Limit voice selection to avoid awkward assignments

src/kokoro.rs

@@ -3,6 +3,40 @@ use reqwest::Url;
 use serde::{Deserialize, Serialize};
 use std::time::Duration;
 
+/// Curated English Kokoro voices used for NPC selection and the voice manager.
+///
+/// Keeping this allowlist here means a server update cannot unexpectedly add
+/// voices to Mudmouth's random assignment pool.
+const NPC_VOICE_ALLOWLIST: &[&str] = &[
+    "af_heart",
+    "af_bella",
+    "af_nicole",
+    "af_alloy",
+    "af_aoede",
+    "af_kore",
+    "af_nova",
+    "af_sarah",
+    "af_river",
+    "af_jessica",
+    "af_sky",
+    "am_michael",
+    "am_fenrir",
+    "am_eric",
+    "am_echo",
+    "am_liam",
+    "am_onyx",
+    "am_adam",
+    "am_puck",
+    "bf_alice",
+    "bf_emma",
+    "bf_isabella",
+    "bf_lily",
+    "bm_daniel",
+    "bm_fable",
+    "bm_george",
+    "bm_lewis",
+];
+
 #[derive(Clone)]
 pub struct KokoroClient {
     client: reqwest::Client,
@@ -80,6 +114,7 @@ impl KokoroClient {
             .into_voices()
             .into_iter()
             .map(|voice| voice.id)
+            .filter(|voice| NPC_VOICE_ALLOWLIST.contains(&voice.as_str()))
             .collect())
     }
 
@@ -136,7 +171,7 @@ mod tests {
         let url = serve_once(
             "200 OK",
             "application/json",
-            br#"[{"id":"af_heart","name":"Heart"},{"id":"am_adam","name":"Adam"}]"#,
+            br#"[{"id":"af_heart","name":"Heart"},{"id":"am_adam","name":"Adam"},{"id":"af_onyx","name":"Onyx"}]"#,
         );
         let voices = KokoroClient::new(&url).unwrap().voices().await.unwrap();
         assert_eq!(voices, vec!["af_heart", "am_adam"]);