// mdbook-wordcount, rebuilt against mdbook 0.5.
//
// Iterates every chapter, counts whitespace-separated words, and prints
// per-chapter counts plus a grand total to stdout.
//
// The only reason this exists separately is that the crates.io release is
// compiled against mdbook 0.4, whose RenderContext JSON schema differs from
// 0.5 ("missing field `sections`"). See rust-lang.github.io/mdBook backends.

use mdbook_renderer::book::{BookItem, Chapter};
use mdbook_renderer::RenderContext;
use std::io;

fn main() {
    let mut stdin = io::stdin();
    let ctx = RenderContext::from_json(&mut stdin).expect("couldn't parse RenderContext");

    println!("\n----------");
    println!("Word Count");

    let mut total = 0;
    for item in ctx.book.iter() {
        if let BookItem::Chapter(ref ch) = *item {
            let words = count_words(ch);
            total += words;
            println!("{}: {}", ch.name, words);
        }
    }

    println!("Total: {}", total);
    println!("----------");
}

fn count_words(ch: &Chapter) -> usize {
    ch.content.split_whitespace().count()
}