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

import {
  resolvePanelTabKey,
  tabControlId,
  tabPanelId,
  tabPanelProps,
} from "./panelTabsUtils";

const TABS = ["button", "notification", "advanced"] as const;

describe("panel tab ids", () => {
  it("derives distinct, stable ids for the tab and its panel", () => {
    expect(tabControlId("cart", "button")).toBe("cart-tab-button");
    expect(tabPanelId("cart", "button")).toBe("cart-panel-button");
    expect(tabControlId("cart", "button")).not.toBe(
      tabPanelId("cart", "button"),
    );
  });

  it("namespaces ids per tablist so nested tablists never collide", () => {
    expect(tabControlId("cart", "backend")).not.toBe(
      tabControlId("cart-ajax", "backend"),
    );
  });

  it("wires the panel back to the tab that labels it", () => {
    expect(tabPanelProps("cart", "advanced")).toEqual({
      role: "tabpanel",
      id: "cart-panel-advanced",
      "aria-labelledby": "cart-tab-advanced",
    });
  });
});

describe("resolvePanelTabKey", () => {
  it("moves right and left along the tablist", () => {
    expect(resolvePanelTabKey("ArrowRight", "button", TABS)).toBe(
      "notification",
    );
    expect(resolvePanelTabKey("ArrowLeft", "notification", TABS)).toBe(
      "button",
    );
  });

  it("wraps at both ends", () => {
    expect(resolvePanelTabKey("ArrowRight", "advanced", TABS)).toBe("button");
    expect(resolvePanelTabKey("ArrowLeft", "button", TABS)).toBe("advanced");
  });

  it("jumps to the first and last tab with Home/End", () => {
    expect(resolvePanelTabKey("Home", "notification", TABS)).toBe("button");
    expect(resolvePanelTabKey("End", "notification", TABS)).toBe("advanced");
  });

  it("mirrors the horizontal arrows under RTL", () => {
    expect(resolvePanelTabKey("ArrowRight", "notification", TABS, true)).toBe(
      "button",
    );
    expect(resolvePanelTabKey("ArrowLeft", "notification", TABS, true)).toBe(
      "advanced",
    );
  });

  it("leaves Home/End unmirrored under RTL (they are positional, not directional)", () => {
    expect(resolvePanelTabKey("Home", "advanced", TABS, true)).toBe("button");
    expect(resolvePanelTabKey("End", "button", TABS, true)).toBe("advanced");
  });

  it("does not swallow vertical arrows — the panel must stay scrollable", () => {
    expect(resolvePanelTabKey("ArrowDown", "button", TABS)).toBeNull();
    expect(resolvePanelTabKey("ArrowUp", "button", TABS)).toBeNull();
  });

  it("leaves Enter/Space to the button's native activation", () => {
    expect(resolvePanelTabKey("Enter", "button", TABS)).toBeNull();
    expect(resolvePanelTabKey(" ", "button", TABS)).toBeNull();
  });

  it("treats an unknown current tab as the first tab rather than throwing", () => {
    expect(resolvePanelTabKey("ArrowRight", "does-not-exist", TABS)).toBe(
      "notification",
    );
  });

  it("returns null for an empty tablist", () => {
    expect(resolvePanelTabKey("ArrowRight", "button", [])).toBeNull();
  });
});