use std::env;
use std::process::Command;
use std::str;

static PROGNAME: &'static str = "./readlink";
static GIBBERISH: &'static str = "supercalifragilisticexpialidocious";

fn current_directory() -> String {
    env::current_dir().unwrap().into_os_string().into_string().unwrap()
}

fn repeat_str(s: &str, n: u32) -> String {
    let mut repeated = String::new();
    for _ in 0 .. n {
        repeated.push_str(s);
    }
    repeated
}

#[test]
fn test_canonicalize() {
    let po = Command::new(PROGNAME)
        .arg("-f")
        .arg(".")
        .output()
        .unwrap_or_else(|err| panic!("{}", err));

    let out = str::from_utf8(&po.stdout[..]).unwrap().trim_right();
    assert_eq!(out, current_directory());
}

#[test]
fn test_canonicalize_existing() {
    let po = Command::new(PROGNAME)
        .arg("-e")
        .arg(".")
        .output()
        .unwrap_or_else(|err| panic!("{}", err));

    let out = str::from_utf8(&po.stdout[..]).unwrap().trim_right();
    assert_eq!(out, current_directory());
}

#[test]
fn test_canonicalize_missing() {
    let mut expected = current_directory();
    expected.push_str("/");
    expected.push_str(GIBBERISH);

    let po = Command::new(PROGNAME)
        .arg("-m")
        .arg(GIBBERISH)
        .output()
        .unwrap_or_else(|err| panic!("{}", err));

    let out = str::from_utf8(&po.stdout[..]).unwrap().trim_right();
    assert_eq!(out, expected);
}

#[test]
fn test_long_redirection_to_current_dir() {
    // Create a 256-character path to current directory
    let dir = repeat_str("./", 128);
    let po = Command::new(PROGNAME)
        .arg("-n")
        .arg("-m")
        .arg(dir)
        .output()
        .unwrap_or_else(|err| panic!("{}", err));

    let out = str::from_utf8(&po.stdout[..]).unwrap();
    assert_eq!(out, current_directory());
}

#[test]
fn test_long_redirection_to_root() {
    // Create a 255-character path to root
    let dir = repeat_str("../", 85);
    let po = Command::new(PROGNAME)
        .arg("-n")
        .arg("-m")
        .arg(dir)
        .output()
        .unwrap_or_else(|err| panic!("{}", err));

    let out = str::from_utf8(&po.stdout[..]).unwrap();
    assert_eq!(out, "/");
}