use std::fs::File;
use std::io::{BufReader, Read};

use criterion::{criterion_group, criterion_main, Criterion};
use flate2::bufread::GzDecoder;
use lhef::{Reader, Writer};

fn criterion_benchmark(c: &mut Criterion) {
    let file = File::open("test_data/2j.lhe.gz").expect("file not found");
    let mut reader = GzDecoder::new(BufReader::new(file));
    let mut event_txt = Vec::new();
    reader.read_to_end(&mut event_txt).unwrap();
    let event_txt = event_txt;
    c.bench_function("read", |b| {
        b.iter(|| {
            let reader = BufReader::new(event_txt.as_slice());
            let mut lhef = Reader::new(reader).unwrap();
            let mut nevents = 0;
            while let Ok(Some(_)) = lhef.hepeup() {
                nevents += 1
            }
            assert_eq!(nevents, 1628);
        })
    });

    let mut events = Vec::new();
    let reader = BufReader::new(event_txt.as_slice());
    let mut lhef = Reader::new(reader).unwrap();
    while let Ok(Some(event)) = lhef.hepeup() {
        events.push(event)
    }
    c.bench_function("write", |b| {
        b.iter(|| {
            let mut writer =
                Writer::new(std::io::sink(), lhef.version()).unwrap();
            writer.header(lhef.header()).unwrap();
            if let Some(xml_header) = lhef.xml_header() {
                writer.xml_header(xml_header).unwrap();
            }
            writer.heprup(lhef.heprup()).unwrap();
            for event in &events {
                writer.hepeup(event).unwrap();
            }
            writer.finish().unwrap();
        })
    });
}

criterion_group!(benches, criterion_benchmark);
criterion_main!(benches);