mod rope;
mod tiocgwinsz;

use rope::Rope;
use std::ffi::{OsStr, OsString};
use std::path::Path;

fn edit(file: &OsStr) -> Result<(), String> {
    let r = match Rope::open(Path::new(file)) {
        Ok(r) => r,
        Err(err) => {
            return Err(format!("open file {}: {}", file.to_string_lossy(), err));
        }
    };
    let size = match tiocgwinsz::size() {
        Some(size) => size,
        None => {
            return Err(String::from("cannot get terminal size"));
        }
    };
    let mut stdout = std::io::stdout();
    if let Err(err) = r.print_lines(&mut stdout, 0, usize::from(size.ws_row)) {
        return Err(format!("write: {}", err));
    }
    return Ok(());
}

fn main() {
    let args: Vec<OsString> = std::env::args_os().collect();
    if args.len() != 2 {
        println!("Usage: edit <filename>");
        std::process::exit(1);
    }
    if let Err(err) = edit(&args[1]) {
        println!("FAIL: {}", err);
        std::process::exit(1);
    }
}