use html5ever::QualName;
use kuchiki::{traits::*, NodeRef};

pub fn rewrite_tags(html: &str, selector: &str, mapping: impl Fn(&NodeRef) -> String) -> String {
    let document = kuchiki::parse_html().one(html);

    for elem in document
        .select(selector)
        .expect("Failed to select document with given selector")
        .collect::<Vec<_>>()
    {
        let node = elem.as_node();
        let new_contents = kuchiki::parse_fragment(
            elem.name.clone(),
            elem.attributes
                .borrow()
                .map
                .clone()
                .into_iter()
                .map(|(name, value)| html5ever::Attribute {
                    name: QualName::new(value.prefix, name.ns, name.local),
                    value: value.value.into(),
                })
                .collect(),
        )
        .one(mapping(node))
        .first_child()
        .expect("Root element somehow missing");

        for child in node.children() {
            child.detach();
        }

        for child in new_contents.children() {
            node.append(child);
        }
    }

    let mut out = Vec::new();
    document
        .serialize(&mut out)
        .expect("Failed to serialize document");
    String::from_utf8_lossy(&out).into_owned()
}

#[cfg(test)]
mod tests {
    use crate::rewrite_tags;

    #[test]
    fn remap_block() {
        let html = r#"<p>hello, world! <span class="replace-me">REPLACE ME</span> <span class="replace-me me-too">me too!</span></p>"#;
        let rewritten_html = rewrite_tags(html, ".replace-me", |_| {
            "<strong>it's a me!</strong>".to_string()
        });

        println!("{}", rewritten_html)
    }
}