import { describe, it, expect, beforeAll } from 'vitest';
import { pool } from '../../lib/db/pool.js';
import { resetDb } from '../helpers/db.js';
import { migrateUp } from '../../lib/db/migrate.js';
import { listMcpTools, callMcpTool } from '../../lib/mcp/companion-stdio.js';

let spaceId, agentId;

beforeAll(async () => {
  await resetDb();
  await migrateUp();
  ({ rows: [{ id: spaceId }] } = await pool.query(
    `INSERT INTO spaces(slug,name) VALUES('mcp-test','MCP Test') RETURNING id`
  ));
  ({ rows: [{ id: agentId }] } = await pool.query(
    `SELECT id FROM agents WHERE slug='companion'`
  ));
});

const suggestAgent = (id) => ({
  kind: 'agent',
  id,
  capabilities: { read: true, suggest: true, write: false },
  scopes: {}
});

describe('listMcpTools()', () => {
  it('returns exactly the five companion tools sorted by name', () => {
    const tools = listMcpTools();
    expect(tools.map(t => t.name).sort()).toEqual(['context', 'propose_change', 'propose_improvement', 'read', 'search']);
  });

  it('each tool has name, description, and input_schema', () => {
    const tools = listMcpTools();
    for (const t of tools) {
      expect(t.name).toBeTruthy();
      expect(t.description).toBeTruthy();
      expect(t.input_schema).toBeTruthy();
      expect(t.input_schema.type).toBe('object');
    }
  });
});

describe('callMcpTool()', () => {
  it('propose_change writes a pending_changes row (pending) and returns applied:false', async () => {
    const ctx = { agent: suggestAgent(agentId), space_id: spaceId };
    const result = await callMcpTool(
      'propose_change',
      {
        entity_type: 'task',
        action: 'create',
        payload: { space_id: spaceId, title: 'MCP test task' }
      },
      ctx
    );

    expect(result.pending_change_id).toBeTruthy();
    expect(result.applied).toBe(false);

    // Check DB: the row exists and is pending
    const { rows } = await pool.query(
      `SELECT * FROM pending_changes WHERE id=$1`,
      [result.pending_change_id]
    );
    expect(rows).toHaveLength(1);
    expect(rows[0].status).toBe('pending');
    expect(rows[0].agent_id).toBe(agentId);

    // The task was NOT created
    const { rows: tasks } = await pool.query(
      `SELECT * FROM tasks WHERE title='MCP test task'`
    );
    expect(tasks).toHaveLength(0);
  });
});