voirs_conversion/style_transfer/

components.rs

//! Component structures for style transfer

use crate::Result;
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use std::sync::{Arc, RwLock};
use std::time::{Duration, Instant};

use super::config::*;
use super::traits::*;

/// Content representation
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ContentRepresentation {
    /// Content features
    pub features: Vec<f32>,

    /// Temporal alignment
    pub temporal_alignment: Vec<f32>,

    /// Confidence score
    pub confidence: f32,
}

/// Style representation
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StyleRepresentation {
    /// Style features
    pub features: Vec<f32>,

    /// Style embedding
    pub embedding: Vec<f32>,

    /// Style confidence
    pub confidence: f32,
}

/// Decomposition configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DecompositionConfig {
    /// Content weight
    pub content_weight: f32,

    /// Style weight
    pub style_weight: f32,

    /// Orthogonality constraint
    pub orthogonality_constraint: f32,

    /// Reconstruction weight
    pub reconstruction_weight: f32,
}

/// Decomposition result
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DecompositionResult {
    /// Content representation
    pub content: ContentRepresentation,

    /// Style representation
    pub style: StyleRepresentation,

    /// Decomposition quality
    pub quality: f32,

    /// Processing time
    pub processing_time: Duration,
}

/// Style encoder configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StyleEncoderConfig {
    /// Enabled extractors
    pub enabled_extractors: Vec<String>,

    /// Feature dimensions per extractor
    pub feature_dims: HashMap<String, usize>,

    /// Embedding dimension
    pub embedding_dim: usize,

    /// Normalization enabled
    pub normalization: bool,

    /// Feature fusion method
    pub fusion_method: FeatureFusionMethod,
}

/// Feature fusion method
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum FeatureFusionMethod {
    /// Concatenation
    Concatenation,

    /// Weighted average
    WeightedAverage,

    /// Attention-based fusion
    Attention,
}

/// Style encoder (main component)
pub struct StyleEncoder {
    /// Style extraction models
    extractors: HashMap<String, Box<dyn StyleExtractorTrait>>,

    /// Style embedding network
    embedding_network: Box<dyn EmbeddingNetwork>,

    /// Encoder configuration
    config: StyleEncoderConfig,
}

/// Style decoder configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StyleDecoderConfig {
    /// Synthesis method
    pub synthesis_method: SynthesisMethod,

    /// Decoder types
    pub decoder_types: Vec<String>,

    /// Decoder parameters
    pub decoder_params: HashMap<String, f32>,

    /// Quality enhancement enabled
    pub quality_enhancement: bool,

    /// Post processing enabled
    pub post_processing: bool,
}

/// Style decoder (main component)
pub struct StyleDecoder {
    /// Style decoders by method
    decoders: HashMap<String, Box<dyn StyleDecoderTrait>>,

    /// Synthesis network
    synthesis_network: Box<dyn SynthesisNetwork>,

    /// Decoder configuration
    config: StyleDecoderConfig,
}

/// Style quality assessor
pub struct StyleQualityAssessor {
    /// Quality metrics
    metrics: HashMap<String, Box<dyn StyleQualityMetric>>,

    /// Assessor configuration
    config: StyleQualityConfig,

    /// Assessment history
    history: Arc<RwLock<Vec<StyleQualityAssessment>>>,
}

/// Content-style decomposer
pub struct ContentStyleDecomposer {
    /// Content encoder
    content_encoder: Box<dyn ContentEncoder>,

    /// Style encoder
    style_encoder: Box<dyn StyleEncoderTrait>,

    /// Decomposition configuration
    config: DecompositionConfig,

    /// Decomposition cache
    cache: Arc<RwLock<HashMap<String, DecompositionResult>>>,
}

/// Content encoder trait
/// Style quality configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StyleQualityConfig {
    /// Enabled metrics
    pub enabled_metrics: Vec<String>,

    /// Quality thresholds
    pub thresholds: HashMap<String, f32>,

    /// Weighting scheme
    pub weights: HashMap<String, f32>,

    /// Assessment frequency
    pub assessment_frequency: StyleAssessmentFrequency,
}

/// Style assessment frequency
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum StyleAssessmentFrequency {
    /// Every transfer
    Every,

    /// Periodic assessment
    Periodic,

    /// Threshold-based
    ThresholdBased,

    /// On-demand
    OnDemand,
}

/// Style quality assessment
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StyleQualityAssessment {
    /// Overall quality score
    pub overall_score: f32,

    /// Individual metric scores
    pub metric_scores: HashMap<String, f32>,

    /// Style transfer accuracy
    pub transfer_accuracy: f32,

    /// Content preservation score
    pub content_preservation: f32,

    /// Assessment timestamp
    #[serde(skip)]
    pub timestamp: Option<Instant>,

    /// Assessment confidence
    pub confidence: f32,
}

/// Style transfer metrics
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StyleTransferMetrics {
    /// Number of successful transfers
    pub successful_transfers: u64,

