import { describe, expect, it } from 'vitest';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import { createTemplateStore } from './templates';

// The project root is the parent of server/ (mirrors how server/index.ts and
// server/regions.test.ts locate it via import.meta.url).
const root = fileURLToPath(new URL('..', import.meta.url));
const templatesDir = path.join(root, 'presets', 'templates');

const store = createTemplateStore(templatesDir);

/** A well-formed ISO_A3 country code: exactly three uppercase letters. */
function isIsoA3(code: string): boolean {
  return /^[A-Z]{3}$/.test(code);
}

describe('era templates store (v0.31.0, #52)', () => {
  it('the manifest lists exactly the three era templates', () => {
    const meta = store.listMeta();
    expect(meta).toHaveLength(3);
    const ids = meta.map((m) => m.id);
    expect(ids).toEqual(['ww2', 'present', 'near-future']);
    for (const m of meta) {
      expect(m.id).toBeTruthy();
      expect(m.name).toBeTruthy();
      expect(typeof m.year).toBe('number');
      expect(m.eraDescription).toBeTruthy();
    }
  });

  it('each template file loads and is well-formed', () => {
    for (const m of store.listMeta()) {
      const t = store.get(m.id);
      expect(t, `template ${m.id} should load`).not.toBeNull();
      const tpl = t as NonNullable<typeof t>;
      expect(tpl.id).toBe(m.id);
      expect(tpl.name).toBe(m.name);
      expect(tpl.year).toBe(m.year);
      expect(tpl.eraDescription).toBeTruthy();
      // suggested powers: non-empty, each a named power with an ISO_A3 core region + note.
      expect(tpl.suggestedPowers.length).toBeGreaterThan(0);
      for (const p of tpl.suggestedPowers) {
        expect(p.name).toBeTruthy();
        expect(isIsoA3(p.region)).toBe(true);
        expect(p.note).toBeTruthy();
      }
      // tensions: a non-empty list of non-empty strings.
      expect(tpl.tensions.length).toBeGreaterThan(0);
      for (const s of tpl.tensions) expect(typeof s).toBe('string');
      for (const s of tpl.tensions) expect(s.trim()).not.toBe('');
    }
  });

  it('get returns null for an unknown id', () => {
    expect(store.get('does-not-exist')).toBeNull();
    expect(store.get('')).toBeNull();
  });
});