pinnacle/src/state.rs

// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at https://mozilla.org/MPL/2.0/.
//
// SPDX-License-Identifier: MPL-2.0

use std::{
    cell::RefCell,
    error::Error,
    ffi::OsString,
    os::{fd::AsRawFd, unix::net::UnixStream},
    path::Path,
    process::Stdio,
    sync::{Arc, Mutex},
};

use crate::{
    api::{
        msg::{Args, CallbackId, Msg, OutgoingMsg, Request, RequestResponse},
        PinnacleSocketSource,
    },
    focus::FocusState,
    grab::resize_grab::ResizeSurfaceState,
    tag::Tag,
    window::window_state::WindowResizeState,
};
use calloop::futures::Scheduler;
use futures_lite::AsyncBufReadExt;
use smithay::{
    backend::renderer::element::RenderElementStates,
    desktop::{
        utils::{
            surface_presentation_feedback_flags_from_states, surface_primary_scanout_output,
            OutputPresentationFeedback,
        },
        PopupManager, Space, Window,
    },
    input::{keyboard::XkbConfig, pointer::CursorImageStatus, Seat, SeatState},
    output::Output,
    reexports::{
        calloop::{
            self, channel::Event, generic::Generic, Interest, LoopHandle, LoopSignal, Mode,
            PostAction,
        },
        wayland_server::{
            backend::{ClientData, ClientId, DisconnectReason},
            protocol::wl_surface::WlSurface,
            Display,
        },
    },
    utils::{Clock, Logical, Monotonic, Point},
    wayland::{
        compositor::{self, CompositorClientState, CompositorState},
        data_device::DataDeviceState,
        dmabuf::DmabufFeedback,
        fractional_scale::FractionalScaleManagerState,
        output::OutputManagerState,
        shell::xdg::{XdgShellState, XdgToplevelSurfaceData},
        shm::ShmState,
        socket::ListeningSocketSource,
        viewporter::ViewporterState,
    },
};

use crate::{backend::Backend, input::InputState};

/// The main state of the application.
pub struct State<B: Backend> {
    pub backend_data: B,

    pub loop_signal: LoopSignal,
    pub loop_handle: LoopHandle<'static, CalloopData<B>>,
    pub clock: Clock<Monotonic>,

    pub space: Space<Window>,
    pub move_mode: bool,
    pub socket_name: String,

    pub seat: Seat<State<B>>,

    pub compositor_state: CompositorState,
    pub data_device_state: DataDeviceState,
    pub seat_state: SeatState<Self>,
    pub shm_state: ShmState,
    pub output_manager_state: OutputManagerState,
    pub xdg_shell_state: XdgShellState,
    pub viewporter_state: ViewporterState,
    pub fractional_scale_manager_state: FractionalScaleManagerState,
    pub input_state: InputState,
    pub api_state: ApiState,
    pub focus_state: FocusState,

    pub popup_manager: PopupManager,

    pub cursor_status: CursorImageStatus,
    pub pointer_location: Point<f64, Logical>,
    pub windows: Vec<Window>,

    pub async_scheduler: Scheduler<()>,

    // TODO: move into own struct
    // |     basically just clean this mess up
    pub output_callback_ids: Vec<CallbackId>,
}

impl<B: Backend> State<B> {
    pub fn handle_msg(&mut self, msg: Msg) {
        // tracing::debug!("Got {msg:?}");
        match msg {
            Msg::SetKeybind {
                key,
                modifiers,
                callback_id,
            } => {
                tracing::info!("set keybind: {:?}, {}", modifiers, key);
                self.input_state
                    .keybinds
                    .insert((modifiers.into(), key), callback_id);
            }
            Msg::SetMousebind { button: _ } => todo!(),
            Msg::CloseWindow { window_id } => {
                if let Some(window) = window_id.window(self) {
                    window.toplevel().send_close();
                }
            }
            Msg::ToggleFloating { window_id } => {
                if let Some(window) = window_id.window(self) {
                    crate::window::toggle_floating(self, &window);
                }
            }

            Msg::Spawn {
                command,
                callback_id,
            } => {
                self.handle_spawn(command, callback_id);
            }

            Msg::SetWindowSize {
                window_id,
                width,
                height,
            } => {
                let Some(window) = window_id.window(self) else { return };

