sklears_compose/

advanced_debugging.rs

//! Advanced Debugging Utilities for Pipeline Inspection
//!
//! This module provides sophisticated debugging tools for machine learning pipelines,
//! including step-by-step execution, interactive debugging sessions, advanced profiling,
//! and comprehensive pipeline state inspection capabilities.

use sklears_core::{error::Result as SklResult, prelude::SklearsError};
use std::collections::{HashMap, VecDeque};
use std::fmt;
use std::sync::{Arc, Mutex, RwLock};
use std::time::{Duration, Instant, SystemTime};

/// Advanced pipeline debugger with interactive capabilities
pub struct AdvancedPipelineDebugger {
    sessions: Arc<RwLock<HashMap<String, DebugSession>>>,
    global_config: DebugConfig,
    event_log: Arc<Mutex<VecDeque<DebugEvent>>>,
    profiler: Arc<Mutex<AdvancedProfiler>>,
}

impl AdvancedPipelineDebugger {
    #[must_use]
    pub fn new(config: DebugConfig) -> Self {
        Self {
            sessions: Arc::new(RwLock::new(HashMap::new())),
            global_config: config,
            event_log: Arc::new(Mutex::new(VecDeque::new())),
            profiler: Arc::new(Mutex::new(AdvancedProfiler::new())),
        }
    }

    /// Start a new debugging session
    pub fn start_session(
        &self,
        session_id: String,
        pipeline_id: String,
    ) -> SklResult<DebugSessionHandle> {
        let session =
            DebugSession::new(session_id.clone(), pipeline_id, self.global_config.clone());

        {
            let mut sessions = self.sessions.write().unwrap_or_else(|e| e.into_inner());
            sessions.insert(session_id.clone(), session);
        }

        self.log_event(DebugEvent::SessionStarted {
            session_id: session_id.clone(),
            timestamp: SystemTime::now(),
        })?;

        Ok(DebugSessionHandle {
            session_id,
            debugger: self.clone(),
        })
    }

    /// Get session handle for existing session
    #[must_use]
    pub fn get_session(&self, session_id: &str) -> Option<DebugSessionHandle> {
        let sessions = self.sessions.read().unwrap_or_else(|e| e.into_inner());
        if sessions.contains_key(session_id) {
            Some(DebugSessionHandle {
                session_id: session_id.to_string(),
                debugger: self.clone(),
            })
        } else {
            None
        }
    }

    /// List all active sessions
    #[must_use]
    pub fn list_sessions(&self) -> Vec<String> {
        let sessions = self.sessions.read().unwrap_or_else(|e| e.into_inner());
        sessions.keys().cloned().collect()
    }

    /// Get debugging statistics
    #[must_use]
    pub fn get_debug_statistics(&self) -> DebugStatistics {
        let sessions = self.sessions.read().unwrap_or_else(|e| e.into_inner());
        let profiler = self.profiler.lock().unwrap_or_else(|e| e.into_inner());

        /// DebugStatistics
        DebugStatistics {
            active_sessions: sessions.len(),
            total_events: self
                .event_log
                .lock()
                .unwrap_or_else(|e| e.into_inner())
                .len(),
            memory_usage: profiler.get_memory_usage(),
            cpu_usage: profiler.get_cpu_usage(),
            uptime: profiler.get_uptime(),
        }
    }

    fn log_event(&self, event: DebugEvent) -> SklResult<()> {
        let mut log = self.event_log.lock().unwrap_or_else(|e| e.into_inner());
        log.push_back(event);

        // Keep only last N events to prevent memory bloat
        while log.len() > self.global_config.max_event_history {
            log.pop_front();
        }

        Ok(())
    }
}

impl Clone for AdvancedPipelineDebugger {
    fn clone(&self) -> Self {
        Self {
            sessions: Arc::clone(&self.sessions),
            global_config: self.global_config.clone(),
            event_log: Arc::clone(&self.event_log),
            profiler: Arc::clone(&self.profiler),
        }
    }
}

/// Debug session configuration
#[derive(Debug, Clone)]
pub struct DebugConfig {
    pub enable_step_by_step: bool,
    pub enable_breakpoints: bool,
    pub enable_profiling: bool,
    pub enable_memory_tracking: bool,
    pub max_event_history: usize,
    pub auto_save_state: bool,
    pub verbose_logging: bool,
}

impl Default for DebugConfig {
    fn default() -> Self {
        Self {
            enable_step_by_step: true,
            enable_breakpoints: true,
            enable_profiling: true,
            enable_memory_tracking: true,
            max_event_history: 10000,
            auto_save_state: true,
            verbose_logging: false,
        }
    }
}

/// Individual debugging session
pub struct DebugSession {
    pub id: String,
    pub pipeline_id: String,
    pub config: DebugConfig,
    pub state: DebugSessionState,
    pub breakpoints: Vec<Breakpoint>,
    pub watch_expressions: Vec<WatchExpression>,
    pub execution_history: Vec<ExecutionStep>,
    pub current_step: usize,
    pub variable_inspector: VariableInspector,
    pub call_stack: Vec<CallStackFrame>,
}

impl DebugSession {
    #[must_use]
    pub fn new(id: String, pipeline_id: String, config: DebugConfig) -> Self {
        Self {
            id,
            pipeline_id,
            config,
            state: DebugSessionState::Ready,
            breakpoints: Vec::new(),
            watch_expressions: Vec::new(),
            execution_history: Vec::new(),
            current_step: 0,
            variable_inspector: VariableInspector::new(),
            call_stack: Vec::new(),
        }
    }

