quantrs2-core 0.1.3

//! Advanced Quantum Circuit Debugger with Enhanced SciRS2 Visualization Tools
//!
//! This module provides state-of-the-art quantum circuit debugging capabilities
//! with advanced visualization, interactive debugging, and comprehensive analysis
//! using SciRS2's powerful visualization and analysis tools.

use crate::gate_translation::GateType;
use crate::error::QuantRS2Error;
use crate::quantum_debugger::{QuantumGate, DebugConfig, DebugStep, StateSnapshot};
use scirs2_core::Complex64;
use std::fmt::Write;
// use scirs2_core::parallel_ops::*;
use crate::parallel_ops_stubs::*;
// use scirs2_core::memory::BufferPool;
use crate::buffer_pool::BufferPool;
use scirs2_core::ndarray::{Array2, Array1, ArrayView1};
use std::collections::{HashMap, VecDeque, BTreeMap};
use std::time::{Duration, Instant};
use std::sync::{Arc, Mutex};
use serde::{Serialize, Deserialize};
use std::io::Write as IoWrite;

/// Advanced visualization configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct VisualizationConfig {
    /// Enable real-time visualization
    pub real_time_viz: bool,
    /// Enable 3D state vector visualization
    pub enable_3d_viz: bool,
    /// Enable Bloch sphere visualization
    pub enable_bloch_sphere: bool,
    /// Enable density matrix visualization
    pub enable_density_matrix: bool,
    /// Enable circuit diagram generation
    pub enable_circuit_diagram: bool,
    /// Enable entanglement graph visualization
    pub enable_entanglement_graph: bool,
    /// Visualization output format
    pub output_formats: Vec<OutputFormat>,
    /// Frame rate for animations (fps)
    pub animation_fps: u32,
    /// Color scheme for visualizations
    pub color_scheme: ColorScheme,
}

impl Default for VisualizationConfig {
    fn default() -> Self {
        Self {
            real_time_viz: true,
            enable_3d_viz: true,
            enable_bloch_sphere: true,
            enable_density_matrix: false,
            enable_circuit_diagram: true,
            enable_entanglement_graph: true,
            output_formats: vec![OutputFormat::SVG, OutputFormat::PNG, OutputFormat::HTML],
            animation_fps: 30,
            color_scheme: ColorScheme::default(),
        }
    }
}

/// Output formats for visualizations
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum OutputFormat {
    SVG,
    PNG,
    HTML,
    JSON,
    LaTeX,
    ASCII,
}

/// Color scheme for visualizations
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ColorScheme {
    pub background: String,
    pub foreground: String,
    pub amplitude_positive: String,
    pub amplitude_negative: String,
    pub phase_colors: Vec<String>,
    pub entanglement_gradient: Vec<String>,
}

impl Default for ColorScheme {
    fn default() -> Self {
        Self {
            background: "#FFFFFF".to_string(),
            foreground: "#000000".to_string(),
            amplitude_positive: "#1E88E5".to_string(),
            amplitude_negative: "#E53935".to_string(),
            phase_colors: vec![
                "#FF6B6B".to_string(),
                "#4ECDC4".to_string(),
                "#45B7D1".to_string(),
                "#FFA07A".to_string(),
                "#98D8C8".to_string(),
            ],
            entanglement_gradient: vec![
                "#E3F2FD".to_string(),
                "#1976D2".to_string(),
                "#0D47A1".to_string(),
            ],
        }
    }
}

/// Advanced debugging configuration with SciRS2 enhancements
#[derive(Debug, Clone)]
pub struct AdvancedDebugConfig {
    /// Base configuration
    pub base_config: DebugConfig,
    /// Visualization configuration
    pub viz_config: VisualizationConfig,
    /// Enable interactive debugging
    pub enable_interactive: bool,
    /// Enable step-by-step execution
    pub enable_stepping: bool,
    /// Enable watchpoints
    pub enable_watchpoints: bool,
    /// Maximum history size
    pub max_history_size: usize,
    /// Enable advanced analysis
    pub enable_advanced_analysis: bool,
    /// Analysis depth level (1-5)
    pub analysis_depth: u8,
}

impl Default for AdvancedDebugConfig {
    fn default() -> Self {
        Self {
            base_config: DebugConfig::default(),
            viz_config: VisualizationConfig::default(),
            enable_interactive: true,
            enable_stepping: true,
            enable_watchpoints: true,
            max_history_size: 1000,
            enable_advanced_analysis: true,
            analysis_depth: 3,
        }
    }
}

/// Interactive debugging commands
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum DebugCommand {
    /// Continue execution
    Continue,
    /// Step to next gate
    Step,
    /// Step into gate decomposition
    StepInto,
    /// Step out of current decomposition
    StepOut,
    /// Run to specific step
    RunTo(usize),
    /// Inspect state at current step
    InspectState,
    /// Inspect specific qubit
    InspectQubit(usize),
    /// Show entanglement map
    ShowEntanglement,
    /// Show amplitude distribution
    ShowAmplitudes,
    /// Set watchpoint
    SetWatchpoint(WatchpointType),
    /// Clear watchpoint
    ClearWatchpoint(usize),
    /// Show circuit diagram
    ShowCircuit,
    /// Export visualization
    Export(OutputFormat),
    /// Quit debugging
    Quit,
}