                // TODO: tiled vs floating
                let window_size = window.geometry().size;
                window.toplevel().with_pending_state(|state| {
                    // INFO: calling window.geometry() in with_pending_state
                    // |     will hang the compositor
                    state.size = Some(
                        (
                            width.unwrap_or(window_size.w),
                            height.unwrap_or(window_size.h),
                        )
                            .into(),
                    );
                });
                window.toplevel().send_pending_configure();
            }
            Msg::MoveWindowToTag { window_id, tag_id } => {
                if let Some(window) = window_id.window(self) {
                    window.with_state(|state| {
                        self.focus_state
                            .focused_output
                            .as_ref()
                            .unwrap()
                            .with_state(|op_state| {
                                let tag = op_state.tags.iter().find(|tag| tag.name() == tag_id);
                                if let Some(tag) = tag {
                                    state.tags = vec![tag.clone()];
                                }
                            });
                    });
                    let output = self.focus_state.focused_output.clone().unwrap();
                    self.re_layout(&output);
                }
            }
            Msg::ToggleTagOnWindow { window_id, tag_id } => {
                if let Some(window) = window_id.window(self) {
                    window.with_state(|state| {
                        self.focus_state
                            .focused_output
                            .as_ref()
                            .unwrap()
                            .with_state(|op_state| {
                                let tag = op_state.tags.iter().find(|tag| tag.name() == tag_id);
                                if let Some(tag) = tag {
                                    if state.tags.contains(tag) {
                                        state.tags.retain(|tg| tg != tag);
                                    } else {
                                        state.tags.push(tag.clone());
                                    }
                                }
                            });
                    });

                    let output = self.focus_state.focused_output.clone().unwrap();
                    self.re_layout(&output);
                }
            }
            Msg::ToggleTag {
                output_name,
                tag_name,
            } => {
                tracing::debug!("ToggleTag");

                let output = self
                    .space
                    .outputs()
                    .find(|op| op.name() == output_name)
                    .cloned();
                if let Some(output) = output {
                    output.with_state(|state| {
                        if let Some(tag) = state.tags.iter_mut().find(|tag| tag.name() == tag_name)
                        {
                            tracing::debug!("Setting tag {tag:?} to {}", !tag.active());
                            tag.set_active(!tag.active());
                        }
                    });
                    self.re_layout(&output);
                }
            }
            Msg::SwitchToTag {
                output_name,
                tag_name,
            } => {
                let output = self
                    .space
                    .outputs()
                    .find(|op| op.name() == output_name)
                    .cloned();
                if let Some(output) = output {
                    output.with_state(|state| {
                        if !state.tags.iter().any(|tag| tag.name() == tag_name) {
                            // TODO: notify error
                            return;
                        }
                        for tag in state.tags.iter_mut() {
                            tag.set_active(false);
                        }

                        let Some(tag) = state
                            .tags
                            .iter_mut()
                            .find(|tag| tag.name() == tag_name)
                        else {
                            unreachable!()
                        };
                        tag.set_active(true);

                        tracing::debug!(
                            "focused tags: {:?}",
                            state
                                .tags
                                .iter()
                                .filter(|tag| tag.active())
                                .map(|tag| tag.name())
                                .collect::<Vec<_>>()
                        );
                    });
                    self.re_layout(&output);
                }
            }
            // TODO: add output
            Msg::AddTags {
                output_name,
                tag_names,
            } => {
                if let Some(output) = self
                    .space
                    .outputs()
                    .find(|output| output.name() == output_name)
                {
                    output.with_state(|state| {
                        state.tags.extend(tag_names.iter().cloned().map(Tag::new));
                        tracing::debug!("tags added, are now {:?}", state.tags);
                    });
                }
            }
            Msg::RemoveTags {
                output_name,
                tag_names,
            } => {
                if let Some(output) = self
                    .space
                    .outputs()
                    .find(|output| output.name() == output_name)
                {
                    output.with_state(|state| {
                        state.tags.retain(|tag| !tag_names.contains(&tag.name()));
                    });
                }
            }
            Msg::SetLayout {
                output_name,
                tag_name,
                layout,
            } => {
                let output = self
                    .space
                    .outputs()
                    .find(|op| op.name() == output_name)
                    .cloned();
                if let Some(output) = output {
                    output.with_state(|state| {
                        if let Some(tag) = state.tags.iter_mut().find(|tag| tag.name() == tag_name)
                        {
                            tag.set_layout(layout);
                        }
                    });
                    self.re_layout(&output);
                }
            }

