use anyhow::Result;
use std::env;
use std::fs::create_dir_all;
use std::str::FromStr;
use log::debug;

pub fn setup_logger() -> Result<()> {
    let log_file = env::var("LOG_FILE").or_else(|_| {
        create_dir_all("logs/")?;

        anyhow::Ok(format!(
            "logs/{}_{}.log",
            env!("CARGO_PKG_NAME"),
            chrono::Local::now().format("%Y%m%d_%H%M%S")
        ))
    })?;
    let log_level = match env::var("LOG_LEVEL") {
        Ok(log_level) => log::LevelFilter::from_str(&log_level).unwrap_or(log::LevelFilter::Info),
        Err(_) => log::LevelFilter::Info,
    };

    fern::Dispatch::new()
        .format(|out, message, record| {
            out.finish(format_args!(
                "[{}][{}][{}] {}",
                chrono::Local::now().format("%Y-%m-%d %H:%M:%S"),
                record.target(),
                record.level(),
                message
            ))
        })
        .chain(
            fern::Dispatch::new()
                .level(log_level)
                .chain(std::io::stdout()),
        )
        .chain(fern::log_file(log_file.clone())?)
        .apply()?;

    debug!("Logging to {} at level {}", log_file, log_level);
    Ok(())
}