import { join } from 'path';
import { pathToFileURL } from 'url';
type Class<T> = new (...args: any[]) => T;
interface Service<T> {
defaultImpl: Class<T>;
override?: Class<T>;
}
const registry = new Map<string, Service<any>>();
const instances = new Map<string, unknown>();
async function tryLoadOverride<T>(key: string, overridePath: string): Promise<Class<T> | undefined> {
try {
const moduleUrl = pathToFileURL(overridePath).href;
const mod = await import(moduleUrl);
const override = mod[key.charAt(0).toUpperCase() + key.slice(1) + 'x'];
if (typeof override === 'function') {
return override as Class<T>;
}
} catch (error: any) {
// Ignore not-found errors and keep trying other paths; surface other errors for visibility
if (error?.code !== 'ERR_MODULE_NOT_FOUND' && error?.code !== 'MODULE_NOT_FOUND') {
console.warn(`Failed to load service override from ${overridePath}:`, error);
}
}
return undefined;
}
export async function registerService<T>(key: string, entry: Service<T>) {
// Try to load override immediately during registration
// Try multiple paths and file extensions in order
const serviceDirs = ['src/services', 'dist/services'];
const fileExts = ['.ts', '.js'];
const overrideFileName = key + 'x';
for (const serviceDir of serviceDirs) {
for (const fileExt of fileExts) {
const overridePath = join(process.cwd(), serviceDir, overrideFileName + fileExt);
const override = await tryLoadOverride<T>(key, overridePath);
if (override) {
entry.override = override;
break; // Found override, exit both loops
}
}
// If override was found, break out of outer loop too
if (entry.override) {
break;
}
}
registry.set(key, entry);
}
export function getService<T>(key: string): T {
if (instances.has(key)) {
return instances.get(key) as T;
}
const entry = registry.get(key);
if (!entry) throw new Error(`Service not registered for key: ${key.toString()}`);
// Use override if available, otherwise use default
const Impl = entry.override || entry.defaultImpl;
const instance = new Impl();
instances.set(key, instance);
return instance;
}