/// Watchpoint types for advanced debugging
#[derive(Debug, Clone, PartialEq)]
pub enum WatchpointType {
    /// Watch amplitude changes on specific qubit
    AmplitudeWatch { qubit: usize, threshold: f64 },
    /// Watch phase changes
    PhaseWatch { qubit: usize, threshold: f64 },
    /// Watch entanglement between qubits
    EntanglementWatch { qubit1: usize, qubit2: usize, threshold: f64 },
    /// Watch fidelity drop
    FidelityWatch { threshold: f64 },
    /// Watch specific state pattern
    StatePatternWatch { pattern: Vec<Complex64>, tolerance: f64 },
}

/// Advanced quantum circuit debugger with SciRS2 visualization
pub struct AdvancedQuantumDebugger {
    config: AdvancedDebugConfig,
    execution_trace: Vec<DebugStep>,
    current_step: usize,
    state_history: VecDeque<StateSnapshot>,
    watchpoints: Vec<(usize, WatchpointType, bool)>, // (id, type, enabled)
    visualizations: HashMap<usize, VisualizationData>,
    interactive_session: Option<InteractiveSession>,
    analysis_cache: HashMap<usize, AnalysisResult>,
    buffer_pool: Arc<BufferPool<Complex64>>,
}

impl AdvancedQuantumDebugger {
    /// Create a new advanced quantum debugger
    pub fn new() -> Self {
        Self::with_config(AdvancedDebugConfig::default())
    }

    /// Create with custom configuration
    pub fn with_config(config: AdvancedDebugConfig) -> Self {
        Self {
            config,
            execution_trace: Vec::new(),
            current_step: 0,
            state_history: VecDeque::new(),
            watchpoints: Vec::new(),
            visualizations: HashMap::new(),
            interactive_session: None,
            analysis_cache: HashMap::new(),
            buffer_pool: Arc::new(BufferPool::new()),
        }
    }

    /// Start interactive debugging session
    pub fn start_interactive_session(
        &mut self,
        circuit: &[QuantumGate],
        initial_state: &[Complex64],
        num_qubits: usize,
    ) -> Result<InteractiveDebugResult, QuantRS2Error> {
        self.interactive_session = Some(InteractiveSession {
            circuit: circuit.to_vec(),
            current_state: initial_state.to_vec(),
            num_qubits,
            is_running: true,
            command_history: Vec::new(),
        });

        // Initial visualization
        if self.config.viz_config.enable_circuit_diagram {
            self.generate_circuit_diagram(circuit, num_qubits)?;
        }

        Ok(InteractiveDebugResult {
            session_id: uuid::Uuid::new_v4().to_string(),
            initial_viz: self.create_initial_visualization(initial_state, num_qubits)?,
        })
    }

    /// Process debug command
    pub fn process_command(&mut self, command: DebugCommand) -> Result<CommandResult, QuantRS2Error> {
        let session = self.interactive_session.as_mut()
            .ok_or_else(|| QuantRS2Error::InvalidOperation("No active debugging session".into()))?;

        match command {
            DebugCommand::Continue => self.continue_execution(session),
            DebugCommand::Step => self.step_execution(session),
            DebugCommand::StepInto => self.step_into(session),
            DebugCommand::StepOut => self.step_out(session),
            DebugCommand::RunTo(step) => self.run_to_step(session, step),
            DebugCommand::InspectState => self.inspect_current_state(session),
            DebugCommand::InspectQubit(qubit) => self.inspect_qubit(session, qubit),
            DebugCommand::ShowEntanglement => self.show_entanglement_map(session),
            DebugCommand::ShowAmplitudes => self.show_amplitude_distribution(session),
            DebugCommand::SetWatchpoint(wp) => self.set_watchpoint(wp),
            DebugCommand::ClearWatchpoint(id) => self.clear_watchpoint(id),
            DebugCommand::ShowCircuit => self.show_circuit_progress(session),
            DebugCommand::Export(format) => self.export_visualization(format),
            DebugCommand::Quit => self.quit_session(),
        }
    }

    /// Generate comprehensive visualization data
    pub fn generate_visualization(
        &mut self,
        state: &[Complex64],
        num_qubits: usize,
        step: usize,
    ) -> Result<VisualizationData, QuantRS2Error> {
        let mut viz_data = VisualizationData {
            step,
            timestamp: Instant::now(),
            state_vector_viz: None,
            bloch_spheres: None,
            density_matrix_viz: None,
            entanglement_graph: None,
            circuit_diagram: None,
            amplitude_histogram: None,
            phase_diagram: None,
            measurement_probabilities: None,
        };

        // State vector visualization
        if self.config.viz_config.enable_3d_viz {
            viz_data.state_vector_viz = Some(self.create_state_vector_visualization(state)?);
        }

        // Bloch sphere visualization for single qubits
        if self.config.viz_config.enable_bloch_sphere && num_qubits <= 4 {
            viz_data.bloch_spheres = Some(self.create_bloch_sphere_visualization(state, num_qubits)?);
        }

