/**
 * lib/fs — assertWebProjectRoot guard tests.
 *
 * Reproduces the ba-develop incident: a frontend scaffold received the REPO
 * ROOT as projectPath, wrote into the backend's src/, and a subagent then
 * `rm -rf`'d the colliding src/. The guard must REFUSE a .NET/backend/repo root
 * BEFORE any write, so that collision can never happen. Every frontend scaffold
 * (scaffold-component/api-client/routes/layout/theme/ui-primitives) calls this
 * before its write loop.
 */
import { describe, it, expect, beforeEach, afterEach } from 'vitest';
import { mkdtempSync, mkdirSync, writeFileSync, rmSync } from 'node:fs';
import { tmpdir } from 'node:os';
import path from 'node:path';
import { assertWebProjectRoot, FileSystemError } from '../fs.js';

let root: string;

beforeEach(() => {
  root = mkdtempSync(path.join(tmpdir(), 'assert-web-root-'));
});
afterEach(() => {
  rmSync(root, { recursive: true, force: true });
});

function dir(...segs: string[]): string {
  const p = path.join(root, ...segs);
  mkdirSync(p, { recursive: true });
  return p;
}
function file(rel: string, content = ''): void {
  const p = path.join(root, rel);
  mkdirSync(path.dirname(p), { recursive: true });
  writeFileSync(p, content, 'utf-8');
}

describe('assertWebProjectRoot', () => {
  it('accepts a real React web app root (package.json, no .sln, no backend src)', () => {
    const web = dir('web', 'test-web');
    writeFileSync(path.join(web, 'package.json'), '{"name":"test-web"}', 'utf-8');
    mkdirSync(path.join(web, 'src', 'pages'), { recursive: true });
    expect(() => assertWebProjectRoot(web)).not.toThrow();
  });

  it('REJECTS a .NET solution / repo root (has a .sln) even with a root package.json', () => {
    file('Test.sln', '');
    file('package.json', '{}');
    expect(() => assertWebProjectRoot(root)).toThrow(FileSystemError);
    expect(() => assertWebProjectRoot(root)).toThrow(/\.sln|repo root/i);
  });

  it('REJECTS a backend root whose src/ holds .NET projects (the exact incident shape)', () => {
    dir('src', 'Test.Domain');
    dir('src', 'Test.Application');
    dir('src', 'Test.Infrastructure');
    dir('src', 'Test.Api');
    file('package.json', '{}'); // present at root, but src/ is the backend → still refused
    const web = dir('web', 'test-web');
    writeFileSync(path.join(web, 'package.json'), '{"name":"test-web"}', 'utf-8');
    expect(() => assertWebProjectRoot(root)).toThrow(FileSystemError);
    expect(() => assertWebProjectRoot(root)).toThrow(/backend|Test\.(Domain|Api)/i);
  });

  it('REJECTS a backend root whose src/ holds a flat .csproj', () => {
    file('src/Test.Api.csproj', '<Project/>');
    file('package.json', '{}');
    expect(() => assertWebProjectRoot(root)).toThrow(/backend|\.csproj/i);
  });

  it('accepts the CORRECT web app subdir even when the repo root is a backend', () => {
    // The fix: ba-develop must pass web/test-web (this), not the repo root.
    dir('src', 'Test.Domain');
    file('Test.sln', '');
    const web = dir('web', 'test-web');
    writeFileSync(path.join(web, 'package.json'), '{"name":"test-web"}', 'utf-8');
    mkdirSync(path.join(web, 'src'), { recursive: true });
    expect(() => assertWebProjectRoot(web)).not.toThrow();
  });

  it('REJECTS a directory with no package.json (not a web root)', () => {
    const empty = dir('some-empty-dir');
    expect(() => assertWebProjectRoot(empty)).toThrow(/package\.json/i);
  });

  it('REJECTS a non-existent path', () => {
    expect(() => assertWebProjectRoot(path.join(root, 'does-not-exist'))).toThrow(/does not exist|unreadable/i);
  });
});