siftlode/frontend/src/components/ui/Combobox.dom.test.tsx

// @vitest-environment jsdom
//
// The universal combobox (chips + typed search field over the AnchoredPopover `combobox` mode). Covers
// chip removal, open-on-focus, client filter, toggling, Backspace-removes-last, the big-vocabulary cap,
// single-select, and the combobox ARIA the old hand-rolled control lacked (role=combobox, aria-expanded,
// and a virtual aria-activedescendant that keeps DOM focus on the input). i18n is key-passthrough; the
// floating-ui recipe (ActionMenu's): stub the two observers autoUpdate wires, wrap in a FloatingTree,
// and query the hidden surface with `{ hidden: true }` since jsdom never positions it.
import { describe, it, expect, vi, afterEach, beforeAll } from "vitest";
import { render, screen, fireEvent, cleanup } from "@testing-library/react";
import { FloatingTree } from "@floating-ui/react";

beforeAll(() => {
  class Stub {
    observe() {}
    unobserve() {}
    disconnect() {}
    takeRecords() {
      return [];
    }
  }
  globalThis.ResizeObserver ??= Stub as unknown as typeof ResizeObserver;
  globalThis.IntersectionObserver ??= Stub as unknown as typeof IntersectionObserver;
});

vi.mock("react-i18next", async (importOriginal) => {
  const actual = await importOriginal<typeof import("react-i18next")>();
  return { ...actual, useTranslation: () => ({ t: (k: string) => k }) };
});

import Combobox from "./Combobox";

afterEach(cleanup);

const OPTIONS = [
  { value: "Drama", count: 120 },
  { value: "Action", count: 90 },
  { value: "Comedy", count: 60 },
];

function wrap(ui: React.ReactElement) {
  return render(<FloatingTree>{ui}</FloatingTree>);
}

describe("Combobox", () => {
  it("renders selected values as removable chips and removes on ✕", () => {
    const onChange = vi.fn();
    wrap(<Combobox label="Genre" options={OPTIONS} selected={["Drama"]} onChange={onChange} />);
    expect(screen.getByText("Drama")).toBeTruthy();
    fireEvent.click(screen.getByRole("button", { name: "common.removeNamed" }));
    expect(onChange).toHaveBeenCalledWith([]); // Drama removed
  });

  it("exposes combobox ARIA: role=combobox, aria-expanded toggling, aria-controls when open", () => {
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={vi.fn()} />);
    const input = screen.getByRole("combobox");
    expect(input.getAttribute("aria-expanded")).toBe("false");
    expect(input.getAttribute("aria-controls")).toBeNull();
    fireEvent.focus(input);
    expect(input.getAttribute("aria-expanded")).toBe("true");
    // aria-controls now points at the listbox surface.
    const controls = input.getAttribute("aria-controls");
    expect(controls).toBeTruthy();
    expect(document.getElementById(controls!)?.getAttribute("role")).toBe("listbox");
  });

  it("focuses the input when the field chrome is pressed (merged ref, not a dead inputRef)", () => {
    // Regression: the input carried only floating-ui's ref, so `inputRef` stayed null. The field's
    // onMouseDown then preventDefault()-ed every press (its `e.target !== inputRef.current` guard was
    // always true) and its compensating inputRef.current?.focus() was a no-op → the box couldn't be
    // typed into with the mouse. A merged ref feeds the node to both, so pressing the chrome focuses it.
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={vi.fn()} />);
    const input = screen.getByRole("combobox");
    const field = input.parentElement as HTMLElement;
    expect(document.activeElement).not.toBe(input);
    fireEvent.mouseDown(field); // press the field padding, not the input itself
    expect(document.activeElement).toBe(input);
  });

  it("keeps the option list unmounted until the field is focused", () => {
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={vi.fn()} />);
    expect(screen.queryByRole("option", { hidden: true })).toBeNull();
    fireEvent.focus(screen.getByRole("combobox"));
    expect(screen.getAllByRole("option", { hidden: true }).length).toBe(3);
  });

  it("filters the options by the typed query", () => {
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={vi.fn()} />);
    const field = screen.getByRole("combobox");
    fireEvent.focus(field);
    fireEvent.change(field, { target: { value: "com" } });
    const items = screen.getAllByRole("option", { hidden: true });
    expect(items.length).toBe(1);
    expect(items[0]?.textContent).toContain("Comedy");
  });

  it("marks a selected option aria-selected and toggles another on", () => {
    const onChange = vi.fn();
    wrap(<Combobox label="Genre" options={OPTIONS} selected={["Drama"]} onChange={onChange} />);
    fireEvent.focus(screen.getByRole("combobox"));
    const drama = screen
      .getAllByRole("option", { hidden: true })
      .find((el) => el.textContent?.includes("Drama"));
    expect(drama?.getAttribute("aria-selected")).toBe("true");
    fireEvent.click(screen.getByText("Action")); // clicking the option's label toggles it on
    expect(onChange).toHaveBeenCalledWith(["Drama", "Action"]);
  });