        // Density matrix visualization
        if self.config.viz_config.enable_density_matrix {
            viz_data.density_matrix_viz = Some(self.create_density_matrix_visualization(state)?);
        }

        // Entanglement graph
        if self.config.viz_config.enable_entanglement_graph {
            viz_data.entanglement_graph = Some(self.create_entanglement_graph(state, num_qubits)?);
        }

        // Amplitude and phase visualizations
        viz_data.amplitude_histogram = Some(self.create_amplitude_histogram(state)?);
        viz_data.phase_diagram = Some(self.create_phase_diagram(state)?);
        viz_data.measurement_probabilities = Some(self.calculate_measurement_probabilities(state)?);

        // Cache the visualization
        self.visualizations.insert(step, viz_data.clone());

        Ok(viz_data)
    }

    /// Create state vector visualization
    fn create_state_vector_visualization(
        &self,
        state: &[Complex64],
    ) -> Result<StateVectorVisualization, QuantRS2Error> {
        let amplitudes: Vec<f64> = state.iter().map(|c| c.norm()).collect();
        let phases: Vec<f64> = state.iter().map(|c| c.arg()).collect();

        // Create 3D coordinates for visualization
        let mut coordinates = Vec::new();
        for (i, (amp, phase)) in amplitudes.iter().zip(phases.iter()).enumerate() {
            coordinates.push(Point3D {
                x: i as f64,
                y: amp * phase.cos(),
                z: amp * phase.sin(),
                color: self.phase_to_color(*phase),
                size: *amp,
            });
        }

        Ok(StateVectorVisualization {
            coordinates,
            max_amplitude: amplitudes.iter().cloned().fold(0.0, f64::max),
            color_map: self.config.viz_config.color_scheme.phase_colors.clone(),
        })
    }

    /// Create Bloch sphere visualization
    fn create_bloch_sphere_visualization(
        &self,
        state: &[Complex64],
        num_qubits: usize,
    ) -> Result<Vec<BlochSphere>, QuantRS2Error> {
        let mut bloch_spheres = Vec::new();

        for qubit in 0..num_qubits {
            let reduced_state = self.get_reduced_density_matrix(state, qubit, num_qubits)?;
            let bloch_vector = self.density_matrix_to_bloch_vector(&reduced_state)?;

            bloch_spheres.push(BlochSphere {
                qubit_index: qubit,
                x: bloch_vector[0],
                y: bloch_vector[1],
                z: bloch_vector[2],
                purity: self.calculate_state_purity(&reduced_state)?,
            });
        }

        Ok(bloch_spheres)
    }

    /// Create density matrix visualization
    fn create_density_matrix_visualization(
        &self,
        state: &[Complex64],
    ) -> Result<DensityMatrixVisualization, QuantRS2Error> {
        let density_matrix = self.state_to_density_matrix(state)?;

        // Extract magnitude and phase matrices
        let dim = state.len();
        let mut magnitude_matrix = Array2::<f64>::zeros((dim, dim));
        let mut phase_matrix = Array2::<f64>::zeros((dim, dim));

        for i in 0..dim {
            for j in 0..dim {
                magnitude_matrix[[i, j]] = density_matrix[[i, j]].norm();
                phase_matrix[[i, j]] = density_matrix[[i, j]].arg();
            }
        }

        Ok(DensityMatrixVisualization {
            magnitude_matrix: magnitude_matrix.into_raw_vec(),
            phase_matrix: phase_matrix.into_raw_vec(),
            dimension: dim,
            coherences: self.extract_coherences(&density_matrix)?,
        })
    }

    /// Create entanglement graph visualization
    fn create_entanglement_graph(
        &self,
        state: &[Complex64],
        num_qubits: usize,
    ) -> Result<EntanglementGraph, QuantRS2Error> {
        let mut nodes = Vec::new();
        let mut edges = Vec::new();

        // Create nodes for each qubit
        for i in 0..num_qubits {
            nodes.push(GraphNode {
                id: i,
                label: format!("Q{}", i),
                size: 1.0,
                color: self.config.viz_config.color_scheme.foreground.clone(),
            });
        }

        // Calculate pairwise entanglement and create edges
        for i in 0..num_qubits {
            for j in (i + 1)..num_qubits {
                let entanglement = self.calculate_bipartite_entanglement(state, i, j, num_qubits)?;
                if entanglement > 0.1 {  // Threshold for visualization
                    edges.push(GraphEdge {
                        source: i,
                        target: j,
                        weight: entanglement,
                        color: self.entanglement_to_color(entanglement),
                    });
                }
            }
        }

        Ok(EntanglementGraph {
            nodes,
            edges,
            layout: GraphLayout::ForceDirected,
        })
    }

    /// Create amplitude histogram
    fn create_amplitude_histogram(&self, state: &[Complex64]) -> Result<AmplitudeHistogram, QuantRS2Error> {
        let mut bins = Vec::new();

        for (i, amplitude) in state.iter().enumerate() {
            let magnitude = amplitude.norm();
            if magnitude > 1e-6 {  // Threshold for visualization
                bins.push(HistogramBin {
                    state_index: i,
                    state_label: format!("|{:b}⟩", i),
                    amplitude: magnitude,
                    probability: magnitude * magnitude,
                    phase: amplitude.arg(),
                });
            }
        }

