cyoa.rs

// Implementation of /Choose Your Own Adventure/
//
// Hal Canary, 2018.
//
// See https://github.com/jcdyer/rust101.git
//
// Data: https://raw.githubusercontent.com/jcdyer/rust101/master/data/adventure.json

extern crate serde;
extern crate serde_json;

#[macro_use]
extern crate serde_derive;

////////////////////////////////////////////////////////////////////////////////

#[derive(Deserialize, Debug)]
struct Action {
    text: String,
    label: String,
    target: usize,
}

#[derive(Deserialize, Debug)]
struct Location {
    id: usize,
    text: String,
    #[serde(default)]
    date: String,
    #[serde(default)]
    actions: Vec<Action>,
}

#[derive(Deserialize, Debug)]
struct Cyoa {
    title: String,
    author: String,
    locations: Vec<Location>,
}

////////////////////////////////////////////////////////////////////////////////
use std::io::Write;

fn main() {
    let path: &str = "adventure.json";
    let file = match std::fs::File::open(path) {
        Ok(f) => f,
        Err(e) => {
            println!("Error opening '{}': {:?}", path, e);
            std::process::exit(1);
        }
    };

    let adventure: Cyoa = match serde_json::from_reader(file) {
        Ok(f) => f,
        Err(e) => {
            println!("Error parsing file '{}': {:?}", path, e);
            std::process::exit(1);
        }
    };

    println!("{}\n{}", adventure.title, adventure.author);
    let locations: &Vec<Location> = &adventure.locations;
    let mut loc_idx: usize = 0;
    loop {
        let loc: &Location = match locations.get(loc_idx) {
            Some(f) => f,
            None => {
                println!("Bad index {}. should be < {}", loc_idx, locations.len());
                std::process::exit(3);
            }
        };
        println!("\n{}\n", loc.text);
        if loc.actions.len() == 0 {
            break;
        }
        for (i, action) in loc.actions.iter().enumerate() {
            println!("  {}. {}", i + 1, action.text);
        }
        let mut choice = String::new();
        print!("\n? ");
        std::io::stdout().flush().expect("");
        std::io::stdin().read_line(&mut choice).expect(
            "Failed to read line",
        );

        let choice_idx = match choice.trim().parse::<usize>() {
            Ok(f) => f,
            Err(_) => {
                if choice == "" {
                    std::process::exit(2);
                }
                println!("Try Again!");
                continue;
            }
        };

        if choice_idx < 1 {
            println!("Try Again!\n");
            continue;
        }
        match loc.actions.get(choice_idx - 1) {
            Some(f) => loc_idx = f.target,
            None => {
                println!("Try Again!\n");
                continue;
            }
        };
    }
}