import { describe, expect, it } from "vitest";
import { parseRuntimeConfig } from "../src/config/index.js";

describe("parseRuntimeConfig", () => {
  it("returns defaults when env values are missing", () => {
    expect(parseRuntimeConfig({})).toEqual({
      mode: "development",
      port: 3000,
    });
  });

  it("parses valid runtime mode and port", () => {
    expect(
      parseRuntimeConfig({
        RUNTIME_MODE: "production",
        HTTP_PORT: "8080",
      }),
    ).toEqual({
      mode: "production",
      port: 8080,
    });
  });

  it("normalizes mode casing and surrounding whitespace", () => {
    expect(
      parseRuntimeConfig({
        RUNTIME_MODE: "  PrOdUcTiOn  ",
        HTTP_PORT: " 8081 ",
      }),
    ).toEqual({
      mode: "production",
      port: 8081,
    });
  });

  it("rejects invalid runtime mode", () => {
    expect(() =>
      parseRuntimeConfig({
        RUNTIME_MODE: "staging",
      }),
    ).toThrow(/Invalid RUNTIME_MODE/);
  });

  it("rejects invalid http port", () => {
    expect(() =>
      parseRuntimeConfig({
        HTTP_PORT: "0",
      }),
    ).toThrow(/Invalid HTTP_PORT/);

    expect(() =>
      parseRuntimeConfig({
        HTTP_PORT: "not-a-number",
      }),
    ).toThrow(/Invalid HTTP_PORT/);

    expect(() =>
      parseRuntimeConfig({
        HTTP_PORT: "65536",
      }),
    ).toThrow(/Invalid HTTP_PORT/);

    expect(() =>
      parseRuntimeConfig({
        HTTP_PORT: "42.5",
      }),
    ).toThrow(/Invalid HTTP_PORT/);
  });
});