    /// Add a breakpoint to the session
    pub fn add_breakpoint(&mut self, breakpoint: Breakpoint) {
        self.breakpoints.push(breakpoint);
    }

    /// Add a watch expression
    pub fn add_watch_expression(&mut self, expression: WatchExpression) {
        self.watch_expressions.push(expression);
    }

    /// Step through execution
    pub fn step_next(&mut self) -> SklResult<StepResult> {
        if self.current_step < self.execution_history.len() {
            let step = &self.execution_history[self.current_step];
            self.current_step += 1;

            // Check breakpoints
            if self.should_break_at_step(step) {
                self.state = DebugSessionState::Paused;
                return Ok(StepResult::BreakpointHit(step.clone()));
            }

            self.state = DebugSessionState::Stepping;
            Ok(StepResult::Completed(step.clone()))
        } else {
            self.state = DebugSessionState::Finished;
            Ok(StepResult::ExecutionComplete)
        }
    }

    /// Continue execution until next breakpoint
    pub fn continue_execution(&mut self) -> SklResult<StepResult> {
        self.state = DebugSessionState::Running;

        while self.current_step < self.execution_history.len() {
            let step = &self.execution_history[self.current_step];
            self.current_step += 1;

            if self.should_break_at_step(step) {
                self.state = DebugSessionState::Paused;
                return Ok(StepResult::BreakpointHit(step.clone()));
            }
        }

        self.state = DebugSessionState::Finished;
        Ok(StepResult::ExecutionComplete)
    }

    /// Evaluate watch expressions at current state
    #[must_use]
    pub fn evaluate_watch_expressions(&self) -> Vec<WatchResult> {
        self.watch_expressions
            .iter()
            .map(|expr| self.evaluate_expression(expr))
            .collect()
    }

    /// Get current variable values
    #[must_use]
    pub fn get_variable_values(&self) -> HashMap<String, VariableValue> {
        self.variable_inspector.get_all_variables()
    }

    /// Get current call stack
    #[must_use]
    pub fn get_call_stack(&self) -> &[CallStackFrame] {
        &self.call_stack
    }

    fn should_break_at_step(&self, step: &ExecutionStep) -> bool {
        self.breakpoints.iter().any(|bp| bp.matches_step(step))
    }

    fn evaluate_expression(&self, expression: &WatchExpression) -> WatchResult {
        // Simplified expression evaluation - would be more sophisticated in practice
        /// WatchResult
        WatchResult {
            expression: expression.clone(),
            value: format!("Evaluated: {}", expression.expression),
            error: None,
            timestamp: SystemTime::now(),
        }
    }
}

/// Handle for interacting with a debug session
pub struct DebugSessionHandle {
    session_id: String,
    debugger: AdvancedPipelineDebugger,
}

impl DebugSessionHandle {
    /// Add breakpoint to this session
    pub fn add_breakpoint(&self, breakpoint: Breakpoint) -> SklResult<()> {
        let mut sessions = self
            .debugger
            .sessions
            .write()
            .unwrap_or_else(|e| e.into_inner());
        if let Some(session) = sessions.get_mut(&self.session_id) {
            session.add_breakpoint(breakpoint);
            Ok(())
        } else {
            Err(SklearsError::InvalidState("Session not found".to_string()))
        }
    }

    /// Step to next execution point
    pub fn step_next(&self) -> SklResult<StepResult> {
        let mut sessions = self
            .debugger
            .sessions
            .write()
            .unwrap_or_else(|e| e.into_inner());
        if let Some(session) = sessions.get_mut(&self.session_id) {
            session.step_next()
        } else {
            Err(SklearsError::InvalidState("Session not found".to_string()))
        }
    }

    /// Continue execution
    pub fn continue_execution(&self) -> SklResult<StepResult> {
        let mut sessions = self
            .debugger
            .sessions
            .write()
            .unwrap_or_else(|e| e.into_inner());
        if let Some(session) = sessions.get_mut(&self.session_id) {
            session.continue_execution()
        } else {
            Err(SklearsError::InvalidState("Session not found".to_string()))
        }
    }

    /// Get session state
    #[must_use]
    pub fn get_state(&self) -> Option<DebugSessionState> {
        let sessions = self
            .debugger
            .sessions
            .read()
            .unwrap_or_else(|e| e.into_inner());
        sessions.get(&self.session_id).map(|s| s.state.clone())
    }

    /// Get execution history
    #[must_use]
    pub fn get_execution_history(&self) -> Vec<ExecutionStep> {
        let sessions = self
            .debugger
            .sessions
            .read()
            .unwrap_or_else(|e| e.into_inner());
        sessions
            .get(&self.session_id)
            .map(|s| s.execution_history.clone())
            .unwrap_or_default()
    }
}