        // Sort by probability
        bins.sort_by(|a, b| b.probability.partial_cmp(&a.probability).unwrap_or(std::cmp::Ordering::Equal));

        Ok(AmplitudeHistogram {
            bins: bins.into_iter().take(20).collect(),  // Top 20 states
            total_states: state.len(),
        })
    }

    /// Create phase diagram
    fn create_phase_diagram(&self, state: &[Complex64]) -> Result<PhaseDiagram, QuantRS2Error> {
        let mut phase_points = Vec::new();

        for (i, amplitude) in state.iter().enumerate() {
            let magnitude = amplitude.norm();
            if magnitude > 1e-6 {
                phase_points.push(PhasePoint {
                    state_index: i,
                    real_part: amplitude.re,
                    imaginary_part: amplitude.im,
                    magnitude,
                    phase: amplitude.arg(),
                });
            }
        }

        Ok(PhaseDiagram {
            points: phase_points,
            unit_circle: true,
        })
    }

    /// Generate circuit diagram
    fn generate_circuit_diagram(
        &mut self,
        circuit: &[QuantumGate],
        num_qubits: usize,
    ) -> Result<CircuitDiagram, QuantRS2Error> {
        let mut layers = Vec::new();
        let mut current_layer = CircuitLayer {
            gates: Vec::new(),
            time_index: 0,
        };

        // Group gates into layers
        let mut used_qubits = vec![false; num_qubits];

        for gate in circuit {
            let gate_qubits: Vec<_> = gate.target_qubits().iter()
                .chain(gate.control_qubits().unwrap_or(&[]).iter())
                .copied()
                .collect();

            // Check if gate can be added to current layer
            let can_add = gate_qubits.iter().all(|&q| !used_qubits[q]);

            if !can_add {
                // Start new layer
                if !current_layer.gates.is_empty() {
                    layers.push(current_layer);
                    current_layer = CircuitLayer {
                        gates: Vec::new(),
                        time_index: layers.len(),
                    };
                }
                used_qubits.fill(false);
            }

            // Mark qubits as used
            for &q in &gate_qubits {
                used_qubits[q] = true;
            }

            current_layer.gates.push(self.gate_to_visual(gate)?);
        }

        if !current_layer.gates.is_empty() {
            layers.push(current_layer);
        }

        Ok(CircuitDiagram {
            num_qubits,
            layers,
            qubit_labels: (0..num_qubits).map(|i| format!("q{}", i)).collect(),
        })
    }

    /// Convert gate to visual representation
    fn gate_to_visual(&self, gate: &QuantumGate) -> Result<VisualGate, QuantRS2Error> {
        let symbol = match gate.gate_type() {
            GateType::X => "X",
            GateType::Y => "Y",
            GateType::Z => "Z",
            GateType::H => "H",
            GateType::CNOT => "●",
            GateType::S => "S",
            GateType::T => "T",
            _ => "?",
        };

        Ok(VisualGate {
            gate_type: format!("{:?}", gate.gate_type()),
            symbol: symbol.to_string(),
            target_qubits: gate.target_qubits().to_vec(),
            control_qubits: gate.control_qubits().map(|c| c.to_vec()),
            parameters: Vec::new(),  // Would extract parameters for parametric gates
        })
    }

    /// Export visualization in specified format
    fn export_visualization(&self, format: OutputFormat) -> Result<CommandResult, QuantRS2Error> {
        let current_viz = self.visualizations.get(&self.current_step)
            .ok_or_else(|| QuantRS2Error::InvalidOperation("No visualization data available".into()))?;

        let export_data = match format {
            OutputFormat::SVG => self.export_as_svg(current_viz)?,
            OutputFormat::PNG => self.export_as_png(current_viz)?,
            OutputFormat::HTML => self.export_as_html(current_viz)?,
            OutputFormat::JSON => self.export_as_json(current_viz)?,
            OutputFormat::LaTeX => self.export_as_latex(current_viz)?,
            OutputFormat::ASCII => self.export_as_ascii(current_viz)?,
        };

        Ok(CommandResult {
            success: true,
            message: format!("Exported visualization as {:?}", format),
            data: Some(export_data),
            visualization: None,
        })
    }

    /// Export as SVG
    fn export_as_svg(&self, viz: &VisualizationData) -> Result<String, QuantRS2Error> {
        let mut svg = String::from(r#"<svg xmlns="http://www.w3.org/2000/svg" width="800" height="600">"#);

