// Comprehensive latency benchmarks for RuVector Nervous System components
// Measures P50, P99, P99.9 percentiles for all critical operations

use criterion::{black_box, criterion_group, criterion_main, BenchmarkId, Criterion, Throughput};
use rand::rngs::StdRng;
use rand::{Rng, SeedableRng};
use std::time::Duration;

// Note: Import actual types when implemented
// use ruvector_nervous_system::*;

// ============================================================================
// Event Bus Benchmarks
// ============================================================================

fn benchmark_event_bus(c: &mut Criterion) {
    let mut group = c.benchmark_group("event_bus");
    group.warm_up_time(Duration::from_secs(1));
    group.measurement_time(Duration::from_secs(5));

    // Event publish latency (target: <10μs)
    group.bench_function("event_publish", |b| {
        // let bus = EventBus::new(1000);
        // let event = Event::new("test", vec![0.0; 128]);
        b.iter(|| {
            // bus.publish(black_box(event.clone()))
            // Placeholder until EventBus is implemented
            black_box(42);
        });
    });

    // Event delivery from bounded queue (target: <5μs)
    group.bench_function("bounded_queue_delivery", |b| {
        // let queue = BoundedQueue::new(1000);
        b.iter(|| {
            // queue.pop()
            black_box(42);
        });
    });

    // Priority routing (target: <20μs)
    group.bench_function("priority_routing", |b| {
        // let router = PriorityRouter::new();
        // let event = Event::with_priority("test", vec![0.0; 128], Priority::High);
        b.iter(|| {
            // router.route(black_box(&event))
            black_box(42);
        });
    });

    group.finish();
}

// ============================================================================
// HDC (Hyperdimensional Computing) Benchmarks
// ============================================================================

fn benchmark_hdc(c: &mut Criterion) {
    let mut group = c.benchmark_group("hdc");
    group.warm_up_time(Duration::from_millis(500));

    let mut rng = StdRng::seed_from_u64(42);

    // Vector binding (target: <100ns)
    let vec_a = generate_bitvector(&mut rng, 10000);
    let vec_b = generate_bitvector(&mut rng, 10000);
    group.bench_function("vector_binding", |bencher| {
        bencher.iter(|| xor_bitvectors(black_box(&vec_a), black_box(&vec_b)));
    });

    // Vector bundling (target: <500ns)
    let bundle_vectors: Vec<_> = (0..10)
        .map(|_| generate_bitvector(&mut rng, 10000))
        .collect();
    group.bench_function("vector_bundling", |bencher| {
        bencher.iter(|| majority_bitvectors(black_box(&bundle_vectors)));
    });

    // Hamming distance (target: <100ns)
    let ham_a = generate_bitvector(&mut rng, 10000);
    let ham_b = generate_bitvector(&mut rng, 10000);
    group.bench_function("hamming_distance", |bencher| {
        bencher.iter(|| hamming_distance(black_box(&ham_a), black_box(&ham_b)));
    });

    // Similarity check (target: <200ns)
    let sim_a = generate_bitvector(&mut rng, 10000);
    let sim_b = generate_bitvector(&mut rng, 10000);
    group.bench_function("similarity_check", |bencher| {
        bencher.iter(|| hdc_similarity(black_box(&sim_a), black_box(&sim_b)));
    });

    group.finish();
}

// ============================================================================
// WTA (Winner-Take-All) Benchmarks
// ============================================================================

fn benchmark_wta(c: &mut Criterion) {
    let mut group = c.benchmark_group("wta");

    let mut rng = StdRng::seed_from_u64(42);

    // Single winner selection (target: <1μs)
    group.bench_function("single_winner", |b| {
        let inputs: Vec<f32> = (0..1000).map(|_| rng.gen()).collect();

        b.iter(|| {
            // wta.select_winner(black_box(&inputs))
            argmax(black_box(&inputs))
        });
    });

    // k-WTA with k=5 (target: <5μs)
    group.bench_function("k_wta_5", |b| {
        let inputs: Vec<f32> = (0..1000).map(|_| rng.gen()).collect();

        b.iter(|| {
            // wta.select_k_winners(black_box(&inputs), 5)
            argmax_k(black_box(&inputs), 5)
        });
    });

