kizzasi_model/

rwkv7.rs

//! RWKV v7: Next Generation Receptance Weighted Key Value (Forward-Compatible Scaffolding)
//!
//! This module provides scaffolding for RWKV v7, the next generation of the RWKV architecture.
//! As of this implementation, RWKV v7 has not been officially released, so this provides
//! a forward-compatible structure based on anticipated improvements.
//!
//! # Expected v7 Improvements
//!
//! - **Enhanced Time-Mixing**: Improved temporal dynamics
//! - **Better Gradient Flow**: Architectural improvements for deeper networks
//! - **Optimized Training**: More efficient parallel training algorithms
//! - **Extended Context**: Better long-range dependency modeling
//! - **Multi-Modal Support**: Native support for multi-modal inputs
//!
//! # Architecture (Anticipated)
//!
//! ```text
//! Input → [Enhanced Time-Mixing] → [Advanced Channel-Mixing] →
//!           ↓                              ↓
//!        [Optional Cross-Modal Fusion] → Output
//! ```
//!
//! # References
//!
//! - RWKV: https://github.com/BlinkDL/RWKV-LM
//! - Paper: https://arxiv.org/abs/2305.13048

use crate::error::{ModelError, ModelResult};
use crate::{AutoregressiveModel, ModelType};
use kizzasi_core::{CoreResult, HiddenState, LayerNorm, NormType, SignalPredictor};
use scirs2_core::ndarray::{Array1, Array2};
use scirs2_core::random::{rng, Rng};
use serde::{Deserialize, Serialize};

#[allow(unused_imports)]
use tracing::{debug, instrument, trace};

/// RWKV v7 configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Rwkv7Config {
    /// Input dimension
    pub input_dim: usize,
    /// Hidden dimension
    pub hidden_dim: usize,
    /// Number of layers
    pub num_layers: usize,
    /// Number of attention heads
    pub num_heads: usize,
    /// Head dimension
    pub head_dim: usize,
    /// Intermediate dimension
    pub intermediate_dim: usize,
    /// Time decay initialization
    pub time_decay_init: f32,
    /// Enhanced gradient flow (v7 feature)
    pub enhanced_gradient_flow: bool,
    /// Multi-modal support (v7 feature)
    pub multi_modal: bool,
    /// Extended context window (v7 feature)
    pub max_context_length: usize,
}

impl Default for Rwkv7Config {
    fn default() -> Self {
        let hidden_dim = 768;
        let num_heads = 12;
        Self {
            input_dim: 1,
            hidden_dim,
            num_layers: 24,
            num_heads,
            head_dim: hidden_dim / num_heads,
            intermediate_dim: hidden_dim * 4,
            time_decay_init: -6.0, // v7 may use different initialization
            enhanced_gradient_flow: true,
            multi_modal: false,
            max_context_length: 8192,
        }
    }
}

impl Rwkv7Config {
    /// Create a new RWKV v7 configuration
    pub fn new() -> Self {
        Self::default()
    }

    /// Small v7 model (similar to RWKV-v6 medium)
    pub fn small(input_dim: usize) -> Self {
        Self {
            input_dim,
            hidden_dim: 512,
            num_layers: 12,
            num_heads: 8,
            head_dim: 64,
            intermediate_dim: 2048,
            ..Default::default()
        }
    }

    /// Base v7 model (similar to RWKV-v6 large)
    pub fn base(input_dim: usize) -> Self {
        Self {
            input_dim,
            hidden_dim: 768,
            num_layers: 24,
            num_heads: 12,
            head_dim: 64,
            intermediate_dim: 3072,
            ..Default::default()
        }
    }

    /// Large v7 model (7B parameter scale)
    pub fn large(input_dim: usize) -> Self {
        Self {
            input_dim,
            hidden_dim: 4096,
            num_layers: 32,
            num_heads: 32,
            head_dim: 128,
            intermediate_dim: 16384,
            max_context_length: 16384,
            ..Default::default()
        }
    }

    /// Set input dimension
    pub fn input_dim(mut self, dim: usize) -> Self {
        self.input_dim = dim;
        self
    }

    /// Enable multi-modal support
    pub fn multi_modal(mut self, enable: bool) -> Self {
        self.multi_modal = enable;
        self
    }

