// client/src/output/video.rs

use gstreamer as gst;
use gstreamer_app as gst_app;
use gst::prelude::*;
use gst_app::prelude::*;
use lesavka_common::lesavka::VideoPacket;
use winit::window::{Window, WindowAttributes};
use winit::event_loop::EventLoop;

pub struct MonitorWindow {
    id: u32,
    _window: Window,
    src: gst_app::AppSrc,
}

impl MonitorWindow {
    pub fn new(id: u32, el: &EventLoop<()>) -> anyhow::Result<Self> {
        gst::init()?;

        let window = el.create_window(
            WindowAttributes::default()
                .with_title(format!("Lesavka‑monitor‑{id}"))
                .with_decorations(false)
        )?;

        // appsrc -> decode -> convert -> autovideosink
        let desc = if std::env::var_os("XDG_RUNTIME_DIR").is_some() {
            // graphical
            "appsrc name=src is-live=true format=time do-timestamp=true ! \
             queue ! h264parse ! decodebin ! videoconvert ! autovideosink sync=false"
        } else {
            // headless / debugging over ssh
            "appsrc name=src is-live=true format=time do-timestamp=true ! \
             fakesink sync=false"
        };

        let pipeline = gst::parse::launch(desc)?
            .downcast::<gst::Pipeline>()
            .unwrap();
        
        let src = pipeline
            .by_name("src").unwrap()
            .downcast::<gst_app::AppSrc>().unwrap();

        src.set_latency(gst::ClockTime::NONE, gst::ClockTime::NONE);
        pipeline.set_state(gst::State::Playing)?;

        Ok(Self { id, _window: window, src })
    }

    pub fn push_packet(&self, pkt: VideoPacket) {
        let mut buf = gst::Buffer::from_slice(pkt.data);
        buf.get_mut().unwrap()
            .set_pts(Some(gst::ClockTime::from_useconds(pkt.pts)));
        let _ = self.src.push_buffer(buf);
    }
}