// @vitest-environment happy-dom
import { afterEach, describe, expect, it, vi } from "vitest";

import { createSpawnForm, type SpawnFormHandle, type SpawnFormValues } from "./spawnForm.js";

/** Stubs fetch so `/api/info` only resolves once `resolveInfo()` is called —
 * everything else (names, projects, gitroot) answers immediately with an
 * empty/default body. Lets a test pick a preset (or type a custom command)
 * mid-flight, then observe what the late `/api/info` resolution does to it. */
function stubDeferredInfo(): { resolveInfo: () => void } {
  let releaseInfo: () => void = () => {};
  const infoGate = new Promise<void>((resolve) => {
    releaseInfo = resolve;
  });
  vi.stubGlobal(
    "fetch",
    vi.fn(async (input: RequestInfo | URL) => {
      const url = String(input);
      if (url.includes("/api/info")) {
        await infoGate;
        return new Response(
          JSON.stringify({
            hostname: "h",
            version: "0",
            home_dir: "/home/user",
            presets: [
              { id: "claude", label: "Claude", command: "claude" },
              { id: "fish", label: "Fish", command: "fish" },
              { id: "custom", label: "Custom…", command: "" },
            ],
          }),
          { status: 200 },
        );
      }
      if (url.includes("/api/names")) {
        return new Response(JSON.stringify({ names: ["amber-fox"] }), { status: 200 });
      }
      return new Response(JSON.stringify([]), { status: 200 });
    }),
  );
  return { resolveInfo: releaseInfo };
}

describe("spawnForm preset selection vs. late /api/info (#76)", () => {
  let handle: SpawnFormHandle | null = null;

  afterEach(() => {
    handle?.destroy();
    handle = null;
    vi.unstubAllGlobals();
  });

  async function drain(): Promise<void> {
    for (let i = 0; i < 40; i++) await Promise.resolve();
  }

  it("keeps an operator-picked tile after /api/info resolves late", async () => {
    const { resolveInfo } = stubDeferredInfo();
    let values: SpawnFormValues | undefined;
    handle = createSpawnForm({ onChange: (v) => (values = v), onSuccess() {} });
    const form = handle.el;
    document.body.appendChild(form);
    await drain();

    // Fallback presets are up; the operator picks "zsh" before /api/info lands.
    const zshTile = [...form.querySelectorAll<HTMLButtonElement>(".tile")].find(
      (t) => t.dataset.id === "zsh",
    )!;
    zshTile.click();
    expect(zshTile.classList.contains("is-active")).toBe(true);

    // /api/info lands late with a preset list that doesn't even include "zsh".
    resolveInfo();
    await drain();

    // The operator's pick must not be discarded back to the new list's first
    // entry — `onChange` only starts firing once the initial load settles
    // (`ready`), which happens right here, so this is the first place the
    // published command is observable.
    expect(values?.command).toBe("zsh");
  });

  it("keeps an operator-typed custom command after /api/info resolves late", async () => {
    const { resolveInfo } = stubDeferredInfo();
    let values: SpawnFormValues | undefined;
    handle = createSpawnForm({ onChange: (v) => (values = v), onSuccess() {} });
    const form = handle.el;
    document.body.appendChild(form);
    await drain();

    const customTile = [...form.querySelectorAll<HTMLButtonElement>(".tile")].find(
      (t) => t.dataset.id === "custom",
    )!;
    customTile.click();
    const cmdRaw = form.querySelector<HTMLInputElement>(".cmd-raw")!;
    cmdRaw.value = "htop";
    cmdRaw.dispatchEvent(new Event("input"));

    resolveInfo();
    await drain();

    expect(values?.command).toBe("htop");
    expect(cmdRaw.value).toBe("htop");
  });

  it("still applies the real presets' first entry when the operator never touched the command", async () => {
    const { resolveInfo } = stubDeferredInfo();
    let values: SpawnFormValues | undefined;
    handle = createSpawnForm({ onChange: (v) => (values = v), onSuccess() {} });
    const form = handle.el;
    document.body.appendChild(form);
    await drain();

    resolveInfo();
    await drain();

    // Untouched: the refined preset list is still free to settle the command.
    expect(values?.command).toBe("claude");
    const fishTile = [...form.querySelectorAll<HTMLButtonElement>(".tile")].find(
      (t) => t.dataset.id === "fish",
    );
    expect(fishTile).toBeDefined();
  });
});