/**
 * @file AgentInstructionsSettings.test.tsx
 * @description My agent instructions: a failed load shows the error with a
 * Retry (the editor stays locked, so a save cannot overwrite unloaded text)
 * and Retry unlocks it; Choose file puts a local file's text into the draft
 * without saving, and refuses one longer than the limit; "Applies to" names
 * only the installed, enabled tools the server says receive them.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

import { fireEvent, render, screen, waitFor } from "@testing-library/react";
import { beforeEach, describe, expect, it, vi } from "vitest";
import { AgentInstructionsSettings } from "../AgentInstructionsSettings";
import { api } from "../../../lib/api";
import { toast } from "../../../lib/toast";

vi.mock("../../../lib/api", async (importOriginal) => {
  const actual = await importOriginal<Record<string, unknown>>();
  return {
    ...actual,
    api: { me: { instructions: vi.fn(), saveInstructions: vi.fn() } },
  };
});
const aiTools = vi.hoisted(() => ({
  tools: [] as { id: string; label: string; installed: boolean; enabled: boolean }[],
}));
vi.mock("../../../hooks/useAiTools", () => ({ useAiTools: () => aiTools }));
vi.mock("../../../lib/toast", () => ({ toast: { success: vi.fn(), error: vi.fn() } }));

const instructions = vi.mocked(api.me.instructions);
const saveInstructions = vi.mocked(api.me.saveInstructions);
const editor = () => screen.getByRole("textbox") as HTMLTextAreaElement;
// jsdom's File has no text(); every browser AgentHub supports does.
const pick = (text: string, name = "rules.md") => {
  const file = Object.assign(new File([text], name, { type: "text/markdown" }), {
    text: () => Promise.resolve(text),
  });
  fireEvent.change(screen.getByTestId("agent-instructions-file"), { target: { files: [file] } });
};

describe("AgentInstructionsSettings", () => {
  beforeEach(() => {
    vi.clearAllMocks();
    aiTools.tools = [];
  });

  it("names only the installed, enabled tools that receive the instructions", async () => {
    aiTools.tools = [
      { id: "claude", label: "Claude Code", installed: true, enabled: true },
      { id: "codex", label: "Codex", installed: true, enabled: false },
      { id: "cursor", label: "Cursor CLI", installed: true, enabled: true },
    ];
    instructions.mockResolvedValue({ instructions: "", max: 100, tools: ["claude", "codex"] });
    render(<AgentInstructionsSettings />);
    expect(await screen.findByText("Claude Code")).toBeInTheDocument();
    expect(screen.getByText("Applies to")).toBeInTheDocument();
    expect(screen.queryByText("Codex")).toBeNull();
    expect(screen.queryByText("Cursor CLI")).toBeNull();
  });

  it("shows a failed load with Retry, and Retry unlocks the editor", async () => {
    instructions.mockRejectedValueOnce(new Error("HTTP 404"));
    render(<AgentInstructionsSettings />);
    expect(await screen.findByText(/HTTP 404/)).toBeInTheDocument();
    expect(editor()).toBeDisabled();

    instructions.mockResolvedValueOnce({ instructions: "# saved", max: 100, tools: [] });
    fireEvent.click(screen.getByRole("button", { name: /retry/i }));
    await waitFor(() => expect(editor()).not.toBeDisabled());
    expect(editor().value).toBe("# saved");
  });

  it("Choose file fills the draft without saving; Save sends it", async () => {
    instructions.mockResolvedValue({ instructions: "", max: 100, tools: [] });
    saveInstructions.mockResolvedValue({ instructions: "# from file", max: 100, tools: [] });
    render(<AgentInstructionsSettings />);
    await waitFor(() => expect(editor()).not.toBeDisabled());

    pick("# from file");
    await waitFor(() => expect(editor().value).toBe("# from file"));
    expect(saveInstructions).not.toHaveBeenCalled();

    fireEvent.click(screen.getByRole("button", { name: /^save$/i }));
    await waitFor(() => expect(saveInstructions).toHaveBeenCalledWith("# from file"));
  });

  it("refuses a file longer than the limit and keeps the draft", async () => {
    instructions.mockResolvedValue({ instructions: "keep", max: 5, tools: [] });
    render(<AgentInstructionsSettings />);
    await waitFor(() => expect(editor()).not.toBeDisabled());

    pick("way too long");
    await waitFor(() => expect(toast.error).toHaveBeenCalled());
    expect(editor().value).toBe("keep");
  });
});