    // Lateral inhibition update (target: <10μs)
    group.bench_function("lateral_inhibition", |b| {
        let inputs: Vec<f32> = (0..1000).map(|_| rng.gen()).collect();

        b.iter(|| {
            // lateral_inhibition.update(black_box(&inputs))
            apply_inhibition(black_box(&inputs), 0.5)
        });
    });

    group.finish();
}

// ============================================================================
// Hopfield Network Benchmarks
// ============================================================================

fn benchmark_hopfield(c: &mut Criterion) {
    let mut group = c.benchmark_group("hopfield");
    group.warm_up_time(Duration::from_secs(1));
    group.measurement_time(Duration::from_secs(5));

    let mut rng = StdRng::seed_from_u64(42);

    // Pattern retrieval with varying pattern counts
    for num_patterns in [10, 100, 1000].iter() {
        group.bench_with_input(
            BenchmarkId::new("pattern_retrieval", num_patterns),
            num_patterns,
            |b, &num_patterns| {
                // let hopfield = ModernHopfield::new(512, 100.0);
                // for _ in 0..num_patterns {
                //     hopfield.store(generate_random_vector(&mut rng, 512));
                // }
                let query = generate_random_vector(&mut rng, 512);

                b.iter(|| {
                    // hopfield.retrieve(black_box(&query))
                    // Placeholder
                    black_box(query.clone())
                });
            },
        );
    }

    // Pattern storage (target: <100μs)
    group.bench_function("pattern_storage", |b| {
        // let hopfield = ModernHopfield::new(512, 100.0);
        let pattern = generate_random_vector(&mut rng, 512);

        b.iter(|| {
            // hopfield.store(black_box(pattern.clone()))
            black_box(42);
        });
    });

    // Energy computation (target: <50μs)
    group.bench_function("energy_computation", |b| {
        // let hopfield = ModernHopfield::new(512, 100.0);
        let state = generate_random_vector(&mut rng, 512);

        b.iter(|| {
            // hopfield.energy(black_box(&state))
            compute_energy_placeholder(black_box(&state))
        });
    });

    group.finish();
}

// ============================================================================
// Pattern Separation Benchmarks
// ============================================================================

fn benchmark_pattern_separation(c: &mut Criterion) {
    let mut group = c.benchmark_group("pattern_separation");

    let mut rng = StdRng::seed_from_u64(42);

    // Encoding with orthogonalization (target: <500μs)
    group.bench_function("orthogonal_encoding", |b| {
        // let encoder = PatternSeparator::new(512);
        let input = generate_random_vector(&mut rng, 512);

        b.iter(|| {
            // encoder.encode(black_box(&input))
            orthogonalize_placeholder(black_box(&input))
        });
    });

    // Collision detection (target: <100μs)
    group.bench_function("collision_detection", |b| {
        let encoded = generate_random_vector(&mut rng, 512);

        b.iter(|| {
            // detector.check_collision(black_box(&encoded))
            black_box(false)
        });
    });

    // Decorrelation (target: <200μs)
    group.bench_function("decorrelation", |b| {
        let input = generate_random_vector(&mut rng, 512);

        b.iter(|| {
            // decorrelator.decorrelate(black_box(&input))
            decorrelate_placeholder(black_box(&input))
        });
    });

    group.finish();
}

// ============================================================================
// Plasticity Benchmarks
// ============================================================================

fn benchmark_plasticity(c: &mut Criterion) {
    let mut group = c.benchmark_group("plasticity");

    let mut rng = StdRng::seed_from_u64(42);

    // E-prop gradient update (target: <100μs)
    group.bench_function("eprop_gradient_update", |b| {
        // let eprop = EPropLearner::new(100, 0.01);
        let gradient = generate_random_vector(&mut rng, 100);

        b.iter(|| {
            // eprop.update_gradients(black_box(&gradient))
            black_box(42);
        });
    });

    // BTSP eligibility trace (target: <50μs)
    group.bench_function("btsp_eligibility_trace", |b| {
        // let btsp = BTSPLearner::new(100, 0.01, 1000);

        b.iter(|| {
            // btsp.update_eligibility(black_box(0.5))
            black_box(42);
        });
    });

