scribe-analysis 0.5.1

//! # Heuristic Scoring System for File Prioritization
//!
//! Implements a sophisticated multi-dimensional scoring system for ranking file importance
//! within a codebase. This module ports and enhances the legacy Python heuristics that
//! originally powered Scribe, while adding more robust Rust-based features:
//!
//! ## Core Scoring Formula
//! ```text
//! score = w_doc*doc + w_readme*readme + w_imp*imp_deg + w_path*path_depth^-1 +
//!         w_test*test_link + w_churn*churn + w_centrality*centrality +
//!         w_entrypoint*entrypoint + w_examples*examples + priority_boost
//! ```
//!
//! ## Key Features
//! - **Template Detection**: Advanced template engine detection using multiple methods
//! - **Import Graph Analysis**: Dependency centrality and PageRank calculations
//! - **Documentation Intelligence**: README prioritization and document structure analysis
//! - **Test-Code Relationships**: Heuristic test file linkage detection
//! - **Git Churn Integration**: Change recency and frequency signals
//! - **Configurable Weighting**: V1/V2 feature flags with dynamic weight adjustment
//! - **Performance Optimized**: Caching and lazy evaluation for large codebases

pub mod import_analysis;
pub mod scoring;
pub mod template_detection;

pub use scoring::{
    HeuristicScorer, HeuristicWeights, ScoreComponents, ScoringFeatures, WeightPreset,
};

pub use template_detection::{
    get_template_score_boost, is_template_file, TemplateDetectionMethod, TemplateDetector,
    TemplateEngine,
};

pub use import_analysis::{
    import_matches_file, CentralityCalculator, ImportGraph, ImportGraphBuilder,
};

use scribe_core::Result;
use std::collections::HashMap;

/// Main entry point for the heuristic scoring system
#[derive(Debug)]
pub struct HeuristicSystem {
    /// Core file scorer
    scorer: HeuristicScorer,
    /// Template detection engine
    template_detector: TemplateDetector,
}

impl HeuristicSystem {
    /// Create a new heuristic system with default configuration
    pub fn new() -> Result<Self> {
        Ok(Self {
            scorer: HeuristicScorer::new(HeuristicWeights::default()),
            template_detector: TemplateDetector::new()?,
        })
    }

    /// Create with custom weights
    pub fn with_weights(weights: HeuristicWeights) -> Result<Self> {
        Ok(Self {
            scorer: HeuristicScorer::new(weights),
            template_detector: TemplateDetector::new()?,
        })
    }

    /// Create with V2 features enabled
    pub fn with_v2_features() -> Result<Self> {
        Ok(Self {
            scorer: HeuristicScorer::new(HeuristicWeights::with_v2_features()),
            template_detector: TemplateDetector::new()?,
        })
    }

    /// Score a single file within the context of all scanned files
    pub fn score_file<T>(&mut self, file: &T, all_files: &[T]) -> Result<ScoreComponents>
    where
        T: ScanResult,
    {
        self.scorer.score_file(file, all_files)
    }

    /// Score all files and return ranked results
    pub fn score_all_files<T>(&mut self, files: &[T]) -> Result<Vec<(usize, ScoreComponents)>>
    where
        T: ScanResult,
    {
        self.scorer.score_all_files(files)
    }

    /// Get top-K files by heuristic score
    pub fn get_top_files<T>(
        &mut self,
        files: &[T],
        top_k: usize,
    ) -> Result<Vec<(usize, ScoreComponents)>>
    where
        T: ScanResult,
    {
        Ok(self
            .score_all_files(files)?
            .into_iter()
            .take(top_k)
            .collect())
    }

    /// Get template score boost for a file path
    pub fn get_template_boost(&self, file_path: &str) -> Result<f64> {
        self.template_detector.get_score_boost(file_path)
    }

    /// Check if two imports match (for import graph construction)
    pub fn import_matches(&self, import_name: &str, file_path: &str) -> bool {
        import_analysis::import_matches_file(import_name, file_path)
    }
}

impl Default for HeuristicSystem {
    fn default() -> Self {
        Self::new().expect("Failed to create HeuristicSystem")
    }
}

/// Trait that scan results must implement for heuristic scoring
pub trait ScanResult {
    /// Get the file path
    fn path(&self) -> &str;

