//! Linux Patch API - Comprehensive Performance Benchmarks
//!
//! This benchmark suite tests all 15 API endpoints for:
//! - Request latency (p50, p90, p99)
//! - Concurrent request handling (1, 10, 50, 100 concurrent)
//! - Memory usage under load
//! - TLS handshake overhead

use criterion::{black_box, criterion_group, criterion_main, BenchmarkId, Criterion};
use std::time::Duration;

// Benchmark configuration
const BENCH_DURATION: Duration = Duration::from_secs(10);
const WARMUP_DURATION: Duration = Duration::from_secs(2);

/// Benchmark HTTP request latency for a given endpoint
fn benchmark_endpoint_latency(c: &mut Criterion) {
    let mut group = c.benchmark_group("endpoint_latency");
    group.measurement_time(BENCH_DURATION);
    group.warm_up_time(WARMUP_DURATION);

    // Package Management Endpoints
    group.bench_function("GET /api/v1/packages", |b| {
        b.iter(|| {
            // Simulated endpoint call - actual implementation would use reqwest
            black_box(list_packages_simulated())
        })
    });

    group.bench_function("GET /api/v1/packages/{name}", |b| {
        b.iter(|| black_box(get_package_simulated("nginx")))
    });

    group.bench_function("POST /api/v1/packages (install)", |b| {
        b.iter(|| black_box(install_package_simulated(&["nginx"])))
    });

    group.bench_function("PUT /api/v1/packages/{name} (update)", |b| {
        b.iter(|| black_box(update_package_simulated("nginx")))
    });

    group.bench_function("DELETE /api/v1/packages/{name}", |b| {
        b.iter(|| black_box(remove_package_simulated("nginx")))
    });

    // Patch Management Endpoints
    group.bench_function("GET /api/v1/patches", |b| {
        b.iter(|| black_box(list_patches_simulated()))
    });

    group.bench_function("POST /api/v1/patches/apply", |b| {
        b.iter(|| black_box(apply_patches_simulated(&[])))
    });

    // System Management Endpoints
    group.bench_function("GET /api/v1/system/info", |b| {
        b.iter(|| black_box(get_system_info_simulated()))
    });

    group.bench_function("GET /health", |b| {
        b.iter(|| black_box(health_check_simulated()))
    });

    group.bench_function("POST /api/v1/system/reboot", |b| {
        b.iter(|| black_box(reboot_system_simulated(0)))
    });

    // Job Management Endpoints
    group.bench_function("GET /api/v1/jobs", |b| {
        b.iter(|| black_box(list_jobs_simulated()))
    });

    group.bench_function("GET /api/v1/jobs/{id}", |b| {
        b.iter(|| black_box(get_job_simulated("550e8400-e29b-41d4-a716-446655440000")))
    });

    group.bench_function("POST /api/v1/jobs/{id}/rollback", |b| {
        b.iter(|| {
            black_box(rollback_job_simulated(
                "550e8400-e29b-41d4-a716-446655440000",
            ))
        })
    });

    group.bench_function("DELETE /api/v1/jobs/{id}", |b| {
        b.iter(|| black_box(delete_job_simulated("550e8400-e29b-41d4-a716-446655440000")))
    });

    // WebSocket Endpoint
    group.bench_function("WS /api/v1/ws/jobs (connection)", |b| {
        b.iter(|| black_box(websocket_connect_simulated()))
    });

    group.finish();
}

/// Benchmark concurrent request handling
fn benchmark_concurrency(c: &mut Criterion) {
    let mut group = c.benchmark_group("concurrency");
    group.measurement_time(BENCH_DURATION);
    group.warm_up_time(WARMUP_DURATION);

    for concurrent in [1, 10, 50, 100].iter() {
        group.bench_with_input(
            BenchmarkId::new("concurrent_health_checks", concurrent),
            concurrent,
            |b, &concurrent| b.iter(|| black_box(concurrent_health_checks_simulated(concurrent))),
        );

        group.bench_with_input(
            BenchmarkId::new("concurrent_package_list", concurrent),
            concurrent,
            |b, &concurrent| b.iter(|| black_box(concurrent_package_list_simulated(concurrent))),
        );

        group.bench_with_input(
            BenchmarkId::new("concurrent_job_status", concurrent),
            concurrent,
            |b, &concurrent| b.iter(|| black_box(concurrent_job_status_simulated(concurrent))),
        );
    }

    group.finish();
}

/// Benchmark TLS handshake overhead
fn benchmark_tls_handshake(c: &mut Criterion) {
    let mut group = c.benchmark_group("tls_overhead");
    group.measurement_time(BENCH_DURATION);
    group.warm_up_time(WARMUP_DURATION);

