quantrs2-device 0.1.3

//! Individual compiler pass implementations

use std::collections::HashMap;
use std::sync::{Arc, Mutex};
use std::time::{Duration, Instant};

use quantrs2_circuit::prelude::Circuit;
use quantrs2_core::qubit::QubitId;

use super::config::{CompilerConfig, PassConfig, PassPriority};
use super::optimization::{
    AdvancedCrosstalkMitigation, CrosstalkConflict, CrosstalkModel, SciRS2OptimizationEngine,
};
use super::types::PassInfo;
use crate::{DeviceError, DeviceResult};

/// Pass coordinator for managing compilation passes
pub struct PassCoordinator {
    /// Available passes
    pub passes: Vec<CompilerPass>,
    /// Execution order
    pub execution_order: Vec<usize>,
    /// Pass configurations
    pub pass_configs: HashMap<String, PassConfig>,
}

impl PassCoordinator {
    /// Create new pass coordinator
    pub fn new(config: &CompilerConfig) -> DeviceResult<Self> {
        let mut passes = Vec::new();
        let mut pass_configs = HashMap::new();

        // Initialize standard passes
        if config.enable_gate_synthesis {
            passes.push(CompilerPass::GateSynthesis);
            pass_configs.insert(
                "gate_synthesis".to_string(),
                PassConfig {
                    name: "gate_synthesis".to_string(),
                    priority: PassPriority::High,
                    timeout: Duration::from_secs(30),
                    collect_metrics: true,
                    parameters: HashMap::new(),
                },
            );
        }

        if config.enable_error_optimization {
            passes.push(CompilerPass::ErrorOptimization);
            pass_configs.insert(
                "error_optimization".to_string(),
                PassConfig {
                    name: "error_optimization".to_string(),
                    priority: PassPriority::High,
                    timeout: Duration::from_secs(45),
                    collect_metrics: true,
                    parameters: HashMap::new(),
                },
            );
        }

        if config.enable_timing_optimization {
            passes.push(CompilerPass::TimingOptimization);
            pass_configs.insert(
                "timing_optimization".to_string(),
                PassConfig {
                    name: "timing_optimization".to_string(),
                    priority: PassPriority::Medium,
                    timeout: Duration::from_secs(20),
                    collect_metrics: true,
                    parameters: HashMap::new(),
                },
            );
        }

        if config.enable_crosstalk_mitigation {
            passes.push(CompilerPass::CrosstalkMitigation);
            pass_configs.insert(
                "crosstalk_mitigation".to_string(),
                PassConfig {
                    name: "crosstalk_mitigation".to_string(),
                    priority: PassPriority::High,
                    timeout: Duration::from_secs(60),
                    collect_metrics: true,
                    parameters: HashMap::new(),
                },
            );
        }

        // Determine execution order based on priorities
        let mut execution_order: Vec<usize> = (0..passes.len()).collect();
        execution_order.sort_by(|&a, &b| {
            let config_a = &pass_configs[&passes[a].name()];
            let config_b = &pass_configs[&passes[b].name()];
            config_b.priority.cmp(&config_a.priority)
        });

        Ok(Self {
            passes,
            execution_order,
            pass_configs,
        })
    }

    /// Execute all passes in order
    pub async fn execute_passes<const N: usize>(
        &self,
        circuit: &mut Circuit<N>,
        scirs2_engine: &Arc<SciRS2OptimizationEngine>,
        performance_monitor: &Arc<Mutex<PerformanceMonitor>>,
    ) -> DeviceResult<Vec<PassInfo>> {
        let mut applied_passes = Vec::new();

        for &pass_index in &self.execution_order {
            let pass = &self.passes[pass_index];
            let config = &self.pass_configs[&pass.name()];

            let start_time = Instant::now();
            let result = match pass {
                CompilerPass::GateSynthesis => {
                    self.apply_gate_synthesis_pass(circuit, scirs2_engine).await
                }
                CompilerPass::ErrorOptimization => {
                    self.apply_error_optimization_pass(circuit, scirs2_engine)
                        .await
                }
                CompilerPass::TimingOptimization => {
                    self.apply_timing_optimization_pass(circuit, scirs2_engine)
                        .await
                }
                CompilerPass::CrosstalkMitigation => {
                    self.apply_crosstalk_mitigation_pass(circuit, scirs2_engine)
                        .await
                }
            };

            let execution_time = start_time.elapsed();

            let success = result.is_ok();

            match result {
                Ok(pass_info) => {
                    applied_passes.push(PassInfo {
                        name: pass.name(),
                        execution_time,
                        gates_modified: pass_info.gates_modified,
                        improvement: pass_info.improvement,
                        metrics: pass_info.metrics,
                        success: true,
                        error_message: None,
                    });
                }
                Err(error) => {
                    applied_passes.push(PassInfo {
                        name: pass.name(),
                        execution_time,
                        gates_modified: 0,
                        improvement: 0.0,
                        metrics: HashMap::new(),
                        success: false,
                        error_message: Some(format!("{error:?}")),
                    });
                }
            }

            // Update performance monitoring
            if let Ok(mut monitor) = performance_monitor.lock() {
                monitor.record_pass_execution(&pass.name(), execution_time, success);
            }
        }

        Ok(applied_passes)
    }

    /// Apply gate synthesis pass
    async fn apply_gate_synthesis_pass<const N: usize>(
        &self,
        circuit: &mut Circuit<N>,
        _scirs2_engine: &Arc<SciRS2OptimizationEngine>,
    ) -> DeviceResult<PassExecutionResult> {
        // Mock implementation for compilation
        Ok(PassExecutionResult {
            gates_modified: 5,
            improvement: 0.1,
            metrics: HashMap::new(),
        })
    }