        // Add visualization elements
        if let Some(amp_hist) = &viz.amplitude_histogram {
            svg.push_str(&self.amplitude_histogram_to_svg(amp_hist)?);
        }

        svg.push_str("</svg>");
        Ok(svg)
    }

    /// Export as HTML with interactive features
    fn export_as_html(&self, viz: &VisualizationData) -> Result<String, QuantRS2Error> {
        let html = format!(r#"
<!DOCTYPE html>
<html>
<head>
    <title>Quantum Circuit Debug Visualization</title>
    <script src="https://d3js.org/d3.v7.min.js"></script>
    <style>
        body {{ font-family: Arial, sans-serif; }}
        .container {{ max-width: 1200px; margin: 0 auto; }}
        .viz-section {{ margin: 20px 0; padding: 20px; border: 1px solid #ccc; }}
    </style>
</head>
<body>
    <div class="container">
        <h1>Quantum Circuit Debug - Step {}</h1>
        <div id="state-vector" class="viz-section"></div>
        <div id="bloch-spheres" class="viz-section"></div>
        <div id="entanglement" class="viz-section"></div>
    </div>
    <script>
        // Visualization code would go here
    </script>
</body>
</html>"#, viz.step);

        Ok(html)
    }

    /// Export as JSON
    fn export_as_json(&self, viz: &VisualizationData) -> Result<String, QuantRS2Error> {
        serde_json::to_string_pretty(viz)
            .map_err(|e| QuantRS2Error::SerializationError(e.to_string()))
    }

    /// Export as LaTeX
    fn export_as_latex(&self, viz: &VisualizationData) -> Result<String, QuantRS2Error> {
        let mut latex = String::from(r"\documentclass{article}\n");
        latex.push_str(r"\usepackage{qcircuit}\n");
        latex.push_str(r"\usepackage{amsmath}\n");
        latex.push_str(r"\begin{document}\n");

        // Add circuit diagram if available
        if let Some(circuit) = &viz.circuit_diagram {
            latex.push_str(&self.circuit_to_latex(circuit)?);
        }

        latex.push_str(r"\end{document}");
        Ok(latex)
    }

    /// Export as ASCII art
    fn export_as_ascii(&self, viz: &VisualizationData) -> Result<String, QuantRS2Error> {
        let mut ascii = String::new();

        // ASCII circuit diagram
        if let Some(circuit) = &viz.circuit_diagram {
            ascii.push_str(&self.circuit_to_ascii(circuit)?);
        }

        // ASCII amplitude bar chart
        if let Some(amp_hist) = &viz.amplitude_histogram {
            ascii.push_str("\n\nAmplitude Distribution:\n");
            ascii.push_str(&self.amplitude_histogram_to_ascii(amp_hist)?);
        }

        Ok(ascii)
    }

    // Helper methods for various conversions and calculations
    fn phase_to_color(&self, phase: f64) -> String {
        let colors = &self.config.viz_config.color_scheme.phase_colors;
        let index = ((phase + std::f64::consts::PI) / (2.0 * std::f64::consts::PI) * colors.len() as f64) as usize;
        colors[index.min(colors.len() - 1)].clone()
    }

    fn entanglement_to_color(&self, entanglement: f64) -> String {
        let gradient = &self.config.viz_config.color_scheme.entanglement_gradient;
        let index = (entanglement * (gradient.len() - 1) as f64) as usize;
        gradient[index.min(gradient.len() - 1)].clone()
    }

    fn get_reduced_density_matrix(
        &self,
        state: &[Complex64],
        qubit: usize,
        num_qubits: usize,
    ) -> Result<Array2<Complex64>, QuantRS2Error> {
        // Simplified reduced density matrix calculation
        let mut reduced = Array2::zeros((2, 2));

        for i in 0..(1 << num_qubits) {
            let bit = (i >> qubit) & 1;
            for j in 0..(1 << num_qubits) {
                let bit_j = (j >> qubit) & 1;
                if bit == bit_j {
                    reduced[[bit, bit]] += state[i].conj() * state[j];
                }
            }
        }

        Ok(reduced)
    }

    fn density_matrix_to_bloch_vector(&self, density: &Array2<Complex64>) -> Result<Vec<f64>, QuantRS2Error> {
        let x = 2.0 * density[[0, 1]].re;
        let y = 2.0 * density[[0, 1]].im;
        let z = density[[0, 0]].re - density[[1, 1]].re;
        Ok(vec![x, y, z])
    }

    fn state_to_density_matrix(&self, state: &[Complex64]) -> Result<Array2<Complex64>, QuantRS2Error> {
        let dim = state.len();
        let mut density = Array2::zeros((dim, dim));

        for i in 0..dim {
            for j in 0..dim {
                density[[i, j]] = state[i] * state[j].conj();
            }
        }

        Ok(density)
    }

    fn calculate_state_purity(&self, density: &Array2<Complex64>) -> Result<f64, QuantRS2Error> {
        let trace_rho_squared = density.dot(density).diag().iter().sum::<Complex64>();
        Ok(trace_rho_squared.re)
    }

    fn extract_coherences(&self, density: &Array2<Complex64>) -> Result<Vec<Coherence>, QuantRS2Error> {
        let mut coherences = Vec::new();
        let dim = density.nrows();

        for i in 0..dim {
            for j in (i + 1)..dim {
                let coherence = density[[i, j]].norm();
                if coherence > 1e-6 {
                    coherences.push(Coherence {
                        state1: i,
                        state2: j,
                        magnitude: coherence,
                        phase: density[[i, j]].arg(),
                    });
                }
            }
        }

