'use strict';

const test = require('node:test');
const assert = require('node:assert/strict');
const path = require('node:path');
const { loadAtlasDirs } = require('../src/atlas-loader');

const FIX = path.join(__dirname, 'fixtures', 'atlases');
const FIX_DUP = path.join(__dirname, 'fixtures', 'atlases-dup');

test('loadAtlasDirs: discovers two atlases in one dir', () => {
  const { registry, warnings } = loadAtlasDirs([FIX]);
  assert.equal(warnings.length, 0);
  assert.deepEqual(Object.keys(registry).sort(), ['atlas_a', 'atlas_b']);
});

test('loadAtlasDirs: builds tilesByName and tilesById maps', () => {
  const { registry } = loadAtlasDirs([FIX]);
  const a = registry['atlas_a'];
  assert.equal(a.tilesByName['grass'], 1);
  assert.equal(a.tilesByName['stone'], 2);
  assert.equal(a.tilesById[1], 'grass');
  assert.equal(a.tilesById[2], 'stone');
  assert.ok(a.specPath.endsWith('tiles.atlas.json'));
});

test('loadAtlasDirs: empty input → empty registry, no warnings', () => {
  const { registry, warnings } = loadAtlasDirs([]);
  assert.deepEqual(registry, {});
  assert.deepEqual(warnings, []);
});

test('loadAtlasDirs: duplicate atlas_id → first wins, warning emitted', () => {
  const { registry, warnings } = loadAtlasDirs([FIX, FIX_DUP]);
  // First dir wins: atlas_a has 'grass' name, not 'ALT_grass'
  assert.equal(registry['atlas_a'].tilesByName['grass'], 1);
  assert.equal(registry['atlas_a'].tilesByName['ALT_grass'], undefined);
  assert.equal(warnings.length, 1);
  assert.match(warnings[0], /atlas_a/);
  assert.match(warnings[0], /duplicate/i);
});

test('loadAtlasDirs: reverse path order swaps the winner', () => {
  const { registry, warnings } = loadAtlasDirs([FIX_DUP, FIX]);
  assert.equal(registry['atlas_a'].tilesByName['ALT_grass'], 1);
  assert.equal(registry['atlas_a'].tilesByName['grass'], undefined);
  assert.equal(warnings.length, 1);
});

test('loadAtlasDirs: missing directory throws', () => {
  assert.throws(
    () => loadAtlasDirs(['/no/such/path/exists']),
    /no such directory/i
  );
});

test('loadAtlasDirs: dir with no tiles.atlas.json subdirs → empty registry', () => {
  // Use sporel-tool-mapper/src/ which has no atlas specs
  const noAtlasDir = path.join(__dirname, '..', 'src');
  const { registry, warnings } = loadAtlasDirs([noAtlasDir]);
  assert.deepEqual(registry, {});
  assert.equal(warnings.length, 0);
});