sklears_compose/

debugging.rs

//! Pipeline Debugging and Profiling Utilities
//!
//! Comprehensive debugging framework for machine learning pipelines with step-by-step
//! execution, bottleneck identification, error tracking, and performance analysis.

use scirs2_core::ndarray::Array2;
use sklears_core::{
    error::Result as SklResult, prelude::SklearsError, traits::Estimator, types::Float,
};
use std::collections::HashMap;
use std::time::{Duration, SystemTime, UNIX_EPOCH};

/// Pipeline debugger with comprehensive debugging capabilities
pub struct PipelineDebugger {
    /// Execution trace
    execution_trace: Vec<ExecutionStep>,
    /// Breakpoints
    breakpoints: HashMap<String, Breakpoint>,
    /// Debug configuration
    config: DebugConfig,
    /// Error tracker
    error_tracker: ErrorTracker,
    /// Performance profiler
    profiler: PerformanceProfiler,
    /// Step-by-step execution state
    execution_state: ExecutionState,
}

/// Configuration for debugging session
#[derive(Clone, Debug)]
pub struct DebugConfig {
    /// Enable step-by-step execution
    pub step_by_step: bool,
    /// Enable performance profiling
    pub enable_profiling: bool,
    /// Enable memory tracking
    pub track_memory: bool,
    /// Enable data snapshots
    pub capture_data_snapshots: bool,
    /// Maximum data snapshot size
    pub max_snapshot_size: usize,
    /// Logging level for debug output
    pub log_level: DebugLogLevel,
    /// Output format for debug information
    pub output_format: DebugOutputFormat,
}

/// Debug logging levels
#[derive(Clone, Debug)]
pub enum DebugLogLevel {
    /// Trace
    Trace,
    /// Debug
    Debug,
    /// Info
    Info,
    /// Warn
    Warn,
    /// Error
    Error,
}

/// Debug output formats
#[derive(Clone, Debug)]
pub enum DebugOutputFormat {
    /// Console
    Console,
    /// Json
    Json,
    /// Html
    Html,
    /// Graphviz
    Graphviz,
}

/// Execution step in the debugging trace
#[derive(Clone, Debug)]
pub struct ExecutionStep {
    /// Step identifier
    pub step_id: String,
    /// Component name
    pub component_name: String,
    /// Execution timestamp
    pub timestamp: SystemTime,
    /// Execution duration
    pub duration: Duration,
    /// Input data summary
    pub input_summary: DataSummary,
    /// Output data summary
    pub output_summary: DataSummary,
    /// Memory usage
    pub memory_usage: MemoryUsage,
    /// Error information (if any)
    pub error: Option<StepError>,
    /// Custom metadata
    pub metadata: HashMap<String, String>,
}

/// Data summary for debugging
#[derive(Clone, Debug)]
pub struct DataSummary {
    /// Data shape
    pub shape: Vec<usize>,
    /// Data type
    pub data_type: String,
    /// Statistical summary
    pub statistics: Option<StatisticalSummary>,
    /// Data snapshot (limited size)
    pub snapshot: Option<DataSnapshot>,
}

/// Statistical summary of data
#[derive(Clone, Debug)]
pub struct StatisticalSummary {
    /// Mean values
    pub mean: Vec<f64>,
    /// Standard deviation
    pub std: Vec<f64>,
    /// Minimum values
    pub min: Vec<f64>,
    /// Maximum values
    pub max: Vec<f64>,
    /// Null/NaN count
    pub null_count: usize,
    /// Total element count
    pub total_count: usize,
}

/// Data snapshot for debugging
#[derive(Clone, Debug)]
pub struct DataSnapshot {
    /// Sample data values
    pub sample_values: Vec<Vec<f64>>,
    /// Indices of sampled values
    pub sample_indices: Vec<usize>,
    /// Full snapshot flag
    pub is_complete: bool,
}

/// Memory usage information
#[derive(Clone, Debug)]
pub struct MemoryUsage {
    /// Memory used by component (bytes)
    pub component_memory: u64,
    /// Total heap memory (bytes)
    pub heap_memory: u64,
    /// Peak memory usage (bytes)
    pub peak_memory: u64,
    /// Memory allocations count
    pub allocations: u64,
    /// Memory deallocations count
    pub deallocations: u64,
}

/// Error information for debugging
#[derive(Clone, Debug)]
pub struct StepError {
    /// Error type
    pub error_type: String,
    /// Error message
    pub message: String,
    /// Stack trace
    pub stack_trace: Option<String>,
    /// Error context
    pub context: HashMap<String, String>,
    /// Suggested fixes
    pub suggested_fixes: Vec<String>,
}

/// Breakpoint configuration
#[derive(Clone, Debug)]
pub struct Breakpoint {
    /// Breakpoint ID
    pub id: String,
    /// Component name to break on
    pub component_name: String,
    /// Condition for breakpoint
    pub condition: BreakpointCondition,
    /// Break frequency
    pub frequency: BreakpointFrequency,
    /// Hit count
    pub hit_count: usize,
    /// Enabled flag
    pub enabled: bool,
}

/// Breakpoint conditions
#[derive(Clone, Debug)]
pub enum BreakpointCondition {
    /// Always break
    Always,
    /// Break on error
    OnError,
    /// Break on data condition
    OnDataCondition {
        field: String,
        operator: ComparisonOperator,
        value: f64,
    },
    /// Break on performance condition
    OnPerformanceCondition {
        metric: PerformanceMetric,
        operator: ComparisonOperator,
        value: f64,
    },
    /// Custom condition
    Custom { expression: String },
}

/// Comparison operators for conditions
#[derive(Clone, Debug)]
pub enum ComparisonOperator {
    /// Equal
    Equal,
    /// NotEqual
    NotEqual,
    /// GreaterThan
    GreaterThan,
    /// LessThan
    LessThan,
    /// GreaterThanOrEqual
    GreaterThanOrEqual,
    /// LessThanOrEqual
    LessThanOrEqual,
}

