single_game.ml

(*
 * Glicko2 library. Implements the Glicko2 algorithm.
 * Copyright (C) 2018-present Bruce Ricard
 *
 * This file is part of glicko2.
 *
 * Glicko2 is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * Glicko2 is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Glicko2. If not, see <http://www.gnu.org/licenses/>.
 *)


module Glicko2 = Glicko2.Default.SingleGame

let alice =
  match Glicko2.default_player () with
  | `Ok p -> p
  | `Error _ -> failwith "error creating player"

let bob =
  match Glicko2.default_player ~rating:1800 () with
  | `Ok p -> p
  | `Error _ -> failwith "error creating player"

let charlie =
  match Glicko2.default_player () with
  | `Ok p -> p
  | `Error _ -> failwith "error creating player"

let first_game_result =
  Glicko2.{
          player1 = alice;
          player2 = bob;
          game_outcome = `Player1Win;
  }

let result =
  match Glicko2.rate first_game_result with
  | `Ok r -> r
  | `Error _ -> failwith "deal with error"

let new_alice, new_bob =
  Glicko2.(result.new_player1, result.new_player2)

let second_game_result =
  Glicko2.{
          player1 = new_alice;
          player2 = new_bob;
          game_outcome = `Player2Win;
  }

let result =
  match Glicko2.rate second_game_result with
  | `Ok r -> r
  | `Error _ -> failwith "deal with error"

let new_alice, new_bob =
  Glicko2.(result.new_player1, result.new_player2)

let new_charlie =
  match
    Glicko2.update_player_after_not_player_in_rating_period charlie
  with
  | `Ok p -> p
  | `Error _ -> failwith "deal with error"

(* Those are the players you have at the end *)
let new_players = [new_alice; new_bob; new_charlie]

let new_ratings = List.map (fun p -> p.Glicko2.rating) new_players