use std::io::Read;
use std::str::FromStr;

use xml::attribute::OwnedAttribute;
use xml::reader::{EventReader, XmlEvent};

use super::*;

impl ElementReader for LevelOverride {
    fn read<R: Read>(
        r: &mut EventReader<R>,
        attrs: &[OwnedAttribute],
    ) -> Result<Self, ReaderError> {
        let mut o = LevelOverride::new(usize::from_str(&attrs[0].value)?);
        loop {
            let e = r.next();
            match e {
                Ok(XmlEvent::StartElement {
                    attributes, name, ..
                }) => {
                    let e = XMLElement::from_str(&name.local_name).unwrap();
                    match e {
                        XMLElement::StartOverride => {
                            let val = usize::from_str(&attributes[0].value)?;
                            o = o.start(val);
                            continue;
                        }
                        XMLElement::Level => {
                            let lvl = Level::read(r, &attributes)?;
                            o = o.level(lvl);
                            continue;
                        }
                        _ => {}
                    }
                }
                Ok(XmlEvent::EndElement { name, .. }) => {
                    let e = XMLElement::from_str(&name.local_name).unwrap();
                    if e == XMLElement::LvlOverride {
                        return Ok(o);
                    }
                }
                Err(_) => return Err(ReaderError::XMLReadError),
                _ => {}
            }
        }
    }
}