#![allow(unused)]

mod application;
mod commands;
mod compositor;
mod keymap;
mod ui;

use application::Application;

use std::path::PathBuf;

use anyhow::{Context, Error, Result};

fn setup_logging(logpath: PathBuf, verbosity: u64) -> Result<()> {
    let mut base_config = fern::Dispatch::new();

    // Let's say we depend on something which whose "info" level messages are too
    // verbose to include in end-user output. If we don't need them,
    // let's not include them.
    // .level_for("overly-verbose-target", log::LevelFilter::Warn)

    base_config = match verbosity {
        0 => base_config.level(log::LevelFilter::Warn),
        1 => base_config.level(log::LevelFilter::Info),
        2 => base_config.level(log::LevelFilter::Debug),
        _3_or_more => base_config.level(log::LevelFilter::Trace),
    };

    // Separate file config so we can include year, month and day in file logs
    let file_config = fern::Dispatch::new()
        .format(|out, message, record| {
            out.finish(format_args!(
                "{} {} [{}] {}",
                chrono::Local::now().format("%Y-%m-%dT%H:%M:%S%.3f"),
                record.target(),
                record.level(),
                message
            ))
        })
        .chain(fern::log_file(logpath)?);

    base_config.chain(file_config).apply()?;

    Ok(())
}

pub struct Args {
    display_help: bool,
    display_version: bool,
    verbosity: u64,
    files: Vec<PathBuf>,
}

fn parse_args(mut args: Args) -> Result<Args> {
    let argv: Vec<String> = std::env::args().collect();
    let mut iter = argv.iter();

    iter.next(); // skip the program, we don't care about that

    while let Some(arg) = iter.next() {
        match arg.as_str() {
            "--" => break, // stop parsing at this point treat the remaining as files
            "--version" => args.display_version = true,
            "--help" => args.display_help = true,
            arg if arg.starts_with("--") => {
                return Err(Error::msg(format!(
                    "unexpected double dash argument: {}",
                    arg
                )))
            }
            arg if arg.starts_with('-') => {
                let arg = arg.get(1..).unwrap().chars();
                for chr in arg {
                    match chr {
                        'v' => args.verbosity += 1,
                        'V' => args.display_version = true,
                        'h' => args.display_help = true,
                        _ => return Err(Error::msg(format!("unexpected short arg {}", chr))),
                    }
                }
            }
            arg => args.files.push(PathBuf::from(arg)),
        }
    }

    // push the remaining args, if any to the files
    for filename in iter {
        args.files.push(PathBuf::from(filename));
    }

    Ok(args)
}

#[tokio::main]
async fn main() -> Result<()> {
    let cache_dir = helix_core::cache_dir();
    if !cache_dir.exists() {
        std::fs::create_dir(&cache_dir);
    }

    let logpath = cache_dir.join("helix.log");
    let help = format!(
        "\
{} {}
{}
{}

USAGE:
    hx [FLAGS] [files]...

ARGS:
    <files>...    Sets the input file to use

FLAGS:
    -h, --help       Prints help information
    -v               Increases logging verbosity each use for up to 3 times
                     (default file: {})
    -V, --version    Prints version information
",
        env!("CARGO_PKG_NAME"),
        env!("CARGO_PKG_VERSION"),
        env!("CARGO_PKG_AUTHORS"),
        env!("CARGO_PKG_DESCRIPTION"),
        logpath.display(),
    );

    let mut args: Args = Args {
        display_help: false,
        display_version: false,
        verbosity: 0,
        files: [].to_vec(),
    };

    args = parse_args(args).context("could not parse arguments")?;

    // Help has a higher priority and should be handled separately.
    if args.display_help {
        print!("{}", help);
        std::process::exit(0);
    }

    if args.display_version {
        println!("helix {}", env!("CARGO_PKG_VERSION"));
        std::process::exit(0);
    }

    let conf_dir = helix_core::config_dir();
    if !conf_dir.exists() {
        std::fs::create_dir(&conf_dir);
    }

    setup_logging(logpath, args.verbosity).context("failed to initialize logging")?;

    // TODO: use the thread local executor to spawn the application task separately from the work pool
    let mut app = Application::new(args).context("unable to create new appliction")?;
    app.run().await;

    Ok(())
}