Add workspace screen sharing (#64)

Add workspace selection to the screen-sharing picker with pinned capture, privacy filtering and bounded capture resources. Refresh captured tab labels when title or app-ID metadata changes.

portal/src/workspace.rs

@@ -0,0 +1,177 @@
+//! Portal compatibility: a workspace is an explicitly chosen, restricted view
+//! of an existing monitor. Offer it only when MONITOR was requested; never
+//! advertise an invented WORKSPACE bit or VIRTUAL (which creates a new monitor).
+use crate::backend::Options;
+use crate::capture::Source;
+use crate::stream::Ready;
+use serde_json::Value as Json;
+use zbus::zvariant::Value;
+
+pub(crate) fn sources(workspaces: &Json, outputs: &Json) -> Result<Vec<Source>, String> {
+    let workspaces = workspaces.as_array().ok_or("Invalid workspace list")?;
+    let outputs = outputs.as_array().ok_or("Invalid output list")?;
+    Ok(workspaces
+        .iter()
+        .take(128)
+        .filter_map(|workspace| {
+            let id = workspace["id"].as_u64()?;
+            let owner = workspace["output"].as_u64()?;
+            let output = outputs
+                .iter()
+                .find(|output| output["id"].as_u64() == Some(owner) && output["enabled"] == true)?;
+            let integer = |key: &str| {
+                output[key]
+                    .as_i64()
+                    .and_then(|value| i32::try_from(value).ok())
+            };
+            let (width, height) = (integer("width")?, integer("height")?);
+            if width <= 0 || height <= 0 {
+                return None;
+            }
+            Some(Source {
+                name: format!("workspace:{id}"),
+                label: format!(
+                    "Workspace {} · {}",
+                    workspace["index"].as_u64()?,
+                    output["name"].as_str()?
+                ),
+                width,
+                height,
+                x: integer("x")?,
+                y: integer("y")?,
+                scale: 1,
+            })
+        })
+        .collect())
+}
+
+pub(crate) fn selection_unchanged(
+    selected: &[Source],
+    before: &Json,
+    old_outputs: &Json,
+    after: &Json,
+    new_outputs: &Json,
+) -> bool {
+    selected.iter().filter_map(Source::workspace_id).all(|id| {
+        let owner = |workspaces: &Json| {
+            workspaces
+                .as_array()?
+                .iter()
+                .find(|workspace| workspace["id"].as_u64() == Some(id))?["output"]
+                .as_u64()
+        };
+        let Some(old_owner) = owner(before) else {
+            return false;
+        };
+        if owner(after) != Some(old_owner) {
+            return false;
+        }
+        let output = |outputs: &Json| {
+            outputs
+                .as_array()?
+                .iter()
+                .find(|output| output["id"].as_u64() == Some(old_owner))
+                .cloned()
+        };
+        let (Some(old), Some(new)) = (output(old_outputs), output(new_outputs)) else {
+            return false;
+        };
+        new["enabled"] == true
+            && [
+                "identity",
+                "name",
+                "width",
+                "height",
+                "x",
+                "y",
+                "scale",
+                "transform",
+                "current_mode",
+            ]
+            .into_iter()
+            .all(|key| old[key] == new[key])
+    })
+}
+
+pub(crate) fn metadata(source: &Source, ready: &Ready) -> Result<Options, String> {
+    if source.workspace_id().is_none()
+        || ready.width == 0
+        || ready.height == 0
+        || ready.logical_size != Some((source.width as u32, source.height as u32))
+    {
+        return Err("Invalid workspace stream geometry".into());
+    }
+    Ok(Options::from([
+        ("source_type".into(), 1u32.into()),
+        (
+            "size".into(),
+            Value::from((source.width, source.height))
+                .try_to_owned()
+                .map_err(|error| error.to_string())?,
+        ),
+    ]))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::capture::SourceKind;
+    use serde_json::json;
+
+    fn outputs() -> Json {
+        json!([{"id": 5, "name": "DP-1", "enabled": true, "width": 1920, "height": 1080,
+            "x": 0, "y": 0, "scale": 2.0, "identity": "drm-edid:test", "transform": "normal",
+            "current_mode": {"width": 3840, "height": 2160}}])
+    }
+
+    #[test]
+    fn workspace_selection_uses_identity_not_index_and_never_remembers_consent() {
+        let outputs = outputs();
+        let before = json!([{"id": 42, "output": 5, "index": 1}]);
+        let selected = sources(&before, &outputs).unwrap();
+        assert_eq!(selected.len(), 1);
+        assert_eq!(selected[0].kind(), SourceKind::Workspace(42));
+        assert_eq!(selected[0].label, "Workspace 1 · DP-1");
+        let renamed = json!([{"id": 42, "output": 5, "index": 3}]);
+        assert!(selection_unchanged(
+            &selected, &before, &outputs, &renamed, &outputs
+        ));
+        let replaced = json!([{"id": 43, "output": 5, "index": 1}]);
+        assert!(!selection_unchanged(
+            &selected, &before, &outputs, &replaced, &outputs
+        ));
+        let moved = json!([{"id": 42, "output": 6, "index": 1}]);
+        assert!(!selection_unchanged(
+            &selected, &before, &outputs, &moved, &outputs
+        ));
+        let mut resized = outputs.clone();
+        resized[0]["current_mode"]["width"] = 2560.into();
+        assert!(!selection_unchanged(
+            &selected, &before, &outputs, &before, &resized
+        ));
+        assert!(
+            crate::restore::Restore::create("org.test.App", false, &selected, &outputs, 2)
+                .is_none()
+        );
+    }
+
+    #[test]
+    fn workspace_metadata_keeps_logical_geometry_for_a_smaller_pixel_canvas() {
+        let selected = sources(&json!([{"id": 42, "output": 5, "index": 1}]), &outputs()).unwrap();
+        let mut ready = Ready {
+            node: 7,
+            width: 1280,
+            height: 720,
+            logical_size: Some((1920, 1080)),
+        };
+        let metadata = metadata(&selected[0], &ready).unwrap();
+        assert_eq!(u32::try_from(&metadata["source_type"]).unwrap(), 1);
+        assert!(!metadata.contains_key("position"));
+        ready.logical_size = None;
+        assert!(super::metadata(&selected[0], &ready).is_err());
+        for name in ["window:", "workspace:no", "workspace:18446744073709551616"] {
+            assert_eq!(SourceKind::parse(name), SourceKind::Invalid);
+        }
+        assert_eq!(SourceKind::parse("DP-1"), SourceKind::Monitor);
+    }
+}