            Msg::ConnectForAllOutputs { callback_id } => {
                let stream = self
                    .api_state
                    .stream
                    .as_ref()
                    .expect("Stream doesn't exist");
                let mut stream = stream.lock().expect("Couldn't lock stream");
                for output in self.space.outputs() {
                    crate::api::send_to_client(
                        &mut stream,
                        &OutgoingMsg::CallCallback {
                            callback_id,
                            args: Some(Args::ConnectForAllOutputs {
                                output_name: output.name(),
                            }),
                        },
                    )
                    .expect("Send to client failed");
                }
                self.output_callback_ids.push(callback_id);
            }

            Msg::Quit => {
                self.loop_signal.stop();
            }

            Msg::Request(request) => {
                self.handle_request(request);
            }
        }
    }

    fn handle_request(&mut self, request: Request) {
        let stream = self
            .api_state
            .stream
            .as_ref()
            .expect("Stream doesn't exist");
        let mut stream = stream.lock().expect("Couldn't lock stream");
        match request {
            Request::GetWindows => {
                let window_ids = self
                    .windows
                    .iter()
                    .map(|win| win.with_state(|state| state.id))
                    .collect::<Vec<_>>();

                // FIXME: figure out what to do if error
                crate::api::send_to_client(
                    &mut stream,
                    &OutgoingMsg::RequestResponse {
                        response: RequestResponse::Windows { window_ids },
                    },
                )
                .expect("Couldn't send to client");
            }
            Request::GetWindowProps { window_id } => {
                let window = window_id.window(self);
                let size = window
                    .as_ref()
                    .map(|win| (win.geometry().size.w, win.geometry().size.h));
                let loc = window
                    .as_ref()
                    .and_then(|win| self.space.element_location(win))
                    .map(|loc| (loc.x, loc.y));
                let (class, title) = window.as_ref().map_or((None, None), |win| {
                    compositor::with_states(win.toplevel().wl_surface(), |states| {
                        let lock = states
                            .data_map
                            .get::<XdgToplevelSurfaceData>()
                            .expect("XdgToplevelSurfaceData wasn't in surface's data map")
                            .lock()
                            .expect("failed to acquire lock");
                        (lock.app_id.clone(), lock.title.clone())
                    })
                });
                let floating = window
                    .as_ref()
                    .map(|win| win.with_state(|state| state.floating.is_floating()));
                let focused = window.as_ref().and_then(|win| {
                    self.focus_state
                        .current_focus() // TODO: actual focus
                        .map(|foc_win| win == &foc_win)
                });
                crate::api::send_to_client(
                    &mut stream,
                    &OutgoingMsg::RequestResponse {
                        response: RequestResponse::WindowProps {
                            size,
                            loc,
                            class,
                            title,
                            floating,
                            focused,
                        },
                    },
                )
                .expect("failed to send to client");
            }
            Request::GetOutputs => {
                let output_names = self
                    .space
                    .outputs()
                    .map(|output| output.name())
                    .collect::<Vec<_>>();
                crate::api::send_to_client(
                    &mut stream,
                    &OutgoingMsg::RequestResponse {
                        response: RequestResponse::Outputs { output_names },
                    },
                )
                .expect("failed to send to client");
            }
            Request::GetOutputProps { output_name } => {
                let output = self
                    .space
                    .outputs()
                    .find(|output| output.name() == output_name);
                let res = output.as_ref().and_then(|output| {
                    output.current_mode().map(|mode| (mode.size.w, mode.size.h))
                });
                let refresh_rate = output
                    .as_ref()
                    .and_then(|output| output.current_mode().map(|mode| mode.refresh));
                let model = output
                    .as_ref()
                    .map(|output| output.physical_properties().model);
                let physical_size = output.as_ref().map(|output| {
                    (
                        output.physical_properties().size.w,
                        output.physical_properties().size.h,
                    )
                });
                let make = output
                    .as_ref()
                    .map(|output| output.physical_properties().make);
                let loc = output
                    .as_ref()
                    .map(|output| (output.current_location().x, output.current_location().y));
                let focused = self
                    .focus_state
                    .focused_output
                    .as_ref()
                    .and_then(|foc_op| output.map(|op| op == foc_op));
                let tag_ids = output.as_ref().map(|output| {
                    output.with_state(|state| {
                        state.tags.iter().map(|tag| tag.id()).collect::<Vec<_>>()
                    })
                });
                crate::api::send_to_client(
                    &mut stream,
                    &OutgoingMsg::RequestResponse {
                        response: RequestResponse::OutputProps {
                            make,
                            model,
                            loc,
                            res,
                            refresh_rate,
                            physical_size,
                            focused,
                            tag_ids,
                        },
                    },
                )
                .expect("failed to send to client");
            }
            Request::GetTags => {
                let tag_ids = self
                    .space
                    .outputs()
                    .flat_map(|op| op.with_state(|state| state.tags.clone()))
                    .map(|tag| tag.id())
                    .collect::<Vec<_>>();
                crate::api::send_to_client(
                    &mut stream,
                    &OutgoingMsg::RequestResponse {
                        response: RequestResponse::Tags { tag_ids },
                    },
                )
                .expect("failed to send to client");
            }
            Request::GetTagProps { tag_id } => {
                let tag = tag_id.tag(self);
                let output_name = tag
                    .as_ref()
                    .and_then(|tag| tag.output(self))
                    .map(|output| output.name());
                let active = tag.as_ref().map(|tag| tag.active());
                let name = tag.as_ref().map(|tag| tag.name());
                crate::api::send_to_client(
                    &mut stream,
                    &OutgoingMsg::RequestResponse {
                        response: RequestResponse::TagProps {
                            active,
                            name,
                            output_name,
                        },
                    },
                )
                .expect("failed to send to client");
            }
        }
    }