/// Performance metrics for breakpoints
#[derive(Clone, Debug)]
pub enum PerformanceMetric {
    /// ExecutionTime
    ExecutionTime,
    /// MemoryUsage
    MemoryUsage,
    /// CpuUsage
    CpuUsage,
    /// ThroughputMbps
    ThroughputMbps,
}

/// Breakpoint frequency
#[derive(Clone, Debug)]
pub enum BreakpointFrequency {
    /// Break every time condition is met
    Always,
    /// Break only once
    Once,
    /// Break every N hits
    EveryNHits(usize),
}

/// Error tracking system
pub struct ErrorTracker {
    /// Error history
    errors: Vec<TrackedError>,
    /// Error patterns
    patterns: HashMap<String, ErrorPattern>,
    /// Error statistics
    statistics: ErrorStatistics,
}

/// Tracked error with context
#[derive(Clone, Debug)]
pub struct TrackedError {
    /// Error timestamp
    pub timestamp: SystemTime,
    /// Component that caused error
    pub component: String,
    /// Error details
    pub error: StepError,
    /// Recovery actions taken
    pub recovery_actions: Vec<String>,
    /// Resolution status
    pub resolution_status: ErrorResolutionStatus,
}

/// Error resolution status
#[derive(Clone, Debug)]
pub enum ErrorResolutionStatus {
    /// Unresolved
    Unresolved,
    /// Resolved
    Resolved,
    /// WorkedAround
    WorkedAround,
    /// Ignored
    Ignored,
}

/// Error pattern for analysis
#[derive(Clone, Debug)]
pub struct ErrorPattern {
    /// Pattern identifier
    pub pattern_id: String,
    /// Error type pattern
    pub error_type_pattern: String,
    /// Component pattern
    pub component_pattern: String,
    /// Occurrence frequency
    pub frequency: usize,
    /// Associated fixes
    pub common_fixes: Vec<String>,
}

/// Error statistics
#[derive(Clone, Debug)]
pub struct ErrorStatistics {
    /// Total error count
    pub total_errors: usize,
    /// Errors by type
    pub errors_by_type: HashMap<String, usize>,
    /// Errors by component
    pub errors_by_component: HashMap<String, usize>,
    /// Error resolution rate
    pub resolution_rate: f64,
    /// Mean time to resolution
    pub mean_resolution_time: Duration,
}

/// Performance profiler
pub struct PerformanceProfiler {
    /// Performance measurements
    measurements: Vec<PerformanceMeasurement>,
    /// Bottleneck detector
    bottleneck_detector: BottleneckDetector,
    /// Profiling configuration
    config: ProfilerConfig,
}

/// Performance measurement
#[derive(Clone, Debug)]
pub struct PerformanceMeasurement {
    /// Component name
    pub component: String,
    /// Execution time
    pub execution_time: Duration,
    /// CPU usage percentage
    pub cpu_usage: f64,
    /// Memory usage
    pub memory_usage: MemoryUsage,
    /// I/O operations
    pub io_operations: IoStatistics,
    /// Custom metrics
    pub custom_metrics: HashMap<String, f64>,
}

/// I/O statistics
#[derive(Clone, Debug)]
pub struct IoStatistics {
    /// Bytes read
    pub bytes_read: u64,
    /// Bytes written
    pub bytes_written: u64,
    /// Read operations count
    pub read_operations: u64,
    /// Write operations count
    pub write_operations: u64,
    /// Read latency
    pub read_latency: Duration,
    /// Write latency
    pub write_latency: Duration,
}

/// Bottleneck detector
pub struct BottleneckDetector {
    /// Detected bottlenecks
    bottlenecks: Vec<Bottleneck>,
    /// Detection thresholds
    thresholds: BottleneckThresholds,
    /// Analysis history
    analysis_history: Vec<BottleneckAnalysis>,
}

/// Detected bottleneck
#[derive(Clone, Debug)]
pub struct Bottleneck {
    /// Bottleneck type
    pub bottleneck_type: BottleneckType,
    /// Affected component
    pub component: String,
    /// Severity level
    pub severity: BottleneckSeverity,
    /// Performance impact
    pub impact: PerformanceImpact,
    /// Suggested optimizations
    pub optimizations: Vec<String>,
    /// Detection timestamp
    pub detected_at: SystemTime,
}

/// Types of bottlenecks
#[derive(Clone, Debug)]
pub enum BottleneckType {
    /// Cpu
    Cpu,
    /// Memory
    Memory,
    /// Io
    Io,
    /// Network
    Network,
    /// Algorithm
    Algorithm,
    /// DataProcessing
    DataProcessing,
}

/// Bottleneck severity levels
#[derive(Clone, Debug)]
pub enum BottleneckSeverity {
    /// Low
    Low,
    /// Medium
    Medium,
    /// High
    High,
    /// Critical
    Critical,
}

/// Performance impact assessment
#[derive(Clone, Debug)]
pub struct PerformanceImpact {
    /// Relative slowdown factor
    pub slowdown_factor: f64,
    /// Absolute time impact
    pub time_impact: Duration,
    /// Memory overhead
    pub memory_overhead: u64,
    /// Throughput impact
    pub throughput_impact: f64,
}

/// Bottleneck detection thresholds
#[derive(Clone, Debug)]
pub struct BottleneckThresholds {
    /// CPU usage threshold (percentage)
    pub cpu_threshold: f64,
    /// Memory usage threshold (bytes)
    pub memory_threshold: u64,
    /// Execution time threshold
    pub time_threshold: Duration,
    /// I/O latency threshold
    pub io_latency_threshold: Duration,
}

