//! JIT profiler for performance analysis

use crate::advanced_jit_compilation::config::{
    JitCompilerConfig, ProfilerConfig, ProfilingSessionConfig,
};
use crate::advanced_jit_compilation::llvm_engine::{CodeSizeMetrics, CompilationError};
use crate::error::CoreResult;
use std::collections::HashMap;
use std::time::{Duration, Instant};

/// JIT profiler for performance analysis
#[derive(Debug)]
pub struct JitProfiler {
    /// Compilation profiles
    #[allow(dead_code)]
    compilation_profiles: HashMap<String, CompilationProfile>,
    /// Execution profiles
    #[allow(dead_code)]
    execution_profiles: HashMap<String, ExecutionProfile>,
    /// Profiling configuration
    #[allow(dead_code)]
    config: ProfilerConfig,
    /// Active profiling sessions
    #[allow(dead_code)]
    active_sessions: HashMap<String, ProfilingSession>,
}

/// Compilation profile
#[derive(Debug, Clone)]
pub struct CompilationProfile {
    /// Compilation times
    pub compilation_times: Vec<Duration>,
    /// Optimization effectiveness
    pub optimization_effectiveness: HashMap<String, f64>,
    /// Code size metrics
    pub code_size_metrics: CodeSizeMetrics,
    /// Compilation errors
    pub compilationerrors: Vec<CompilationError>,
}

/// Execution profile
#[derive(Debug, Clone)]
pub struct ExecutionProfile {
    /// Execution times
    pub execution_times: Vec<Duration>,
    /// Performance counters
    pub performance_counters: PerformanceCounters,
    /// Hotspot analysis
    pub hotspots: Vec<Hotspot>,
    /// Optimization opportunities
    pub optimization_opportunities: Vec<OptimizationOpportunity>,
}

/// Performance counters
#[derive(Debug, Clone)]
pub struct PerformanceCounters {
    /// CPU cycles
    pub cpu_cycles: u64,
    /// Instructions executed
    pub instructions: u64,
    /// Branch mispredictions
    pub branch_misses: u64,
    /// Cache misses
    pub cache_misses: u64,
    /// Memory bandwidth utilization
    pub memorybandwidth: f64,
}

/// Hotspot information
#[derive(Debug, Clone)]
pub struct Hotspot {
    /// Function name
    pub function_name: String,
    /// Execution percentage
    pub execution_percentage: f64,
    /// Call count
    pub call_count: u64,
    /// Average duration
    pub avg_duration: Duration,
    /// Optimization suggestions
    pub suggestions: Vec<String>,
}

/// Optimization opportunity
#[derive(Debug, Clone)]
pub struct OptimizationOpportunity {
    /// Opportunity type
    pub opportunity_type: OpportunityType,
    /// Potential improvement
    pub potential_improvement: f64,
    /// Implementation complexity
    pub complexity: ComplexityLevel,
    /// Description
    pub description: String,
}

/// Types of optimization opportunities
#[derive(Debug, Clone)]
pub enum OpportunityType {
    Vectorization,
    LoopUnrolling,
    MemoryAccessOptimization,
    BranchOptimization,
    InstructionLevelParallelism,
    DataLayoutOptimization,
}

/// Complexity levels for implementing optimizations
#[derive(Debug, Clone)]
pub enum ComplexityLevel {
    Low,
    Medium,
    High,
    Expert,
}

/// Active profiling session
#[derive(Debug)]
pub struct ProfilingSession {
    /// Session ID
    pub sessionid: String,
    /// Start time
    pub start_time: Instant,
    /// Collected samples
    pub samples: Vec<ProfilingSample>,
    /// Session configuration
    pub config: ProfilingSessionConfig,
}

/// Profiling sample
#[derive(Debug, Clone)]
pub struct ProfilingSample {
    /// Timestamp
    pub timestamp: Instant,
    /// Function name
    pub function_name: String,
    /// Performance metrics
    pub metrics: PerformanceCounters,
    /// Stack trace
    pub stack_trace: Vec<String>,
}

/// Profiler analytics
#[derive(Debug, Clone)]
pub struct ProfilerAnalytics {
    /// Total profiling sessions
    pub total_sessions: u64,
    /// Average execution time
    pub avgexecution_time: Duration,
    /// Hotspot functions
    pub hotspots: Vec<Hotspot>,
    /// Optimization opportunities
    pub opportunities: Vec<OptimizationOpportunity>,
}

impl JitProfiler {
    pub fn new(config: &JitCompilerConfig) -> CoreResult<Self> {
        Ok(Self {
            compilation_profiles: HashMap::new(),
            execution_profiles: HashMap::new(),
            config: ProfilerConfig {
                enable_execution_profiling: true,
                enable_compilation_profiling: true,
                samplingrate: 0.1,
                retention_hours: 24,
                enable_hotspot_detection: true,
                hotspot_threshold: 0.05,
            },
            active_sessions: HashMap::new(),
        })
    }

    pub fn start_profiling(&mut self, _kernelname: &str) -> CoreResult<()> {
        // Simplified implementation
        Ok(())
    }

    pub fn record_execution(
        &mut self,
        _kernel_name: &str,
        execution_time: Duration,
    ) -> CoreResult<()> {
        // Simplified implementation
        Ok(())
    }

    pub fn get_analytics(&self) -> ProfilerAnalytics {
        ProfilerAnalytics {
            total_sessions: 0,
            avgexecution_time: Duration::from_micros(100),
            hotspots: vec![],
            opportunities: vec![],
        }
    }
}