/// Debug session state
#[derive(Debug, Clone, PartialEq)]
pub enum DebugSessionState {
    /// Ready
    Ready,
    /// Running
    Running,
    /// Stepping
    Stepping,
    /// Paused
    Paused,
    /// Finished
    Finished,
    /// Error
    Error(String),
}

/// Execution step in debugging
#[derive(Debug, Clone)]
pub struct ExecutionStep {
    pub step_id: String,
    pub component: String,
    pub operation: String,
    pub input_shape: Option<(usize, usize)>,
    pub output_shape: Option<(usize, usize)>,
    pub duration: Duration,
    pub memory_delta: i64,
    pub timestamp: SystemTime,
    pub metadata: HashMap<String, String>,
}

/// Breakpoint definition
#[derive(Debug, Clone)]
pub struct Breakpoint {
    pub id: String,
    pub condition: BreakpointCondition,
    pub enabled: bool,
    pub hit_count: usize,
    pub hit_limit: Option<usize>,
}

impl Breakpoint {
    #[must_use]
    pub fn new(id: String, condition: BreakpointCondition) -> Self {
        Self {
            id,
            condition,
            enabled: true,
            hit_count: 0,
            hit_limit: None,
        }
    }

    #[must_use]
    pub fn matches_step(&self, step: &ExecutionStep) -> bool {
        if !self.enabled {
            return false;
        }

        if let Some(limit) = self.hit_limit {
            if self.hit_count >= limit {
                return false;
            }
        }

        self.condition.matches(step)
    }
}

/// Breakpoint condition types
#[derive(Debug, Clone)]
pub enum BreakpointCondition {
    /// ComponentName
    ComponentName(String),
    /// OperationType
    OperationType(String),
    /// StepId
    StepId(String),
    /// MemoryThreshold
    MemoryThreshold(i64),
    /// DurationThreshold
    DurationThreshold(Duration),
    /// Custom
    Custom(String), // Custom expression
}

impl BreakpointCondition {
    #[must_use]
    pub fn matches(&self, step: &ExecutionStep) -> bool {
        match self {
            BreakpointCondition::ComponentName(name) => step.component.contains(name),
            BreakpointCondition::OperationType(op) => step.operation.contains(op),
            BreakpointCondition::StepId(id) => step.step_id == *id,
            BreakpointCondition::MemoryThreshold(threshold) => {
                step.memory_delta.abs() >= *threshold
            }
            BreakpointCondition::DurationThreshold(threshold) => step.duration >= *threshold,
            BreakpointCondition::Custom(_expr) => {
                // Would evaluate custom expression against step
                false
            }
        }
    }
}

/// Watch expression for monitoring variables
#[derive(Debug, Clone)]
pub struct WatchExpression {
    pub id: String,
    pub expression: String,
    pub description: String,
    pub enabled: bool,
}

/// Result of evaluating a watch expression
#[derive(Debug, Clone)]
pub struct WatchResult {
    pub expression: WatchExpression,
    pub value: String,
    pub error: Option<String>,
    pub timestamp: SystemTime,
}

/// Step execution result
#[derive(Debug, Clone)]
pub enum StepResult {
    /// Completed
    Completed(ExecutionStep),
    /// BreakpointHit
    BreakpointHit(ExecutionStep),
    /// ExecutionComplete
    ExecutionComplete,
    /// Error
    Error(String),
}

/// Variable inspector for tracking pipeline state
pub struct VariableInspector {
    variables: HashMap<String, VariableValue>,
    history: VecDeque<VariableSnapshot>,
}

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

impl VariableInspector {
    #[must_use]
    pub fn new() -> Self {
        Self {
            variables: HashMap::new(),
            history: VecDeque::new(),
        }
    }

    pub fn set_variable(&mut self, name: String, value: VariableValue) {
        self.variables.insert(name, value);
    }

    #[must_use]
    pub fn get_variable(&self, name: &str) -> Option<&VariableValue> {
        self.variables.get(name)
    }

    #[must_use]
    pub fn get_all_variables(&self) -> HashMap<String, VariableValue> {
        self.variables.clone()
    }

    pub fn take_snapshot(&mut self) -> String {
        let snapshot = VariableSnapshot {
            timestamp: SystemTime::now(),
            variables: self.variables.clone(),
        };

        let snapshot_id = format!("snapshot_{}", self.history.len());
        self.history.push_back(snapshot);

        // Keep only last 100 snapshots
        while self.history.len() > 100 {
            self.history.pop_front();
        }

        snapshot_id
    }
}

/// Variable value representation
#[derive(Debug, Clone)]
pub enum VariableValue {
    /// Scalar
    Scalar(f64),
    /// Array1D
    Array1D(Vec<f64>),
    /// Array2D
    Array2D {
        shape: (usize, usize),
        data: Vec<f64>,
    },
    /// String
    String(String),
    /// Boolean
    Boolean(bool),
    /// Object
    Object(String), // Serialized representation
}

impl fmt::Display for VariableValue {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            VariableValue::Scalar(v) => write!(f, "{v}"),
            VariableValue::Array1D(v) => write!(f, "Array1D[{}]", v.len()),
            VariableValue::Array2D { shape, .. } => write!(f, "Array2D[{}x{}]", shape.0, shape.1),
            VariableValue::String(s) => write!(f, "\"{s}\""),
            VariableValue::Boolean(b) => write!(f, "{b}"),
            VariableValue::Object(repr) => write!(f, "{repr}"),
        }
    }
}