    /// Number of failed transfers
    pub failed_transfers: u64,

    /// Average processing time (ms)
    pub avg_processing_time: f32,

    /// Average quality score
    pub avg_quality_score: f32,

    /// Cache hit rate
    pub cache_hit_rate: f32,

    /// Style model utilization
    pub model_utilization: HashMap<String, f32>,

    /// Performance statistics
    pub performance_stats: StylePerformanceStats,
}

/// Style performance statistics
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StylePerformanceStats {
    /// CPU usage (%)
    pub cpu_usage: f32,

    /// Memory usage (MB)
    pub memory_usage: f32,

    /// GPU usage (%)
    pub gpu_usage: Option<f32>,

    /// I/O throughput (MB/s)
    pub io_throughput: f32,

    /// Network usage (MB/s)
    pub network_usage: f32,
}

/// Cached style transfer
#[derive(Debug, Clone)]
pub struct CachedStyleTransfer {
    /// Transfer result
    pub result: Vec<f32>,

    /// Transfer quality
    pub quality: f32,

    /// Processing time
    pub processing_time: Duration,

    /// Cache timestamp
    pub timestamp: Instant,

    /// Usage count
    pub usage_count: u32,

    /// Transfer metadata
    pub metadata: TransferMetadata,
}

/// Transfer metadata
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TransferMetadata {
    /// Source style ID
    pub source_style_id: String,

    /// Target style ID
    pub target_style_id: String,

    /// Transfer method used
    pub method: StyleTransferMethod,

    /// Configuration hash
    pub config_hash: String,
}

// Main implementation

// Implementations

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

impl ContentStyleDecomposer {
    /// Creates a new content-style decomposer with default configuration.
    ///
    /// # Returns
    ///
    /// A new `ContentStyleDecomposer` instance with dummy encoders and default weights.
    pub fn new() -> Self {
        Self {
            content_encoder: Box::new(DummyContentEncoder),
            style_encoder: Box::new(DummyStyleEncoder),
            config: DecompositionConfig {
                content_weight: 1.0,
                style_weight: 1.0,
                orthogonality_constraint: 0.1,
                reconstruction_weight: 1.0,
            },
            cache: Arc::new(RwLock::new(HashMap::new())),
        }
    }

    /// Decomposes audio into separate content and style representations.
    ///
    /// # Arguments
    ///
    /// * `audio` - The input audio samples
    /// * `sample_rate` - The sample rate of the audio in Hz
    ///
    /// # Returns
    ///
    /// A `DecompositionResult` containing content and style representations with quality metrics.
    ///
    /// # Errors
    ///
    /// Returns an error if encoding fails for either content or style.
    pub fn decompose(&self, audio: &[f32], sample_rate: u32) -> Result<DecompositionResult> {
        let start_time = Instant::now();

        let content = self.content_encoder.encode_content(audio, sample_rate)?;
        let style = self.style_encoder.encode_style(audio, sample_rate)?;

        Ok(DecompositionResult {
            content,
            style,
            quality: 0.8,
            processing_time: start_time.elapsed(),
        })
    }
}

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

impl StyleEncoder {
    /// Creates a new style encoder with default configuration.
    ///
    /// # Returns
    ///
    /// A new `StyleEncoder` instance with empty extractors and 256-dimensional embeddings.
    pub fn new() -> Self {
        Self {
            extractors: HashMap::new(),
            embedding_network: Box::new(DummyEmbeddingNetwork),
            config: StyleEncoderConfig {
                enabled_extractors: Vec::new(),
                feature_dims: HashMap::new(),
                embedding_dim: 256,
                normalization: true,
                fusion_method: FeatureFusionMethod::Concatenation,
            },
        }
    }

    /// Encodes the style characteristics of audio into a compact representation.
    ///
    /// # Arguments
    ///
    /// * `audio` - The input audio samples
    /// * `sample_rate` - The sample rate of the audio in Hz
    ///
    /// # Returns
    ///
    /// A `StyleRepresentation` containing extracted features, embeddings, and confidence score.
    ///
    /// # Errors
    ///
    /// Returns an error if feature extraction or embedding computation fails.
    pub fn encode_style(&self, audio: &[f32], sample_rate: u32) -> Result<StyleRepresentation> {
        // Extract features from all extractors
        let mut all_features = Vec::new();
        for extractor in self.extractors.values() {
            let features = extractor.extract_features(audio, sample_rate)?;
            all_features.extend(features);
        }

        // Compute embedding
        let embedding = self.embedding_network.compute_embedding(&all_features)?;

        Ok(StyleRepresentation {
            features: all_features,
            embedding,
            confidence: 0.8,
        })
    }
}

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

impl StyleDecoder {
    /// Creates a new style decoder with default configuration.
    ///
    /// # Returns
    ///
    /// A new `StyleDecoder` instance with neural vocoder synthesis enabled.
    pub fn new() -> Self {
        Self {
            decoders: HashMap::new(),
            synthesis_network: Box::new(DummySynthesisNetwork),
            config: StyleDecoderConfig {
                synthesis_method: SynthesisMethod::NeuralVocoder,
                decoder_types: vec!["neural".to_string()],
                decoder_params: HashMap::new(),
                quality_enhancement: true,
                post_processing: true,
            },
        }
    }