    /// Set maximum context length
    pub fn max_context_length(mut self, length: usize) -> Self {
        self.max_context_length = length;
        self
    }

    /// Validate configuration
    pub fn validate(&self) -> ModelResult<()> {
        if self.hidden_dim == 0 {
            return Err(ModelError::invalid_config("hidden_dim must be > 0"));
        }
        if self.num_layers == 0 {
            return Err(ModelError::invalid_config("num_layers must be > 0"));
        }
        if self.num_heads == 0 {
            return Err(ModelError::invalid_config("num_heads must be > 0"));
        }
        if !self.hidden_dim.is_multiple_of(self.num_heads) {
            return Err(ModelError::invalid_config(
                "hidden_dim must be divisible by num_heads",
            ));
        }
        Ok(())
    }
}

/// Enhanced time-mixing block (v7 anticipated feature)
///
/// Note: This is scaffolding for future RWKV v7 implementation
#[allow(dead_code)]
struct EnhancedTimeMixing {
    hidden_dim: usize,
    num_heads: usize,
    head_dim: usize,

    // Time-mixing parameters
    time_decay: Array1<f32>,
    time_first: Array1<f32>,

    // Multi-head projections
    key_proj: Array2<f32>,
    value_proj: Array2<f32>,
    receptance_proj: Array2<f32>,
    gate_proj: Array2<f32>, // v7: additional gating
    output_proj: Array2<f32>,

    // Layer normalization
    ln: LayerNorm,

    // State per head
    state: Vec<Array1<f32>>,
}

impl EnhancedTimeMixing {
    #[allow(dead_code)]
    fn new(hidden_dim: usize, num_heads: usize) -> Self {
        let mut rng = rng();
        let head_dim = hidden_dim / num_heads;

        let scale = (1.0 / hidden_dim as f32).sqrt();

        // Initialize time decay (learnable)
        let time_decay = Array1::from_shape_fn(hidden_dim, |i| {
            let layer_idx = (i / head_dim) as f32;
            -6.0 - layer_idx * 0.1 // v7 may use different initialization
        });

        let time_first = Array1::from_shape_fn(hidden_dim, |_| (rng.random::<f32>() - 0.5) * 0.1);

        let key_proj = Array2::from_shape_fn((hidden_dim, hidden_dim), |_| {
            (rng.random::<f32>() - 0.5) * 2.0 * scale
        });

        let value_proj = Array2::from_shape_fn((hidden_dim, hidden_dim), |_| {
            (rng.random::<f32>() - 0.5) * 2.0 * scale
        });

        let receptance_proj = Array2::from_shape_fn((hidden_dim, hidden_dim), |_| {
            (rng.random::<f32>() - 0.5) * 2.0 * scale
        });

        let gate_proj = Array2::from_shape_fn((hidden_dim, hidden_dim), |_| {
            (rng.random::<f32>() - 0.5) * 2.0 * scale
        });

        let output_proj = Array2::from_shape_fn((hidden_dim, hidden_dim), |_| {
            (rng.random::<f32>() - 0.5) * 2.0 * scale
        });

        let ln = LayerNorm::new(hidden_dim, NormType::LayerNorm);

        let state = (0..num_heads)
            .map(|_| Array1::zeros(head_dim * 2))
            .collect();

        Self {
            hidden_dim,
            num_heads,
            head_dim,
            time_decay,
            time_first,
            key_proj,
            value_proj,
            receptance_proj,
            gate_proj,
            output_proj,
            ln,
            state,
        }
    }

    #[allow(dead_code)]
    fn forward(&mut self, x: &Array1<f32>) -> ModelResult<Array1<f32>> {
        // Placeholder for v7 enhanced time-mixing logic
        // This will be updated when RWKV v7 is officially released
        let normalized = self.ln.forward(x);
        Ok(normalized)
    }

    #[allow(dead_code)]
    fn reset(&mut self) {
        for state in &mut self.state {
            state.fill(0.0);
        }
    }
}

