feat: add configurable HLS CORS allowlists

tests/Cors/CorsPolicyTest.php

@@ -0,0 +1,54 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Plugin\AzuraCastOnDemandHls\Tests\Cors;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+use Plugin\AzuraCastOnDemandHls\Cors\CorsPolicy;
+
+#[CoversClass(CorsPolicy::class)]
+final class CorsPolicyTest extends TestCase
+{
+    private CorsPolicy $policy;
+
+    protected function setUp(): void
+    {
+        $this->policy = new CorsPolicy(['https://aifrequency.org', 'https://www.aifrequency.org']);
+    }
+
+    public function testItAllowsTheFirstExplicitOrigin(): void
+    {
+        self::assertSame([
+            'Access-Control-Allow-Origin' => 'https://aifrequency.org',
+            'Vary' => 'Origin',
+        ], $this->policy->headersFor('https://aifrequency.org'));
+    }
+
+    public function testItAllowsTheSecondExplicitOrigin(): void
+    {
+        self::assertSame('https://www.aifrequency.org', $this->policy->headersFor('https://www.aifrequency.org')['Access-Control-Allow-Origin']);
+    }
+
+    public function testItDoesNotAllowAnUnapprovedOrigin(): void
+    {
+        self::assertSame(['Vary' => 'Origin'], $this->policy->headersFor('https://evil.example'));
+    }
+
+    public function testItDoesNotAddCorsHeadersWithoutAnOrigin(): void
+    {
+        self::assertSame([], $this->policy->headersFor(null));
+    }
+
+    public function testItBuildsAConstrainedHlsPreflightResponse(): void
+    {
+        self::assertSame([
+            'Access-Control-Allow-Origin' => 'https://aifrequency.org',
+            'Vary' => 'Origin',
+            'Access-Control-Allow-Methods' => 'GET, HEAD, OPTIONS',
+            'Access-Control-Allow-Headers' => 'Range',
+            'Access-Control-Max-Age' => '600',
+        ], $this->policy->headersFor('https://aifrequency.org', true));
+    }
+}