  it("moves an aria-activedescendant on ArrowDown while DOM focus stays on the input", () => {
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={vi.fn()} />);
    const input = screen.getByRole("combobox");
    input.focus();
    fireEvent.focus(input);
    fireEvent.keyDown(input, { key: "ArrowDown" });
    // Virtual navigation: the input keeps DOM focus, the active option is referenced by id.
    expect(document.activeElement).toBe(input);
    expect(input.getAttribute("aria-activedescendant")).toBeTruthy();
  });

  it("removes the last chip on Backspace in an empty field", () => {
    const onChange = vi.fn();
    wrap(
      <Combobox
        label="Genre"
        options={OPTIONS}
        selected={["Drama", "Action"]}
        onChange={onChange}
      />,
    );
    fireEvent.keyDown(screen.getByRole("combobox"), { key: "Backspace" });
    expect(onChange).toHaveBeenCalledWith(["Drama"]); // last chip dropped
  });

  it("caps the rendered rows for a large vocabulary and shows a refine hint", () => {
    // A studio-sized list (hundreds) must not render every row — cap at 50 + a "N more" footer.
    const many = Array.from({ length: 60 }, (_, i) => ({ value: `Studio ${i}`, count: 60 - i }));
    wrap(<Combobox label="Studio" options={many} selected={[]} onChange={vi.fn()} />);
    fireEvent.focus(screen.getByRole("combobox"));
    expect(screen.getAllByRole("option", { hidden: true }).length).toBe(50);
    expect(screen.getByText("common.moreRefine")).toBeTruthy(); // 10 hidden behind search
  });

  it("Enter commits the pointer-highlighted option, not the arrow-active one", () => {
    // The visible highlight follows the pointer (hoverIndex); Enter must commit THAT row, not the bare
    // keyboard activeIndex — otherwise arrow-then-hover-then-Enter toggles a different option than shown.
    const onChange = vi.fn();
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={onChange} />);
    const input = screen.getByRole("combobox");
    input.focus();
    fireEvent.focus(input);
    fireEvent.keyDown(input, { key: "ArrowDown" }); // activeIndex → 0 (Drama)
    const action = screen
      .getAllByRole("option", { hidden: true })
      .find((el) => el.textContent?.includes("Action"))!;
    fireEvent.mouseMove(action); // hoverIndex → Action (the visibly highlighted row)
    fireEvent.keyDown(input, { key: "Enter" });
    expect(onChange).toHaveBeenCalledWith(["Action"]); // the highlighted (hovered) row, not Drama
  });

  it("Enter commits a hover-highlighted option even with no prior arrow key", () => {
    const onChange = vi.fn();
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={onChange} />);
    const input = screen.getByRole("combobox");
    input.focus();
    fireEvent.focus(input);
    const comedy = screen
      .getAllByRole("option", { hidden: true })
      .find((el) => el.textContent?.includes("Comedy"))!;
    fireEvent.mouseMove(comedy); // highlight via hover, activeIndex still null
    fireEvent.keyDown(input, { key: "Enter" });
    expect(onChange).toHaveBeenCalledWith(["Comedy"]); // no longer a silent no-op
  });

  it("async mode: controlled query + onQueryChange/onOpenChange, no client filter, selectedLabels chip", () => {
    const onQueryChange = vi.fn();
    const onOpenChange = vi.fn();
    const onChange = vi.fn();
    const serverOpts = [{ value: "id1", label: "Harry Potter", count: 8 }];
    wrap(
      <Combobox
        label="Collection"
        multiple={false}
        clientFilter={false}
        options={serverOpts}
        selected={["stored-id"]}
        selectedLabels={{ "stored-id": "Stored Collection" }}
        query="har"
        onQueryChange={onQueryChange}
        onOpenChange={onOpenChange}
        onChange={onChange}
      />,
    );
    // The selected value's option isn't in the (server-narrowed) list, so its chip uses selectedLabels.
    expect(screen.getByText("Stored Collection")).toBeTruthy();
    const input = screen.getByRole("combobox");
    fireEvent.focus(input);
    expect(onOpenChange).toHaveBeenCalledWith(true);
    fireEvent.change(input, { target: { value: "harr" } });
    expect(onQueryChange).toHaveBeenCalledWith("harr"); // controlled query propagates out
    // clientFilter=false: the single server option renders verbatim (not re-filtered against "har").
    const opts = screen.getAllByRole("option", { hidden: true });
    expect(opts.length).toBe(1);
    expect(opts[0]?.textContent).toContain("Harry Potter");
    fireEvent.click(screen.getByText("Harry Potter"));
    expect(onChange).toHaveBeenCalledWith(["id1"]); // single-select replaces
  });

  it("single-select: picking replaces the value and closes the list", () => {
    const onChange = vi.fn();
    wrap(
      <Combobox
        label="Collection"
        multiple={false}
        options={OPTIONS}
        selected={["Drama"]}
        onChange={onChange}
      />,
    );
    fireEvent.focus(screen.getByRole("combobox"));
    fireEvent.click(screen.getByText("Action"));
    expect(onChange).toHaveBeenCalledWith(["Action"]); // replaced, not appended
    expect(screen.getByRole("combobox").getAttribute("aria-expanded")).toBe("false"); // closed
  });