/// Variable state snapshot
#[derive(Debug, Clone)]
struct VariableSnapshot {
    timestamp: SystemTime,
    variables: HashMap<String, VariableValue>,
}

/// Call stack frame
#[derive(Debug, Clone)]
pub struct CallStackFrame {
    pub function_name: String,
    pub component: String,
    pub file: Option<String>,
    pub line: Option<usize>,
    pub local_variables: HashMap<String, VariableValue>,
}

/// Debug event for logging
#[derive(Debug, Clone)]
pub enum DebugEvent {
    /// SessionStarted
    SessionStarted {
        session_id: String,
        timestamp: SystemTime,
    },
    /// SessionEnded
    SessionEnded {
        session_id: String,
        timestamp: SystemTime,
    },
    /// BreakpointHit
    BreakpointHit {
        session_id: String,
        breakpoint_id: String,
        step: ExecutionStep,
    },
    /// StepExecuted
    StepExecuted {
        session_id: String,
        step: ExecutionStep,
    },
    /// Error
    Error {
        session_id: String,
        error: String,
        timestamp: SystemTime,
    },
}

/// Advanced profiler for debugging
pub struct AdvancedProfiler {
    start_time: Instant,
    memory_samples: VecDeque<MemorySample>,
    cpu_samples: VecDeque<CpuSample>,
}

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

impl AdvancedProfiler {
    #[must_use]
    pub fn new() -> Self {
        Self {
            start_time: Instant::now(),
            memory_samples: VecDeque::new(),
            cpu_samples: VecDeque::new(),
        }
    }

    pub fn sample_memory(&mut self) {
        let sample = MemorySample {
            timestamp: Instant::now(),
            used_bytes: Self::get_current_memory_usage(),
            peak_bytes: Self::get_peak_memory_usage(),
        };

        self.memory_samples.push_back(sample);

        // Keep only last hour of samples (assuming 1 sample per second)
        while self.memory_samples.len() > 3600 {
            self.memory_samples.pop_front();
        }
    }

    #[must_use]
    pub fn get_memory_usage(&self) -> usize {
        Self::get_current_memory_usage()
    }

    #[must_use]
    pub fn get_cpu_usage(&self) -> f64 {
        // Simplified CPU usage - would use system APIs in practice
        0.0
    }

    #[must_use]
    pub fn get_uptime(&self) -> Duration {
        self.start_time.elapsed()
    }

    fn get_current_memory_usage() -> usize {
        // Simplified - would use actual memory measurement
        0
    }

    fn get_peak_memory_usage() -> usize {
        // Simplified - would track actual peak usage
        0
    }
}

/// Memory usage sample
#[derive(Debug, Clone)]
pub struct MemorySample {
    pub timestamp: Instant,
    pub used_bytes: usize,
    pub peak_bytes: usize,
}

/// CPU usage sample
#[derive(Debug, Clone)]
pub struct CpuSample {
    pub timestamp: Instant,
    pub usage_percent: f64,
}

/// Debug statistics
#[derive(Debug, Clone)]
pub struct DebugStatistics {
    pub active_sessions: usize,
    pub total_events: usize,
    pub memory_usage: usize,
    pub cpu_usage: f64,
    pub uptime: Duration,
}

/// Interactive debugging utilities
pub mod interactive {
    use super::{
        AdvancedPipelineDebugger, Breakpoint, BreakpointCondition, DebugSessionState, Duration,
        ExecutionStep, HashMap, SklResult, SklearsError, StepResult, SystemTime, VecDeque,
    };

    /// Interactive debug console
    pub struct DebugConsole {
        debugger: AdvancedPipelineDebugger,
        current_session: Option<String>,
        command_history: VecDeque<String>,
    }

    impl DebugConsole {
        #[must_use]
        pub fn new(debugger: AdvancedPipelineDebugger) -> Self {
            Self {
                debugger,
                current_session: None,
                command_history: VecDeque::new(),
            }
        }

        /// Execute debug command
        pub fn execute_command(&mut self, command: &str) -> SklResult<String> {
            self.command_history.push_back(command.to_string());