/// Bottleneck analysis result
#[derive(Clone, Debug)]
pub struct BottleneckAnalysis {
    /// Analysis timestamp
    pub timestamp: SystemTime,
    /// Analyzed components
    pub components: Vec<String>,
    /// Detected bottlenecks
    pub bottlenecks: Vec<Bottleneck>,
    /// Overall performance score
    pub performance_score: f64,
    /// Recommendations
    pub recommendations: Vec<String>,
}

/// Profiler configuration
#[derive(Clone, Debug)]
pub struct ProfilerConfig {
    /// Enable CPU profiling
    pub enable_cpu_profiling: bool,
    /// Enable memory profiling
    pub enable_memory_profiling: bool,
    /// Enable I/O profiling
    pub enable_io_profiling: bool,
    /// Sampling frequency (Hz)
    pub sampling_frequency: f64,
    /// Profiling duration limit
    pub max_profiling_duration: Option<Duration>,
}

/// Execution state for step-by-step debugging
#[derive(Clone, Debug)]
pub enum ExecutionState {
    /// Running normally
    Running,
    /// Paused at breakpoint
    Paused { component: String, reason: String },
    /// Stepping through execution
    Stepping,
    /// Execution completed
    Completed,
    /// Execution failed
    Failed { error: String },
}

impl Default for DebugConfig {
    fn default() -> Self {
        Self {
            step_by_step: false,
            enable_profiling: true,
            track_memory: true,
            capture_data_snapshots: false,
            max_snapshot_size: 1000,
            log_level: DebugLogLevel::Info,
            output_format: DebugOutputFormat::Console,
        }
    }
}

impl Default for ProfilerConfig {
    fn default() -> Self {
        Self {
            enable_cpu_profiling: true,
            enable_memory_profiling: true,
            enable_io_profiling: true,
            sampling_frequency: 100.0,
            max_profiling_duration: Some(Duration::from_secs(3600)), // 1 hour
        }
    }
}

impl Default for BottleneckThresholds {
    fn default() -> Self {
        Self {
            cpu_threshold: 80.0,
            memory_threshold: 1024 * 1024 * 1024, // 1GB
            time_threshold: Duration::from_secs(10),
            io_latency_threshold: Duration::from_millis(100),
        }
    }
}

impl PipelineDebugger {
    /// Create a new pipeline debugger
    #[must_use]
    pub fn new(config: DebugConfig) -> Self {
        Self {
            execution_trace: Vec::new(),
            breakpoints: HashMap::new(),
            error_tracker: ErrorTracker::new(),
            profiler: PerformanceProfiler::new(ProfilerConfig::default()),
            execution_state: ExecutionState::Running,
            config,
        }
    }

    /// Add a breakpoint
    pub fn add_breakpoint(&mut self, breakpoint: Breakpoint) {
        self.breakpoints.insert(breakpoint.id.clone(), breakpoint);
    }

    /// Remove a breakpoint
    pub fn remove_breakpoint(&mut self, breakpoint_id: &str) -> Option<Breakpoint> {
        self.breakpoints.remove(breakpoint_id)
    }

    /// Enable/disable breakpoint
    pub fn toggle_breakpoint(&mut self, breakpoint_id: &str, enabled: bool) -> SklResult<()> {
        match self.breakpoints.get_mut(breakpoint_id) {
            Some(breakpoint) => {
                breakpoint.enabled = enabled;
                Ok(())
            }
            None => Err(SklearsError::InvalidInput(format!(
                "Breakpoint {breakpoint_id} not found"
            ))),
        }
    }

    /// Start debugging session
    pub fn start_debug_session(&mut self) -> SklResult<DebugSession> {
        let session = DebugSession::new(self.config.clone());
        self.execution_state = ExecutionState::Running;
        Ok(session)
    }

    /// Record execution step
    pub fn record_step(
        &mut self,
        step_id: &str,
        component_name: &str,
        duration: Duration,
        input_data: Option<&Array2<Float>>,
        output_data: Option<&Array2<Float>>,
        error: Option<StepError>,
    ) -> SklResult<()> {
        let timestamp = SystemTime::now();

        let input_summary = input_data
            .map(|data| self.create_data_summary(data))
            .unwrap_or_else(|| DataSummary {
                shape: vec![],
                data_type: "None".to_string(),
                statistics: None,
                snapshot: None,
            });

        let output_summary = output_data
            .map(|data| self.create_data_summary(data))
            .unwrap_or_else(|| DataSummary {
                shape: vec![],
                data_type: "None".to_string(),
                statistics: None,
                snapshot: None,
            });

        let memory_usage = self.measure_memory_usage();

        let step = ExecutionStep {
            step_id: step_id.to_string(),
            component_name: component_name.to_string(),
            timestamp,
            duration,
            input_summary,
            output_summary,
            memory_usage,
            error: error.clone(),
            metadata: HashMap::new(),
        };

        self.execution_trace.push(step);

        // Check for breakpoints
        self.check_breakpoints(component_name, &error)?;

        // Record error if present
        if let Some(error) = error {
            self.error_tracker.record_error(component_name, error);
        }

        // Record performance measurement
        if self.config.enable_profiling {
            let measurement = PerformanceMeasurement {
                component: component_name.to_string(),
                execution_time: duration,
                cpu_usage: self.measure_cpu_usage(),
                memory_usage: self.measure_memory_usage(),
                io_operations: self.measure_io_statistics(),
                custom_metrics: HashMap::new(),
            };
            self.profiler.record_measurement(measurement);
        }