        Ok(coherences)
    }

    fn calculate_bipartite_entanglement(
        &self,
        state: &[Complex64],
        qubit1: usize,
        qubit2: usize,
        num_qubits: usize,
    ) -> Result<f64, QuantRS2Error> {
        // Simplified bipartite entanglement measure
        let mut correlation = 0.0;

        for i in 0..(1 << num_qubits) {
            let bit1 = (i >> qubit1) & 1;
            let bit2 = (i >> qubit2) & 1;

            if bit1 == bit2 {
                correlation += state[i].norm_sqr();
            } else {
                correlation -= state[i].norm_sqr();
            }
        }

        Ok((1.0 - correlation.abs()) / 2.0)
    }

    fn calculate_measurement_probabilities(&self, state: &[Complex64]) -> Result<Vec<f64>, QuantRS2Error> {
        Ok(state.iter().map(|c| c.norm_sqr()).collect())
    }

    fn create_initial_visualization(
        &mut self,
        state: &[Complex64],
        num_qubits: usize,
    ) -> Result<VisualizationData, QuantRS2Error> {
        self.generate_visualization(state, num_qubits, 0)
    }

    // Interactive debugging methods
    fn continue_execution(&mut self, session: &mut InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        // Continue execution until breakpoint or end
        Ok(CommandResult {
            success: true,
            message: "Continued execution".to_string(),
            data: None,
            visualization: None,
        })
    }

    fn step_execution(&mut self, session: &mut InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        // Execute single step
        Ok(CommandResult {
            success: true,
            message: "Stepped to next gate".to_string(),
            data: None,
            visualization: None,
        })
    }

    fn step_into(&mut self, _session: &mut InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        Ok(CommandResult {
            success: true,
            message: "Stepped into gate decomposition".to_string(),
            data: None,
            visualization: None,
        })
    }

    fn step_out(&mut self, _session: &mut InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        Ok(CommandResult {
            success: true,
            message: "Stepped out of decomposition".to_string(),
            data: None,
            visualization: None,
        })
    }

    fn run_to_step(&mut self, _session: &mut InteractiveSession, step: usize) -> Result<CommandResult, QuantRS2Error> {
        Ok(CommandResult {
            success: true,
            message: format!("Running to step {}", step),
            data: None,
            visualization: None,
        })
    }

    fn inspect_current_state(&mut self, session: &InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        let viz = self.generate_visualization(&session.current_state, session.num_qubits, self.current_step)?;

        Ok(CommandResult {
            success: true,
            message: "Current state inspection".to_string(),
            data: Some(format!("State at step {}", self.current_step)),
            visualization: Some(viz),
        })
    }

    fn inspect_qubit(&mut self, session: &InteractiveSession, qubit: usize) -> Result<CommandResult, QuantRS2Error> {
        if qubit >= session.num_qubits {
            return Err(QuantRS2Error::InvalidInput(format!("Qubit {} out of range", qubit)));
        }

        let reduced_state = self.get_reduced_density_matrix(&session.current_state, qubit, session.num_qubits)?;
        let bloch_vector = self.density_matrix_to_bloch_vector(&reduced_state)?;

        Ok(CommandResult {
            success: true,
            message: format!("Qubit {} inspection", qubit),
            data: Some(format!("Bloch vector: ({:.3}, {:.3}, {:.3})", bloch_vector[0], bloch_vector[1], bloch_vector[2])),
            visualization: None,
        })
    }

    fn show_entanglement_map(&mut self, session: &InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        let entanglement_graph = self.create_entanglement_graph(&session.current_state, session.num_qubits)?;

        Ok(CommandResult {
            success: true,
            message: "Entanglement map".to_string(),
            data: Some(format!("{} entangled pairs detected", entanglement_graph.edges.len())),
            visualization: None,
        })
    }

    fn show_amplitude_distribution(&mut self, session: &InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        let amp_hist = self.create_amplitude_histogram(&session.current_state)?;

        Ok(CommandResult {
            success: true,
            message: "Amplitude distribution".to_string(),
            data: Some(format!("{} significant states", amp_hist.bins.len())),
            visualization: None,
        })
    }

    fn set_watchpoint(&mut self, watchpoint: WatchpointType) -> Result<CommandResult, QuantRS2Error> {
        let id = self.watchpoints.len();
        self.watchpoints.push((id, watchpoint, true));

        Ok(CommandResult {
            success: true,
            message: format!("Watchpoint {} set", id),
            data: None,
            visualization: None,
        })
    }

    fn clear_watchpoint(&mut self, id: usize) -> Result<CommandResult, QuantRS2Error> {
        if id < self.watchpoints.len() {
            self.watchpoints[id].2 = false;
            Ok(CommandResult {
                success: true,
                message: format!("Watchpoint {} cleared", id),
                data: None,
                visualization: None,
            })
        } else {
            Err(QuantRS2Error::InvalidInput(format!("Invalid watchpoint ID: {}", id)))
        }
    }

    fn show_circuit_progress(&mut self, session: &InteractiveSession) -> Result<CommandResult, QuantRS2Error> {
        let progress = self.current_step as f64 / session.circuit.len() as f64 * 100.0;

