use crate::toplevel_subscription::{ToplevelRequest, ToplevelUpdate};
use cctk::{
    sctk::{
        self,
        reexports::client::{protocol::wl_seat::WlSeat, WaylandSource},
        seat::{SeatHandler, SeatState},
    },
    toplevel_info::{ToplevelInfoHandler, ToplevelInfoState},
    toplevel_management::{ToplevelManagerHandler, ToplevelManagerState},
    wayland_client::{self, WEnum},
};
use cosmic_protocols::{
    toplevel_info::v1::client::zcosmic_toplevel_handle_v1,
    toplevel_management::v1::client::zcosmic_toplevel_manager_v1,
};
use futures::channel::mpsc::UnboundedSender;
use sctk::registry::{ProvidesRegistryState, RegistryState};
use wayland_client::{globals::registry_queue_init, Connection, QueueHandle};

struct AppData {
    exit: bool,
    tx: UnboundedSender<ToplevelUpdate>,
    registry_state: RegistryState,
    toplevel_info_state: ToplevelInfoState,
    toplevel_manager_state: ToplevelManagerState,
    seat_state: SeatState,
}

impl ProvidesRegistryState for AppData {
    fn registry(&mut self) -> &mut RegistryState {
        &mut self.registry_state
    }

    sctk::registry_handlers!();
}

impl SeatHandler for AppData {
    fn seat_state(&mut self) -> &mut sctk::seat::SeatState {
        &mut self.seat_state
    }

    fn new_seat(&mut self, _: &Connection, _: &QueueHandle<Self>, _: WlSeat) {}

    fn new_capability(
        &mut self,
        _: &Connection,
        _: &QueueHandle<Self>,
        _: WlSeat,
        _: sctk::seat::Capability,
    ) {
    }

    fn remove_capability(
        &mut self,
        _: &Connection,
        _: &QueueHandle<Self>,
        _: WlSeat,
        _: sctk::seat::Capability,
    ) {
    }

    fn remove_seat(&mut self, _: &Connection, _: &QueueHandle<Self>, _: WlSeat) {}
}

impl ToplevelManagerHandler for AppData {
    fn toplevel_manager_state(&mut self) -> &mut cctk::toplevel_management::ToplevelManagerState {
        &mut self.toplevel_manager_state
    }

    fn capabilities(
        &mut self,
        _: &Connection,
        _: &QueueHandle<Self>,
        _: Vec<WEnum<zcosmic_toplevel_manager_v1::ZcosmicToplelevelManagementCapabilitiesV1>>,
    ) {
        // TODO capabilities could affect the options in the applet
    }
}

impl ToplevelInfoHandler for AppData {
    fn toplevel_info_state(&mut self) -> &mut ToplevelInfoState {
        &mut self.toplevel_info_state
    }

    fn new_toplevel(
        &mut self,
        _conn: &Connection,
        _qh: &QueueHandle<Self>,
        toplevel: &zcosmic_toplevel_handle_v1::ZcosmicToplevelHandleV1,
    ) {
        if let Some(info) = self.toplevel_info_state.info(toplevel) {
            let _ = self
                .tx
                .unbounded_send(ToplevelUpdate::AddToplevel(toplevel.clone(), info.clone()));
        }
    }

    fn update_toplevel(
        &mut self,
        _conn: &Connection,
        _qh: &QueueHandle<Self>,
        toplevel: &zcosmic_toplevel_handle_v1::ZcosmicToplevelHandleV1,
    ) {
        if let Some(info) = self.toplevel_info_state.info(toplevel) {
            let _ = self.tx.unbounded_send(ToplevelUpdate::UpdateToplevel(
                toplevel.clone(),
                info.clone(),
            ));
        }
    }

    fn toplevel_closed(
        &mut self,
        _conn: &Connection,
        _qh: &QueueHandle<Self>,
        toplevel: &zcosmic_toplevel_handle_v1::ZcosmicToplevelHandleV1,
    ) {
        let _ = self
            .tx
            .unbounded_send(ToplevelUpdate::RemoveToplevel(toplevel.clone()));
    }
}

pub(crate) fn toplevel_handler(
    tx: UnboundedSender<ToplevelUpdate>,
    rx: calloop::channel::Channel<ToplevelRequest>,
) {
    let conn = Connection::connect_to_env().unwrap();
    let (globals, event_queue) = registry_queue_init(&conn).unwrap();
    let mut event_loop = calloop::EventLoop::<AppData>::try_new().unwrap();
    let qh = event_queue.handle();
    let wayland_source = WaylandSource::new(event_queue).unwrap();
    let handle = event_loop.handle();

    if handle
        .insert_source(wayland_source, |_, q, state| q.dispatch_pending(state))
        .is_err()
    {
        return;
    };

    if handle
        .insert_source(rx, |event, _, state| match event {
            calloop::channel::Event::Msg(req) => match req {
                ToplevelRequest::Activate(handle, seat) => {
                    let manager = &state.toplevel_manager_state.manager;
                    manager.activate(&handle, &seat);
                }
                ToplevelRequest::Quit(handle) => {
                    let manager = &state.toplevel_manager_state.manager;
                    manager.close(&handle);
                }
                ToplevelRequest::Exit => {
                    state.exit = true;
                }
            },
            calloop::channel::Event::Closed => {
                state.exit = true;
            }
        })
        .is_err()
    {
        return;
    }
    let registry_state = RegistryState::new(&globals);
    let mut app_data = AppData {
        exit: false,
        tx,
        seat_state: SeatState::new(&globals, &qh),
        toplevel_info_state: ToplevelInfoState::new(&registry_state, &qh),
        toplevel_manager_state: ToplevelManagerState::new(&registry_state, &qh),
        registry_state,
    };

    loop {
        if app_data.exit {
            break;
        }
        event_loop.dispatch(None, &mut app_data).unwrap();
    }
}

sctk::delegate_seat!(AppData);
sctk::delegate_registry!(AppData);
cctk::delegate_toplevel_info!(AppData);
cctk::delegate_toplevel_manager!(AppData);