dir.rs

use std::cell::{RefCell, RefMut};
use std::collections::HashMap;
use std::rc::{Rc, Weak};

#[derive(Debug)]
struct File {
    name: String,
    size: usize,
}

#[derive(Debug)]
struct Directory {
    name: String,
    parent: Option<Weak<RefCell<Directory>>>,
    sub_directories: HashMap<String, Rc<RefCell<Directory>>>,
    files: HashMap<String, Rc<File>>,
}

impl Directory {
    fn mkdir(&mut self, name: &str) {
        let dir = Directory {
            name: name.to_string(),
            parent: Some(/* How to initialize this? */),
            sub_directories: HashMap::new(),
            files: HashMap::new(),
        };
        self.sub_directories
            .insert(name.to_string(), Rc::new(RefCell::new(dir)));
    }

    fn mkfile(&mut self, name: &str, size: usize) {
        let file = File {
            name: name.to_string(),
            size,
        };
        self.files.insert(name.to_string(), Rc::new(file));
    }

    fn cd(&mut self, name: &str) -> RefMut<Directory> {
        if name == ".." {
            // TODO: Return parent directory.
        }
        return self.sub_directories[&name.to_string()].borrow_mut();
    }

    fn size(&self) -> usize {
        let mut result = 0;
        for (_, f) in &self.files {
            result += f.size;
        }
        for (_, d) in &self.sub_directories {
            result += d.borrow().size();
        }
        result
    }

    fn all_sizes(&self) -> Vec<usize> {
        let mut result = Vec::new();
        result.push(self.size());
        for (_, d) in &self.sub_directories {
            result.extend(d.borrow().all_sizes());
        }
        result
    }
}