A card of one's own: one_per_person, prefilled, replaced on send; no double sends; refusals are shown

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GT37Z1Xtfd9pUuQtMTg6Yt

src/answers.rs

@@ -114,6 +114,73 @@ pub async fn store_answer(
     Ok(())
 }
 
+/// Whose a record is, on an alternative that keeps one per person
+/// (`one_per_person`): the signed-in person's username, written by the
+/// server into the record's fields, never taken from the form.
+pub const OWNER_FIELD: &str = "by";
+
+/// Every record in `bucket` that belongs to `username`, newest first.
+#[cfg(feature = "ssr")]
+pub async fn own_records(js: &async_nats::jetstream::Context, bucket: &str, username: &str) -> Vec<Answer> {
+    use futures::TryStreamExt;
+    let Ok(store) = js.get_key_value(bucket).await else { return Vec::new() };
+    let keys: Vec<String> = match store.keys().await {
+        Ok(keys) => keys.try_collect().await.unwrap_or_default(),
+        Err(_) => return Vec::new(),
+    };
+    let mut own = Vec::new();
+    for key in keys {
+        let Ok(Some(bytes)) = store.get(&key).await else { continue };
+        let Ok(answer) = serde_json::from_slice::<Answer>(&bytes) else { continue };
+        if answer.responses.get(OWNER_FIELD).and_then(|v| v.as_str()) == Some(username) {
+            own.push(answer);
+        }
+    }
+    own.sort_by(|a, b| (b.submitted_ms, &b.id).cmp(&(a.submitted_ms, &a.id)));
+    own
+}
+
+/// A person keeps one card: of their records still in the bucket's
+/// first state, only the newest stays in the list, and the rest leave
+/// it (the event log keeps them). Run after every store, so two sends
+/// racing each other - a double click - both settle on the same one.
+#[cfg(feature = "ssr")]
+pub async fn keep_newest_own(js: &async_nats::jetstream::Context, bucket: &str, initial: &str, username: &str) {
+    let own = own_records(js, bucket, username).await;
+    let Ok(store) = js.get_key_value(bucket).await else { return };
+    for older in own.iter().filter(|a| a.state == initial).skip(1) {
+        if let Err(e) = store.delete(&older.id).await {
+            tracing::error!(bucket, id = %older.id, error = %e, "could not retire an older own record");
+        }
+    }
+}
+
+/// Fills the form of every `one_per_person` alternative with what the
+/// signed-in person's own newest record says, so sending it again is
+/// editing their card. A file field shows the file already there, at
+/// the address a list would open it from, and may be left empty to
+/// keep it.
+#[cfg(feature = "ssr")]
+pub async fn fill_own(js: &async_nats::jetstream::Context, question: &mut crate::content::Question, user: Option<&crate::auth::User>) {
+    let Some(user) = user else { return };
+    for alt in &mut question.alternatives {
+        let (true, Some(bucket)) = (alt.one_per_person, alt.record_as.clone()) else { continue };
+        let Some(mine) = own_records(js, &bucket, &user.username).await.into_iter().next() else { continue };
+        for req in alt.features.iter_mut().flat_map(|f| f.requirements.iter_mut()) {
+            if req.kind == "hidden" {
+                continue;
+            }
+            let Some(value) = mine.responses.get(&req.name).and_then(|v| v.as_str()).filter(|v| !v.trim().is_empty()) else { continue };
+            if req.kind == "file" {
+                req.value = Some(format!("/attachment/{bucket}/{}/{}", mine.id, req.name));
+                req.optional = true;
+            } else {
+                req.value = Some(value.to_string());
+            }
+        }
+    }
+}
+
 /// One selected row's pending transition. `feature_name` is per-item
 /// so a batch can span more than one resource feature on the same
 /// alternative.