coma 0.2.3

Coma is a lightweight command-line tool designed for crawling websites
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use std::{
    collections::HashSet,
    sync::{Arc, Mutex},
};

use markup5ever::local_name;
use scraper::{node::Element, Html};
use url::Url;

use crate::node;

// TODO : add format
pub fn extract_links(url: &Url, page: &Html) -> HashSet<Url> {
    HashSet::from_iter(page.tree.values().filter_map(|v| match v {
        scraper::Node::Element(element) => {
            let element = element.to_owned();

            // Ensure this is a link
            if !matches!(element.name.local, local_name!("a")) {
                return None;
            }

            // We want the attribute "href"
            for (key, value) in &element.attrs {
                if matches!(key.local, local_name!("href")) {
                    return Url::join(url, value).ok();
                }
            }
            None
        }
        _ => None,
    }))
}

pub fn extract_comments(node: &Arc<Mutex<node::Node>>, page: &Html) {
    node.lock().unwrap().comments = Some(
        page.tree
            .values()
            .filter_map(|v| match v {
                scraper::Node::Comment(comment) => {
                    Some(comment.to_string()).filter(|v| !v.is_empty())
                }
                _ => None,
            })
            .collect(),
    );
}

pub fn extract_texts(node: &Arc<Mutex<node::Node>>, page: &Html) {
    node.lock().unwrap().texts = Some(
        page.tree
            .values()
            .filter_map(|v| match v {
                scraper::Node::Text(text) => Some(text.to_string()),
                _ => None,
            })
            .collect(),
    );
}

pub fn extract_element<T, F>(page: &Html, filter: F) -> Vec<T>
where
    F: Fn(Element) -> Option<T>,
{
    page.tree
        .values()
        .filter_map(|v| match v {
            scraper::Node::Element(element) => {
                let element = element.to_owned();
                filter(element)
            }
            _ => None,
        })
        .collect()
}

pub fn extract_images(node: &Arc<Mutex<node::Node>>, page: &Html) {
    node.lock().unwrap().images = Some(extract_element(page, |element: Element| {
        if matches!(element.name.local, local_name!("img")) {
            for (key, value) in &element.attrs {
                if matches!(key.local, local_name!("src")) {
                    // If the url is absolute, the value will replace the base url
                    return Url::join(&node.lock().unwrap().url, value).ok();
                }
            }
        }
        None
    }));
}

// TODO : better rendering
pub fn extract_input(node: &Arc<Mutex<node::Node>>, page: &Html) {
    node.lock().unwrap().inputs = Some(extract_element(page, |element: Element| {
        if matches!(element.name.local, local_name!("input")) {
            Some(format!("{:?}", element))
        } else {
            None
        }
    }));
}