const test = require('node:test');
const assert = require('node:assert/strict');
const { parsePlatforms, discoverPlatforms, toArchTag } = require('../lib/platforms.js');

test('parsePlatforms handles empty and undefined input', () => {
  assert.deepEqual(parsePlatforms(''), []);
  assert.deepEqual(parsePlatforms(null), []);
  assert.deepEqual(parsePlatforms(undefined), []);
  assert.deepEqual(parsePlatforms('   '), []);
});

test('parsePlatforms parses comma-separated architectures and adds linux/ prefix if omitted', () => {
  const result = parsePlatforms('amd64, arm64, linux/arm/v7');
  assert.deepEqual(result, ['linux/amd64', 'linux/arm64', 'linux/arm/v7']);
});

test('discoverPlatforms extracts unique architectures from OCI image manifests', () => {
  const headManifest = JSON.stringify({
    manifests: [
      { platform: { architecture: 'amd64', os: 'linux' } },
      { platform: { architecture: 'arm64', os: 'linux' } },
      { platform: { architecture: 'unknown', os: 'unknown' } },
    ],
  });

  const targetManifest = JSON.stringify({
    manifests: [
      { platform: { architecture: 'amd64', os: 'linux' } },
      { platform: { architecture: 'arm', os: 'linux', variant: 'v7' } },
    ],
  });

  const result = discoverPlatforms(headManifest, targetManifest);
  assert.deepEqual(result, ['linux/amd64', 'linux/arm/v7', 'linux/arm64']);
});

test('discoverPlatforms safely handles invalid or missing manifest JSON', () => {
  assert.deepEqual(discoverPlatforms('invalid json', null), []);
  assert.deepEqual(discoverPlatforms('', '{}'), []);
});

test('toArchTag converts platform strings to filesystem-safe arch tags', () => {
  assert.equal(toArchTag('linux/amd64'), 'amd64');
  assert.equal(toArchTag('linux/arm64'), 'arm64');
  assert.equal(toArchTag('linux/arm/v7'), 'arm-v7');
  assert.equal(toArchTag('amd64'), 'amd64');
});