  // The typed query is discarded when the list closes. CHARACTERIZATION, not the regression guard:
  // the old effect-based clear satisfies these assertions too, because RTL wraps fireEvent in act()
  // and the passive effect has flushed by the time the value is read. What the move into the close
  // funnel actually fixed is measured by the next test, which the old shape fails. This one is here
  // because the behaviour is worth pinning: the list is for "find and pick", and a leftover filter
  // would hide everything worth seeing the next time it opens.
  it("discards the typed query when the list closes, so the next open shows everything", () => {
    wrap(<Combobox label="Genre" options={OPTIONS} selected={[]} onChange={vi.fn()} />);
    const input = screen.getByRole("combobox");
    fireEvent.focus(input);
    fireEvent.change(input, { target: { value: "com" } });
    expect(input).toHaveProperty("value", "com");
    expect(screen.queryByText("Drama")).toBeNull(); // filtered away

    fireEvent.keyDown(input, { key: "Escape" });
    expect(input.getAttribute("aria-expanded")).toBe("false");
    expect(input).toHaveProperty("value", "");

    fireEvent.focus(input);
    expect(screen.getByText("Drama")).toBeTruthy(); // the whole list is back
  });

  it("does not report a query change until something actually changes it", () => {
    // A clear driven by an effect on `open` fires at MOUNT too — `open` starts false — so a
    // controlled caller was told its own initial query had been cleared before the user touched
    // anything. Driving it from the close event instead means no event, no callback.
    const onQueryChange = vi.fn();
    const onOpenChange = vi.fn();
    wrap(
      <Combobox
        label="Collection"
        multiple={false}
        options={OPTIONS}
        selected={[]}
        onChange={vi.fn()}
        query="com"
        onQueryChange={onQueryChange}
        onOpenChange={onOpenChange}
        clientFilter={false}
      />,
    );
    expect(onQueryChange).not.toHaveBeenCalled();

    fireEvent.focus(screen.getByRole("combobox"));
    expect(onQueryChange).not.toHaveBeenCalled();
    fireEvent.click(screen.getByText("Action"));
    expect(onOpenChange).toHaveBeenLastCalledWith(false);
    expect(onQueryChange.mock.calls).toEqual([[""]]);
  });
});

// PageUp/PageDown (E11, owner request): the sidebar's channel filter and the Plex pickers run to
// hundreds of rows, and floating-ui's list navigation has only the arrows. jsdom has no layout, so a
// page is the fixed fallback of 10 rows; the measured page is pinned in lib/listPaging.
describe("Combobox · paging", () => {
  const rows = (disabled: number[] = []) =>
    Array.from({ length: 25 }, (_, i) => ({ value: `Row ${i}`, disabled: disabled.includes(i) }));
  const activeValue = (input: HTMLElement) =>
    document.getElementById(input.getAttribute("aria-activedescendant") ?? "")?.textContent;

  it("moves the active option a page at a time, stopping at both ends", () => {
    wrap(<Combobox label="Channel" options={rows()} selected={[]} onChange={vi.fn()} />);
    const input = screen.getByRole("combobox");
    input.focus();
    fireEvent.focus(input);
    expect(fireEvent.keyDown(input, { key: "PageDown" })).toBe(false); // the page does not scroll
    expect(activeValue(input)).toBe("Row 10");
    expect(document.activeElement).toBe(input);
    fireEvent.keyDown(input, { key: "PageDown" });
    fireEvent.keyDown(input, { key: "PageDown" });
    expect(activeValue(input)).toBe("Row 24"); // no wrap to the top
    fireEvent.keyDown(input, { key: "PageUp" });
    expect(activeValue(input)).toBe("Row 14");
  });

  it("never lands on a disabled option, and Enter commits where it landed", () => {
    const onChange = vi.fn();
    wrap(<Combobox label="Channel" options={rows([10])} selected={[]} onChange={onChange} />);
    const input = screen.getByRole("combobox");
    input.focus();
    fireEvent.focus(input);
    fireEvent.keyDown(input, { key: "PageDown" });
    fireEvent.keyDown(input, { key: "Enter" });
    expect(onChange).toHaveBeenCalledWith(["Row 11"]);
  });

  it("leaves the key alone while the list is closed", () => {
    wrap(<Combobox label="Channel" options={rows()} selected={[]} onChange={vi.fn()} />);
    expect(fireEvent.keyDown(screen.getByRole("combobox"), { key: "PageDown" })).toBe(true);
  });
});