import { describe, it, expect, beforeEach, afterEach } from 'vitest';
import { mkdtempSync, rmSync } from 'fs';
import { tmpdir } from 'os';
import { join } from 'path';
import { init } from '../src/cli/commands/init.js';
import { createTask, claimTask, reviewTask } from '../src/core/services/taskService.js';
import { searchMemory } from '../src/core/services/memoryService.js';

describe('core correctness (TSK-0007)', () => {
  let cwd: string;

  beforeEach(() => {
    cwd = mkdtempSync(join(tmpdir(), 'ah-core-'));
    init(cwd, { projectName: 'core-test', yes: true });
  });

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

  // ── FTS5 duplicate-on-update ──────────────────────────────────────────────
  it('search returns no duplicates after an entity is updated repeatedly', () => {
    const t = createTask(cwd, { title: 'Zephyr indexing widget', role: 'implementer' });
    // Each mutation re-upserts into the FTS index.
    claimTask(cwd, t.id, 'kimi');
    reviewTask(cwd, t.id);

    const hits = searchMemory(cwd, 'Zephyr');
    const forTask = hits.filter((r) => r.id === t.id);
    expect(forTask).toHaveLength(1); // exactly one, not one-per-update
  });

  // ── claimTask race-guard ──────────────────────────────────────────────────
  it('only one of two concurrent claims on the same open task wins', () => {
    const t = createTask(cwd, { title: 'contended', role: 'implementer' });

    const winners: string[] = [];
    let refused = 0;
    for (const agent of ['kimi', 'codex']) {
      try {
        const claimed = claimTask(cwd, t.id, agent);
        winners.push(claimed.assignedTo ?? '');
      } catch {
        refused += 1;
      }
    }
    expect(winners).toHaveLength(1);
    expect(refused).toBe(1);
    expect(winners[0]).toBe('kimi'); // the first to act wins
  });

  it('a re-claim by the same agent is an idempotent no-op', () => {
    const t = createTask(cwd, { title: 'mine', role: 'implementer' });
    claimTask(cwd, t.id, 'kimi');
    const again = claimTask(cwd, t.id, 'kimi'); // no throw
    expect(again.status).toBe('in_progress');
    expect(again.claimedBy).toBe('kimi');
  });

  it('refuses to claim a task that is not open', () => {
    const t = createTask(cwd, { title: 'x', role: 'implementer' });
    claimTask(cwd, t.id, 'kimi');
    reviewTask(cwd, t.id); // now in review
    expect(() => claimTask(cwd, t.id, 'codex')).toThrow(/cannot be claimed/i);
  });
});