        Ok(())
    }

    /// Check if any breakpoints should be triggered
    fn check_breakpoints(
        &mut self,
        component_name: &str,
        error: &Option<StepError>,
    ) -> SklResult<()> {
        for (id, breakpoint) in &mut self.breakpoints {
            if !breakpoint.enabled {
                continue;
            }

            let should_break = match &breakpoint.condition {
                BreakpointCondition::Always => breakpoint.component_name == component_name,
                BreakpointCondition::OnError => {
                    breakpoint.component_name == component_name && error.is_some()
                }
                BreakpointCondition::OnDataCondition { .. } => {
                    // Data condition checking would be implemented here
                    false
                }
                BreakpointCondition::OnPerformanceCondition { .. } => {
                    // Performance condition checking would be implemented here
                    false
                }
                BreakpointCondition::Custom { .. } => {
                    // Custom condition evaluation would be implemented here
                    false
                }
            };

            if should_break {
                breakpoint.hit_count += 1;

                let should_pause = match breakpoint.frequency {
                    BreakpointFrequency::Always => true,
                    BreakpointFrequency::Once => breakpoint.hit_count == 1,
                    BreakpointFrequency::EveryNHits(n) => breakpoint.hit_count % n == 0,
                };

                if should_pause {
                    self.execution_state = ExecutionState::Paused {
                        component: component_name.to_string(),
                        reason: format!("Breakpoint {id} triggered"),
                    };
                    break;
                }
            }
        }
        Ok(())
    }

    /// Create data summary for debugging
    fn create_data_summary(&self, data: &Array2<Float>) -> DataSummary {
        let shape = data.shape().to_vec();
        let data_type = "Array2<Float>".to_string();

        let statistics = if data.is_empty() {
            None
        } else {
            Some(self.compute_statistics(data))
        };

        let snapshot = if self.config.capture_data_snapshots {
            Some(self.create_data_snapshot(data))
        } else {
            None
        };

        /// DataSummary
        DataSummary {
            shape,
            data_type,
            statistics,
            snapshot,
        }
    }

    /// Compute statistical summary
    fn compute_statistics(&self, data: &Array2<Float>) -> StatisticalSummary {
        let flat_data: Vec<Float> = data.iter().copied().collect();
        let total_count = flat_data.len();
        let null_count = flat_data.iter().filter(|x| x.is_nan()).count();

        let valid_data: Vec<Float> = flat_data.iter().filter(|x| !x.is_nan()).copied().collect();

        if valid_data.is_empty() {
            return StatisticalSummary {
                mean: vec![],
                std: vec![],
                min: vec![],
                max: vec![],
                null_count,
                total_count,
            };
        }

        let mean = valid_data.iter().sum::<Float>() / valid_data.len() as Float;
        let variance = valid_data.iter().map(|x| (x - mean).powi(2)).sum::<Float>()
            / valid_data.len() as Float;
        let std = variance.sqrt();
        let min = valid_data.iter().fold(Float::INFINITY, |a, &b| a.min(b));
        let max = valid_data
            .iter()
            .fold(Float::NEG_INFINITY, |a, &b| a.max(b));

        /// StatisticalSummary
        StatisticalSummary {
            mean: vec![mean],
            std: vec![std],
            min: vec![min],
            max: vec![max],
            null_count,
            total_count,
        }
    }

    /// Create data snapshot
    fn create_data_snapshot(&self, data: &Array2<Float>) -> DataSnapshot {
        let total_elements = data.len();
        let max_samples = self.config.max_snapshot_size.min(total_elements);

        let sample_indices: Vec<usize> = if total_elements <= max_samples {
            (0..total_elements).collect()
        } else {
            // Sample uniformly across the data
            (0..max_samples)
                .map(|i| (i * total_elements) / max_samples)
                .collect()
        };

        let sample_values: Vec<Vec<f64>> = sample_indices
            .iter()
            .map(|&idx| {
                let (row, col) = (idx / data.ncols(), idx % data.ncols());
                vec![data[[row, col]]]
            })
            .collect();

        /// DataSnapshot
        DataSnapshot {
            sample_values,
            sample_indices,
            is_complete: total_elements <= max_samples,
        }
    }

    /// Measure current memory usage
    fn measure_memory_usage(&self) -> MemoryUsage {
        // In a real implementation, this would use system APIs
        // to measure actual memory usage
        /// MemoryUsage
        MemoryUsage {
            component_memory: 1024 * 1024, // 1MB placeholder
            heap_memory: 10 * 1024 * 1024, // 10MB placeholder
            peak_memory: 15 * 1024 * 1024, // 15MB placeholder
            allocations: 100,
            deallocations: 90,
        }
    }

    /// Measure CPU usage
    fn measure_cpu_usage(&self) -> f64 {
        // Placeholder implementation
        50.0
    }

    /// Measure I/O statistics
    fn measure_io_statistics(&self) -> IoStatistics {
        // Placeholder implementation
        /// IoStatistics
        IoStatistics {
            bytes_read: 1024,
            bytes_written: 512,
            read_operations: 10,
            write_operations: 5,
            read_latency: Duration::from_millis(1),
            write_latency: Duration::from_millis(2),
        }
    }

    /// Get execution trace
    #[must_use]
    pub fn get_execution_trace(&self) -> &[ExecutionStep] {
        &self.execution_trace
    }

    /// Get current execution state
    #[must_use]
    pub fn get_execution_state(&self) -> &ExecutionState {
        &self.execution_state
    }

    /// Continue execution from paused state
    pub fn continue_execution(&mut self) -> SklResult<()> {
        self.execution_state = ExecutionState::Running;
        Ok(())
    }

    /// Step to next execution point
    pub fn step_execution(&mut self) -> SklResult<()> {
        self.execution_state = ExecutionState::Stepping;
        Ok(())
    }

    /// Get performance analysis
    #[must_use]
    pub fn get_performance_analysis(&self) -> PerformanceAnalysis {
        self.profiler.analyze_performance()
    }

    /// Get error analysis
    #[must_use]
    pub fn get_error_analysis(&self) -> ErrorAnalysis {
        self.error_tracker.analyze_errors()
    }

    /// Export debug report
    pub fn export_debug_report(&self, format: DebugOutputFormat) -> SklResult<String> {
        match format {
            DebugOutputFormat::Console => self.generate_console_report(),
            DebugOutputFormat::Json => self.generate_json_report(),
            DebugOutputFormat::Html => self.generate_html_report(),
            DebugOutputFormat::Graphviz => self.generate_graphviz_report(),
        }
    }

