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

import { readFlash, withFlash } from "@/lib/admin-feedback";

describe("withFlash", () => {
  it("returns the plain path when there are no messages", () => {
    expect(withFlash("/admin/smtp", {})).toBe("/admin/smtp");
  });

  it("appends a success message", () => {
    expect(withFlash("/admin/smtp", { success: "Saved." })).toBe("/admin/smtp?success=Saved.");
  });

  it("appends an error message", () => {
    expect(withFlash("/admin/smtp", { error: "Nope." })).toBe("/admin/smtp?error=Nope.");
  });

  it("appends both and url-encodes values", () => {
    const result = withFlash("/admin/smtp", { success: "a b", error: "x&y" });
    const params = new URL(result, "http://local").searchParams;
    expect(params.get("success")).toBe("a b");
    expect(params.get("error")).toBe("x&y");
  });
});

describe("readFlash", () => {
  it("reads success and error from resolved search params", () => {
    expect(readFlash({ success: "ok", error: "bad" })).toEqual({ success: "ok", error: "bad" });
  });

  it("returns undefined fields when params are missing", () => {
    expect(readFlash(undefined)).toEqual({ success: undefined, error: undefined });
    expect(readFlash(null)).toEqual({ success: undefined, error: undefined });
    expect(readFlash({})).toEqual({ success: undefined, error: undefined });
  });
});