//! Benchmarks for query execution performance
//!
//! Note: These benchmarks simulate query operations.
//! Real query execution benchmarks will be added in Phase 2.

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

/// Benchmark SQL query parsing
fn bench_sql_parsing(c: &mut Criterion) {
    let mut group = c.benchmark_group("sql_parsing");

    for query_type in ["simple", "complex", "subquery"].iter() {
        group.bench_with_input(
            BenchmarkId::from_parameter(query_type),
            query_type,
            |b, &query_type| {
                b.iter(|| {
                    let query = match query_type {
                        "simple" => black_box("SELECT id, name FROM users WHERE id = $1"),
                        "complex" => black_box("SELECT u.id, u.name, p.title FROM users u JOIN posts p ON u.id = p.user_id WHERE u.active = true AND p.published = true ORDER BY p.created_at DESC LIMIT 10"),
                        "subquery" => black_box("SELECT * FROM users WHERE id IN (SELECT user_id FROM posts WHERE published = true GROUP BY user_id HAVING COUNT(*) > 5)"),
                        _ => "",
                    };
                    // Simulate SQL parsing/tokenization
                    let _tokens: Vec<&str> = query.split_whitespace().collect();
                });
            },
        );
    }
    group.finish();
}

/// Benchmark parameter placeholder processing
fn bench_parameter_processing(c: &mut Criterion) {
    let mut group = c.benchmark_group("parameter_processing");

    for param_count in [5, 10, 20, 50].iter() {
        group.bench_with_input(
            BenchmarkId::from_parameter(param_count),
            param_count,
            |b, &param_count| {
                b.iter(|| {
                    // Simulate binding N parameters for prepared statements
                    let mut placeholders = Vec::with_capacity(param_count);
                    for i in 1..=param_count {
                        placeholders.push(format!("${}", i));
                    }
                    let _processed = placeholders.join(", ");
                });
            },
        );
    }
    group.finish();
}

/// Benchmark result set processing
fn bench_result_processing(c: &mut Criterion) {
    let mut group = c.benchmark_group("result_processing");

    for row_count in [100, 1000, 10000].iter() {
        group.bench_with_input(
            BenchmarkId::from_parameter(row_count),
            row_count,
            |b, &row_count| {
                b.iter(|| {
                    // Simulate processing result rows
                    let mut total = 0;
                    for i in 0..row_count {
                        total += i % 100; // Simulate some processing
                    }
                    let _result = total;
                });
            },
        );
    }
    group.finish();
}

/// Benchmark query plan caching simulation
fn bench_query_caching(c: &mut Criterion) {
    c.bench_function("query_plan_caching", |b| {
        b.iter(|| {
            // Simulate query plan lookup/caching
            let query_hash = black_box(0xDEADBEEF_u64);
            let cache_hit = query_hash % 10 != 0; // 90% cache hit rate
            let _plan = if cache_hit {
                "cached_plan"
            } else {
                "computed_plan"
            };
        });
    });
}

criterion_group! {
    name = benches;
    config = Criterion::default()
        .measurement_time(Duration::from_secs(10))
        .sample_size(100);
    targets =
        bench_sql_parsing,
        bench_parameter_processing,
        bench_result_processing,
        bench_query_caching
}

criterion_main!(benches);