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

            match parts[0] {
                "help" => Ok(self.show_help()),
                "sessions" => Ok(self.list_sessions()),
                "use" => self.use_session(parts.get(1).copied()),
                "breakpoint" => self.add_breakpoint(&parts[1..]),
                "watch" => self.add_watch(&parts[1..]),
                "step" => self.step_execution(),
                "continue" => self.continue_execution(),
                "vars" => self.show_variables(),
                "stack" => self.show_call_stack(),
                "stats" => Ok(self.show_statistics()),
                "visualize" => self.visualize_pipeline(),
                "replay" => self.replay_execution(),
                "profile" => self.show_profiling_data(),
                "timeline" => self.show_execution_timeline(),
                _ => Ok(format!("Unknown command: {}", parts[0])),
            }
        }

        fn show_help(&self) -> String {
            r"Available commands:
  help                    - Show this help message
  sessions               - List all debug sessions
  use <session_id>       - Switch to a session
  breakpoint <condition> - Add a breakpoint
  watch <expression>     - Add a watch expression
  step                   - Step to next execution point
  continue               - Continue execution
  vars                   - Show current variables
  stack                  - Show call stack
  stats                  - Show debug statistics
  visualize              - Visualize current pipeline structure
  replay                 - Replay pipeline execution
  profile                - Show profiling data
  timeline               - Show execution timeline"
                .to_string()
        }

        fn list_sessions(&self) -> String {
            let sessions = self.debugger.list_sessions();
            if sessions.is_empty() {
                "No active sessions".to_string()
            } else {
                format!("Active sessions: {}", sessions.join(", "))
            }
        }

        fn use_session(&mut self, session_id: Option<&str>) -> SklResult<String> {
            match session_id {
                Some(id) => {
                    if self.debugger.get_session(id).is_some() {
                        self.current_session = Some(id.to_string());
                        Ok(format!("Switched to session: {id}"))
                    } else {
                        Ok(format!("Session not found: {id}"))
                    }
                }
                None => Ok("Usage: use <session_id>".to_string()),
            }
        }

        fn add_breakpoint(&self, args: &[&str]) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                if let Some(handle) = self.debugger.get_session(session_id) {
                    let condition = if args.is_empty() {
                        BreakpointCondition::ComponentName("*".to_string())
                    } else {
                        BreakpointCondition::ComponentName(args.join(" "))
                    };

                    let breakpoint = Breakpoint::new(
                        format!("bp_{}", chrono::Utc::now().timestamp()),
                        condition,
                    );

                    handle.add_breakpoint(breakpoint)?;
                    Ok("Breakpoint added".to_string())
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session. Use 'use <session_id>' first.".to_string())
            }
        }

        fn add_watch(&self, args: &[&str]) -> SklResult<String> {
            if args.is_empty() {
                return Ok("Usage: watch <expression>".to_string());
            }

            // Watch expression logic would be implemented here
            Ok(format!("Watch added: {}", args.join(" ")))
        }

        fn step_execution(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                if let Some(handle) = self.debugger.get_session(session_id) {
                    match handle.step_next()? {
                        StepResult::Completed(step) => {
                            Ok(format!("Stepped: {} -> {}", step.component, step.operation))
                        }
                        StepResult::BreakpointHit(step) => Ok(format!(
                            "Breakpoint hit at: {} -> {}",
                            step.component, step.operation
                        )),
                        StepResult::ExecutionComplete => Ok("Execution completed".to_string()),
                        StepResult::Error(err) => Ok(format!("Error: {err}")),
                    }
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }

        fn continue_execution(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                if let Some(handle) = self.debugger.get_session(session_id) {
                    match handle.continue_execution()? {
                        StepResult::BreakpointHit(step) => Ok(format!(
                            "Breakpoint hit at: {} -> {}",
                            step.component, step.operation
                        )),
                        StepResult::ExecutionComplete => Ok("Execution completed".to_string()),
                        StepResult::Error(err) => Ok(format!("Error: {err}")),
                        _ => Ok("Continued execution".to_string()),
                    }
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }

        fn show_variables(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                let sessions = self
                    .debugger
                    .sessions
                    .read()
                    .unwrap_or_else(|e| e.into_inner());
                if let Some(session) = sessions.get(session_id) {
                    let variables = session.get_variable_values();
                    if variables.is_empty() {
                        Ok("No variables in current scope".to_string())
                    } else {
                        let mut output = String::from("Variables:\n");
                        for (name, value) in variables {
                            output.push_str(&format!("  {name} = {value}\n"));
                        }
                        Ok(output)
                    }
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }

        fn show_call_stack(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                let sessions = self
                    .debugger
                    .sessions
                    .read()
                    .unwrap_or_else(|e| e.into_inner());
                if let Some(session) = sessions.get(session_id) {
                    let stack = session.get_call_stack();
                    if stack.is_empty() {
                        Ok("Empty call stack".to_string())
                    } else {
                        let mut output = String::from("Call Stack:\n");
                        for (i, frame) in stack.iter().enumerate() {
                            output.push_str(&format!(
                                "  #{}: {} in {} ({}:{})\n",
                                i,
                                frame.function_name,
                                frame.component,
                                frame.file.as_ref().unwrap_or(&"unknown".to_string()),
                                frame.line.unwrap_or(0)
                            ));
                        }
                        Ok(output)
                    }
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }

        fn show_statistics(&self) -> String {
            let stats = self.debugger.get_debug_statistics();
            format!(
                "Statistics:\n  Active sessions: {}\n  Total events: {}\n  Memory usage: {} bytes\n  CPU usage: {:.1}%\n  Uptime: {:.2}s",
                stats.active_sessions,
                stats.total_events,
                stats.memory_usage,
                stats.cpu_usage,
                stats.uptime.as_secs_f64()
            )
        }