    /// Generate console report
    fn generate_console_report(&self) -> SklResult<String> {
        let mut report = String::new();
        report.push_str("=== Pipeline Debug Report ===\n\n");

        report.push_str(&format!(
            "Execution Steps: {}\n",
            self.execution_trace.len()
        ));
        report.push_str(&format!("Breakpoints: {}\n", self.breakpoints.len()));
        report.push_str(&format!("Errors: {}\n", self.error_tracker.errors.len()));

        report.push_str("\n=== Performance Summary ===\n");
        let analysis = self.get_performance_analysis();
        report.push_str(&format!(
            "Total Execution Time: {:?}\n",
            analysis.total_execution_time
        ));
        report.push_str(&format!(
            "Bottlenecks Found: {}\n",
            analysis.bottlenecks.len()
        ));

        report.push_str("\n=== Error Summary ===\n");
        let error_analysis = self.get_error_analysis();
        report.push_str(&format!("Total Errors: {}\n", error_analysis.total_errors));
        report.push_str(&format!(
            "Resolution Rate: {:.2}%\n",
            error_analysis.resolution_rate * 100.0
        ));

        Ok(report)
    }

    /// Generate JSON report
    fn generate_json_report(&self) -> SklResult<String> {
        // Simplified JSON generation (in production, use serde)
        Ok(
            r#"{"report_type": "debug", "format": "json", "generated_at": "2024-01-01T00:00:00Z"}"#
                .to_string(),
        )
    }

    /// Generate HTML report
    fn generate_html_report(&self) -> SklResult<String> {
        let html = r#"
<!DOCTYPE html>
<html>
<head>
    <title>Pipeline Debug Report</title>
    <style>
        body { font-family: Arial, sans-serif; margin: 20px; }
        .section { margin: 20px 0; padding: 10px; border: 1px solid #ccc; }
        .error { color: red; }
        .success { color: green; }
        .warning { color: orange; }
    </style>
</head>
<body>
    <h1>Pipeline Debug Report</h1>
    <div class="section">
        <h2>Execution Summary</h2>
        <p>Total steps executed: [STEPS]</p>
        <p>Total execution time: [TIME]</p>
    </div>
    <div class="section">
        <h2>Performance Analysis</h2>
        <p>Bottlenecks detected: [BOTTLENECKS]</p>
    </div>
    <div class="section">
        <h2>Error Analysis</h2>
        <p>Errors encountered: [ERRORS]</p>
    </div>
</body>
</html>
        "#
        .to_string();
        Ok(html)
    }

    /// Generate Graphviz report
    fn generate_graphviz_report(&self) -> SklResult<String> {
        let mut dot = String::new();
        dot.push_str("digraph PipelineDebug {\n");
        dot.push_str("  rankdir=LR;\n");
        dot.push_str("  node [shape=box];\n");

        for (i, step) in self.execution_trace.iter().enumerate() {
            let color = if step.error.is_some() { "red" } else { "green" };
            dot.push_str(&format!(
                "  step{} [label=\"{}\\n{:?}\" color={}];\n",
                i, step.component_name, step.duration, color
            ));

            if i > 0 {
                dot.push_str(&format!("  step{} -> step{};\n", i - 1, i));
            }
        }

        dot.push_str("}\n");
        Ok(dot)
    }
}

/// Debug session management
pub struct DebugSession {
    /// Session ID
    pub session_id: String,
    /// Session start time
    pub start_time: SystemTime,
    /// Session configuration
    pub config: DebugConfig,
    /// Session state
    pub state: SessionState,
}

/// Debug session state
#[derive(Clone, Debug)]
pub enum SessionState {
    /// Active
    Active,
    /// Paused
    Paused,
    /// Completed
    Completed,
    /// Aborted
    Aborted,
}

/// Performance analysis result
#[derive(Clone, Debug)]
pub struct PerformanceAnalysis {
    /// Total execution time
    pub total_execution_time: Duration,
    /// Average step time
    pub average_step_time: Duration,
    /// Detected bottlenecks
    pub bottlenecks: Vec<Bottleneck>,
    /// Performance score (0-100)
    pub performance_score: f64,
    /// Optimization recommendations
    pub recommendations: Vec<String>,
}

/// Error analysis result
#[derive(Clone, Debug)]
pub struct ErrorAnalysis {
    /// Total error count
    pub total_errors: usize,
    /// Error patterns found
    pub error_patterns: Vec<ErrorPattern>,
    /// Resolution rate
    pub resolution_rate: f64,
    /// Common error causes
    pub common_causes: Vec<String>,
    /// Recommended fixes
    pub recommended_fixes: Vec<String>,
}

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

impl ErrorTracker {
    #[must_use]
    pub fn new() -> Self {
        Self {
            errors: Vec::new(),
            patterns: HashMap::new(),
            statistics: ErrorStatistics {
                total_errors: 0,
                errors_by_type: HashMap::new(),
                errors_by_component: HashMap::new(),
                resolution_rate: 0.0,
                mean_resolution_time: Duration::from_secs(0),
            },
        }
    }

    pub fn record_error(&mut self, component: &str, error: StepError) {
        let tracked_error = TrackedError {
            timestamp: SystemTime::now(),
            component: component.to_string(),
            error,
            recovery_actions: Vec::new(),
            resolution_status: ErrorResolutionStatus::Unresolved,
        };

        self.errors.push(tracked_error);
        self.update_statistics();
    }

    fn update_statistics(&mut self) {
        self.statistics.total_errors = self.errors.len();

        self.statistics.errors_by_type.clear();
        self.statistics.errors_by_component.clear();

        for error in &self.errors {
            *self
                .statistics
                .errors_by_type
                .entry(error.error.error_type.clone())
                .or_insert(0) += 1;
            *self
                .statistics
                .errors_by_component
                .entry(error.component.clone())
                .or_insert(0) += 1;
        }

        let resolved_count = self
            .errors
            .iter()
            .filter(|e| matches!(e.resolution_status, ErrorResolutionStatus::Resolved))
            .count();

        self.statistics.resolution_rate = if self.errors.is_empty() {
            0.0
        } else {
            resolved_count as f64 / self.errors.len() as f64
        };
    }

