use rand::prelude::*;

/*
rust port of:
https://gist.github.com/sagebind/8358734
^ was the first result of "simple c++ game"
port by nullflex
*/

fn create_zombie() -> u8 {
    let mut rng = thread_rng();

    let chance = rng.gen_range(0, 100);
    if chance > 75 {
        return 11;
    }

    return rng.gen_range(1, 10);
}

#[allow(non_camel_case_types)]
struct player_info {
    skill: u8,
    score: u16,
    name: String
}

#[allow(non_camel_case_types)]
struct zombie_info {
    count: u16,
    killed: u16
}

fn main() {
    use std::io::stdin;

    // game stats
    let rand_player_skill: u8 = {
        let mut rng = thread_rng();
        rng.gen_range(2, 12)
    };

    let mut player = player_info{skill: rand_player_skill, score: 1, name: String::from("")};
    let mut zombie_stats = zombie_info{count: 0, killed: 0};

    let mut input_value: String = String::from("");
    // title
    println!("Welcome to Zombie War (rust port). \nPress [ENTER] to start.");
    stdin().read_line(&mut input_value).expect("how did you break the first input prompt?");

    // player name
    println!("Enter your name: ");
    stdin().read_line(&mut player.name).expect("something invalid passed in name input");
    player.name = player.name.trim_end().to_string();

    // ask how many zombies
    println!("How many zombies do you want to fight? ");
    {
        let mut zombie_count_str: String = String::from("");
        stdin().read_line(&mut zombie_count_str).expect("something invalid passed in zombies fight input");
        zombie_count_str = zombie_count_str.trim_end().to_string();
        zombie_stats.count = zombie_count_str.parse::<u16>().expect("invalid number entered in zombies fight");
    }

    println!("Get ready to fight {}!", player.name);

    // main game loop
    while zombie_stats.killed < zombie_stats.count {
        // create a random zombie
        let zombie_skill: u8 = create_zombie();

        // battle sequence
        if zombie_skill > 10 {
            println!("boss zombie alert!");
        }
        else {
            println!("here comes zombie {}", zombie_stats.killed);
        }

        println!("fighting...");
        std::thread::sleep(std::time::Duration::from_secs(2));

        // zombie killed the player
        if player.skill < zombie_skill {
            println!("you have died.");
            break;
        }

        let skill_delta: i8 = (player.skill - zombie_skill) as i8;

        if skill_delta > 7 {
            println!("you wasted the zombie");
            player.score *= 2;
        }
        else if skill_delta > 5 {
            println!("you decapitated the zombie");
            player.score *= 2;
        }
        else if skill_delta > 0 {
            println!("you killed the zombie");
            player.score *= 2;
        }
        else {
            println!("you killed the zombie, but suffered injuries");
        }

        zombie_stats.killed += 1;
        println!("hit enter to continue.");
        stdin().read_line(&mut input_value).expect("how did you break an input that doesn't even require anything?");
    }

    // game ended
    if zombie_stats.killed == zombie_stats.count {
        println!("you survived");
    }
    else {
        println!("you did not survive");
    }

    println!("zombies killed: {}, final score: {}", zombie_stats.killed, player.score);
}