/// <reference types="node" />

import { beforeEach, afterEach, describe, expect, test } from "vitest";
import {
  existsSync,
  mkdtempSync,
  readFileSync,
  rmSync,
  writeFileSync,
} from "node:fs";
import { join } from "node:path";
import { tmpdir } from "node:os";

import { SettingsService } from "../../src/services/settings";

/**
 * Tests for SettingsService persistence and migration behavior.
 */
describe("SettingsService", () => {
  let testDir: string;
  let settingsPath: string;

  beforeEach(() => {
    testDir = mkdtempSync(join(tmpdir(), "xo-cli-settings-test-"));
    settingsPath = join(testDir, ".wallet");
  });

  afterEach(() => {
    rmSync(testDir, { recursive: true, force: true });
  });

  test("returns defaults when settings file does not exist", () => {
    const settings = new SettingsService(settingsPath);

    expect(settings.getDefaultMnemonic()).toBeUndefined();
    expect(settings.getCurrency()).toBe("USD");
    expect(settings.getSettings()).toEqual({ currency: "USD" });
    expect(existsSync(settingsPath)).toBe(false);
  });

  test("migrates legacy .wallet plaintext mnemonic to JSON", () => {
    writeFileSync(settingsPath, "mnemonic-legacy", "utf8");

    const settings = new SettingsService(settingsPath);

    expect(settings.getDefaultMnemonic()).toBe("mnemonic-legacy");
    expect(settings.getCurrency()).toBe("USD");

    const persisted = JSON.parse(readFileSync(settingsPath, "utf8")) as {
      "default-mnemonic"?: string;
      currency: string;
    };
    expect(persisted).toEqual({
      "default-mnemonic": "mnemonic-legacy",
      currency: "USD",
    });
  });

  test("normalizes and persists currency and default-mnemonic", () => {
    const settings = new SettingsService(settingsPath);

    settings.setDefaultMnemonic("  mnemonic-primary  ");
    settings.setCurrency("aud");

    expect(settings.getSettings()).toEqual({
      "default-mnemonic": "mnemonic-primary",
      currency: "AUD",
    });

    const persisted = JSON.parse(readFileSync(settingsPath, "utf8")) as {
      "default-mnemonic"?: string;
      currency: string;
    };
    expect(persisted).toEqual({
      "default-mnemonic": "mnemonic-primary",
      currency: "AUD",
    });
  });

  test("emits settings-updated events on setting changes", () => {
    const settings = new SettingsService(settingsPath);
    const events: Array<{ key: string; value: string | undefined }> = [];

    settings.on("settings-updated", (event) => {
      events.push({ key: event.key, value: event.value });
    });

    settings.setCurrency("cad");
    settings.setDefaultMnemonic("mnemonic-blue");

    expect(events).toEqual([
      { key: "currency", value: "CAD" },
      { key: "default-mnemonic", value: "mnemonic-blue" },
    ]);
  });
});