        /// Visualize the current pipeline structure
        fn visualize_pipeline(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                let sessions = self
                    .debugger
                    .sessions
                    .read()
                    .unwrap_or_else(|e| e.into_inner());
                if let Some(session) = sessions.get(session_id) {
                    let mut visualization = String::from("Pipeline Visualization:\n");

                    // Simple ASCII art representation of pipeline
                    if session.execution_history.is_empty() {
                        visualization.push_str("  No execution history available\n");
                    } else {
                        visualization.push_str("  ┌─ Start\n");
                        for (i, step) in session.execution_history.iter().enumerate() {
                            let marker = if i == session.current_step.saturating_sub(1) {
                                "►"
                            } else {
                                " "
                            };

                            visualization.push_str(&format!(
                                "  │{} Step {}: {} -> {}\n",
                                marker,
                                i + 1,
                                step.component,
                                step.operation
                            ));
                        }
                        visualization.push_str("  └─ End\n");
                    }

                    Ok(visualization)
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }

        /// Replay pipeline execution from the beginning
        fn replay_execution(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                let mut sessions = self
                    .debugger
                    .sessions
                    .write()
                    .unwrap_or_else(|e| e.into_inner());
                if let Some(session) = sessions.get_mut(session_id) {
                    session.current_step = 0;
                    session.state = DebugSessionState::Ready;
                    Ok(
                        "Execution replay started. Use 'step' or 'continue' to proceed."
                            .to_string(),
                    )
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }

        /// Show profiling data for the current session
        fn show_profiling_data(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                let sessions = self
                    .debugger
                    .sessions
                    .read()
                    .unwrap_or_else(|e| e.into_inner());
                if let Some(session) = sessions.get(session_id) {
                    let mut output = String::from("Profiling Data:\n");

                    if session.execution_history.is_empty() {
                        output.push_str("  No profiling data available\n");
                        return Ok(output);
                    }

                    // Calculate statistics
                    let total_duration: Duration = session
                        .execution_history
                        .iter()
                        .map(|step| step.duration)
                        .sum();

                    let total_memory_delta: i64 = session
                        .execution_history
                        .iter()
                        .map(|step| step.memory_delta)
                        .sum();

                    output.push_str(&format!(
                        "  Total Duration: {:.2}ms\n",
                        total_duration.as_millis()
                    ));
                    output.push_str(&format!(
                        "  Total Memory Delta: {total_memory_delta} bytes\n"
                    ));
                    output.push_str(&format!(
                        "  Average Step Duration: {:.2}ms\n",
                        total_duration.as_millis() as f64 / session.execution_history.len() as f64
                    ));

                    // Show top 5 slowest steps
                    let mut sorted_steps = session.execution_history.clone();
                    sorted_steps.sort_by(|a, b| b.duration.cmp(&a.duration));

                    output.push_str("\n  Slowest Steps:\n");
                    for (i, step) in sorted_steps.iter().take(5).enumerate() {
                        output.push_str(&format!(
                            "    {}. {} -> {} ({:.2}ms)\n",
                            i + 1,
                            step.component,
                            step.operation,
                            step.duration.as_millis()
                        ));
                    }

                    Ok(output)
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }

        /// Show execution timeline
        fn show_execution_timeline(&self) -> SklResult<String> {
            if let Some(session_id) = &self.current_session {
                let sessions = self
                    .debugger
                    .sessions
                    .read()
                    .unwrap_or_else(|e| e.into_inner());
                if let Some(session) = sessions.get(session_id) {
                    let mut output = String::from("Execution Timeline:\n");

                    if session.execution_history.is_empty() {
                        output.push_str("  No execution history available\n");
                        return Ok(output);
                    }

                    // Create a simple timeline visualization
                    let start_time = session
                        .execution_history
                        .first()
                        .map(|s| s.timestamp)
                        .unwrap_or_else(std::time::SystemTime::now);

                    for (i, step) in session.execution_history.iter().enumerate() {
                        let elapsed = step
                            .timestamp
                            .duration_since(start_time)
                            .unwrap_or(Duration::ZERO);

                        let marker = if i == session.current_step.saturating_sub(1) {
                            "►"
                        } else {
                            "•"
                        };

                        output.push_str(&format!(
                            "  {:>8.2}ms {} {} -> {} ({:.1}ms, {} bytes)\n",
                            elapsed.as_millis(),
                            marker,
                            step.component,
                            step.operation,
                            step.duration.as_millis(),
                            step.memory_delta
                        ));
                    }

                    Ok(output)
                } else {
                    Ok("Session not found".to_string())
                }
            } else {
                Ok("No active session".to_string())
            }
        }
    }

    /// Enhanced breakpoint conditions with advanced pattern matching
    pub struct AdvancedBreakpointCondition {
        pub condition_type: AdvancedConditionType,
        pub parameters: HashMap<String, String>,
    }

