feat(auto-reply): add model fallback lifecycle visibility in status, verbose logs, and WebUI (#20704)

src/auto-reply/model-runtime.ts

@@ -0,0 +1,93 @@
+import type { SessionEntry } from "../config/sessions.js";
+
+export function formatProviderModelRef(providerRaw: string, modelRaw: string): string {
+  const provider = String(providerRaw ?? "").trim();
+  const model = String(modelRaw ?? "").trim();
+  if (!provider) {
+    return model;
+  }
+  if (!model) {
+    return provider;
+  }
+  const prefix = `${provider}/`;
+  if (model.toLowerCase().startsWith(prefix.toLowerCase())) {
+    const normalizedModel = model.slice(prefix.length).trim();
+    if (normalizedModel) {
+      return `${provider}/${normalizedModel}`;
+    }
+  }
+  return `${provider}/${model}`;
+}
+
+type ModelRef = {
+  provider: string;
+  model: string;
+  label: string;
+};
+
+function normalizeModelWithinProvider(provider: string, modelRaw: string): string {
+  const model = String(modelRaw ?? "").trim();
+  if (!provider || !model) {
+    return model;
+  }
+  const prefix = `${provider}/`;
+  if (model.toLowerCase().startsWith(prefix.toLowerCase())) {
+    const withoutPrefix = model.slice(prefix.length).trim();
+    if (withoutPrefix) {
+      return withoutPrefix;
+    }
+  }
+  return model;
+}
+
+function normalizeModelRef(
+  rawModel: string,
+  fallbackProvider: string,
+  parseEmbeddedProvider = false,
+): ModelRef {
+  const trimmed = String(rawModel ?? "").trim();
+  const slashIndex = parseEmbeddedProvider ? trimmed.indexOf("/") : -1;
+  if (slashIndex > 0) {
+    const provider = trimmed.slice(0, slashIndex).trim();
+    const model = trimmed.slice(slashIndex + 1).trim();
+    if (provider && model) {
+      return {
+        provider,
+        model,
+        label: `${provider}/${model}`,
+      };
+    }
+  }
+  const provider = String(fallbackProvider ?? "").trim();
+  const dedupedModel = normalizeModelWithinProvider(provider, trimmed);
+  return {
+    provider,
+    model: dedupedModel || trimmed,
+    label: provider ? formatProviderModelRef(provider, dedupedModel || trimmed) : trimmed,
+  };
+}
+
+export function resolveSelectedAndActiveModel(params: {
+  selectedProvider: string;
+  selectedModel: string;
+  sessionEntry?: Pick<SessionEntry, "modelProvider" | "model">;
+}): {
+  selected: ModelRef;
+  active: ModelRef;
+  activeDiffers: boolean;
+} {
+  const selected = normalizeModelRef(params.selectedModel, params.selectedProvider);
+  const runtimeModel = params.sessionEntry?.model?.trim();
+  const runtimeProvider = params.sessionEntry?.modelProvider?.trim();
+
+  const active = runtimeModel
+    ? normalizeModelRef(runtimeModel, runtimeProvider || selected.provider, !runtimeProvider)
+    : selected;
+  const activeDiffers = active.provider !== selected.provider || active.model !== selected.model;
+
+  return {
+    selected,
+    active,
+    activeDiffers,
+  };
+}