Implement IPC for the overview state (#1526)

* Implement IPC for the overview state

* Update Overview IPC to maintain naming consistency, renamed OverviewToggled to be more clear, simplify overview state request on the server, consolidate ipc refresh

* Fix Overview is_open in IPC client

* Change opened to is_open

* Update niri-ipc/src/lib.rs

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

* Update niri-ipc/src/state.rs

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

* Update src/ipc/client.rs

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

* Update src/ipc/client.rs

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

* Add overview state to EventStreamStatePart replicate and apply

* Fix formatting

* Rename Overview to OverviewState

---------

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

5 files changed, 101 insertions, 3 deletions

diff --git a/niri-ipc/src/lib.rs b/niri-ipc/src/lib.rs
index 325cdef0..75d9a543 100644
--- a/niri-ipc/src/lib.rs
+++ b/niri-ipc/src/lib.rs
@@ -97,6 +97,8 @@ pub enum Request {
     EventStream,
     /// Respond with an error (for testing error handling).
     ReturnError,
+    /// Request information about the overview.
+    OverviewState,
 }
 
 /// Reply from niri to client.
@@ -139,6 +141,16 @@ pub enum Response {
     PickedColor(Option<PickedColor>),
     /// Output configuration change result.
     OutputConfigChanged(OutputConfigChanged),
+    /// Information about the overview.
+    OverviewState(Overview),
+}
+
+/// Overview information.
+#[derive(Serialize, Deserialize, Debug, Clone)]
+#[cfg_attr(feature = "json-schema", derive(schemars::JsonSchema))]
+pub struct Overview {
+    /// Whether the overview is currently open.
+    pub is_open: bool,
 }
 
 /// Color picked from the screen.
@@ -1269,6 +1281,11 @@ pub enum Event {
         /// Index of the newly active layout.
         idx: u8,
     },
+    /// The overview was opened or closed.
+    OverviewOpenedOrClosed {
+        /// The new state of the overview.
+        is_open: bool,
+    },
 }
 
 impl FromStr for WorkspaceReferenceArg {
diff --git a/niri-ipc/src/state.rs b/niri-ipc/src/state.rs
index 2ab58fc3..0689104d 100644
--- a/niri-ipc/src/state.rs
+++ b/niri-ipc/src/state.rs
@@ -40,6 +40,9 @@ pub struct EventStreamState {
 
     /// State of the keyboard layouts.
     pub keyboard_layouts: KeyboardLayoutsState,
+
+    /// State of the overview.
+    pub overview: OverviewState,
 }
 
 /// The workspaces state communicated over the event stream.
@@ -63,12 +66,20 @@ pub struct KeyboardLayoutsState {
     pub keyboard_layouts: Option<KeyboardLayouts>,
 }
 
+/// The overview state communicated over the event stream.
+#[derive(Debug, Default)]
+pub struct OverviewState {
+    /// Whether the overview is currently open.
+    pub is_open: bool,
+}
+
 impl EventStreamStatePart for EventStreamState {
     fn replicate(&self) -> Vec<Event> {
         let mut events = Vec::new();
         events.extend(self.workspaces.replicate());
         events.extend(self.windows.replicate());
         events.extend(self.keyboard_layouts.replicate());
+        events.extend(self.overview.replicate());
         events
     }
 
@@ -76,6 +87,7 @@ impl EventStreamStatePart for EventStreamState {
         let event = self.workspaces.apply(event)?;
         let event = self.windows.apply(event)?;
         let event = self.keyboard_layouts.apply(event)?;
+        let event = self.overview.apply(event)?;
         Some(event)
     }
 }
@@ -192,3 +204,21 @@ impl EventStreamStatePart for KeyboardLayoutsState {
         None
     }
 }
+
+impl EventStreamStatePart for OverviewState {
+    fn replicate(&self) -> Vec<Event> {
+        vec![Event::OverviewOpenedOrClosed {
+            is_open: self.is_open,
+        }]
+    }
+
+    fn apply(&mut self, event: Event) -> Option<Event> {
+        match event {
+            Event::OverviewOpenedOrClosed { is_open } => {
+                self.is_open = is_open;
+            }
+            event => return Some(event),
+        }
+        None
+    }
+}
diff --git a/src/cli.rs b/src/cli.rs
index ea8c422d..cb3cc0ab 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -105,4 +105,6 @@ pub enum Msg {
     Version,
     /// Request an error from the running niri instance.
     RequestError,
+    /// Print the overview state.
+    OverviewState,
 }
diff --git a/src/ipc/client.rs b/src/ipc/client.rs
index d4165733..6f969703 100644
--- a/src/ipc/client.rs
+++ b/src/ipc/client.rs
@@ -5,8 +5,8 @@ use anyhow::{anyhow, bail, Context};
 use niri_config::OutputName;
 use niri_ipc::socket::Socket;
 use niri_ipc::{
-    Event, KeyboardLayouts, LogicalOutput, Mode, Output, OutputConfigChanged, Request, Response,
-    Transform, Window,
+    Event, KeyboardLayouts, LogicalOutput, Mode, Output, OutputConfigChanged, Overview, Request,
+    Response, Transform, Window,
 };
 use serde_json::json;
 
