use std::borrow::Cow;
use std::io::BufRead;
use quick_xml::escape::resolve_predefined_entity;
use quick_xml::events::attributes::Attribute;
use quick_xml::events::Event;
use quick_xml::name::QName;
use quick_xml::Reader;
use crate::error::Error;
pub(crate) fn decode<'s, B: BufRead>(
bytes: &'s [u8],
reader: &Reader<B>,
) -> Result<Cow<'s, str>, Error> {
let text = reader.decoder().decode(bytes)?;
Ok(text)
}
pub(crate) fn attr_value<'s, B: BufRead>(
attr: &'s Attribute<'s>,
reader: &Reader<B>,
) -> Result<Cow<'s, str>, Error> {
let value = attr.decode_and_unescape_value(reader.decoder())?;
Ok(value)
}
pub(crate) fn skip<B: BufRead>(end: QName<'_>, reader: &mut Reader<B>) -> Result<(), Error> {
reader.read_to_end_into(end, &mut Vec::new())?;
Ok(())
}
pub fn element_text<R: BufRead>(reader: &mut Reader<R>) -> Result<Option<String>, Error> {
let mut content = String::new();
let mut buf = Vec::new();
loop {
match reader.read_event_into(&mut buf)? {
Event::Start(element) => {
skip(element.name(), reader)?;
}
Event::Text(element) => {
let decoded = element.decode()?;
content.push_str(decoded.as_ref());
}
Event::GeneralRef(gref) => {
let entity = gref.decode()?;
if let Some(resolved_entity) = resolve_predefined_entity(&entity) {
content.push_str(resolved_entity);
} else if let Some(ch) = gref.resolve_char_ref()? {
content.push(ch);
} else {
content.push('&');
content.push_str(&entity);
content.push(';');
}
}
Event::CData(element) => {
content.push_str(decode(&element, reader)?.as_ref());
}
Event::End(_) | Event::Eof => break,
_ => {}
}
buf.clear();
}
Ok(Some(content.trim().to_owned()).filter(|c| !c.is_empty()))
}