    #[derive(Debug, Clone)]
    pub enum AdvancedConditionType {
        /// Break when memory usage exceeds threshold
        MemoryThreshold { threshold_mb: f64 },
        /// Break when execution time exceeds threshold
        DurationThreshold { threshold_ms: f64 },
        /// Break on specific data shape
        DataShape { expected_shape: (usize, usize) },
        /// Break on specific value patterns
        ValuePattern { pattern: String },
        /// Break on error conditions
        ErrorCondition { error_type: String },
        /// Break on performance degradation
        PerformanceDegradation { baseline_ratio: f64 },
        /// Custom breakpoint with user-defined logic
        Custom { expression: String },
    }

    impl AdvancedBreakpointCondition {
        #[must_use]
        pub fn matches(&self, step: &ExecutionStep) -> bool {
            match &self.condition_type {
                AdvancedConditionType::MemoryThreshold { threshold_mb } => {
                    (step.memory_delta.abs() as f64 / 1024.0 / 1024.0) >= *threshold_mb
                }
                AdvancedConditionType::DurationThreshold { threshold_ms } => {
                    step.duration.as_millis() as f64 >= *threshold_ms
                }
                AdvancedConditionType::DataShape { expected_shape } => {
                    step.input_shape == Some(*expected_shape)
                        || step.output_shape == Some(*expected_shape)
                }
                AdvancedConditionType::ValuePattern { pattern } => {
                    step.metadata.values().any(|v| v.contains(pattern))
                }
                AdvancedConditionType::ErrorCondition { error_type } => {
                    step.metadata.get("error_type") == Some(error_type)
                }
                AdvancedConditionType::PerformanceDegradation { baseline_ratio } => {
                    // Would compare against baseline performance
                    false // Placeholder
                }
                AdvancedConditionType::Custom {
                    expression: _expression,
                } => {
                    // Would evaluate custom expression
                    false // Placeholder
                }
            }
        }
    }

    /// Pipeline replay manager for advanced debugging
    pub struct PipelineReplayManager {
        recorded_executions: HashMap<String, Vec<ExecutionStep>>,
        current_replay: Option<String>,
        replay_position: usize,
    }

    impl PipelineReplayManager {
        #[must_use]
        pub fn new() -> Self {
            Self {
                recorded_executions: HashMap::new(),
                current_replay: None,
                replay_position: 0,
            }
        }

        /// Record an execution for later replay
        pub fn record_execution(&mut self, pipeline_id: String, steps: Vec<ExecutionStep>) {
            self.recorded_executions.insert(pipeline_id, steps);
        }

        /// Start replaying a recorded execution
        pub fn start_replay(&mut self, pipeline_id: &str) -> SklResult<()> {
            if self.recorded_executions.contains_key(pipeline_id) {
                self.current_replay = Some(pipeline_id.to_string());
                self.replay_position = 0;
                Ok(())
            } else {
                Err(SklearsError::InvalidState(format!(
                    "No recording found for pipeline: {pipeline_id}"
                )))
            }
        }

        /// Get next step in replay
        pub fn next_replay_step(&mut self) -> Option<&ExecutionStep> {
            if let Some(pipeline_id) = &self.current_replay {
                if let Some(steps) = self.recorded_executions.get(pipeline_id) {
                    if self.replay_position < steps.len() {
                        let step = &steps[self.replay_position];
                        self.replay_position += 1;
                        return Some(step);
                    }
                }
            }
            None
        }

        /// Skip to specific position in replay
        pub fn seek_replay(&mut self, position: usize) -> SklResult<()> {
            if let Some(pipeline_id) = &self.current_replay {
                if let Some(steps) = self.recorded_executions.get(pipeline_id) {
                    if position < steps.len() {
                        self.replay_position = position;
                        return Ok(());
                    }
                }
            }
            Err(SklearsError::InvalidState(
                "Invalid replay position".to_string(),
            ))
        }

        /// Get replay statistics
        #[must_use]
        pub fn get_replay_stats(&self) -> Option<ReplayStatistics> {
            if let Some(pipeline_id) = &self.current_replay {
                if let Some(steps) = self.recorded_executions.get(pipeline_id) {
                    return Some(ReplayStatistics {
                        total_steps: steps.len(),
                        current_position: self.replay_position,
                        total_duration: steps.iter().map(|s| s.duration).sum(),
                        total_memory_usage: steps.iter().map(|s| s.memory_delta).sum(),
                    });
                }
            }
            None
        }
    }

    /// Statistics for pipeline replay
    #[derive(Debug, Clone)]
    pub struct ReplayStatistics {
        pub total_steps: usize,
        pub current_position: usize,
        pub total_duration: Duration,
        pub total_memory_usage: i64,
    }

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

    /// Performance bottleneck detector
    pub struct BottleneckDetector {
        execution_profiles: HashMap<String, Vec<ExecutionStep>>,
        performance_baselines: HashMap<String, PerformanceBaseline>,
    }

    impl BottleneckDetector {
        #[must_use]
        pub fn new() -> Self {
            Self {
                execution_profiles: HashMap::new(),
                performance_baselines: HashMap::new(),
            }
        }

