feat: client config and version

Author: Transcript-Fetch-Admin

src/config.ts

@@ -0,0 +1,52 @@
+/** Client configuration resolution, shared by the client and its resources. */
+
+export const DEFAULT_BASE_URL = "https://transcriptfetch.com";
+export const ENV_API_KEY = "TRANSCRIPTFETCH_API_KEY";
+
+/** Options accepted by the {@link TranscriptFetch} constructor. */
+export interface ClientOptions {
+  /** Your API key. Falls back to the TRANSCRIPTFETCH_API_KEY environment variable. */
+  apiKey?: string;
+  /** Override the API origin. Defaults to https://transcriptfetch.com. */
+  baseUrl?: string;
+  /** Per-request timeout in milliseconds. Defaults to 30000. */
+  timeout?: number;
+  /** How many times to retry 429 and 5xx responses. Defaults to 2. */
+  maxRetries?: number;
+  /** Inject a custom fetch implementation (defaults to the global fetch). */
+  fetch?: typeof fetch;
+}
+
+export interface ResolvedConfig {
+  apiKey: string;
+  baseUrl: string;
+  timeout: number;
+  maxRetries: number;
+  fetch: typeof fetch;
+}
+
+/** Resolve user options into a complete config, reading env and applying defaults. */
+export function resolveConfig(options: ClientOptions = {}): ResolvedConfig {
+  const envKey = typeof process !== "undefined" ? process.env?.[ENV_API_KEY] : undefined;
+  const apiKey = options.apiKey ?? envKey;
+  if (!apiKey) {
+    throw new Error(
+      `No API key provided. Pass { apiKey } or set the ${ENV_API_KEY} environment variable.`,
+    );
+  }
+
+  const fetchImpl = options.fetch ?? globalThis.fetch;
+  if (typeof fetchImpl !== "function") {
+    throw new Error(
+      "global fetch is not available. Use Node 18+, or pass a fetch implementation via { fetch }.",
+    );
+  }
+
+  return {
+    apiKey,
+    baseUrl: (options.baseUrl ?? DEFAULT_BASE_URL).replace(/\/+$/, ""),
+    timeout: options.timeout ?? 30_000,
+    maxRetries: Math.max(0, options.maxRetries ?? 2),
+    fetch: fetchImpl,
+  };
+}

src/version.ts

@@ -0,0 +1,2 @@
+/** The SDK version, surfaced in the User-Agent header. Kept in sync with package.json. */
+export const VERSION = "0.1.0";