import { beforeEach, describe, expect, it, vi } from "vitest";

const poolConstructor = vi.hoisted(() => vi.fn());
const betterAuthMock = vi.hoisted(() => vi.fn());
const drizzleAdapterMock = vi.hoisted(() => vi.fn());
const serveMock = vi.hoisted(() => vi.fn());
const processOnSpy = vi.hoisted(() => vi.fn());

vi.mock("pg", () => ({ Pool: poolConstructor }));
vi.mock("better-auth", () => ({ betterAuth: betterAuthMock }));
vi.mock("better-auth/adapters/drizzle", () => ({ drizzleAdapter: drizzleAdapterMock }));
vi.mock("@hono/node-server", () => ({ serve: serveMock }));

describe("Ekklesia API import safety", () => {
  const originalEnv = { ...process.env };
  const originalProcessOn = process.on.bind(process);

  beforeEach(() => {
    poolConstructor.mockClear();
    betterAuthMock.mockClear();
    drizzleAdapterMock.mockClear();
    serveMock.mockClear();
    processOnSpy.mockClear();
    for (const key of Object.keys(process.env)) {
      if (!(key in originalEnv)) {
        delete process.env[key];
      }
    }
    process.env = { ...originalEnv };
    process.on = originalProcessOn;
  });

  it("does not construct a database pool, Better Auth, or an HTTP server merely by importing the app factory", async () => {
    await import("../src/app.js");

    expect(poolConstructor).not.toHaveBeenCalled();
    expect(betterAuthMock).not.toHaveBeenCalled();
    expect(serveMock).not.toHaveBeenCalled();
  });

  it("does not construct a database pool, Better Auth, or an HTTP server merely by importing configuration", async () => {
    await import("../src/config.js");

    expect(poolConstructor).not.toHaveBeenCalled();
    expect(betterAuthMock).not.toHaveBeenCalled();
    expect(serveMock).not.toHaveBeenCalled();
  });

  it("does not read environment variables, connect to PostgreSQL, construct Better Auth, start a server, or install signal handlers merely by importing the executable server module", async () => {
    // Deliberately leave every runtime-required environment variable unset. If importing this
    // module performed any runtime composition, missing configuration would throw here.
    delete process.env.DATABASE_URL;
    delete process.env.EKKLESIA_IDENTITY_SECRET;
    delete process.env.EKKLESIA_IDENTITY_BASE_URL;
    delete process.env.EKKLESIA_IDENTITY_TRUSTED_ORIGINS;
    const onSpy = vi.spyOn(process, "on").mockImplementation(processOnSpy);

    await expect(import("../src/server.js")).resolves.toBeDefined();

    expect(poolConstructor).not.toHaveBeenCalled();
    expect(betterAuthMock).not.toHaveBeenCalled();
    expect(drizzleAdapterMock).not.toHaveBeenCalled();
    expect(serveMock).not.toHaveBeenCalled();
    expect(processOnSpy).not.toHaveBeenCalled();
    onSpy.mockRestore();
  });

  it("exposes startApi and main as explicit functions without invoking them at import time", async () => {
    const module = await import("../src/server.js");

    expect(typeof module.startApi).toBe("function");
    expect(typeof module.main).toBe("function");
    expect(serveMock).not.toHaveBeenCalled();
  });
});