    /// Decodes content and style representations and synthesizes output audio.
    ///
    /// # Arguments
    ///
    /// * `content` - The content representation to preserve
    /// * `style` - The style representation to apply
    /// * `sample_rate` - The desired output sample rate in Hz
    ///
    /// # Returns
    ///
    /// A vector of synthesized audio samples.
    ///
    /// # Errors
    ///
    /// Returns an error if synthesis fails.
    pub fn decode_and_synthesize(
        &self,
        content: &ContentRepresentation,
        style: &StyleRepresentation,
        sample_rate: u32,
    ) -> Result<Vec<f32>> {
        self.synthesis_network
            .synthesize(content, style, sample_rate)
    }
}

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

impl StyleQualityAssessor {
    /// Creates a new style quality assessor with default metrics.
    ///
    /// # Returns
    ///
    /// A new `StyleQualityAssessor` instance configured to assess style similarity and content preservation.
    pub fn new() -> Self {
        Self {
            metrics: HashMap::new(),
            config: StyleQualityConfig {
                enabled_metrics: vec![
                    "style_similarity".to_string(),
                    "content_preservation".to_string(),
                ],
                thresholds: HashMap::new(),
                weights: HashMap::new(),
                assessment_frequency: StyleAssessmentFrequency::Every,
            },
            history: Arc::new(RwLock::new(Vec::new())),
        }
    }

    /// Assesses the quality of a style transfer operation.
    ///
    /// # Arguments
    ///
    /// * `original` - The original audio samples
    /// * `transferred` - The style-transferred audio samples
    /// * `target_style` - The target style representation that was applied
    /// * `sample_rate` - The sample rate of the audio in Hz
    ///
    /// # Returns
    ///
    /// A quality score between 0.0 and 1.0, where higher values indicate better transfer quality.
    ///
    /// # Errors
    ///
    /// Returns an error if quality assessment fails.
    pub fn assess_transfer_quality(
        &self,
        original: &[f32],
        transferred: &[f32],
        target_style: &StyleRepresentation,
        sample_rate: u32,
    ) -> Result<f32> {
        // Simplified quality assessment
        let mut total_score = 0.0;
        let mut weight_sum = 0.0;

        for metric_name in &self.config.enabled_metrics {
            if let Some(metric) = self.metrics.get(metric_name) {
                let score = metric.assess(original, transferred, target_style, sample_rate)?;
                let weight = self.config.weights.get(metric_name).unwrap_or(&1.0);
                total_score += score * weight;
                weight_sum += weight;
            }
        }

        if weight_sum > 0.0 {
            Ok(total_score / weight_sum)
        } else {
            Ok(0.5) // Default score
        }
    }
}

impl Default for StyleTransferMetrics {
    fn default() -> Self {
        Self {
            successful_transfers: 0,
            failed_transfers: 0,
            avg_processing_time: 0.0,
            avg_quality_score: 0.0,
            cache_hit_rate: 0.0,
            model_utilization: HashMap::new(),
            performance_stats: StylePerformanceStats {
                cpu_usage: 0.0,
                memory_usage: 0.0,
                gpu_usage: None,
                io_throughput: 0.0,
                network_usage: 0.0,
            },
        }
    }
}

// Dummy implementations for traits

struct DummyContentEncoder;
impl ContentEncoder for DummyContentEncoder {
    fn encode_content(&self, audio: &[f32], sample_rate: u32) -> Result<ContentRepresentation> {
        Ok(ContentRepresentation {
            features: vec![0.0; 256],
            temporal_alignment: vec![0.0; audio.len() / 1000],
            confidence: 0.8,
        })
    }

    fn content_dim(&self) -> usize {
        256
    }
}

struct DummyStyleEncoder;
impl StyleEncoderTrait for DummyStyleEncoder {
    fn encode_style(&self, audio: &[f32], sample_rate: u32) -> Result<StyleRepresentation> {
        Ok(StyleRepresentation {
            features: vec![0.0; 128],
            embedding: vec![0.0; 64],
            confidence: 0.8,
        })
    }

    fn style_dim(&self) -> usize {
        128
    }
}

struct DummyEmbeddingNetwork;
impl EmbeddingNetwork for DummyEmbeddingNetwork {
    fn compute_embedding(&self, features: &[f32]) -> Result<Vec<f32>> {
        Ok(vec![0.0; 256])
    }

    fn embedding_dim(&self) -> usize {
        256
    }
}

struct DummySynthesisNetwork;
impl SynthesisNetwork for DummySynthesisNetwork {
    fn synthesize(
        &self,
        content: &ContentRepresentation,
        style: &StyleRepresentation,
        sample_rate: u32,
    ) -> Result<Vec<f32>> {
        // Simplified synthesis - return dummy audio
        Ok(vec![0.0; sample_rate as usize]) // 1 second of silence
    }

    fn method(&self) -> SynthesisMethod {
        SynthesisMethod::NeuralVocoder
    }
}