1 files changed, 42 insertions, 1 deletions

diff --git a/crates/dinggerd/src/hooks.rs b/crates/dinggerd/src/hooks.rs
index 1718ff8..82fa7bd 100644
--- a/crates/dinggerd/src/hooks.rs
+++ b/crates/dinggerd/src/hooks.rs
@@ -28,7 +28,9 @@
 //! on an old extension once it is idle and off screen.
 //!
 //! It also carries the `draft` in the agent's input box ("" for none), for
-//! marking a draft you left behind; never logged.
+//! marking a draft you left behind; never logged. And `context`: how full
+//! the agent's context window is, in percent, as pi's footer shows it (""
+//! when unknown, as right after compacting).
 //!
 //! Each line is answered with `{"ok":true}`.
 //!
@@ -74,6 +76,8 @@ struct PaneReports {
     control: Option<String>,
     /// The draft in the agent's input box, as one line ("" for none).
     draft: Option<String>,
+    /// How full its context window is: whole percent ("" when unknown).
+    context: Option<String>,
     /// When the last report arrived.
     at: Option<Instant>,
 }
@@ -172,6 +176,8 @@ struct HookParams {
     control: Option<String>,
     #[serde(default)]
     draft: Option<String>,
+    #[serde(default)]
+    context: Option<String>,
 }
 
 fn handle_stream(stream: UnixStream) {
@@ -239,6 +245,7 @@ fn handle_stream(stream: UnixStream) {
             extension: params.extension,
             control: params.control,
             draft: params.draft,
+            context: params.context,
         };
         record(params.pane_id, state, reported);
         wake();
@@ -253,6 +260,7 @@ struct Reported {
     extension: Option<String>,
     control: Option<String>,
     draft: Option<String>,
+    context: Option<String>,
 }
 
 /// The longest draft kept: enough to find an agent by it.
@@ -298,6 +306,24 @@ fn record(pane_id: String, state: Option<AgentState>, reported: Reported) {
     if let Some(draft) = reported.draft {
         pane.draft = Some(draft_line(&draft));
     }
+    if let Some(context) = reported.context {
+        pane.context = Some(context_percent(&context));
+    }
+}
+
+/// A reported context use as whole percent ("12.6" is "13"); "" for
+/// unknown, or anything not a percentage.
+fn context_percent(value: &str) -> String {
+    match value.trim().parse::<f64>() {
+        Ok(percent) if percent.is_finite() && percent >= 0.0 => format!("{:.0}", percent.min(999.0)),
+        _ => String::new(),
+    }
+}
+
+/// How full the pane's agent's context window is ("" when unknown), if its
+/// extension reports it.
+pub fn context(pane_id: &str) -> Option<String> {
+    reports().get(pane_id).and_then(|pane| pane.context.clone())
 }
 
 /// Start listening; reports accumulate for the watcher to consume.
@@ -441,6 +467,21 @@ mod tests {
     }
 
     #[test]
+    fn context_use_is_kept_as_whole_percent_until_reported_again() {
+        let context = |text: &str| Reported { context: Some(text.into()), ..Default::default() };
+        assert_eq!(super::context("%t6"), None, "an extension that does not report it");
+        record("%t6".into(), None, context("12.6"));
+        assert_eq!(super::context("%t6").as_deref(), Some("13"));
+        record("%t6".into(), None, Reported::default());
+        assert_eq!(super::context("%t6").as_deref(), Some("13"), "kept by a report without one");
+        record("%t6".into(), None, context(""));
+        assert_eq!(super::context("%t6").as_deref(), Some(""), "unknown, after compacting");
+        for (value, want) in [("0", "0"), ("0.4", "0"), ("97.5", "98"), ("1e9", "999"), ("-3", ""), ("NaN", ""), ("x", "")] {
+            assert_eq!(context_percent(value), want, "{value}");
+        }
+    }
+
+    #[test]
     fn a_draft_is_kept_as_one_short_line_until_reported_again() {
         let draft = |text: &str| Reported { draft: Some(text.into()), ..Default::default() };
         record("%t5".into(), Some(AgentState::Idle), Reported::default());