day02.rs

use super::*;

enum Figure {
    Rock,
    Paper,
    Scissor,
}

enum GameResult {
    Win,
    Loose,
    Draw,
}

struct Game {
    player1: Figure,
    player2: Figure,
    result: GameResult,
}

fn points_for_result(r: GameResult) -> i32 {
    match r {
        GameResult::Win => 6,
        GameResult::Draw => 3,
        GameResult::Loose => 0,
    }
}

fn points_for_figure(f: Figure) -> i32 {
    match f {
        Figure::Scissor => 3,
        Figure::Rock => 1,
        Figure::Paper => 2,
    }
}
impl Game {
    fn new(player1: char, player2: char) -> Game {
        Game {
            player1: match player1 {
                'Y' => Figure::Paper,
                'X' => Figure::Rock,
                'Z' => Figure::Scissor,
                a => panic!("invalid: {}", a),
            },
            player2: match player2 {
                'A' => Figure::Rock,
                'B' => Figure::Paper,
                'C' => Figure::Scissor,
                _ => panic!("invalid"),
            },
            result: match player1 {
                'Y' => GameResult::Draw,
                'X' => GameResult::Loose,
                'Z' => GameResult::Win,
                a => panic!("invalid: {}", a),
            },
        }
    }

    fn points(&self) -> i32 {
        let mut sum: i32 = 0;
        match self.player1 {
            Figure::Paper => {
                sum += points_for_figure(Figure::Paper);
                match self.player2 {
                    Figure::Paper => sum += points_for_result(GameResult::Draw),
                    Figure::Scissor => sum += points_for_result(GameResult::Loose),
                    Figure::Rock => sum += points_for_result(GameResult::Win),
                }
            }
            Figure::Rock => {
                sum += points_for_figure(Figure::Rock);
                match self.player2 {
                    Figure::Rock => sum += points_for_result(GameResult::Draw),
                    Figure::Scissor => sum += points_for_result(GameResult::Win),
                    Figure::Paper => sum += points_for_result(GameResult::Loose),
                }
            }
            Figure::Scissor => {
                sum += points_for_figure(Figure::Scissor);
                match self.player2 {
                    Figure::Scissor => sum += points_for_result(GameResult::Draw),
                    Figure::Paper => sum += points_for_result(GameResult::Win),
                    Figure::Rock => sum += points_for_result(GameResult::Loose),
                }
            }
        }
        sum
    }

    fn points2(&self) -> i32 {
        let mut sum: i32 = 0;
        match self.result {
            GameResult::Draw => {
                sum += points_for_result(GameResult::Draw);
                match self.player2 {
                    Figure::Paper => sum += points_for_figure(Figure::Paper),
                    Figure::Scissor => sum += points_for_figure(Figure::Scissor),
                    Figure::Rock => sum += points_for_figure(Figure::Rock),
                }
            }
            GameResult::Win => {
                sum += points_for_result(GameResult::Win);
                match self.player2 {
                    Figure::Rock => sum += points_for_figure(Figure::Paper),
                    Figure::Scissor => sum += points_for_figure(Figure::Rock),
                    Figure::Paper => sum += points_for_figure(Figure::Scissor),
                }
            }
            GameResult::Loose => {
                sum += points_for_result(GameResult::Loose);
                match self.player2 {
                    Figure::Scissor => sum += points_for_figure(Figure::Paper),
                    Figure::Paper => sum += points_for_figure(Figure::Rock),
                    Figure::Rock => sum += points_for_figure(Figure::Scissor),
                }
            }
        }
        sum
    }
}

pub fn day02(filename: String) {
    if let Ok(lines) = read_lines(&filename) {
        // Consumes the iterator, returns an (Optional) String
        let mut sum: i32 = 0;
        let mut sum2: i32 = 0;
        for line in lines {
            if let Ok(ip) = line {
                let player2 = ip.chars().nth(0).unwrap();
                let player1 = ip.chars().nth(2).unwrap();
                let game = Game::new(player1, player2);
                sum += game.points();
                sum2 += game.points2();
            }
        }
        println!("{}, {}", sum, sum2)
    }
}