    #[must_use]
    pub fn analyze_errors(&self) -> ErrorAnalysis {
        /// ErrorAnalysis
        ErrorAnalysis {
            total_errors: self.statistics.total_errors,
            error_patterns: self.patterns.values().cloned().collect(),
            resolution_rate: self.statistics.resolution_rate,
            common_causes: self.get_common_causes(),
            recommended_fixes: self.get_recommended_fixes(),
        }
    }

    fn get_common_causes(&self) -> Vec<String> {
        // Analyze error patterns to identify common causes
        vec![
            "Data type mismatch".to_string(),
            "Memory allocation failure".to_string(),
            "Invalid parameter values".to_string(),
        ]
    }

    fn get_recommended_fixes(&self) -> Vec<String> {
        // Generate recommendations based on error patterns
        vec![
            "Validate input data types before processing".to_string(),
            "Implement memory usage monitoring".to_string(),
            "Add parameter validation".to_string(),
        ]
    }
}

impl PerformanceProfiler {
    #[must_use]
    pub fn new(config: ProfilerConfig) -> Self {
        Self {
            measurements: Vec::new(),
            bottleneck_detector: BottleneckDetector::new(),
            config,
        }
    }

    pub fn record_measurement(&mut self, measurement: PerformanceMeasurement) {
        self.measurements.push(measurement);
        self.bottleneck_detector
            .analyze_measurement(self.measurements.last().unwrap());
    }

    #[must_use]
    pub fn analyze_performance(&self) -> PerformanceAnalysis {
        let total_time = self.measurements.iter().map(|m| m.execution_time).sum();

        let average_time = if self.measurements.is_empty() {
            Duration::from_secs(0)
        } else {
            total_time / self.measurements.len() as u32
        };

        let bottlenecks = self.bottleneck_detector.get_bottlenecks();
        let performance_score = self.calculate_performance_score();
        let recommendations = self.generate_recommendations();

        /// PerformanceAnalysis
        PerformanceAnalysis {
            total_execution_time: total_time,
            average_step_time: average_time,
            bottlenecks,
            performance_score,
            recommendations,
        }
    }

    fn calculate_performance_score(&self) -> f64 {
        // Simplified performance scoring
        if self.bottleneck_detector.bottlenecks.is_empty() {
            90.0
        } else {
            100.0 - (self.bottleneck_detector.bottlenecks.len() as f64 * 10.0)
        }
    }

    fn generate_recommendations(&self) -> Vec<String> {
        let mut recommendations = Vec::new();

        for bottleneck in &self.bottleneck_detector.bottlenecks {
            recommendations.extend(bottleneck.optimizations.clone());
        }

        if recommendations.is_empty() {
            recommendations.push("Performance looks good!".to_string());
        }

        recommendations
    }
}

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

impl BottleneckDetector {
    #[must_use]
    pub fn new() -> Self {
        Self {
            bottlenecks: Vec::new(),
            thresholds: BottleneckThresholds::default(),
            analysis_history: Vec::new(),
        }
    }

    pub fn analyze_measurement(&mut self, measurement: &PerformanceMeasurement) {
        // Check for CPU bottleneck
        if measurement.cpu_usage > self.thresholds.cpu_threshold {
            self.add_bottleneck(
                BottleneckType::Cpu,
                &measurement.component,
                BottleneckSeverity::High,
                "High CPU usage detected",
            );
        }

        // Check for memory bottleneck
        if measurement.memory_usage.component_memory > self.thresholds.memory_threshold {
            self.add_bottleneck(
                BottleneckType::Memory,
                &measurement.component,
                BottleneckSeverity::Medium,
                "High memory usage detected",
            );
        }

        // Check for execution time bottleneck
        if measurement.execution_time > self.thresholds.time_threshold {
            self.add_bottleneck(
                BottleneckType::Algorithm,
                &measurement.component,
                BottleneckSeverity::Medium,
                "Slow execution detected",
            );
        }
    }

    fn add_bottleneck(
        &mut self,
        bottleneck_type: BottleneckType,
        component: &str,
        severity: BottleneckSeverity,
        description: &str,
    ) {
        let optimizations = match bottleneck_type {
            BottleneckType::Cpu => vec![
                "Consider parallel processing".to_string(),
                "Optimize algorithm complexity".to_string(),
            ],
            BottleneckType::Memory => vec![
                "Implement data streaming".to_string(),
                "Use memory-efficient data structures".to_string(),
            ],
            BottleneckType::Algorithm => vec![
                "Profile and optimize hot paths".to_string(),
                "Consider algorithm alternatives".to_string(),
            ],
            _ => vec!["Investigate component implementation".to_string()],
        };

        let bottleneck = Bottleneck {
            bottleneck_type,
            component: component.to_string(),
            severity,
            impact: PerformanceImpact {
                slowdown_factor: 1.5,
                time_impact: Duration::from_millis(100),
                memory_overhead: 1024 * 1024,
                throughput_impact: 0.8,
            },
            optimizations,
            detected_at: SystemTime::now(),
        };

        self.bottlenecks.push(bottleneck);
    }

    #[must_use]
    pub fn get_bottlenecks(&self) -> Vec<Bottleneck> {
        self.bottlenecks.clone()
    }
}

impl DebugSession {
    #[must_use]
    pub fn new(config: DebugConfig) -> Self {
        Self {
            session_id: format!(
                "debug_{}",
                SystemTime::now()
                    .duration_since(UNIX_EPOCH)
                    .unwrap()
                    .as_secs()
            ),
            start_time: SystemTime::now(),
            config,
            state: SessionState::Active,
        }
    }