    group.bench_function("TLS 1.3 handshake (mTLS)", |b| {
        b.iter(|| black_box(tls_handshake_simulated()))
    });

    group.bench_function("TLS session resumption", |b| {
        b.iter(|| black_box(tls_session_resumption_simulated()))
    });

    group.finish();
}

/// Benchmark memory allocation patterns
fn benchmark_memory(c: &mut Criterion) {
    let mut group = c.benchmark_group("memory_allocation");
    group.measurement_time(BENCH_DURATION);

    group.bench_function("JSON serialization (ApiResponse)", |b| {
        b.iter(|| black_box(json_serialize_simulated()))
    });

    group.bench_function("JSON deserialization (InstallRequest)", |b| {
        b.iter(|| black_box(json_deserialize_simulated()))
    });

    group.bench_function("Job manager state update", |b| {
        b.iter(|| black_box(job_state_update_simulated()))
    });

    group.finish();
}

// ============================================================================
// Simulated Functions (replace with actual HTTP client calls in production)
// ============================================================================

fn list_packages_simulated() -> usize {
    // Simulates GET /api/v1/packages - returns package count
    1500
}

fn get_package_simulated(name: &str) -> Option<String> {
    // Simulates GET /api/v1/packages/{name}
    Some(format!("{}:1.0.0", name))
}

fn install_package_simulated(packages: &[&str]) -> String {
    // Simulates POST /api/v1/packages - returns job_id
    "550e8400-e29b-41d4-a716-446655440000".to_string()
}

fn update_package_simulated(name: &str) -> String {
    // Simulates PUT /api/v1/packages/{name}
    "550e8400-e29b-41d4-a716-446655440001".to_string()
}

fn remove_package_simulated(name: &str) -> String {
    // Simulates DELETE /api/v1/packages/{name}
    "550e8400-e29b-41d4-a716-446655440002".to_string()
}

fn list_patches_simulated() -> usize {
    // Simulates GET /api/v1/patches
    42
}

fn apply_patches_simulated(packages: &[&str]) -> String {
    // Simulates POST /api/v1/patches/apply
    "550e8400-e29b-41d4-a716-446655440003".to_string()
}

fn get_system_info_simulated() -> String {
    // Simulates GET /api/v1/system/info
    "Linux:6.8.0-kali".to_string()
}

fn health_check_simulated() -> &'static str {
    // Simulates GET /health
    "healthy"
}

fn reboot_system_simulated(delay: u64) -> String {
    // Simulates POST /api/v1/system/reboot
    "550e8400-e29b-41d4-a716-446655440004".to_string()
}

fn list_jobs_simulated() -> usize {
    // Simulates GET /api/v1/jobs
    25
}

fn get_job_simulated(job_id: &str) -> Option<String> {
    // Simulates GET /api/v1/jobs/{id}
    Some("running".to_string())
}

fn rollback_job_simulated(job_id: &str) -> String {
    // Simulates POST /api/v1/jobs/{id}/rollback
    "550e8400-e29b-41d4-a716-446655440005".to_string()
}

fn delete_job_simulated(job_id: &str) -> String {
    // Simulates DELETE /api/v1/jobs/{id}
    "deleted".to_string()
}

fn websocket_connect_simulated() -> bool {
    // Simulates WS /api/v1/ws/jobs connection
    true
}

fn concurrent_health_checks_simulated(count: usize) -> usize {
    // Simulates concurrent health check requests
    count
}

fn concurrent_package_list_simulated(count: usize) -> usize {
    // Simulates concurrent package list requests
    count * 1500
}

fn concurrent_job_status_simulated(count: usize) -> usize {
    // Simulates concurrent job status requests
    count
}

fn tls_handshake_simulated() -> Duration {
    // Simulates TLS 1.3 mTLS handshake time
    Duration::from_millis(15)
}

fn tls_session_resumption_simulated() -> Duration {
    // Simulates TLS session resumption time
    Duration::from_millis(2)
}

fn json_serialize_simulated() -> String {
    // Simulates JSON serialization
    r#"{"success":true,"request_id":"uuid","timestamp":"2024-01-01T00:00:00Z"}"#.to_string()
}

fn json_deserialize_simulated() -> bool {
    // Simulates JSON deserialization
    true
}

fn job_state_update_simulated() -> bool {
    // Simulates job manager state update
    true
}

// ============================================================================
// Criterion Groups
// ============================================================================

criterion_group!(
    name = benches;
    config = Criterion::default()
        .sample_size(100)
        .noise_threshold(0.05)
        .warm_up_time(Duration::from_secs(2));
    targets = benchmark_endpoint_latency, benchmark_concurrency, benchmark_tls_handshake, benchmark_memory
);

criterion_main!(benches);