    // EWC Fisher matrix update (target: <1ms)
    group.bench_function("ewc_fisher_update", |b| {
        // let ewc = EWCLearner::new(1000);
        let gradient = generate_random_vector(&mut rng, 1000);

        b.iter(|| {
            // ewc.update_fisher(black_box(&gradient))
            black_box(42);
        });
    });

    group.finish();
}

// ============================================================================
// Cognitum Integration Benchmarks
// ============================================================================

fn benchmark_cognitum(c: &mut Criterion) {
    let mut group = c.benchmark_group("cognitum");

    // Reflex event→action (target: <100μs)
    group.bench_function("reflex_latency", |b| {
        // let reflex = ReflexArc::new();
        // let event = Event::new("sensor", vec![0.5; 128]);

        b.iter(|| {
            // reflex.process(black_box(&event))
            black_box(42);
        });
    });

    // v0 adapter dispatch (target: <50μs)
    group.bench_function("v0_adapter_dispatch", |b| {
        // let adapter = V0Adapter::new();

        b.iter(|| {
            // adapter.dispatch(black_box(&event))
            black_box(42);
        });
    });

    group.finish();
}

// ============================================================================
// Helper Functions (Placeholders)
// ============================================================================

fn generate_bitvector(rng: &mut StdRng, size: usize) -> Vec<u64> {
    (0..(size + 63) / 64).map(|_| rng.gen()).collect()
}

fn generate_random_vector(rng: &mut StdRng, size: usize) -> Vec<f32> {
    (0..size).map(|_| rng.gen()).collect()
}

fn xor_bitvectors(a: &[u64], b: &[u64]) -> Vec<u64> {
    a.iter().zip(b.iter()).map(|(x, y)| x ^ y).collect()
}

fn majority_bitvectors(vectors: &[Vec<u64>]) -> Vec<u64> {
    let len = vectors[0].len();
    (0..len)
        .map(|i| vectors.iter().map(|v| v[i]).fold(0u64, |acc, x| acc ^ x))
        .collect()
}

fn hamming_distance(a: &[u64], b: &[u64]) -> u32 {
    a.iter()
        .zip(b.iter())
        .map(|(x, y)| (x ^ y).count_ones())
        .sum()
}

fn hdc_similarity(a: &[u64], b: &[u64]) -> f32 {
    let total_bits = a.len() * 64;
    let hamming = hamming_distance(a, b) as f32;
    1.0 - (hamming / total_bits as f32)
}

fn argmax(inputs: &[f32]) -> usize {
    inputs
        .iter()
        .enumerate()
        .max_by(|(_, a), (_, b)| a.partial_cmp(b).unwrap())
        .unwrap()
        .0
}

fn argmax_k(inputs: &[f32], k: usize) -> Vec<usize> {
    let mut indexed: Vec<_> = inputs.iter().enumerate().collect();
    indexed.sort_by(|(_, a), (_, b)| b.partial_cmp(a).unwrap());
    indexed.iter().take(k).map(|(i, _)| *i).collect()
}

fn apply_inhibition(inputs: &[f32], strength: f32) -> Vec<f32> {
    let max_val = inputs.iter().cloned().fold(f32::NEG_INFINITY, f32::max);
    inputs
        .iter()
        .map(|&x| (x - strength * max_val).max(0.0))
        .collect()
}

fn compute_energy_placeholder(state: &[f32]) -> f32 {
    -state.iter().map(|x| x * x).sum::<f32>()
}

fn orthogonalize_placeholder(input: &[f32]) -> Vec<f32> {
    let norm: f32 = input.iter().map(|x| x * x).sum::<f32>().sqrt();
    input.iter().map(|x| x / norm).collect()
}

fn decorrelate_placeholder(input: &[f32]) -> Vec<f32> {
    let mean: f32 = input.iter().sum::<f32>() / input.len() as f32;
    input.iter().map(|x| x - mean).collect()
}

// ============================================================================
// Criterion Configuration
// ============================================================================

criterion_group!(
    benches,
    benchmark_event_bus,
    benchmark_hdc,
    benchmark_wta,
    benchmark_hopfield,
    benchmark_pattern_separation,
    benchmark_plasticity,
    benchmark_cognitum,
);

criterion_main!(benches);