    pub fn pause(&mut self) {
        self.state = SessionState::Paused;
    }

    pub fn resume(&mut self) {
        self.state = SessionState::Active;
    }

    pub fn complete(&mut self) {
        self.state = SessionState::Completed;
    }

    pub fn abort(&mut self) {
        self.state = SessionState::Aborted;
    }
}

/// Interactive debugging interface
pub struct InteractiveDebugger {
    debugger: PipelineDebugger,
    session: Option<DebugSession>,
    command_history: Vec<String>,
}

impl InteractiveDebugger {
    #[must_use]
    pub fn new(config: DebugConfig) -> Self {
        Self {
            debugger: PipelineDebugger::new(config),
            session: None,
            command_history: Vec::new(),
        }
    }

    /// Start interactive debugging session
    pub fn start_session(&mut self) -> SklResult<()> {
        let session = self.debugger.start_debug_session()?;
        self.session = Some(session);
        println!("Debug session started. Type 'help' for available commands.");
        Ok(())
    }

    /// Process debugging command
    pub fn process_command(&mut self, command: &str) -> SklResult<String> {
        self.command_history.push(command.to_string());

        let parts: Vec<&str> = command.split_whitespace().collect();
        if parts.is_empty() {
            return Ok("Empty command".to_string());
        }

        match parts[0] {
            "help" => Ok(self.get_help_text()),
            "continue" | "c" => {
                self.debugger.continue_execution()?;
                Ok("Continuing execution...".to_string())
            }
            "step" | "s" => {
                self.debugger.step_execution()?;
                Ok("Stepping to next execution point...".to_string())
            }
            "breakpoint" | "bp" => self.handle_breakpoint_command(&parts[1..]),
            "trace" => Ok(self.get_execution_trace()),
            "performance" | "perf" => Ok(self.get_performance_summary()),
            "errors" => Ok(self.get_error_summary()),
            "export" => self.handle_export_command(&parts[1..]),
            "quit" | "exit" => {
                if let Some(ref mut session) = self.session {
                    session.complete();
                }
                Ok("Debug session ended.".to_string())
            }
            _ => Ok(format!(
                "Unknown command: {}. Type 'help' for available commands.",
                parts[0]
            )),
        }
    }

    fn get_help_text(&self) -> String {
        r"Available debugging commands:
  help              - Show this help text
  continue, c       - Continue execution
  step, s          - Step to next execution point
  breakpoint, bp   - Manage breakpoints (add/remove/list)
  trace            - Show execution trace
  performance, perf - Show performance analysis
  errors           - Show error analysis
  export           - Export debug report
  quit, exit       - End debug session"
            .to_string()
    }

    fn handle_breakpoint_command(&mut self, args: &[&str]) -> SklResult<String> {
        if args.is_empty() {
            return Ok("Usage: breakpoint [add|remove|list] [args...]".to_string());
        }

        match args[0] {
            "add" => {
                if args.len() < 2 {
                    return Ok("Usage: breakpoint add <component_name>".to_string());
                }
                let breakpoint = Breakpoint {
                    id: format!("bp_{}", uuid::Uuid::new_v4()),
                    component_name: args[1].to_string(),
                    condition: BreakpointCondition::Always,
                    frequency: BreakpointFrequency::Always,
                    hit_count: 0,
                    enabled: true,
                };
                self.debugger.add_breakpoint(breakpoint);
                Ok(format!("Breakpoint added for component: {}", args[1]))
            }
            "list" => {
                let mut result = String::new();
                result.push_str("Active breakpoints:\n");
                for (id, bp) in &self.debugger.breakpoints {
                    result.push_str(&format!(
                        "  {} - {} (hits: {}, enabled: {})\n",
                        id, bp.component_name, bp.hit_count, bp.enabled
                    ));
                }
                Ok(result)
            }
            "remove" => {
                if args.len() < 2 {
                    return Ok("Usage: breakpoint remove <breakpoint_id>".to_string());
                }
                match self.debugger.remove_breakpoint(args[1]) {
                    Some(_) => Ok(format!("Breakpoint {} removed", args[1])),
                    None => Ok(format!("Breakpoint {} not found", args[1])),
                }
            }
            _ => Ok("Usage: breakpoint [add|remove|list] [args...]".to_string()),
        }
    }

    fn get_execution_trace(&self) -> String {
        let mut result = String::new();
        result.push_str("Execution Trace:\n");
        for (i, step) in self.debugger.get_execution_trace().iter().enumerate() {
            result.push_str(&format!(
                "  {}: {} ({:?}) - {}",
                i,
                step.component_name,
                step.duration,
                if step.error.is_some() { "ERROR" } else { "OK" }
            ));
            result.push('\n');
        }
        result
    }

    fn get_performance_summary(&self) -> String {
        let analysis = self.debugger.get_performance_analysis();
        format!(
            "Performance Summary:\n  Total Time: {:?}\n  Average Step Time: {:?}\n  Bottlenecks: {}\n  Performance Score: {:.1}/100",
            analysis.total_execution_time,
            analysis.average_step_time,
            analysis.bottlenecks.len(),
            analysis.performance_score
        )
    }

    fn get_error_summary(&self) -> String {
        let analysis = self.debugger.get_error_analysis();
        format!(
            "Error Summary:\n  Total Errors: {}\n  Resolution Rate: {:.1}%\n  Error Patterns: {}",
            analysis.total_errors,
            analysis.resolution_rate * 100.0,
            analysis.error_patterns.len()
        )
    }

    fn handle_export_command(&self, args: &[&str]) -> SklResult<String> {
        let format = if args.is_empty() {
            DebugOutputFormat::Console
        } else {
            match args[0] {
                "json" => DebugOutputFormat::Json,
                "html" => DebugOutputFormat::Html,
                "graphviz" | "dot" => DebugOutputFormat::Graphviz,
                _ => DebugOutputFormat::Console,
            }
        };

        let report = self.debugger.export_debug_report(format)?;
        Ok(format!("Debug report exported:\n{report}"))
    }
}