    pub fn handle_spawn(&self, command: Vec<String>, callback_id: Option<CallbackId>) {
        let mut command = command.into_iter();
        let Some(program) = command.next() else {
            // TODO: notify that command was nothing
            return;
        };

        let program = OsString::from(program);
        let Ok(mut child) = async_process::Command::new(&program)
            .env("WAYLAND_DISPLAY", self.socket_name.clone())
            .stdin(if callback_id.is_some() {
                Stdio::piped()
            } else {
                // piping to null because foot won't open without a callback_id
                // otherwise
                Stdio::null()
            })
            .stdout(if callback_id.is_some() {
                Stdio::piped()
            } else {
                Stdio::null()
            })
            .stderr(if callback_id.is_some() {
                Stdio::piped()
            } else {
                Stdio::null()
            })
            .args(command)
            .spawn()
        else {
            // TODO: notify user that program doesn't exist
            tracing::warn!("tried to run {}, but it doesn't exist", program.to_string_lossy());
            return;
        };

        if let Some(callback_id) = callback_id {
            let stdout = child.stdout.take();
            let stderr = child.stderr.take();
            let stream_out = self
                .api_state
                .stream
                .as_ref()
                .expect("Stream doesn't exist")
                .clone();
            let stream_err = stream_out.clone();
            let stream_exit = stream_out.clone();

            if let Some(stdout) = stdout {
                let future = async move {
                    // TODO: use BufReader::new().lines()
                    let mut reader = futures_lite::io::BufReader::new(stdout);
                    loop {
                        let mut buf = String::new();
                        match reader.read_line(&mut buf).await {
                            Ok(0) => break,
                            Ok(_) => {
                                let mut stream = stream_out.lock().expect("Couldn't lock stream");
                                crate::api::send_to_client(
                                    &mut stream,
                                    &OutgoingMsg::CallCallback {
                                        callback_id,
                                        args: Some(Args::Spawn {
                                            stdout: Some(buf.trim_end_matches('\n').to_string()),
                                            stderr: None,
                                            exit_code: None,
                                            exit_msg: None,
                                        }),
                                    },
                                )
                                .expect("Send to client failed"); // TODO: notify instead of crash
                            }
                            Err(err) => {
                                tracing::warn!("child read err: {err}");
                                break;
                            }
                        }
                    }
                };

