extern crate rustijvm;

use std::io::{Cursor, Read, Seek, SeekFrom};
use std::sync::{Arc, Mutex};

fn steps(machine: &mut rustijvm::Machine, num: usize) {
    for _ in 0..num {
        machine.step().unwrap();
    }
}

#[test]
fn task4_ldcw1() {
    let mut machine = rustijvm::Machine::new_from_file("files/task4/LoadTest1.ijvm").unwrap();

    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x1));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x3));
}

#[test]
fn task4_simple_load() {
    let mut machine = rustijvm::Machine::new_from_file("files/task4/LoadTest3.ijvm").unwrap();

    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2a));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x1));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2a));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2a));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x3));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2a));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x3));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x1));
    steps(&mut machine, 3);
    assert_eq!(machine.get_tos(), Ok(0x2a));
}

#[test]
fn task4_complex_load() {
    let mut machine = rustijvm::Machine::new_from_file("files/task4/LoadTest2.ijvm").unwrap();

    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2a));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x0));

    steps(&mut machine, 2);
    assert_eq!(machine.get_tos(), Ok(0x3));

    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x2a));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x0));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x3));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x4f));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x3));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x4b));
    steps(&mut machine, 1);
    assert_eq!(machine.get_tos(), Ok(0x3));
}

#[test]
fn task4_iteration_load() {
    let rc = Arc::new(Mutex::new(Cursor::new(Vec::new())));

    let mut machine = rustijvm::Machine::new_from_file("files/task4/LoadTest4.ijvm").unwrap();
    machine.set_output(rc.clone());
    machine.run().unwrap();

    let mut out = rc.lock().unwrap();
    let mut string = String::new();

    out.seek(SeekFrom::Start(0)).unwrap();
    out.read_to_string(&mut string).unwrap();

    assert_eq!(string, "kjihgfedcbaabcd");
}

#[test]
fn task4_iinc() {
    let mut machine = rustijvm::Machine::new_from_file("files/task4/IINCTest.ijvm").unwrap();

    steps(&mut machine, 4);
    assert_eq!(machine.cur_frame().get(0), Ok(0));
    assert_eq!(machine.cur_frame().get(1), Ok(0));

    steps(&mut machine, 1);
    assert_eq!(machine.cur_frame().get(0), Ok(0));
    steps(&mut machine, 1);
    assert_eq!(machine.cur_frame().get(0), Ok(1));
    steps(&mut machine, 1);
    assert_eq!(machine.cur_frame().get(0), Ok(4));

    steps(&mut machine, 1);
    assert_eq!(machine.cur_frame().get(1), Ok(0));
    steps(&mut machine, 1);
    assert_eq!(machine.cur_frame().get(1), Ok(-1));
    steps(&mut machine, 1);
    assert_eq!(machine.cur_frame().get(1), Ok(-4));
}