//! Throwaway probe: what are a music bank's sub-waves, decoded and timed?
//!
//! `export_bgm` sums every sub-wave `media` returns and scales by 1/n. If one of
//! them is not music, the divisor is wrong and every real stem is attenuated for
//! nothing -- the same defect already found and fixed in `export_voice`.
use std::process::Command;
use sylpheed_formats::media;

fn main() {
    let disc =
        std::env::var("SYLPHEED_DISC").expect("set SYLPHEED_DISC to the extracted disc root");
    let src = media::DirectorySource::new(&disc);
    for bank in ["BGM_103.slb", "BGM_102.slb", "BGM_001.slb"] {
        match media::sound_bank_riffs(&src, bank) {
            Ok(riffs) => {
                println!("{bank}: {} sub-wave(s)", riffs.len());
                for (i, r) in riffs.iter().enumerate() {
                    let p = std::env::temp_dir().join(format!("bk_{i}.xma.wav"));
                    std::fs::write(&p, r).unwrap();
                    let w = std::env::temp_dir().join(format!("bk_{i}.wav"));
                    let _ = Command::new("ffmpeg")
                        .args(["-hide_banner", "-loglevel", "error", "-y", "-i"])
                        .arg(&p)
                        .arg(&w)
                        .output();
                    let out = Command::new("ffmpeg")
                        .args(["-hide_banner", "-v", "info", "-i"])
                        .arg(&w)
                        .args(["-af", "astats=measure_perchannel=none", "-f", "null", "-"])
                        .output()
                        .unwrap();
                    let t = String::from_utf8_lossy(&out.stderr).into_owned();
                    let get = |k: &str| {
                        t.lines()
                            .find_map(|l| l.split_once(k).map(|x| x.1.trim().to_string()))
                            .unwrap_or_else(|| "?".into())
                    };
                    let dur = Command::new("ffprobe")
                        .args([
                            "-v",
                            "error",
                            "-show_entries",
                            "format=duration",
                            "-of",
                            "csv=p=0",
                        ])
                        .arg(&w)
                        .output()
                        .ok()
                        .map(|o| String::from_utf8_lossy(&o.stdout).trim().to_string())
                        .unwrap_or_default();
                    println!(
                        "   sub-wave {i}: {:>9} B  ->  {:>10} s   peak {:>10}   rms {}",
                        r.len(),
                        dur,
                        get("Peak level dB:"),
                        get("RMS level dB:")
                    );
                    let _ = std::fs::remove_file(&p);
                    let _ = std::fs::remove_file(&w);
                }
            }
            Err(e) => println!("{bank}: {e}"),
        }
    }
}