use std::fs::File;
use rosu_pp::{Beatmap, BeatmapExt};

let file = match File::open("/path/to/file.osu") {
    Ok(file) => file,
    Err(why) => panic!("Could not open file: {}", why),
};

// Parse the map yourself
let map = match Beatmap::parse(file) {
    Ok(map) => map,
    Err(why) => panic!("Error while parsing map: {}", why),
};

// If `BeatmapExt` is included, you can make use of
// some methods on `Beatmap` to make your life simpler.
// However, to calculate specific pp values, it is recommended
// to match on the map's mode yourself and modify the mode's
// pp calculator, e.g. `TaikoPP`, manually.
let result = map.pp()
    .mods(24) // HDHR
    .combo(1234)
    .misses(2)
    .accuracy(99.2)
    .calculate();

println!("PP: {}", result.pp());

// If you intend to reuse the current map-mod combination,
// make use of the previous result!
// If attributes are given, then stars & co don't have to be recalculated.
let next_result = map.pp()
    .mods(24) // HDHR
    .attributes(result) // recycle
    .combo(543)
    .misses(5)
    .n50(3)
    .passed_objects(600)
    .accuracy(96.5)
    .calculate();

println!("Next PP: {}", next_result.pp());

let stars = map.stars(16, None).stars(); // HR
let max_pp = map.max_pp(16).pp();

println!("Stars: {} | Max PP: {}", stars, max_pp);

With async

Need to enable async_std in Cargo.toml to use async parsing Beatmap::parse_async.

use async_std::fs::File;

// Async read the map
let file = match File::open("/path/to/file.osu").await {
    Ok(file) => file,
    Err(why) => panic!("Could not open file: {}", why),
};

// Async Parse the map
let map = match Beatmap::parse_async(file).await {
    Ok(map) => map,
    Err(why) => panic!("Error while parsing map: {}", why),
};

let result = map.pp()
    .mods(24) // HDHR
    .combo(1234)
    .misses(2)
    .accuracy(99.2)
    .calculate_async().await;

println!("PP: {}", result.pp());

osu!standard versions

all_included: Both stack leniency & slider paths are considered so that the difficulty and pp calculation immitates osu! as close as possible. Pro: Most precise; Con: Least performant.
no_leniency: The positional offset of notes created by stack leniency is not considered. This means the jump distance inbetween notes might be slightly off, resulting in small inaccuracies. Since calculating these offsets is relatively expensive though, this version is considerably faster than all_included.
no_slider_no_leniency (i.e. oppai): In addition to not considering the positional offset caused by stack leniency, slider paths are also ignored. This means the travel distance of notes is completely omitted which may cause further inaccuracies. Since the slider paths don't have to be computed though, it is generally faster than no_leniency.

Note: If the fruits feature is enabled, sliders will be parsed regardless, resulting in a reduced performance advantage of no_sliders_no_leniency.

Features

Flag	Description
`default`	Enable all modes and choose the `no_leniency` version for osu!standard.
`taiko`	Enable osu!taiko.
`fruits`	Enable osu!ctb.
`mania`	Enable osu!mania.
`osu`	Enable osu!standard. Requires to also enable exactly one of the features `no_leniency`, `no_sliders_no_leniency`, or `all_included`.
`no_leniency`	When calculating difficulty attributes in osu!standard, ignore stack leniency but consider sliders. Solid middleground between performance and precision, hence the default version.
`no_sliders_no_leniency`	When calculating difficulty attributes in osu!standard, ignore stack leniency and sliders. Best performance but slightly less precision than `no_leniency`.
`all_included`	When calculating difficulty attributes in osu!standard, consider both stack leniency and sliders. Best precision but significantly worse performance than `no_leniency`.
`async_std`	Enable async beatmap parsing with `async-std`

Roadmap

osu sr versions
- [x] all included
- [x] no_leniency
- [x] no_sliders_no_leniency
[x] taiko sr
[x] ctb sr
[x] mania sr

[x] osu pp
[x] taiko pp
[x] ctb pp
[x] mania pp

[x] refactoring
[x] benchmarking