feat: integrate Pi backend and Pi Web

pi-web/lib/model-discovery-auth.ts

@@ -0,0 +1,58 @@
+import { mkdtempSync, rmSync, writeFileSync } from "fs";
+import { tmpdir } from "os";
+import { join } from "path";
+import { ModelRuntime } from "@earendil-works/pi-coding-agent";
+
+export interface ModelDiscoveryAuth {
+  apiKey?: string;
+  headers: Record<string, string>;
+}
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
+function stringRecord(value: unknown): Record<string, string> {
+  if (!isRecord(value)) return {};
+  return Object.fromEntries(Object.entries(value).filter((entry): entry is [string, string] => typeof entry[1] === "string"));
+}
+
+export async function resolveModelDiscoveryAuth(
+  providerName: string,
+  provider: Record<string, unknown>,
+): Promise<ModelDiscoveryAuth> {
+  let tempDir: string | undefined;
+  try {
+    tempDir = mkdtempSync(join(tmpdir(), "pi-web-model-discovery-"));
+    const modelsPath = join(tempDir, "models.json");
+    const discoveryModelId = "__pi_web_model_discovery__";
+    writeFileSync(modelsPath, JSON.stringify({
+      providers: {
+        [providerName]: {
+          ...provider,
+          models: [{ id: discoveryModelId }],
+        },
+      },
+    }, null, 2), "utf8");
+
+    const modelRuntime = await ModelRuntime.create({ modelsPath });
+    const loadError = modelRuntime.getError();
+    if (loadError) throw new Error(loadError);
+    const model = modelRuntime.getModel(providerName, discoveryModelId);
+    if (!model) throw new Error(`Unable to load provider "${providerName}"`);
+
+    const resolved = await modelRuntime.getAuth(model);
+    if (resolved) {
+      return {
+        apiKey: resolved.auth.apiKey,
+        headers: stringRecord(resolved.auth.headers),
+      };
+    }
+
+    return {
+      headers: stringRecord(modelRuntime.getCompatibilityRequestConfig(model).headers),
+    };
+  } finally {
+    if (tempDir) rmSync(tempDir, { recursive: true, force: true });
+  }
+}