// FTS keyword search — tests the REAL buildFtsQuery against a real FTS5 table.
// Uses Node's built-in node:sqlite (no external deps) to build a throwaway index,
// so this runs offline with nothing installed beyond Node itself.
const { test, before } = require('node:test');
const assert = require('node:assert');
const { buildFtsQuery } = require('../packages/memory-service/src/episodic/index');

let DatabaseSync;
try {
  ({ DatabaseSync } = require('node:sqlite'));
} catch {
  DatabaseSync = null;
}

const ROWS = [
  'To configure the Qdrant collection you set the vector size and distance metric',
  'The embedding service wraps nomic-embed-text via Ollama',
  'Reciprocal rank fusion merges semantic and keyword results',
  'I had a great morning walk today',
];

let db;
before(() => {
  if (!DatabaseSync) return;
  db = new DatabaseSync(':memory:');
  db.exec('CREATE VIRTUAL TABLE fts USING fts5(body)');
  const ins = db.prepare('INSERT INTO fts(rowid, body) VALUES (?, ?)');
  ROWS.forEach((r, i) => ins.run(i + 1, r));
});

const matchRows = (match) =>
  db.prepare('SELECT rowid FROM fts WHERE fts MATCH ? ORDER BY rank').all(match).map(r => r.rowid);

// --- Pure buildFtsQuery behaviour (runs without sqlite) ---

test('tokenizes and OR-joins significant terms, dropping stopwords', () => {
  assert.strictEqual(
    buildFtsQuery('How do I configure the Qdrant collection?'),
    '"configure" OR "qdrant" OR "collection"',
  );
});

test('all-stopword / empty input returns null so caller can skip keyword search', () => {
  assert.strictEqual(buildFtsQuery('how do I do it?'), null);
  assert.strictEqual(buildFtsQuery('   '), null);
  assert.strictEqual(buildFtsQuery('!!! ??? ...'), null);
});

test('FTS-significant tokens in the message are neutralized as literals', () => {
  // "OR" and the stray quote/asterisk must not become operators
  const q = buildFtsQuery('fusion OR results" hack*');
  assert.strictEqual(q, '"fusion" OR "results" OR "hack"');
});

// --- Real FTS5 matching (skips cleanly if node:sqlite is unavailable) ---

test('a conversational query matches on shared terms (the whole point of the fix)', { skip: !DatabaseSync }, () => {
  const q = buildFtsQuery('How do I configure the Qdrant collection?');
  assert.deepStrictEqual(matchRows(q), [1], 'should hit the Qdrant-collection episode');
});

test('the OLD whole-phrase approach would NOT have matched (regression guard)', { skip: !DatabaseSync }, () => {
  const oldPhrase = `"${'How do I configure the Qdrant collection?'.replace(/"/g, '""')}"`;
  assert.deepStrictEqual(matchRows(oldPhrase), [], 'verbatim phrase never appears → the bug we fixed');
});

test('injection-y input runs without error and matches real terms', { skip: !DatabaseSync }, () => {
  const q = buildFtsQuery('fusion OR results" hack*');
  assert.deepStrictEqual(matchRows(q), [3]);
});