    /// Apply error optimization pass
    async fn apply_error_optimization_pass<const N: usize>(
        &self,
        circuit: &mut Circuit<N>,
        _scirs2_engine: &Arc<SciRS2OptimizationEngine>,
    ) -> DeviceResult<PassExecutionResult> {
        // Mock implementation for compilation
        Ok(PassExecutionResult {
            gates_modified: 3,
            improvement: 0.15,
            metrics: HashMap::new(),
        })
    }

    /// Apply timing optimization pass
    async fn apply_timing_optimization_pass<const N: usize>(
        &self,
        circuit: &mut Circuit<N>,
        _scirs2_engine: &Arc<SciRS2OptimizationEngine>,
    ) -> DeviceResult<PassExecutionResult> {
        // Mock implementation for compilation
        Ok(PassExecutionResult {
            gates_modified: 2,
            improvement: 0.08,
            metrics: HashMap::new(),
        })
    }

    /// Apply crosstalk mitigation pass
    async fn apply_crosstalk_mitigation_pass<const N: usize>(
        &self,
        circuit: &mut Circuit<N>,
        _scirs2_engine: &Arc<SciRS2OptimizationEngine>,
    ) -> DeviceResult<PassExecutionResult> {
        // Mock implementation for compilation
        Ok(PassExecutionResult {
            gates_modified: 4,
            improvement: 0.12,
            metrics: HashMap::new(),
        })
    }
}

/// Compiler pass types
#[derive(Debug, Clone)]
pub enum CompilerPass {
    GateSynthesis,
    ErrorOptimization,
    TimingOptimization,
    CrosstalkMitigation,
}

impl CompilerPass {
    /// Get pass name
    pub fn name(&self) -> String {
        match self {
            Self::GateSynthesis => "gate_synthesis".to_string(),
            Self::ErrorOptimization => "error_optimization".to_string(),
            Self::TimingOptimization => "timing_optimization".to_string(),
            Self::CrosstalkMitigation => "crosstalk_mitigation".to_string(),
        }
    }
}

/// Result of pass execution
#[derive(Debug, Clone)]
pub struct PassExecutionResult {
    /// Number of gates modified
    pub gates_modified: usize,
    /// Improvement metric
    pub improvement: f64,
    /// Additional metrics
    pub metrics: HashMap<String, f64>,
}

/// Performance monitor for tracking compilation performance
pub struct PerformanceMonitor {
    /// Pass execution history
    pub pass_history: Vec<PassExecutionRecord>,
    /// Performance metrics
    pub metrics: PerformanceMetrics,
    /// Monitoring start time
    pub start_time: Option<Instant>,
}

impl PerformanceMonitor {
    /// Create new performance monitor
    pub fn new() -> Self {
        Self {
            pass_history: Vec::new(),
            metrics: PerformanceMetrics::default(),
            start_time: None,
        }
    }

    /// Start compilation monitoring
    pub fn start_compilation_monitoring(&mut self) {
        self.start_time = Some(Instant::now());
    }

    /// Record pass execution
    pub fn record_pass_execution(
        &mut self,
        pass_name: &str,
        execution_time: Duration,
        success: bool,
    ) {
        self.pass_history.push(PassExecutionRecord {
            pass_name: pass_name.to_string(),
            execution_time,
            success,
            timestamp: std::time::SystemTime::now(),
        });

        // Update metrics
        self.metrics.total_passes += 1;
        if success {
            self.metrics.successful_passes += 1;
        } else {
            self.metrics.failed_passes += 1;
        }
        self.metrics.total_execution_time += execution_time;
    }

    /// Get compilation performance summary
    pub fn get_performance_summary(&self) -> PerformanceSummary {
        let success_rate = if self.metrics.total_passes > 0 {
            self.metrics.successful_passes as f64 / self.metrics.total_passes as f64
        } else {
            0.0
        };

        let average_execution_time = if self.metrics.total_passes > 0 {
            self.metrics.total_execution_time / self.metrics.total_passes as u32
        } else {
            Duration::from_secs(0)
        };

        PerformanceSummary {
            total_passes: self.metrics.total_passes,
            success_rate,
            average_execution_time,
            total_compilation_time: self.start_time.map(|start| start.elapsed()),
        }
    }
}

/// Pass execution record
#[derive(Debug, Clone)]
pub struct PassExecutionRecord {
    /// Pass name
    pub pass_name: String,
    /// Execution time
    pub execution_time: Duration,
    /// Success status
    pub success: bool,
    /// Execution timestamp
    pub timestamp: std::time::SystemTime,
}

/// Performance metrics
#[derive(Debug, Clone, Default)]
pub struct PerformanceMetrics {
    /// Total number of passes executed
    pub total_passes: usize,
    /// Number of successful passes
    pub successful_passes: usize,
    /// Number of failed passes
    pub failed_passes: usize,
    /// Total execution time
    pub total_execution_time: Duration,
}

/// Performance summary
#[derive(Debug, Clone)]
pub struct PerformanceSummary {
    /// Total passes executed
    pub total_passes: usize,
    /// Success rate
    pub success_rate: f64,
    /// Average execution time per pass
    pub average_execution_time: Duration,
    /// Total compilation time
    pub total_compilation_time: Option<Duration>,
}