ashpd_pipewire_screen_share.rs

use std::os::fd::{IntoRawFd, OwnedFd};

use ashpd::desktop::{
    screencast::{CursorMode, Screencast, SourceType, Stream as AshStream},
    PersistMode,
};
use pipewire as pw;
use pw::{properties::properties, spa};

use spa::pod::Pod;

struct UserData {
    format: spa::param::video::VideoInfoRaw,
}

async fn open_portal() -> ashpd::Result<(AshStream, OwnedFd)> {
    let proxy = Screencast::new().await?;
    let session = proxy.create_session().await?;
    proxy
        .select_sources(
            &session,
            CursorMode::Embedded,
            SourceType::Monitor.into(),
            false,
            None,
            PersistMode::DoNot,
        )
        .await?;

    let response = proxy.start(&session, None).await?.response()?;
    let stream = response.streams().first().unwrap().to_owned();

    let fd = proxy.open_pipe_wire_remote(&session).await?;

    Ok((stream, fd))
}

async fn start_streaming(node_id: u32, _fd: OwnedFd) -> Result<(), pw::Error> {
    pw::init();

    let mainloop = pw::main_loop::MainLoop::new(None)?;
    let context = pw::context::Context::new(&mainloop)?;
    let core = context.connect(None)?;

    let data = UserData {
        format: Default::default(),
    };

    let stream = pw::stream::Stream::new(
        &core,
        "video-test",
        properties! {
            *pw::keys::MEDIA_TYPE => "Video",
            *pw::keys::MEDIA_CATEGORY => "Capture",
            *pw::keys::MEDIA_ROLE => "Screen",
        },
    )?;

    /*let stream = pw::stream::Stream::<UserData>::with_user_data(
        &mainloop,
        "video-test",
        ,
        data,
    )*/

    let _listener = stream
        .add_local_listener_with_user_data(data)
        .state_changed(|_, _, old, new| {
            println!("State changed: {:?} -> {:?}", old, new);
        })
        .param_changed(|_, user_data, id, param| {
            let Some(param) = param else {
                return;
            };
            if id != pw::spa::param::ParamType::Format.as_raw() {
                return;
            }

            let (media_type, media_subtype) =
                match pw::spa::param::format_utils::parse_format(param) {
                    Ok(v) => v,
                    Err(_) => return,
                };

            if media_type != pw::spa::param::format::MediaType::Video
                || media_subtype != pw::spa::param::format::MediaSubtype::Raw
            {
                return;
            }

            user_data
                .format
                .parse(param)
                .expect("Failed to parse param changed to VideoInfoRaw");

            println!("got video format:");
            println!(
                "  format: {} ({:?})",
                user_data.format.format().as_raw(),
                user_data.format.format()
            );
            println!(
                "  size: {}x{}",
                user_data.format.size().width,
                user_data.format.size().height
            );
            println!(
                "  framerate: {}/{}",
                user_data.format.framerate().num,
                user_data.format.framerate().denom
            );

            // prepare to render video of this size
        })
        .process(|stream, _| {
            match stream.dequeue_buffer() {
                None => println!("out of buffers"),
                Some(mut buffer) => {
                    let datas = buffer.datas_mut();
                    if datas.is_empty() {
                        return;
                    }

                    // copy frame data to screen
                    let data = &mut datas[0];
                    println!("got a frame of size {}", data.chunk().size());
                }
            }
        })
        .register()?;

    println!("Created stream {:#?}", stream);

    let obj = pw::spa::pod::object!(
        pw::spa::utils::SpaTypes::ObjectParamFormat,
        pw::spa::param::ParamType::EnumFormat,
        pw::spa::pod::property!(
            pw::spa::param::format::FormatProperties::MediaType,
            Id,
            pw::spa::param::format::MediaType::Video
        ),
        pw::spa::pod::property!(
            pw::spa::param::format::FormatProperties::MediaSubtype,
            Id,
            pw::spa::param::format::MediaSubtype::Raw
        ),
        pw::spa::pod::property!(
            pw::spa::param::format::FormatProperties::VideoFormat,
            Choice,
            Enum,
            Id,
            pw::spa::param::video::VideoFormat::RGB,
            pw::spa::param::video::VideoFormat::RGB,
            pw::spa::param::video::VideoFormat::RGBA,
            pw::spa::param::video::VideoFormat::RGBx,
            pw::spa::param::video::VideoFormat::BGRx,
            pw::spa::param::video::VideoFormat::YUY2,
            pw::spa::param::video::VideoFormat::I420,
        ),
        pw::spa::pod::property!(
            pw::spa::param::format::FormatProperties::VideoSize,
            Choice,
            Range,
            Rectangle,
            pw::spa::utils::Rectangle {
                width: 320,
                height: 240
            },
            pw::spa::utils::Rectangle {
                width: 1,
                height: 1
            },
            pw::spa::utils::Rectangle {
                width: 4096,
                height: 4096
            }
        ),
        pw::spa::pod::property!(
            pw::spa::param::format::FormatProperties::VideoFramerate,
            Choice,
            Range,
            Fraction,
            pw::spa::utils::Fraction { num: 25, denom: 1 },
            pw::spa::utils::Fraction { num: 0, denom: 1 },
            pw::spa::utils::Fraction {
                num: 1000,
                denom: 1
            }
        ),
    );
    let values: Vec<u8> = pw::spa::pod::serialize::PodSerializer::serialize(
        std::io::Cursor::new(Vec::new()),
        &pw::spa::pod::Value::Object(obj),
    )
    .unwrap()
    .0
    .into_inner();

    let mut params = [Pod::from_bytes(&values).unwrap()];

    stream.connect(
        spa::utils::Direction::Input,
        Some(node_id),
        pw::stream::StreamFlags::AUTOCONNECT | pw::stream::StreamFlags::MAP_BUFFERS,
        &mut params,
    )?;

    println!("Connected stream");

    mainloop.run();

    Ok(())
}

smol_macros::main! {
    async fn main() {
        let (stream, fd) = open_portal().await.expect("failed to open portal");
        println!("node id {}, fd {}", stream.pipe_wire_node_id(), fd.try_clone().unwrap().into_raw_fd());

        if let Err(e) = start_streaming(stream.pipe_wire_node_id(), fd).await {
            eprintln!("Error: {}", e);
        };
    }
}