        Ok(CommandResult {
            success: true,
            message: format!("Circuit progress: {:.1}%", progress),
            data: Some(format!("Step {} of {}", self.current_step, session.circuit.len())),
            visualization: None,
        })
    }

    fn quit_session(&mut self) -> Result<CommandResult, QuantRS2Error> {
        self.interactive_session = None;

        Ok(CommandResult {
            success: true,
            message: "Debug session ended".to_string(),
            data: None,
            visualization: None,
        })
    }

    fn amplitude_histogram_to_svg(&self, hist: &AmplitudeHistogram) -> Result<String, QuantRS2Error> {
        let mut svg = String::new();
        let bar_width = 30.0;
        let max_height = 200.0;

        for (i, bin) in hist.bins.iter().enumerate() {
            let x = i as f64 * (bar_width + 5.0) + 50.0;
            let height = bin.probability * max_height;
            let y = 250.0 - height;

            let _ = write!(svg, r#"<rect x="{}" y="{}" width="{}" height="{}" fill="{}" />
                   <text x="{}" y="270" font-size="10" text-anchor="middle">{}</text>"#,
                x, y, bar_width, height,
                self.config.viz_config.color_scheme.amplitude_positive,
                x + bar_width / 2.0,
                bin.state_label);
        }

        Ok(svg)
    }

    fn circuit_to_latex(&self, circuit: &CircuitDiagram) -> Result<String, QuantRS2Error> {
        let mut latex = String::from(r"\begin{figure}[h]\n\centering\n\begin{qcircuit}\n");

        // Add qubit lines
        for i in 0..circuit.num_qubits {
            if i > 0 {
                latex.push_str(r" \\ ");
            }
            let _ = write!(latex, r"\lstick{{|{}⟩}}", circuit.qubit_labels[i]);

            // Add gates for this qubit
            for layer in &circuit.layers {
                latex.push_str(" & ");

                let gate_on_qubit = layer.gates.iter()
                    .find(|g| g.target_qubits.contains(&i));

                if let Some(gate) = gate_on_qubit {
                    let _ = write!(latex, r"\gate{{{}}}", gate.symbol);
                } else {
                    latex.push_str(r"\qw");
                }
            }
        }

        latex.push_str(r"\end{qcircuit}\n\end{figure}");
        Ok(latex)
    }

    fn circuit_to_ascii(&self, circuit: &CircuitDiagram) -> Result<String, QuantRS2Error> {
        let mut ascii = String::new();

        for i in 0..circuit.num_qubits {
            let _ = write!(ascii, "q{}: ", i);

            for layer in &circuit.layers {
                let gate_on_qubit = layer.gates.iter()
                    .find(|g| g.target_qubits.contains(&i));

                if let Some(gate) = gate_on_qubit {
                    let _ = write!(ascii, "-[{}]-", gate.symbol);
                } else {
                    ascii.push_str("-----");
                }
            }

            ascii.push('\n');
        }

        Ok(ascii)
    }

    fn amplitude_histogram_to_ascii(&self, hist: &AmplitudeHistogram) -> Result<String, QuantRS2Error> {
        let mut ascii = String::new();
        let max_bar_length = 40;

        for bin in &hist.bins {
            let bar_length = (bin.probability * max_bar_length as f64) as usize;
            let bar = "█".repeat(bar_length);

            let _ = writeln!(ascii, "{:>10} |{:<40} {:.3}",
                bin.state_label,
                bar,
                bin.probability);
        }

        Ok(ascii)
    }
}

// Data structures for visualization

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct VisualizationData {
    pub step: usize,
    pub timestamp: Instant,
    pub state_vector_viz: Option<StateVectorVisualization>,
    pub bloch_spheres: Option<Vec<BlochSphere>>,
    pub density_matrix_viz: Option<DensityMatrixVisualization>,
    pub entanglement_graph: Option<EntanglementGraph>,
    pub circuit_diagram: Option<CircuitDiagram>,
    pub amplitude_histogram: Option<AmplitudeHistogram>,
    pub phase_diagram: Option<PhaseDiagram>,
    pub measurement_probabilities: Option<Vec<f64>>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StateVectorVisualization {
    pub coordinates: Vec<Point3D>,
    pub max_amplitude: f64,
    pub color_map: Vec<String>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Point3D {
    pub x: f64,
    pub y: f64,
    pub z: f64,
    pub color: String,
    pub size: f64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct BlochSphere {
    pub qubit_index: usize,
    pub x: f64,
    pub y: f64,
    pub z: f64,
    pub purity: f64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DensityMatrixVisualization {
    pub magnitude_matrix: Vec<f64>,
    pub phase_matrix: Vec<f64>,
    pub dimension: usize,
    pub coherences: Vec<Coherence>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Coherence {
    pub state1: usize,
    pub state2: usize,
    pub magnitude: f64,
    pub phase: f64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct EntanglementGraph {
    pub nodes: Vec<GraphNode>,
    pub edges: Vec<GraphEdge>,
    pub layout: GraphLayout,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct GraphNode {
    pub id: usize,
    pub label: String,
    pub size: f64,
    pub color: String,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct GraphEdge {
    pub source: usize,
    pub target: usize,
    pub weight: f64,
    pub color: String,
}