/// RWKV v7 model (scaffolding)
pub struct Rwkv7 {
    config: Rwkv7Config,
    // Layers will be added when v7 is released
    input_proj: Array2<f32>,
    output_proj: Array2<f32>,
}

impl Rwkv7 {
    /// Create a new RWKV v7 model
    pub fn new(config: Rwkv7Config) -> ModelResult<Self> {
        config.validate()?;

        let mut rng = rng();
        let scale = (1.0 / config.hidden_dim as f32).sqrt();

        let input_proj = Array2::from_shape_fn((config.hidden_dim, config.input_dim), |_| {
            (rng.random::<f32>() - 0.5) * 2.0 * scale
        });

        let output_proj = Array2::from_shape_fn((config.input_dim, config.hidden_dim), |_| {
            (rng.random::<f32>() - 0.5) * 2.0 * scale
        });

        debug!(
            "Created RWKV v7 model: {} layers, {} hidden_dim, {} heads (SCAFFOLDING)",
            config.num_layers, config.hidden_dim, config.num_heads
        );

        Ok(Self {
            config,
            input_proj,
            output_proj,
        })
    }

    /// Get configuration
    pub fn config(&self) -> &Rwkv7Config {
        &self.config
    }
}

impl SignalPredictor for Rwkv7 {
    fn step(&mut self, input: &Array1<f32>) -> CoreResult<Array1<f32>> {
        // Placeholder implementation
        // Full v7 implementation will be added when the architecture is released
        trace!("RWKV v7 forward pass (scaffolding)");

        // Simple pass-through for now
        let hidden = self.input_proj.dot(input);
        let output = self.output_proj.dot(&hidden);

        Ok(output)
    }

    fn reset(&mut self) {
        trace!("RWKV v7 reset state (scaffolding)");
        // State reset will be implemented when v7 is released
    }

    fn context_window(&self) -> usize {
        self.config.max_context_length
    }
}

impl AutoregressiveModel for Rwkv7 {
    fn hidden_dim(&self) -> usize {
        self.config.hidden_dim
    }

    fn state_dim(&self) -> usize {
        self.config.hidden_dim * self.config.num_layers
    }

    fn num_layers(&self) -> usize {
        self.config.num_layers
    }

    fn model_type(&self) -> ModelType {
        ModelType::Rwkv // Will be ModelType::Rwkv7 when added
    }

    fn get_states(&self) -> Vec<HiddenState> {
        // Placeholder: return empty states
        vec![]
    }

    fn set_states(&mut self, _states: Vec<HiddenState>) -> ModelResult<()> {
        // Placeholder: state management will be implemented with v7
        Ok(())
    }
}

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

    #[test]
    fn test_rwkv7_config_creation() {
        let config = Rwkv7Config::new();
        assert_eq!(config.num_heads, 12);
        assert_eq!(config.hidden_dim, 768);
    }

    #[test]
    fn test_rwkv7_small_config() {
        let config = Rwkv7Config::small(8);
        assert_eq!(config.input_dim, 8);
        assert_eq!(config.hidden_dim, 512);
        assert_eq!(config.num_layers, 12);
    }

    #[test]
    fn test_rwkv7_base_config() {
        let config = Rwkv7Config::base(8);
        assert_eq!(config.hidden_dim, 768);
        assert_eq!(config.num_layers, 24);
    }

    #[test]
    fn test_rwkv7_large_config() {
        let config = Rwkv7Config::large(8);
        assert_eq!(config.hidden_dim, 4096);
        assert_eq!(config.num_layers, 32);
        assert_eq!(config.max_context_length, 16384);
    }

    #[test]
    fn test_rwkv7_model_creation() {
        let config = Rwkv7Config::small(4);
        let model = Rwkv7::new(config);
        assert!(model.is_ok());
    }

    #[test]
    fn test_rwkv7_forward_pass() {
        let config = Rwkv7Config::small(4);
        let mut model = Rwkv7::new(config).expect("Failed to create RWKV7 model");

        let input = Array1::from_vec(vec![0.1, 0.2, 0.3, 0.4]);
        let output = model.step(&input);

        assert!(output.is_ok());
        assert_eq!(output.expect("Failed to get output").len(), 4);
    }

    #[test]
    fn test_rwkv7_multi_modal_config() {
        let config = Rwkv7Config::base(8).multi_modal(true);
        assert!(config.multi_modal);
    }

    #[test]
    fn test_rwkv7_validation() {
        let config = Rwkv7Config::new();
        assert!(config.validate().is_ok());

        let invalid_config = Rwkv7Config {
            hidden_dim: 0,
            ..Rwkv7Config::default()
        };
        assert!(invalid_config.validate().is_err());
    }
}