@@ -32,6 +32,7 @@ pub fn handle_msg(msg: Msg, json: bool) -> anyhow::Result<()> {
         Msg::KeyboardLayouts => Request::KeyboardLayouts,
         Msg::EventStream => Request::EventStream,
         Msg::RequestError => Request::ReturnError,
+        Msg::OverviewState => Request::OverviewState,
     };
 
     let socket = Socket::connect().context("error connecting to the niri socket")?;
@@ -435,9 +436,31 @@ pub fn handle_msg(msg: Msg, json: bool) -> anyhow::Result<()> {
                     Event::KeyboardLayoutSwitched { idx } => {
                         println!("Keyboard layout switched: {idx}");
                     }
+                    Event::OverviewOpenedOrClosed { is_open: opened } => {
+                        println!("Overview toggled: {opened}");
+                    }
                 }
             }
         }
+        Msg::OverviewState => {
+            let Response::OverviewState(response) = response else {
+                bail!("unexpected response: expected Overview, got {response:?}");
+            };
+
+            if json {
+                let response =
+                    serde_json::to_string(&response).context("error formatting response")?;
+                println!("{response}");
+                return Ok(());
+            }
+
+            let Overview { is_open } = response;
+            if is_open {
+                println!("Overview is open.");
+            } else {
+                println!("Overview is closed.");
+            }
+        }
     }
 
     Ok(())
diff --git a/src/ipc/server.rs b/src/ipc/server.rs
index 2c948cac..06ff0fd1 100644
--- a/src/ipc/server.rs
+++ b/src/ipc/server.rs
@@ -16,7 +16,9 @@ use futures_util::io::{AsyncReadExt, BufReader};
 use futures_util::{select_biased, AsyncBufReadExt, AsyncWrite, AsyncWriteExt, FutureExt as _};
 use niri_config::OutputName;
 use niri_ipc::state::{EventStreamState, EventStreamStatePart as _};
-use niri_ipc::{Event, KeyboardLayouts, OutputConfigChanged, Reply, Request, Response, Workspace};
+use niri_ipc::{
+    Event, KeyboardLayouts, OutputConfigChanged, Overview, Reply, Request, Response, Workspace,
+};
 use smithay::desktop::layer_map_for_output;
 use smithay::input::pointer::{
     CursorIcon, CursorImageStatus, Focus, GrabStartData as PointerGrabStartData,
@@ -428,6 +430,11 @@ async fn process(ctx: &ClientCtx, request: Request) -> Reply {
             Response::FocusedOutput(output)
         }
         Request::EventStream => Response::Handled,
+        Request::OverviewState => {
+            let state = ctx.event_stream_state.borrow();
+            let is_open = state.overview.is_open;
+            Response::OverviewState(Overview { is_open })
+        }
     };
 
     Ok(response)
@@ -524,6 +531,7 @@ impl State {
     pub fn ipc_refresh_layout(&mut self) {
         self.ipc_refresh_workspaces();
         self.ipc_refresh_windows();
+        self.ipc_refresh_overview();
     }
 
     fn ipc_refresh_workspaces(&mut self) {
@@ -690,4 +698,22 @@ impl State {
             server.send_event(event);
         }
     }
+
+    pub fn ipc_refresh_overview(&mut self) {
+        let Some(server) = &self.niri.ipc_server else {
+            return;
+        };
+
+        let mut state = server.event_stream_state.borrow_mut();
+        let state = &mut state.overview;
+        let is_open = self.niri.layout.is_overview_open();
+
+        if state.is_open == is_open {
+            return;
+        }
+
+        let event = Event::OverviewOpenedOrClosed { is_open };
+        state.apply(event.clone());
+        server.send_event(event);
+    }
 }