mdbook-compress 0.2.0

use std::collections::{BTreeMap, HashSet};
use anyhow::Error;
use genpdf::elements::{LinearLayout, Paragraph};
use genpdf::style::{Color, Style};
use crate::highlight::util::{StyleElement, to_block};

/// Checks if the used highlight_.js script can highlight a specific language. Used before calling
/// [highlight] to check that the Js won't fail because it can't highlight the language
fn check_language(names: HashSet<String>, hl: &String) -> Option<String> {
	for name in names {
		if name.starts_with("language-") {
			match std::process::Command::new("node")
				.arg("-e")
				.arg(format!("{};console.log(!!hljs.getLanguage({:?}))", hl, &name[9..name.len()]))
				.output() {
				Ok(out) => {
					let stdout = String::from_utf8(out.stdout).unwrap();
					if out.status.code() != Some(0) {
						println!("Error in getting highlight_.js languages! {}", String::from_utf8(out.stderr).unwrap());
						std::process::exit(1)
					}
					if stdout.trim() == "true" { return Some(name[9..name.len()].to_string()) }
				}
				Err(e) => {
					mdbook::utils::log_backtrace(&Error::new(e));
					std::process::exit(1)
				}
			}
		}
	}
	None
}

/// Highlights a section of code using highlight_.js
pub fn highlight(classes: HashSet<String>, hl: &String, src: String) -> LinearLayout {
	if let Some(lang_name) = check_language(classes, hl) {
		let raw = match std::process::Command::new("node")
			.current_dir(std::env::current_dir().unwrap())
			.args([
				"-e",
				&*format!(
					"{};console.log(hljs.highlight('{}',{{language:'{}'}}).value)", hl,
					src.replace("'", "\\'").replace("\"", "\\\"").replace("\n", "\\n"), lang_name
				)
			]).output() {
			Ok(out) => {
				let stdout = String::from_utf8(out.stdout).unwrap();
				if out.status.code() != Some(0) {
					println!("Error highlighting code! Using un-highlighted code. {}", String::from_utf8(out.stderr).unwrap());
					src.to_string()
				} else { stdout }
			}
			Err(e) => {
				mdbook::utils::log_backtrace(&Error::new(e));
				std::process::exit(1)
			}
		};
		let colour_map = StyleElement::Parent {default: Style::new(), children: BTreeMap::from_iter([
			("comment", Color::Greyscale(87)),
			("quote", Color::Greyscale(87)),
			("variable", Color::Rgb(215, 0, 37)),
			("template-variable", Color::Rgb(215, 0, 37)),
			("tag", Color::Rgb(215, 0, 37)),
			("attribute", Color::Rgb(215, 0, 37)),
			("name", Color::Rgb(215, 0, 37)),
			("regexp", Color::Rgb(215, 0, 37)),
			("link", Color::Rgb(215, 0, 37)),
			("name", Color::Rgb(215, 0, 37)),
			("selector-id", Color::Rgb(215, 0, 37)),
			("selector-class", Color::Rgb(215, 0, 37)),
			("number", Color::Rgb(178, 30, 0)),
			("meta", Color::Rgb(178, 30, 0)),
			("built_in", Color::Rgb(178, 30, 0)),
			("builtin-name", Color::Rgb(178, 30, 0)),
			("literal", Color::Rgb(178, 30, 0)),
			("type", Color::Rgb(178, 30, 0)),
			("params", Color::Rgb(178, 30, 0)),
			("string", Color::Rgb(0, 130, 0)),
			("symbol", Color::Rgb(0, 130, 0)),
			("bullet", Color::Rgb(0, 130, 0)),
			("title", Color::Rgb(0, 48, 242)),
			("section", Color::Rgb(0, 48, 242)),
			("keyword", Color::Rgb(157, 0, 236)),
			("selector-tag", Color::Rgb(157, 0, 236)),
			("addition", Color::Rgb(34, 134, 58)),
			("deletion", Color::Rgb(179, 29, 40))
		].map(|(n, c)| (n.to_string(), StyleElement::Child(Style::new().with_color(c)))))};
		to_block(raw, colour_map, |t| {
			let mut iter = t.split_whitespace().enumerate();
			let mut out = Vec::new();
			if let Some((_, f)) = iter.next() {
				out.push(f[5..f.len()].to_string())
			}
			for (l, f) in iter {
				out.push(f[..f.len() - l].to_string())
			}
			out
		})
	} else {
		let mut block = LinearLayout::vertical();
		for line in src.lines() {
			block.push(Paragraph::new(line))
		}
		block
	}
}