use std::{collections::HashMap, io::stdout, time::Duration};

use futures::{future::FutureExt, select, StreamExt};
use futures_timer::Delay;

use crossterm::{
    cursor::position,
    event::{DisableMouseCapture, EnableMouseCapture, Event, EventStream, KeyCode, KeyEvent},
    execute,
    terminal::{disable_raw_mode, enable_raw_mode},
};

async fn set_cutoff(cutoff: f64, freq: f64) -> Result<(), reqwest::Error> {
    // Some simple CLI args requirements...
    let url = format!("http://localhost:3000/cutoff");
    let mut map = HashMap::new();
    map.insert("min_cutoff", cutoff);
    map.insert("max_cutoff", cutoff + 10.0);
    map.insert("freq_hz", freq);
    let client = reqwest::Client::new();
    let res = client.post(url).json(&map).send().await?;

    // eprintln!("Response: {:?} {}", res.version(), res.status());
    // eprintln!("Headers: {:#?}\n", res.headers());

    // let body = res.text().await?;
    // println!("{body}");

    Ok(())
}

const HELP: &str = r#"EventStream based on futures_util::Stream with tokio
 - Keyboard, mouse and terminal resize events enabled
 - Prints "." every second if there's no event
 - Hit "c" to print current cursor position
 - Use Esc to quit
"#;

async fn print_events() {
    let mut reader = EventStream::new();
    let mut cutoff = 30.0;
    let mut last_cutoff = cutoff;
    let mut freq = 1.0;

    loop {
        let mut delay = Delay::new(Duration::from_millis(1_000)).fuse();
        let mut event = reader.next().fuse();
        let mut change = false;
        select! {
            _ = delay => {
            },
            maybe_event = event => {
                match maybe_event {
                    Some(Ok(event)) => {
                        if event == Event::Key(KeyCode::Char('c').into()) {
                            println!("Cursor position: {:?}\r", position());
                        }

                        if event == Event::Key(KeyCode::Esc.into()) {
                            break;
                        }
                        if let Event::Key(k) = event {
                            if let KeyCode::Char(c) = k.code {
                                change = true;
                                match c {
                                    '[' => {
                                        cutoff -= 1.0;
                                    }
                                    ']' => {
                                        cutoff += 1.0;
                                    }
                                    '1' => {
                                        freq *= 0.9;
                                    }
                                    '2' => {
                                        freq *= 1.1;
                                    }
                                    _ => {
                                        change = false;
                                    }
                                }
                            }
                        }
                        if change {
                            set_cutoff(cutoff, freq).await.unwrap();
                            println!("cutoff = {}\r", cutoff);
                        }
                    }
                    Some(Err(e)) => println!("Error: {:?}\r", e),
                    None => break,
                }
            }
        };
    }
}

#[tokio::main]
async fn main() -> std::io::Result<()> {
    println!("{}", HELP);

    enable_raw_mode()?;

    let mut stdout = stdout();
    execute!(stdout, EnableMouseCapture)?;

    print_events().await;

    execute!(stdout, DisableMouseCapture)?;

    disable_raw_mode()
}