    /// Get the relative path from repository root
    fn relative_path(&self) -> &str;

    /// Get file depth (directory nesting level)
    fn depth(&self) -> usize;

    /// Check if this is a documentation file
    fn is_docs(&self) -> bool;

    /// Check if this is a README file
    fn is_readme(&self) -> bool;

    /// Check if this is a test file
    fn is_test(&self) -> bool;

    /// Check if this is an entrypoint file (main, index, etc.)
    fn is_entrypoint(&self) -> bool;

    /// Check if this file contains examples
    fn has_examples(&self) -> bool;

    /// Get the priority boost value (from scanner)
    fn priority_boost(&self) -> f64;

    /// Get the churn score (git activity)
    fn churn_score(&self) -> f64;

    /// Get centrality in score (PageRank)
    fn centrality_in(&self) -> f64;

    /// Get list of import statements
    fn imports(&self) -> Option<&[String]>;

    /// Get document analysis results (if available)
    fn doc_analysis(&self) -> Option<&DocumentAnalysis>;
}

/// Document analysis results for scoring
#[derive(Debug, Clone)]
pub struct DocumentAnalysis {
    /// Number of headings in the document
    pub heading_count: usize,
    /// Number of table-of-contents indicators
    pub toc_indicators: usize,
    /// Number of links in the document
    pub link_count: usize,
    /// Number of code blocks
    pub code_block_count: usize,
    /// Whether the document appears well-structured
    pub is_well_structured: bool,
}

impl DocumentAnalysis {
    pub fn new() -> Self {
        Self {
            heading_count: 0,
            toc_indicators: 0,
            link_count: 0,
            code_block_count: 0,
            is_well_structured: false,
        }
    }

    /// Calculate structure score based on analysis
    pub fn structure_score(&self) -> f64 {
        let mut score = 0.0;

        // Heading structure bonus
        if self.heading_count > 0 {
            score += (self.heading_count as f64 / 10.0).min(0.5);
        }

        // TOC indicates well-organized document
        if self.toc_indicators > 0 {
            score += 0.3;
        }

        // Links indicate reference document
        if self.link_count > 0 {
            score += (self.link_count as f64 / 20.0).min(0.3);
        }

        // Code blocks in docs indicate technical documentation
        if self.code_block_count > 0 {
            score += (self.code_block_count as f64 / 10.0).min(0.2);
        }

        score
    }
}

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

/// Performance metrics for the heuristic system
#[derive(Debug, Clone)]
pub struct HeuristicMetrics {
    /// Number of files processed
    pub files_processed: usize,
    /// Total processing time in milliseconds
    pub processing_time_ms: u64,
    /// Import graph construction time
    pub import_graph_time_ms: u64,
    /// Template detection time
    pub template_detection_time_ms: u64,
    /// Average time per file
    pub avg_time_per_file_ms: f64,
    /// Cache hit rates
    pub cache_hit_rates: HashMap<String, f64>,
}

impl HeuristicMetrics {
    pub fn new() -> Self {
        Self {
            files_processed: 0,
            processing_time_ms: 0,
            import_graph_time_ms: 0,
            template_detection_time_ms: 0,
            avg_time_per_file_ms: 0.0,
            cache_hit_rates: HashMap::new(),
        }
    }

    pub fn finalize(&mut self) {
        if self.files_processed > 0 {
            self.avg_time_per_file_ms =
                self.processing_time_ms as f64 / self.files_processed as f64;
        }
    }
}

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

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

    #[test]
    fn test_heuristic_system_creation() {
        let system = HeuristicSystem::new();
        assert!(system.is_ok());

        let v2_system = HeuristicSystem::with_v2_features();
        assert!(v2_system.is_ok());
    }

    #[test]
    fn test_document_analysis() {
        let mut doc = DocumentAnalysis::new();
        doc.heading_count = 5;
        doc.link_count = 10;
        doc.code_block_count = 3;

        let score = doc.structure_score();
        assert!(score > 0.0);
        assert!(score < 2.0); // Should be reasonable
    }

    #[test]
    fn test_metrics() {
        let mut metrics = HeuristicMetrics::new();
        metrics.files_processed = 100;
        metrics.processing_time_ms = 500;
        metrics.finalize();

        assert_eq!(metrics.avg_time_per_file_ms, 5.0);
    }
}