                // This is not important enough to crash on error, so just print the error instead
                if let Err(err) = self.async_scheduler.schedule(future) {
                    tracing::error!("Failed to schedule future: {err}");
                }
            }
            if let Some(stderr) = stderr {
                let future = async move {
                    let mut reader = futures_lite::io::BufReader::new(stderr);
                    loop {
                        let mut buf = String::new();
                        match reader.read_line(&mut buf).await {
                            Ok(0) => break,
                            Ok(_) => {
                                let mut stream = stream_err.lock().expect("Couldn't lock stream");
                                crate::api::send_to_client(
                                    &mut stream,
                                    &OutgoingMsg::CallCallback {
                                        callback_id,
                                        args: Some(Args::Spawn {
                                            stdout: None,
                                            stderr: Some(buf.trim_end_matches('\n').to_string()),
                                            exit_code: None,
                                            exit_msg: None,
                                        }),
                                    },
                                )
                                .expect("Send to client failed"); // TODO: notify instead of crash
                            }
                            Err(err) => {
                                tracing::warn!("child read err: {err}");
                                break;
                            }
                        }
                    }
                };
                if let Err(err) = self.async_scheduler.schedule(future) {
                    tracing::error!("Failed to schedule future: {err}");
                }
            }

            let future = async move {
                match child.status().await {
                    Ok(exit_status) => {
                        let mut stream = stream_exit.lock().expect("Couldn't lock stream");
                        crate::api::send_to_client(
                            &mut stream,
                            &OutgoingMsg::CallCallback {
                                callback_id,
                                args: Some(Args::Spawn {
                                    stdout: None,
                                    stderr: None,
                                    exit_code: exit_status.code(),
                                    exit_msg: Some(exit_status.to_string()),
                                }),
                            },
                        )
                        .expect("Send to client failed"); // TODO: notify instead of crash
                    }
                    Err(err) => {
                        tracing::warn!("child wait() err: {err}");
                    }
                }
            };
            if let Err(err) = self.async_scheduler.schedule(future) {
                tracing::error!("Failed to schedule future: {err}");
            }
        }
    }

    pub fn re_layout(&mut self, output: &Output) {
        let windows = self
            .windows
            .iter()
            .filter(|win| {
                win.with_state(|state| {
                    state
                        .tags
                        .iter()
                        .any(|tag| tag.output(self).is_some_and(|op| &op == output))
                })
            })
            .cloned()
            .collect::<Vec<_>>();
        let (render, do_not_render) = output.with_state(|state| {
            let first_tag = state.focused_tags().next();
            if let Some(first_tag) = first_tag {
                first_tag.layout().layout(
                    self.windows.clone(),
                    state.focused_tags().cloned().collect(),
                    &self.space,
                    output,
                );
            }

            windows.iter().cloned().partition::<Vec<_>, _>(|win| {
                win.with_state(|win_state| {
                    if win_state.floating.is_floating() {
                        return true;
                    }
                    for tag in win_state.tags.iter() {
                        if state.focused_tags().any(|tg| tg == tag) {
                            return true;
                        }
                    }
                    false
                })
            })
        });

        let clone = render.clone();
        self.loop_handle.insert_idle(|data| {
            schedule_on_commit(data, clone, |dt| {
                for win in do_not_render {
                    dt.state.space.unmap_elem(&win);
                }
            })
        });

        // let blocker = WindowBlockerAll::new(render.clone());
        // blocker.insert_into_loop(self);
        // for win in render.iter() {
        //     compositor::add_blocker(win.toplevel().wl_surface(), blocker.clone());
        // }

        // let (blocker, source) = WindowBlocker::block_all::<B>(render.clone());
        // for win in render.iter() {
        //     compositor::add_blocker(win.toplevel().wl_surface(), blocker.clone());
        // }
        // self.loop_handle.insert_idle(move |data| source(render.clone(), data));

        // let (blocker, source) = WindowBlocker::new::<B>(render.clone());
        // for win in render.iter() {
        //     compositor::add_blocker(win.toplevel().wl_surface(), blocker.clone());
        // }
        // self.loop_handle.insert_idle(move |data| source(render.clone(), render.clone(), data));
    }
}
/// Schedule something to be done when windows have finished committing and have become
/// idle.
pub fn schedule_on_commit<F, B: Backend>(
    data: &mut CalloopData<B>,
    windows: Vec<Window>,
    on_commit: F,
) where
    F: FnOnce(&mut CalloopData<B>) + 'static,
{
    for window in windows.iter() {
        if window.with_state(|state| !matches!(state.resize_state, WindowResizeState::Idle)) {
            data.state.loop_handle.insert_idle(|data| {
                schedule_on_commit(data, windows, on_commit);
            });
            return;
        }
    }

    on_commit(data);
}

impl<B: Backend> State<B> {
    pub fn init(
        backend_data: B,
        display: &mut Display<Self>,
        loop_signal: LoopSignal,
        loop_handle: LoopHandle<'static, CalloopData<B>>,
    ) -> Result<Self, Box<dyn Error>> {
        let socket = ListeningSocketSource::new_auto()?;
        let socket_name = socket.socket_name().to_os_string();

        std::env::set_var("WAYLAND_DISPLAY", socket_name.clone());

