use clap::{arg, App};
use evdev::{AttributeSet, Device, Key};
use nix::unistd::{Group, Uid};
use std::{
    env, io::prelude::*, os::unix::net::UnixStream, path::Path, process::exit, thread::sleep,
    time::Duration,
};

mod config;

pub fn main() {
    let args = set_flags().get_matches();
    env::set_var("RUST_LOG", "swhkd=warn");

    if args.is_present("debug") {
        env::set_var("RUST_LOG", "swhkd=trace");
    }

    env_logger::init();
    log::trace!("Logger initialized.");
    permission_check();

    let config_file_path: std::path::PathBuf;
    if args.is_present("config") {
        config_file_path = Path::new(args.value_of("config").unwrap()).to_path_buf();
    } else {
        config_file_path = check_config_xdg();
    }
    log::debug!("Using config file path: {:#?}", config_file_path);

    if !config_file_path.exists() {
        log::error!("{:#?} doesn't exist", config_file_path);
        exit(1);
    }

    log::trace!("Attempting to find all keyboard file descriptors.");
    let mut keyboard_devices: Vec<Device> = Vec::new();
    for (_, device) in evdev::enumerate().enumerate() {
        if check_keyboard(&device) {
            keyboard_devices.push(device);
        }
    }

    if keyboard_devices.is_empty() {
        log::error!("No valid keyboard device was detected!");
        exit(1);
    }
    log::debug!("{} Keyboard device(s) detected.", keyboard_devices.len());

    let hotkeys = match config::load(config_file_path) {
        Err(..) => {
            log::error!("Error: failed to parse config file.");
            exit(1);
        }
        Ok(out) => out,
    };

    for hotkey in &hotkeys {
        log::debug!("hotkey: {:#?}", hotkey);
    }

    if let Err(e) = sock_send("notify-send hello world") {
        log::error!("Failed to send command over IPC.");
        log::error!("Is swhks running?");
        log::error!("{:#?}", e)
    };

    let mut key_states: Vec<AttributeSet<Key>> = Vec::new();
    let mut possible_hotkeys: Vec<config::Hotkey> = Vec::new();
    loop {
        for device in &keyboard_devices {
            key_states.push(device.get_key_state().unwrap());
        }

        for state in &key_states {
            for hotkey in &hotkeys {
                if state.iter().count() == hotkey.modifiers.len() + 1 {
                    // +1 Because we handle only 1 keysym.
                    possible_hotkeys.push(hotkey.clone());
                }
            }
        }

        log::debug!("{:#?}", possible_hotkeys);
        key_states.clear();
        possible_hotkeys.clear();
        sleep(Duration::from_millis(10)); // without this, swhkd will start to chew through your cpu.
    }
}
pub fn permission_check() {
    if !Uid::current().is_root() {
        let groups = nix::unistd::getgroups();
        for (_, groups) in groups.iter().enumerate() {
            for group in groups {
                let group = Group::from_gid(*group);
                if group.unwrap().unwrap().name == "input" {
                    log::error!("Note: INVOKING USER IS IN INPUT GROUP!!!!");
                    log::error!("THIS IS A HUGE SECURITY RISK!!!!");
                }
            }
        }
        log::error!("Consider using `pkexec swhkd ...`");
        exit(1);
    } else {
        log::warn!("Running swhkd as root!");
    }
}

pub fn check_keyboard(device: &Device) -> bool {
    if device.supported_keys().map_or(false, |keys| keys.contains(Key::KEY_ENTER)) {
        log::debug!("{} is a keyboard.", device.name().unwrap(),);
        true
    } else {
        log::trace!("{} is not a keyboard.", device.name().unwrap(),);
        false
    }
}

pub fn set_flags() -> App<'static> {
    let app = App::new("swhkd")
        .version(env!("CARGO_PKG_VERSION"))
        .author(env!("CARGO_PKG_AUTHORS"))
        .about("Simple Wayland HotKey Daemon")
        .arg(
            arg!(-c --config <CONFIG_FILE_PATH>)
                .required(false)
                .help("Set a custom config file path"),
        )
        .arg(arg!(-d - -debug).required(false).help("Enable debug mode"));
    app
}

pub fn check_config_xdg() -> std::path::PathBuf {
    let config_file_path: std::path::PathBuf;
    match env::var("XDG_CONFIG_HOME") {
        Ok(val) => {
            config_file_path = Path::new(&val).join("swhkd/swhkdrc");
            log::debug!("XDG_CONFIG_HOME exists: {:#?}", val);
            return config_file_path;
        }
        Err(_) => {
            log::error!("XDG_CONFIG_HOME has not been set.");
            config_file_path = Path::new("/etc/swhkd/swhkdrc").to_path_buf();
            log::warn!(
                "Note: Due to the design of the application, the invoking user is always root."
            );
            log::warn!("You can set a custom config file with the -c option.");
            log::warn!("Adding your user to the input group could solve this.");
            log::warn!("However that's a massive security flaw and basically defeats the purpose of using wayland.");
            log::warn!("The following issue may be addressed in the future, but it is certainly not a priority right now.");
        }
    }
    config_file_path
}

fn sock_send(command: &str) -> std::io::Result<()> {
    let mut stream = UnixStream::connect("/tmp/swhkd.sock")?;
    stream.write_all(command.as_bytes())?;
    Ok(())
}