const { test, before, after } = require('node:test');
const assert = require('node:assert/strict');
const fs = require('fs');
const os = require('os');
const path = require('path');
const { findExistingTrack } = require('../lib/metadata');

let ROOT;
const touch = (artist, album, file) => {
  const dir = path.join(ROOT, artist, album);
  fs.mkdirSync(dir, { recursive: true });
  fs.writeFileSync(path.join(dir, file), '');
};

before(() => {
  ROOT = fs.mkdtempSync(path.join(os.tmpdir(), 'ns-dedup-'));
  // KH single: normal "01 - " prefix, title contains multiple " - "
  touch('Geek Music', 'Kingdom Hearts 2 - Dearly Beloved - Main Theme - Single',
        '01 - Kingdom Hearts 2 - Dearly Beloved - Main Theme.mp3');
  // KH album variant: garbage "01-01" artist prefix, no track number
  touch('Geek Music', 'Kingdom Hearts 2 - Dearly Beloved - Main Theme',
        '01-01 - Kingdom Hearts 2 - Dearly Beloved - Main Theme.mp3');
  // Normal "Artist - Title" file
  touch('Some Artist', 'Therapy - Single', '01 - Some Artist - Therapy.mp3');
});
after(() => { try { fs.rmSync(ROOT, { recursive: true, force: true }); } catch {} });

test('detects a re-download when the title itself contains " - " (KH bug)', () => {
  assert.ok(findExistingTrack(ROOT, 'Geek Music', 'Kingdom Hearts 2 - Dearly Beloved - Main Theme'));
});

test('detects it even with a garbage "01-01 - " artist prefix', () => {
  // Both KH files should resolve; at least one must be found → dedup skips the re-download.
  const hit = findExistingTrack(ROOT, 'Geek Music', 'Kingdom Hearts 2 - Dearly Beloved - Main Theme');
  assert.ok(hit && hit.includes('Kingdom Hearts 2 - Dearly Beloved - Main Theme'));
});

test('normal "Artist - Title" filename still matches on title alone', () => {
  assert.ok(findExistingTrack(ROOT, 'Some Artist', 'Therapy'));
});

test('no false positive: a different title is not matched', () => {
  assert.equal(findExistingTrack(ROOT, 'Geek Music', 'Some Unrelated Song'), null);
  assert.equal(findExistingTrack(ROOT, 'Some Artist', 'Kingdom Hearts 2'), null);
});

test('remix stays distinct from the base track (no regression from the version-marker fix)', () => {
  assert.equal(findExistingTrack(ROOT, 'Some Artist', 'Therapy (Remix)'), null);
  assert.ok(findExistingTrack(ROOT, 'Some Artist', 'Therapy')); // base still found
});