// @vitest-environment jsdom
//
// `x` selects the walked item and Esc clears, in a list that takes a selection (a playlist's rows).
// Its own file: listNav keeps module state.
import { useRef } from "react";
import { afterEach, describe, expect, it, vi } from "vitest";
import { cleanup, render, screen, waitFor } from "@testing-library/react";
import { followRemoval, navItemAttrs, useListNav, type NavSelection } from "./listNav";
import { useActiveScopes } from "./keymap";

afterEach(cleanup);

function Rows({
  selection,
  onDelete,
  rows = 3,
}: {
  selection?: NavSelection;
  onDelete?: (index: number) => void;
  rows?: number;
}) {
  const ref = useRef<HTMLDivElement>(null);
  useListNav(ref, { enabled: true, selection, onDelete });
  return (
    <div ref={ref}>
      {Array.from({ length: rows }, (_, i) => (
        <div key={i} {...navItemAttrs(i)} data-testid={`r${i}`}>
          <button data-testid={`r${i}-action`}>action</button>
          <input data-testid={`r${i}-input`} />
          <input type="checkbox" data-testid={`r${i}-box`} />
        </div>
      ))}
    </div>
  );
}

function Scopes() {
  return <output data-testid="scopes">{useActiveScopes().join(" ")}</output>;
}

function press(key: string, init: KeyboardEventInit = {}): KeyboardEvent {
  const e = new KeyboardEvent("keydown", { key, bubbles: true, cancelable: true, ...init });
  (document.activeElement ?? document.body).dispatchEvent(e);
  return e;
}

const selection = (cleared = true) => ({
  toggle: vi.fn<(index: number) => void>(),
  clear: vi.fn(() => cleared),
  removeSelected: vi.fn(() => false),
});

describe("useListNav · selecting", () => {
  it("toggles the walked item on x", () => {
    const s = selection();
    render(<Rows selection={s} />);
    press("j");
    press("j");
    const e = press("x");
    expect(s.toggle).toHaveBeenCalledExactlyOnceWith(1);
    expect(e.defaultPrevented).toBe(true);
  });

  it("toggles the item a control inside it holds the focus for", () => {
    const s = selection();
    render(<Rows selection={s} />);
    screen.getByTestId("r2-action").focus();
    press("x");
    expect(s.toggle).toHaveBeenCalledExactlyOnceWith(2);
  });

  it("goes on answering with the focus on the row's box, where a click leaves it", () => {
    const s = selection();
    render(<Rows selection={s} />);
    screen.getByTestId("r1-box").focus();
    press("x");
    expect(s.toggle).toHaveBeenCalledExactlyOnceWith(1);
    press("j");
    expect(document.activeElement).toBe(screen.getByTestId("r2"));
  });

  it("does nothing on x with no item under the keyboard", () => {
    const s = selection();
    render(<Rows selection={s} />);
    const e = press("x");
    expect(s.toggle).not.toHaveBeenCalled();
    expect(e.defaultPrevented).toBe(false);
  });

  it("types an x in a field instead of selecting", () => {
    const s = selection();
    render(<Rows selection={s} />);
    screen.getByTestId("r0-input").focus();
    press("x");
    expect(s.toggle).not.toHaveBeenCalled();
  });

  it("does not flip back and forth while x is held down", () => {
    const s = selection();
    render(<Rows selection={s} />);
    press("j");
    press("x");
    press("x", { repeat: true });
    expect(s.toggle).toHaveBeenCalledTimes(1);
  });

  it("clears on Esc wherever the focus is, and spends the key only when it cleared", () => {
    const s = selection();
    render(<Rows selection={s} />);
    expect(press("Escape").defaultPrevented).toBe(true);
    expect(s.clear).toHaveBeenCalledTimes(1);
    cleanup();

    const idle = selection(false);
    render(<Rows selection={idle} />);
    expect(press("Escape").defaultPrevented).toBe(false);
    expect(idle.clear).toHaveBeenCalledTimes(1);
  });

  it("takes the slot of an item that left by other hands, the focus on <body>", async () => {
    render(<Rows />);
    const leaving = screen.getByTestId("r1");
    followRemoval(screen.getByTestId("r1-action"));
    const list = leaving.parentElement!;
    list.removeChild(leaving);
    list.querySelector<HTMLElement>("[data-testid=r2]")!.setAttribute("data-nav-index", "1");
    await waitFor(() => expect(document.activeElement).toBe(screen.getByTestId("r2")));
  });

  it("goes on to the next row left, past what a selection took from above it", async () => {
    const s = selection();
    s.removeSelected.mockImplementation(() => {
      // As a commit does it, after the key's handler: the two rows go, and the ones left are numbered
      // from the top.
      queueMicrotask(() => {
        screen.getByTestId("r0").remove();
        screen.getByTestId("r1").remove();
        screen.getByTestId("r2").setAttribute("data-nav-index", "0");
        screen.getByTestId("r3").setAttribute("data-nav-index", "1");
      });
      return true;
    });
    render(<Rows selection={s} rows={4} />);
    const r2 = screen.getByTestId("r2");
    screen.getByTestId("r1-box").focus();
    press("Delete");
    await waitFor(() => expect(document.activeElement).toBe(r2));
  });

  it("leaves the focus where it is when something else took it meanwhile", async () => {
    render(<Rows />);
    const leaving = screen.getByTestId("r1");
    const other = screen.getByTestId("r0-input");
    other.focus();
    followRemoval(screen.getByTestId("r1-action"));
    leaving.remove();
    await new Promise((r) => setTimeout(r, 60));
    expect(document.activeElement).toBe(other);
  });

  it("has Delete go to the selection first, wherever the focus is", () => {
    const s = selection();
    s.removeSelected.mockReturnValue(true);
    const onDelete = vi.fn();
    render(<Rows selection={s} onDelete={onDelete} />);
    expect(press("Delete").defaultPrevented).toBe(true);
    expect(s.removeSelected).toHaveBeenCalledTimes(1);
    expect(onDelete).not.toHaveBeenCalled();
  });

  it("has Delete go on to the walked row when there is no selection", () => {
    const s = selection();
    const onDelete = vi.fn();
    render(<Rows selection={s} onDelete={onDelete} />);
    press("j");
    press("Delete");
    expect(onDelete).toHaveBeenCalledExactlyOnceWith(0);
  });

  it("leaves both keys alone in a list that takes no selection", () => {
    render(<Rows />);
    press("j");
    expect(press("x").defaultPrevented).toBe(false);
    expect(press("Escape").defaultPrevented).toBe(false);
  });

  it("lists the keys only over a list that takes a selection and has items", async () => {
    render(
      <>
        <Scopes />
        <Rows selection={selection()} />
      </>,
    );
    await waitFor(() => expect(screen.getByTestId("scopes").textContent).toContain("listSelect"));
    cleanup();
    render(
      <>
        <Scopes />
        <Rows />
      </>,
    );
    await waitFor(() => expect(screen.getByTestId("scopes").textContent).toContain("list"));
    expect(screen.getByTestId("scopes").textContent).not.toContain("listSelect");
  });
});