
    fn default() -> Self {
        Self::new()
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_audio_effects_manager() {
        let mut manager = AudioEffectsManager::new();
        
        let mut buffer = vec![0.5, 0.3, 0.7, 0.2, 0.9];
        
        let effects = vec![
            AudioEffectType::Normalization {
                target_level: -3.0,
            },
        ];
        
        manager.apply_effects(1, &mut buffer, &effects);
        
        assert!(true);
    }
}