#![feature(path_ext)]
#![allow(dead_code)]

extern crate libc;

use std::fs::{self, File, PathExt};
use std::path::Path;
use std::process::Command;
use std::str::from_utf8;

static PROGNAME: &'static str = "./unlink";

macro_rules! assert_empty_stderr(
    ($cond:expr) => (
        if $cond.stderr.len() > 0 {
            panic!(format!("stderr: {}", $cond.stderr))
        }
    );
);

struct CmdResult {
    success: bool,
    stderr: String,
    stdout: String,
}

fn run(cmd: &mut Command) -> CmdResult {
    let prog = cmd.output().unwrap();
    CmdResult {
        success: prog.status.success(),
        stderr: from_utf8(&prog.stderr).unwrap().to_string(),
        stdout: from_utf8(&prog.stdout).unwrap().to_string(),
    }
}

fn mkdir(dir: &str) {
    fs::create_dir(dir).unwrap();
}

fn touch(file: &str) {
    File::create(file).unwrap();
}

#[test]
fn test_unlink_file() {
    let file = "test_unlink_file";

    touch(file);

    let result = run(Command::new(PROGNAME).arg(file));
    assert_empty_stderr!(result);
    assert!(result.success);

    assert!(!Path::new(file).exists());
}

#[test]
fn test_unlink_multiple_files() {
    let file_a = "test_unlink_multiple_file_a";
    let file_b = "test_unlink_multiple_file_b";

    touch(file_a);
    touch(file_b);

    let result = run(Command::new(PROGNAME).arg(file_a).arg(file_b));
    assert_eq!(result.stderr,
        "unlink: error: extra operand: 'test_unlink_multiple_file_b'\nTry './unlink --help' for more information.\n");
    assert!(!result.success);
}

#[test]
fn test_unlink_directory() {
    let dir = "test_unlink_empty_directory";

    mkdir(dir);

    let result = run(Command::new(PROGNAME).arg(dir));
    assert_eq!(result.stderr,
        "unlink: error: cannot unlink 'test_unlink_empty_directory': Not a regular file or symlink\n");
    assert!(!result.success);
}

#[test]
fn test_unlink_nonexistent() {
    let file = "test_unlink_nonexistent";

    let result = run(Command::new(PROGNAME).arg(file));
    assert_eq!(result.stderr,
        "unlink: error: Cannot stat 'test_unlink_nonexistent': No such file or directory (os error 2)\n");
    assert!(!result.success);
}