use anyhow::Result;
use byteorder::ByteOrder;
use gauge_mac_tool::GaugeMacCommand;
use gauge_mac_tool::GaugeMacReader;

#[derive(GaugeMacCommand)]
#[reg(0x04)]
struct Foo {
    addr: u16,
    one_byte: u8,
    two_byte: u16,
}

#[derive(GaugeMacCommand)]
struct Bar {
    addr: u16,
}

struct DummyGague {}

impl GaugeMacReader for DummyGague {
    fn fetch_mac_data(&self, addr: u16) -> Result<[u8; 36]> {
        let mut buf = [0u8; 36];
        buf[0] = (addr / 0xff) as u8;
        buf[1] = (addr % 0xff) as u8;
        buf[2] = 0x11_u8;
        buf[3] = 0x12_u8;
        buf[4] = 0x34_u8;

        Ok(buf)
    }
}

#[test]
fn it_works() {
    let gauge = DummyGague {};

    let foo = Foo::build_from_gauge(gauge).unwrap();
    assert_eq!(foo.addr, 0x04);
    assert_eq!(foo.one_byte, 0x11);
    assert_eq!(foo.two_byte, 0x1234);
}

#[test]
fn missing_reg_attribute() {
    let gauge = DummyGague {};

    let bar = Bar::build_from_gauge(gauge).unwrap();
    assert_eq!(bar.addr, 0x0);
}