import type { ConfigService } from "@nestjs/config";
import { describe, expect, it, vi } from "vitest";
import { EmexService } from "./emex.service";

// ConfigService.get(key, default) returns the raw ENV STRING (NestJS does not
// coerce <number> generics at runtime). These tests guard the regression where a
// string port range made the proxy-port arithmetic do string concat
// (45 + "10001" = "4510001"), producing an out-of-range port that crashed the
// whole app with undici "Invalid URL" at construction time.
function makeConfig(overrides: Record<string, string>): ConfigService {
  return {
    get: vi.fn((key: string, def?: unknown) =>
      Object.hasOwn(overrides, key) ? overrides[key] : def,
    ),
  } as unknown as ConfigService;
}

const browser = {} as never;
const redis = { set: vi.fn() } as never;
const posthog = {} as never;
const proxyTelemetry = { record: vi.fn() } as never;
const proxyHealth = {
  isFloxyDown: vi.fn(() => false),
  reportFloxyFailure: vi.fn(),
  reportFloxySuccess: vi.fn(),
} as never;

describe("EmexService proxy-port coercion (regression)", () => {
  it("does not throw 'Invalid URL' when ports arrive as strings over a real range", () => {
    const config = makeConfig({
      EMEX_USE_PROXY: "true",
      EMEX_PROXY_HOST: "74.81.81.81",
      EMEX_PROXY_PORT_START: "10001",
      EMEX_PROXY_PORT_END: "10099",
    });
    // Pre-fix: threw "Invalid URL" here (port "4510001" > 65535).
    expect(
      () => new EmexService(config, browser, redis, posthog, proxyTelemetry, proxyHealth),
    ).not.toThrow();
  });

  it("constructs with a single-port range (string env)", () => {
    const config = makeConfig({
      EMEX_USE_PROXY: "true",
      EMEX_PROXY_PORT_START: "823",
      EMEX_PROXY_PORT_END: "823",
    });
    expect(
      () => new EmexService(config, browser, redis, posthog, proxyTelemetry, proxyHealth),
    ).not.toThrow();
  });

  it("falls back to a valid default when the port env is garbage", () => {
    const config = makeConfig({
      EMEX_USE_PROXY: "true",
      EMEX_PROXY_PORT_START: "not-a-number",
      EMEX_PROXY_PORT_END: "999999",
    });
    expect(
      () => new EmexService(config, browser, redis, posthog, proxyTelemetry, proxyHealth),
    ).not.toThrow();
  });

  it("constructs cleanly with the proxy disabled", () => {
    const config = makeConfig({ EMEX_USE_PROXY: "false" });
    expect(
      () => new EmexService(config, browser, redis, posthog, proxyTelemetry, proxyHealth),
    ).not.toThrow();
  });
});