        /// Add execution profile for analysis
        pub fn add_profile(&mut self, pipeline_id: String, steps: Vec<ExecutionStep>) {
            self.execution_profiles.insert(pipeline_id, steps);
        }

        /// Detect bottlenecks in a pipeline
        #[must_use]
        pub fn detect_bottlenecks(&self, pipeline_id: &str) -> Vec<BottleneckReport> {
            let mut bottlenecks = Vec::new();

            if let Some(steps) = self.execution_profiles.get(pipeline_id) {
                // Detect time bottlenecks
                let total_duration: Duration = steps.iter().map(|s| s.duration).sum();
                let average_duration = total_duration / steps.len() as u32;

                for step in steps {
                    if step.duration > average_duration * 3 {
                        bottlenecks.push(BottleneckReport {
                            bottleneck_type: BottleneckType::Performance,
                            component: step.component.clone(),
                            severity: if step.duration > average_duration * 5 {
                                BottleneckSeverity::Critical
                            } else {
                                BottleneckSeverity::Major
                            },
                            description: format!(
                                "Step duration ({:.2}ms) significantly exceeds average ({:.2}ms)",
                                step.duration.as_millis(),
                                average_duration.as_millis()
                            ),
                            suggested_actions: vec![
                                "Profile individual operations within this component".to_string(),
                                "Consider algorithm optimization".to_string(),
                                "Check for inefficient data structures".to_string(),
                            ],
                        });
                    }
                }

                // Detect memory bottlenecks
                for step in steps {
                    if step.memory_delta.abs() > 100 * 1024 * 1024 {
                        // 100MB threshold
                        bottlenecks.push(BottleneckReport {
                            bottleneck_type: BottleneckType::Memory,
                            component: step.component.clone(),
                            severity: if step.memory_delta.abs() > 500 * 1024 * 1024 {
                                BottleneckSeverity::Critical
                            } else {
                                BottleneckSeverity::Major
                            },
                            description: format!(
                                "Large memory allocation/deallocation: {} MB",
                                step.memory_delta / 1024 / 1024
                            ),
                            suggested_actions: vec![
                                "Review memory allocation patterns".to_string(),
                                "Consider streaming or chunked processing".to_string(),
                                "Implement memory pooling".to_string(),
                            ],
                        });
                    }
                }
            }

            bottlenecks
        }

        /// Set performance baseline for comparison
        pub fn set_baseline(&mut self, pipeline_id: String, baseline: PerformanceBaseline) {
            self.performance_baselines.insert(pipeline_id, baseline);
        }
    }

    /// Bottleneck report
    #[derive(Debug, Clone)]
    pub struct BottleneckReport {
        pub bottleneck_type: BottleneckType,
        pub component: String,
        pub severity: BottleneckSeverity,
        pub description: String,
        pub suggested_actions: Vec<String>,
    }

    /// Types of performance bottlenecks
    #[derive(Debug, Clone, PartialEq)]
    pub enum BottleneckType {
        /// Performance
        Performance,
        /// Memory
        Memory,
        /// IO
        IO,
        /// Synchronization
        Synchronization,
    }

    /// Severity levels for bottlenecks
    #[derive(Debug, Clone, PartialEq, PartialOrd)]
    pub enum BottleneckSeverity {
        /// Minor
        Minor,
        /// Major
        Major,
        /// Critical
        Critical,
    }

    /// Performance baseline for comparison
    #[derive(Debug, Clone)]
    pub struct PerformanceBaseline {
        pub average_duration: Duration,
        pub average_memory_usage: i64,
        pub step_count: usize,
        pub recorded_at: SystemTime,
    }

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

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

    #[test]
    fn test_debug_session_creation() {
        let config = DebugConfig::default();
        let debugger = AdvancedPipelineDebugger::new(config);

        let handle = debugger
            .start_session("test_session".to_string(), "test_pipeline".to_string())
            .expect("operation should succeed");

        assert_eq!(debugger.list_sessions().len(), 1);
        assert!(debugger.get_session("test_session").is_some());
    }

    #[test]
    fn test_breakpoint_creation() {
        let breakpoint = Breakpoint::new(
            "test_bp".to_string(),
            BreakpointCondition::ComponentName("TestComponent".to_string()),
        );

        assert_eq!(breakpoint.id, "test_bp");
        assert!(breakpoint.enabled);
        assert_eq!(breakpoint.hit_count, 0);
    }

    #[test]
    fn test_watch_expression() {
        let watch = WatchExpression {
            id: "test_watch".to_string(),
            expression: "x + y".to_string(),
            description: "Sum of x and y".to_string(),
            enabled: true,
        };

        assert_eq!(watch.expression, "x + y");
        assert!(watch.enabled);
    }

    #[test]
    fn test_variable_inspector() {
        let mut inspector = VariableInspector::new();

        inspector.set_variable("test_var".to_string(), VariableValue::Scalar(42.0));

        let value = inspector
            .get_variable("test_var")
            .expect("operation should succeed");
        match value {
            VariableValue::Scalar(v) => assert_eq!(*v, 42.0),
            _ => panic!("Expected scalar value"),
        }
    }
}