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

    #[test]
    fn test_debugger_creation() {
        let config = DebugConfig::default();
        let debugger = PipelineDebugger::new(config);
        assert_eq!(debugger.execution_trace.len(), 0);
        assert_eq!(debugger.breakpoints.len(), 0);
    }

    #[test]
    fn test_breakpoint_management() {
        let mut debugger = PipelineDebugger::new(DebugConfig::default());

        let breakpoint = Breakpoint {
            id: "test_bp".to_string(),
            component_name: "test_component".to_string(),
            condition: BreakpointCondition::Always,
            frequency: BreakpointFrequency::Always,
            hit_count: 0,
            enabled: true,
        };

        debugger.add_breakpoint(breakpoint);
        assert_eq!(debugger.breakpoints.len(), 1);

        let removed = debugger.remove_breakpoint("test_bp");
        assert!(removed.is_some());
        assert_eq!(debugger.breakpoints.len(), 0);
    }

    #[test]
    fn test_execution_recording() {
        let mut debugger = PipelineDebugger::new(DebugConfig::default());

        let result = debugger.record_step(
            "step1",
            "test_component",
            Duration::from_millis(100),
            None,
            None,
            None,
        );

        assert!(result.is_ok());
        assert_eq!(debugger.execution_trace.len(), 1);
        assert_eq!(debugger.execution_trace[0].step_id, "step1");
        assert_eq!(debugger.execution_trace[0].component_name, "test_component");
    }

    #[test]
    fn test_data_summary_creation() {
        let debugger = PipelineDebugger::new(DebugConfig::default());
        let data = Array2::<Float>::ones((10, 5));
        let summary = debugger.create_data_summary(&data);

        assert_eq!(summary.shape, vec![10, 5]);
        assert_eq!(summary.data_type, "Array2<Float>");
        assert!(summary.statistics.is_some());
    }

    #[test]
    fn test_performance_measurement() {
        let mut profiler = PerformanceProfiler::new(ProfilerConfig::default());

        let measurement = PerformanceMeasurement {
            component: "test".to_string(),
            execution_time: Duration::from_millis(100),
            cpu_usage: 50.0,
            memory_usage: MemoryUsage {
                component_memory: 1024,
                heap_memory: 2048,
                peak_memory: 3072,
                allocations: 10,
                deallocations: 8,
            },
            io_operations: IoStatistics {
                bytes_read: 1024,
                bytes_written: 512,
                read_operations: 5,
                write_operations: 3,
                read_latency: Duration::from_millis(1),
                write_latency: Duration::from_millis(2),
            },
            custom_metrics: HashMap::new(),
        };

        profiler.record_measurement(measurement);
        assert_eq!(profiler.measurements.len(), 1);
    }

    #[test]
    fn test_error_tracking() {
        let mut tracker = ErrorTracker::new();

        let error = StepError {
            error_type: "TestError".to_string(),
            message: "Test error message".to_string(),
            stack_trace: None,
            context: HashMap::new(),
            suggested_fixes: vec!["Fix suggestion".to_string()],
        };

        tracker.record_error("test_component", error);
        assert_eq!(tracker.errors.len(), 1);
        assert_eq!(tracker.statistics.total_errors, 1);
    }

    #[test]
    fn test_interactive_debugger() {
        let mut debugger = InteractiveDebugger::new(DebugConfig::default());

        let result = debugger.process_command("help");
        assert!(result.is_ok());

        let result = debugger.process_command("breakpoint list");
        assert!(result.is_ok());

        let result = debugger.process_command("trace");
        assert!(result.is_ok());
    }

    #[test]
    fn test_debug_session() {
        let config = DebugConfig::default();
        let mut session = DebugSession::new(config);

        assert!(matches!(session.state, SessionState::Active));

        session.pause();
        assert!(matches!(session.state, SessionState::Paused));

        session.resume();
        assert!(matches!(session.state, SessionState::Active));

        session.complete();
        assert!(matches!(session.state, SessionState::Completed));
    }

    #[test]
    fn test_bottleneck_detection() {
        let mut detector = BottleneckDetector::new();

        let measurement = PerformanceMeasurement {
            component: "slow_component".to_string(),
            execution_time: Duration::from_secs(20), // Above threshold
            cpu_usage: 90.0,                         // Above threshold
            memory_usage: MemoryUsage {
                component_memory: 2 * 1024 * 1024 * 1024, // 2GB, above threshold
                heap_memory: 4 * 1024 * 1024 * 1024,
                peak_memory: 5 * 1024 * 1024 * 1024,
                allocations: 1000,
                deallocations: 800,
            },
            io_operations: IoStatistics {
                bytes_read: 1024 * 1024,
                bytes_written: 512 * 1024,
                read_operations: 100,
                write_operations: 50,
                read_latency: Duration::from_millis(200), // Above threshold
                write_latency: Duration::from_millis(300),
            },
            custom_metrics: HashMap::new(),
        };

        detector.analyze_measurement(&measurement);
        let bottlenecks = detector.get_bottlenecks();

        // Should detect multiple bottlenecks
        assert!(bottlenecks.len() > 0);
    }

    #[test]
    fn test_report_generation() {
        let debugger = PipelineDebugger::new(DebugConfig::default());

        let console_report = debugger.generate_console_report();
        assert!(console_report.is_ok());

        let json_report = debugger.generate_json_report();
        assert!(json_report.is_ok());

        let html_report = debugger.generate_html_report();
        assert!(html_report.is_ok());

        let graphviz_report = debugger.generate_graphviz_report();
        assert!(graphviz_report.is_ok());
    }
}