        // Opening a new process will use up a few file descriptors, around 10 for Alacritty, for
        // example. Because of this, opening up only around 100 processes would exhaust the file
        // descriptor limit on my system (Arch btw) and cause a "Too many open files" crash.
        //
        // To fix this, I just set the limit to be higher. As Pinnacle is the whole graphical
        // environment, I *think* this is ok.
        if let Err(err) = smithay::reexports::nix::sys::resource::setrlimit(
            smithay::reexports::nix::sys::resource::Resource::RLIMIT_NOFILE,
            65536,
            65536 * 2,
        ) {
            tracing::error!("Could not raise fd limit: errno {err}");
        }

        loop_handle.insert_source(socket, |stream, _metadata, data| {
            data.display
                .handle()
                .insert_client(stream, Arc::new(ClientState::default()))
                .expect("Could not insert client into loop handle");
        })?;

        loop_handle.insert_source(
            Generic::new(
                display.backend().poll_fd().as_raw_fd(),
                Interest::READ,
                Mode::Level,
            ),
            |_readiness, _metadata, data| {
                data.display.dispatch_clients(&mut data.state)?;
                Ok(PostAction::Continue)
            },
        )?;

        let (tx_channel, rx_channel) = calloop::channel::channel::<Msg>();

        // We want to replace the client if a new one pops up
        // TODO: there should only ever be one client working at a time, and creating a new client
        // |     when one is already running should be impossible.
        // INFO: this source try_clone()s the stream
        loop_handle.insert_source(PinnacleSocketSource::new(tx_channel)?, |stream, _, data| {
            if let Some(old_stream) = data
                .state
                .api_state
                .stream
                .replace(Arc::new(Mutex::new(stream)))
            {
                old_stream
                    .lock()
                    .expect("Couldn't lock old stream")
                    .shutdown(std::net::Shutdown::Both)
                    .expect("Couldn't shutdown old stream");
            }
        })?;

        let (executor, sched) =
            calloop::futures::executor::<()>().expect("Couldn't create executor");
        loop_handle.insert_source(executor, |_, _, _| {})?;

        // TODO: move all this into the lua api
        let config_path = std::env::var("PINNACLE_CONFIG").unwrap_or_else(|_| {
            let mut default_path =
                std::env::var("XDG_CONFIG_HOME").unwrap_or("~/.config".to_string());
            default_path.push_str("/pinnacle/init.lua");
            default_path
        });

        if Path::new(&config_path).exists() {
            let lua_path = std::env::var("LUA_PATH").expect("Lua is not installed!");
            let mut local_lua_path = std::env::current_dir()
                .expect("Couldn't get current dir")
                .to_string_lossy()
                .to_string();
            local_lua_path.push_str("/api/lua"); // TODO: get from crate root and do dynamically
            let new_lua_path =
            format!("{local_lua_path}/?.lua;{local_lua_path}/?/init.lua;{local_lua_path}/lib/?.lua;{local_lua_path}/lib/?/init.lua;{lua_path}");

            let lua_cpath = std::env::var("LUA_CPATH").expect("Lua is not installed!");
            let new_lua_cpath = format!("{local_lua_path}/lib/?.so;{lua_cpath}");

            std::process::Command::new("lua5.4")
                .arg(config_path)
                .env("LUA_PATH", new_lua_path)
                .env("LUA_CPATH", new_lua_cpath)
                .spawn()
                .expect("Could not start config process");
        } else {
            tracing::error!("Could not find {}", config_path);
        }

        let display_handle = display.handle();
        let mut seat_state = SeatState::new();
        let mut seat = seat_state.new_wl_seat(&display_handle, backend_data.seat_name());
        seat.add_pointer();
        seat.add_keyboard(XkbConfig::default(), 200, 25)?;

        loop_handle.insert_idle(|data| {
            data.state
                .loop_handle
                .insert_source(rx_channel, |msg, _, data| match msg {
                    Event::Msg(msg) => data.state.handle_msg(msg),
                    Event::Closed => todo!(),
                })
                .unwrap(); // TODO: unwrap
        });

