/* Polydoro - Pomodoro widget for polybar and friends
 * Copyright (C) 2025  Vidhu Kant Sharma <vidhukant@vidhukant.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

use std::os::unix::net::UnixStream;
use std::io::{BufReader};
use std::env;
use bincode::{decode_from_std_read, config};

use crate::daemon::pomo::{Pomo,State};

struct Format {
    format_work: String,
    format_break: String,
    format_long_break: String,

    format_work_paused: String,
    format_break_paused: String,
    format_long_break_paused: String,

    format_work_idle: String,
    format_break_idle: String,
    format_long_break_idle: String,
}

pub fn start_listener() {
    let sock_path = "/tmp/polydorod.sock";
    let stream = UnixStream::connect(sock_path).unwrap_or_else(|_| panic!("could not connect to daemon"));
    let mut reader = BufReader::new(stream);

    let f = Format {
        format_work: get_envvar("FORMAT_WORK", "WORK {counter} - {time}"),
        format_break: get_envvar("FORMAT_BREAK", "BREAK {counter} - {time}"),
        format_long_break: get_envvar("FORMAT_LONG_BREAK", "LONG BREAK {counter} - {time}"),

        format_work_paused: get_envvar("FORMAT_WORK_PAUSED", "[WORK] {counter} - {time}"),
        format_break_paused: get_envvar("FORMAT_BREAK_PAUSED", "[BREAK] {counter} - {time}"),
        format_long_break_paused: get_envvar("FORMAT_LONG_BREAK_PAUSED", "[LONG BREAK] {counter} - {time}"),

        format_work_idle: get_envvar("FORMAT_WORK_IDLE", "(WORK) {counter}"),
        format_break_idle: get_envvar("FORMAT_BREAK_IDLE", "(BREAK) {counter}"),
        format_long_break_idle: get_envvar("FORMAT_LONG_BREAK_IDLE", "(LONG BREAK) {counter}"),
    };

    loop {
        // blocks until a struct is received
        match decode_from_std_read::<Pomo, _, _>(&mut reader, config::standard()) {
            Ok(p) => {
                pretty_print(&f, p);
            }
            Err(e) => {
                eprintln!("polydoro listener error: {}", e);
                std::process::exit(1);
            }
        }
    }
}

// TODO: show remaining time, not time elapsed
fn format_time(secs: u16) -> String {
    format!("{:02}:{:02}", secs / 60, secs % 60)
}

fn get_envvar(key: &str, def: &str) -> String {
    env::var(key).unwrap_or_else(|_| def.to_string())
}

fn pretty_print(f: &Format, p: Pomo) {
    let format = match p.current_state {
        State::Work => &f.format_work,
        State::Break => &f.format_break,
        State::LongBreak => &f.format_long_break,

        State::WorkPaused => &f.format_work_paused,
        State::BreakPaused => &f.format_break_paused,
        State::LongBreakPaused => &f.format_long_break_paused,

        State::WorkIdle => &f.format_work_idle,
        State::BreakIdle => &f.format_break_idle,
        State::LongBreakIdle => &f.format_long_break_idle,
    };


    println!("{}", format
        .replace("{time}", format_time(p.secs_elapsed).as_str())
        .replace("{counter}", format!("{}", p.counter).as_str()));
}