use std::env::args;

use log::info;
use rsbag::{Bag, Result};

fn main() -> Result<()> {
    color_eyre::install()?;
    env_logger::init();

    let args: Vec<_> = args().collect();
    if args.len() != 2 {
        eprintln!("Usage: {} <bag path>", args[0]);
        return Ok(());
    }

    let bag_path = &args[1];
    let mut bag = Bag::open(bag_path)?;
    let chunk_positions = bag
        .index()
        .chunks
        .iter()
        .map(|chunk| chunk.pos)
        .collect::<Vec<_>>();
    let chunk_sizes = chunk_positions
        .windows(2)
        .map(|window| {
            if let &[last, next] = window {
                next - last
            } else {
                unreachable!();
            }
        })
        .collect::<Vec<_>>();
    let mean_chunk_size =
        chunk_sizes.iter().map(|s| *s as f64).sum::<f64>() / (chunk_sizes.len() as f64);
    info!("average chunk size: {}", mean_chunk_size);

    let info = bag.compute_info()?;
    info!("bag info: {:#?}", info);

    Ok(())
}