        Ok(Self {
            backend_data,
            loop_signal,
            loop_handle,
            clock: Clock::<Monotonic>::new()?,
            compositor_state: CompositorState::new::<Self>(&display_handle),
            data_device_state: DataDeviceState::new::<Self>(&display_handle),
            seat_state,
            pointer_location: (0.0, 0.0).into(),
            shm_state: ShmState::new::<Self>(&display_handle, vec![]),
            space: Space::<Window>::default(),
            cursor_status: CursorImageStatus::Default,
            output_manager_state: OutputManagerState::new_with_xdg_output::<Self>(&display_handle),
            xdg_shell_state: XdgShellState::new::<Self>(&display_handle),
            viewporter_state: ViewporterState::new::<Self>(&display_handle),
            fractional_scale_manager_state: FractionalScaleManagerState::new::<Self>(
                &display_handle,
            ),
            input_state: InputState::new(),
            api_state: ApiState::new(),
            focus_state: FocusState::new(),

            seat,

            move_mode: false,
            socket_name: socket_name.to_string_lossy().to_string(),

            popup_manager: PopupManager::default(),

            async_scheduler: sched,

            windows: vec![],
            output_callback_ids: vec![],
        })
    }
}

pub struct CalloopData<B: Backend> {
    pub display: Display<State<B>>,
    pub state: State<B>,
}

#[derive(Default)]
pub struct ClientState {
    pub compositor_state: CompositorClientState,
}
impl ClientData for ClientState {
    fn initialized(&self, _client_id: ClientId) {}

    fn disconnected(&self, _client_id: ClientId, _reason: DisconnectReason) {}
}

#[derive(Debug, Copy, Clone)]
pub struct SurfaceDmabufFeedback<'a> {
    pub render_feedback: &'a DmabufFeedback,
    pub scanout_feedback: &'a DmabufFeedback,
}

// TODO: docs
pub fn take_presentation_feedback(
    output: &Output,
    space: &Space<Window>,
    render_element_states: &RenderElementStates,
) -> OutputPresentationFeedback {
    let mut output_presentation_feedback = OutputPresentationFeedback::new(output);

    space.elements().for_each(|window| {
        if space.outputs_for_element(window).contains(output) {
            window.take_presentation_feedback(
                &mut output_presentation_feedback,
                surface_primary_scanout_output,
                |surface, _| {
                    surface_presentation_feedback_flags_from_states(surface, render_element_states)
                },
            );
        }
    });
    // let map = smithay::desktop::layer_map_for_output(output);
    // for layer_surface in map.layers() {
    //     layer_surface.take_presentation_feedback(
    //         &mut output_presentation_feedback,
    //         surface_primary_scanout_output,
    //         |surface, _| {
    //             surface_presentation_feedback_flags_from_states(surface, render_element_states)
    //         },
    //     );
    // }

    output_presentation_feedback
}

/// State containing the config API's stream.
#[derive(Default)]
pub struct ApiState {
    // TODO: this may not need to be in an arc mutex because of the move to async
    pub stream: Option<Arc<Mutex<UnixStream>>>,
}

impl ApiState {
    pub fn new() -> Self {
        Default::default()
    }
}

pub trait WithState {
    type State: Default;
    fn with_state<F, T>(&self, func: F) -> T
    where
        F: FnMut(&mut Self::State) -> T;
}

#[derive(Default, Debug)]
pub struct WlSurfaceState {
    pub resize_state: ResizeSurfaceState,
}

impl WithState for WlSurface {
    type State = WlSurfaceState;

    fn with_state<F, T>(&self, mut func: F) -> T
    where
        F: FnMut(&mut Self::State) -> T,
    {
        compositor::with_states(self, |states| {
            states
                .data_map
                .insert_if_missing(RefCell::<Self::State>::default);
            let state = states
                .data_map
                .get::<RefCell<Self::State>>()
                .expect("This should never happen");

            func(&mut state.borrow_mut())
        })
    }
}