import { useState } from "react";
import { render, screen, within } from "@testing-library/react";
import userEvent from "@testing-library/user-event";
import { describe, expect, it, vi } from "vitest";
import { readdirSync, readFileSync, statSync } from "node:fs";
import { join } from "node:path";
import { ActiveHistoryTabs, countOf, type EntityLifecycleTab } from "./active-history-tabs";

function Harness({ onValueChange }: { onValueChange?: (value: EntityLifecycleTab) => void }) {
  const [value, setValue] = useState<EntityLifecycleTab>("active");
  return (
    <ActiveHistoryTabs
      value={value}
      onValueChange={(next) => {
        setValue(next);
        onValueChange?.(next);
      }}
      activeCount={1}
      historyCount={0}
      toolbar={<button type="button">Filter</button>}
    >
      {{ active: <p>Liste aktiv</p>, history: <p>Liste Historie</p> }}
    </ActiveHistoryTabs>
  );
}

describe("ActiveHistoryTabs (spec 10.4)", () => {
  it("ActiveHistoryTabs shows the counts and renders the matching panel", async () => {
    const user = userEvent.setup();
    const onValueChange = vi.fn();
    render(<Harness onValueChange={onValueChange} />);

    const active = screen.getByRole("tab", { name: "Aktiv (1)" });
    const history = screen.getByRole("tab", { name: "Historie (0)" });
    expect(active).toHaveAttribute("aria-selected", "true");
    expect(screen.getByRole("tabpanel", { name: "Aktiv (1)" })).toHaveTextContent("Liste aktiv");
    expect(screen.queryByText("Liste Historie")).not.toBeInTheDocument();

    await user.click(history);
    expect(onValueChange).toHaveBeenLastCalledWith("history");
    expect(history).toHaveAttribute("aria-selected", "true");
    expect(screen.getByRole("tabpanel", { name: "Historie (0)" })).toHaveTextContent("Liste Historie");
    expect(screen.queryByText("Liste aktiv")).not.toBeInTheDocument();

    await user.keyboard("{ArrowLeft}");
    expect(onValueChange).toHaveBeenLastCalledWith("active");
    expect(screen.getByRole("tabpanel")).toHaveTextContent("Liste aktiv");
  });

  it("leaves the counts out while they are unknown", () => {
    render(
      <ActiveHistoryTabs value="active" onValueChange={() => {}}>
        {{ active: null, history: null }}
      </ActiveHistoryTabs>,
    );
    expect(screen.getByRole("tab", { name: "Aktiv" })).toBeInTheDocument();
    expect(screen.getByRole("tab", { name: "Historie" })).toBeInTheDocument();
  });

  it("puts the toolbar next to the tabs, outside the panels", () => {
    render(<Harness />);
    const filter = screen.getByRole("button", { name: "Filter" });
    expect(within(screen.getByRole("tabpanel")).queryByRole("button", { name: "Filter" })).toBeNull();
    expect(screen.getByRole("tablist").parentElement).toContainElement(filter);
  });

  it("arrow keys switch at once here, because both panels filter data that is already loaded", async () => {
    const user = userEvent.setup();
    render(<Harness />);
    await user.click(screen.getByRole("tab", { name: "Aktiv (1)" }));
    await user.keyboard("{ArrowRight}");
    expect(screen.getByRole("tab", { name: "Historie (0)" })).toHaveAttribute("aria-selected", "true");
    expect(screen.getByRole("tabpanel")).toHaveTextContent("Liste Historie");
  });

  it("toolbarAlign end pushes the toolbar to the far right of the row", () => {
    render(
      <ActiveHistoryTabs
        value="active"
        onValueChange={() => {}}
        toolbar={<button type="button">Neue Rolle</button>}
        toolbarAlign="end"
      >
        {{ active: null, history: null }}
      </ActiveHistoryTabs>,
    );
    const wrapper = screen.getByRole("button", { name: "Neue Rolle" }).parentElement as HTMLElement;
    expect(wrapper.className.split(/\s+/)).toContain("ml-auto");
    expect(screen.getByRole("tablist").parentElement).toContainElement(wrapper);
  });

  it("a heading opens the row before the tabs, the tabs sit on the right", () => {
    render(
      <ActiveHistoryTabs
        value="active"
        onValueChange={() => {}}
        heading={<h2>Lagerbehälter</h2>}
      >
        {{ active: null, history: null }}
      </ActiveHistoryTabs>,
    );
    const heading = screen.getByRole("heading", { name: "Lagerbehälter" });
    const list = screen.getByRole("tablist");
    expect(heading.compareDocumentPosition(list) & Node.DOCUMENT_POSITION_FOLLOWING).toBeTruthy();
    expect(list.parentElement).toContainElement(heading);
    expect(list.className.split(/\s+/)).toContain("ml-auto");
  });

  it("the chips are 44 px high on touch and compact only with a fine pointer", () => {
    render(<Harness />);
    for (const tab of screen.getAllByRole("tab")) {
      const classes = tab.className.split(/\s+/);
      expect(classes).toContain("h-11");
      expect(classes).toContain("pointer-fine:h-9");
    }
  });

  it("countOf counts only loaded data: no number while loading or after a failed first load", () => {
    expect(countOf(undefined, [])).toBeUndefined();
    expect(countOf([], [])).toBe(0);
    expect(countOf([1, 2, 3], [1, 3])).toBe(2);
  });

  it("every list passes its counts through countOf, so a failed load never says (0)", () => {
    const src = join(__dirname, "..");
    const files = (function walk(dir: string): string[] {
      return readdirSync(dir).flatMap((name) => {
        const path = join(dir, name);
        if (statSync(path).isDirectory()) return walk(path);
        return /\.tsx$/.test(name) && !/\.spec\./.test(name) ? [path] : [];
      });
    })(src);
    const users = files.filter((file) => /<ActiveHistoryTabs\b/.test(readFileSync(file, "utf8")));
    expect(users.length).toBeGreaterThanOrEqual(10);
    const wrong = users.filter((file) => {
      const text = readFileSync(file, "utf8");
      const counts = [...text.matchAll(/(?:active|history)Count=\{([^}]*)\}/g)].map((match) => match[1]);
      return counts.length !== 2 || counts.some((expression) => !/^countOf\(/.test(expression.trim()));
    });
    expect(wrong).toEqual([]);
  });
});