#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
pub enum GraphLayout {
    ForceDirected,
    Circular,
    Hierarchical,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AmplitudeHistogram {
    pub bins: Vec<HistogramBin>,
    pub total_states: usize,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct HistogramBin {
    pub state_index: usize,
    pub state_label: String,
    pub amplitude: f64,
    pub probability: f64,
    pub phase: f64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PhaseDiagram {
    pub points: Vec<PhasePoint>,
    pub unit_circle: bool,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PhasePoint {
    pub state_index: usize,
    pub real_part: f64,
    pub imaginary_part: f64,
    pub magnitude: f64,
    pub phase: f64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CircuitDiagram {
    pub num_qubits: usize,
    pub layers: Vec<CircuitLayer>,
    pub qubit_labels: Vec<String>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CircuitLayer {
    pub gates: Vec<VisualGate>,
    pub time_index: usize,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct VisualGate {
    pub gate_type: String,
    pub symbol: String,
    pub target_qubits: Vec<usize>,
    pub control_qubits: Option<Vec<usize>>,
    pub parameters: Vec<f64>,
}

/// Interactive session state
pub struct InteractiveSession {
    pub circuit: Vec<QuantumGate>,
    pub current_state: Vec<Complex64>,
    pub num_qubits: usize,
    pub is_running: bool,
    pub command_history: Vec<DebugCommand>,
}

/// Interactive debug result
#[derive(Debug, Clone)]
pub struct InteractiveDebugResult {
    pub session_id: String,
    pub initial_viz: VisualizationData,
}

/// Command execution result
#[derive(Debug, Clone)]
pub struct CommandResult {
    pub success: bool,
    pub message: String,
    pub data: Option<String>,
    pub visualization: Option<VisualizationData>,
}

/// Analysis result for caching
#[derive(Debug, Clone)]
pub struct AnalysisResult {
    pub timestamp: Instant,
    pub entanglement_measures: HashMap<(usize, usize), f64>,
    pub quantum_discord: f64,
    pub mutual_information: HashMap<(usize, usize), f64>,
    pub concurrence: HashMap<(usize, usize), f64>,
    pub negativity: HashMap<(usize, usize), f64>,
}

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

    #[test]
    fn test_advanced_debugger_creation() {
        let debugger = AdvancedQuantumDebugger::new();
        assert!(debugger.config.enable_interactive);
        assert!(debugger.config.viz_config.enable_3d_viz);
    }

    #[test]
    fn test_visualization_generation() {
        let mut debugger = AdvancedQuantumDebugger::new();
        let state = vec![
            Complex64::new(1.0 / std::f64::consts::SQRT_2, 0.0),
            Complex64::new(1.0 / std::f64::consts::SQRT_2, 0.0),
        ];

        let viz = debugger.generate_visualization(&state, 1, 0).expect("visualization generation should succeed");
        assert!(viz.state_vector_viz.is_some());
        assert!(viz.amplitude_histogram.is_some());
    }

    #[test]
    fn test_interactive_session() {
        let mut debugger = AdvancedQuantumDebugger::new();
        let circuit = vec![
            QuantumGate::new(GateType::H, vec![0], None),
        ];
        let initial_state = vec![
            Complex64::new(1.0, 0.0),
            Complex64::new(0.0, 0.0),
        ];

        let result = debugger.start_interactive_session(&circuit, &initial_state, 1).expect("interactive session should start");
        assert!(!result.session_id.is_empty());
    }

    #[test]
    fn test_export_formats() {
        let debugger = AdvancedQuantumDebugger::new();
        let viz = VisualizationData {
            step: 0,
            timestamp: Instant::now(),
            state_vector_viz: None,
            bloch_spheres: None,
            density_matrix_viz: None,
            entanglement_graph: None,
            circuit_diagram: None,
            amplitude_histogram: Some(AmplitudeHistogram {
                bins: vec![
                    HistogramBin {
                        state_index: 0,
                        state_label: "|0⟩".to_string(),
                        amplitude: 0.707,
                        probability: 0.5,
                        phase: 0.0,
                    },
                ],
                total_states: 2,
            }),
            phase_diagram: None,
            measurement_probabilities: None,
        };

        let svg = debugger.export_as_svg(&viz).expect("SVG export should succeed");
        assert!(svg.contains("<svg"));

        let json = debugger.export_as_json(&viz).expect("JSON export should succeed");
        assert!(json.contains("amplitude_histogram"));
    }

    #[test]
    fn test_watchpoint_management() {
        let mut debugger = AdvancedQuantumDebugger::new();

        let wp = WatchpointType::AmplitudeWatch { qubit: 0, threshold: 0.5 };
        let result = debugger.set_watchpoint(wp).expect("set_watchpoint should succeed");
        assert!(result.success);
        assert_eq!(debugger.watchpoints.len(), 1);

        let clear_result = debugger.clear_watchpoint(0).expect("clear_watchpoint should succeed");
        assert!(clear_result.success);
        assert!(!debugger.watchpoints[0].2);  // Should be disabled
    }
}