use crate::{db::bots::Bot, DbPool}; use crate::db; use crate::modules::matches::RunMatch; use rand::seq::SliceRandom; use std::time::Duration; use tokio; const RANKER_INTERVAL: u64 = 60; const START_RATING: f64 = 0.0; const SCALE: f64 = 100.0; const MAX_UPDATE: f64 = 5.0; pub async fn run_ranker(db_pool: DbPool) { // TODO: make this configurable // play at most one match every n seconds let mut interval = tokio::time::interval(Duration::from_secs(RANKER_INTERVAL)); let db_conn = db_pool .get() .await .expect("could not get database connection"); loop { interval.tick().await; let bots = db::bots::find_all_bots(&db_conn).unwrap(); if bots.len() < 2 { // not enough bots to play a match continue; } let selected_bots: Vec = { let mut rng = &mut rand::thread_rng(); bots.choose_multiple(&mut rng, 2).cloned().collect() }; play_ranking_match(selected_bots, db_pool.clone()).await; } } async fn play_ranking_match(selected_bots: Vec, db_pool: DbPool) { let db_conn = db_pool.get().await.expect("could not get db pool"); let mut code_bundles = Vec::new(); for bot in &selected_bots { let code_bundle = db::bots::active_code_bundle(bot.id, &db_conn) .expect("could not get active code bundle"); code_bundles.push(code_bundle); } let code_bundle_refs = code_bundles.iter().map(|b| b).collect::>(); let mut run_match = RunMatch::from_players(code_bundle_refs); run_match .store_in_database(&db_conn) .expect("could not store match in db"); let outcome = run_match .spawn(db_pool.clone()) .await .expect("running match failed"); let mut ratings = Vec::new(); for bot in &selected_bots { let rating = db::ratings::get_rating(bot.id, &db_conn) .expect("could not get bot rating") .unwrap_or(START_RATING); ratings.push(rating); } // simple elo rating let scores = match outcome.winner { None => vec![0.5; 2], Some(player_num) => { // TODO: please get rid of this offset let player_ix = player_num - 1; let mut scores = vec![0.0; 2]; scores[player_ix] = 1.0; scores } }; for i in 0..2 { let j = 1 - i; let scaled_difference = (ratings[i] - ratings[j]) / SCALE; let expected = 1.0 / (1.0 + 10f64.powf(scaled_difference)); let new_rating = ratings[i] + MAX_UPDATE * (scores[i] - expected); db::ratings::set_rating(selected_bots[i].id, new_rating, &db_conn) .expect("could not update bot rating"); } }