use dbus::arg;
use dbus::blocking::stdintf::org_freedesktop_dbus::PropertiesPropertiesChanged;
use dbus::blocking::Connection;
use dbus::message::Message;
use std::collections::HashMap;
use std::process::Command;
use std::sync::{Arc, Mutex};
use std::time::Duration;

// Custom signal type impl
// Mostly copied from library examples
#[derive(Debug)]
pub struct ComJacobCasperMailUnreadCount {
    pub count: u32,
}

impl arg::AppendAll for ComJacobCasperMailUnreadCount {
    fn append(&self, iter: &mut arg::IterAppend) {
        arg::RefArg::append(&self.count, iter);
    }
}

impl arg::ReadAll for ComJacobCasperMailUnreadCount {
    fn read(iter: &mut arg::Iter) -> Result<Self, arg::TypeMismatchError> {
        Ok(ComJacobCasperMailUnreadCount {
            count: iter.read()?,
        })
    }
}

impl dbus::message::SignalArgs for ComJacobCasperMailUnreadCount {
    const NAME: &'static str = "UnreadCount";
    const INTERFACE: &'static str = "com.jacobcasper.Mail";
}

fn update_map(arc_map: Arc<Mutex<HashMap<String, String>>>, key: &str, val: &str) {
    let clone_arc = arc_map.clone();
    let mut map = clone_arc.lock().unwrap();
    map.insert(String::from(key), String::from(val));
    let _ = Command::new("xsetroot")
        .arg("-name")
        .arg(format!(
            "[🔊 {title} - {artist}] | ✉ {unread_count}",
            title = map.get("title").unwrap_or(&String::from("")),
            artist = map.get("artist").unwrap_or(&String::from("")),
            unread_count = map.get("unread_count").unwrap_or(&String::from("?")),
        ))
        .spawn();
}

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let arc_locked_xset_map = Arc::new(Mutex::new(HashMap::new()));
    let conn = Connection::new_session()?;

    let mail_proxy = conn.with_proxy(
        "com.jacobcasper.Mail",
        "/com/jacobcasper/Mail/Unread",
        Duration::from_millis(5000),
    );

    let mail_match_map = arc_locked_xset_map.clone();
    let _ = mail_proxy.match_signal(
        move |m: ComJacobCasperMailUnreadCount, _: &Connection, _: &Message| {
            update_map(
                mail_match_map.clone(),
                "unread_count",
                m.count.to_string().as_str(),
            );
            true
        },
    );

    let spotify_proxy = conn.with_proxy(
        "org.mpris.MediaPlayer2.spotify",
        "/org/mpris/MediaPlayer2",
        Duration::from_millis(5000),
    );

    let spotify_match_map = arc_locked_xset_map.clone();
    let _ = spotify_proxy.match_signal(
        move |pc: PropertiesPropertiesChanged, _: &Connection, _: &Message| {
            pc.changed_properties["Metadata"]
                .0
                .as_iter()
                .and_then(|mut iter| {
                    // Iterating over a RefArg goes key, value, key, value... Insane honestly.
                    while let Some(key) = iter.next() {
                        let key_str = key.as_str()?;
                        let value = iter.next();

                        match key_str {
                            "xesam:artist" => {
                                // Variant holding a variant that should just be a Vec<&str> I
                                // believe. This is _the recommended_ way to do this by the author.
                                let inner_value = value?.as_iter()?.next()?.as_iter()?.next()?;
                                let artist = inner_value.as_str()?;
                                update_map(spotify_match_map.clone(), "artist", artist);
                            }
                            "xesam:title" => {
                                let title = value?.as_iter()?.next()?.as_str()?;
                                update_map(spotify_match_map.clone(), "title", title);
                            }
                            _ => (),
                        }
                    }
                    Some(())
                });
            true
        },
    );

    loop {
        conn.process(Duration::from_millis(1000))?;
    }
}