feat: proxy HLS manifest encryption key URIs and refine segment URL proxying

lib/utils/proxy-utils.ts

@@ -8,15 +8,32 @@ export async function processM3u8Content(
     const base = new URL(baseUrl);
 
     const processedLines = lines.map(line => {
-        // Skip comments and empty lines
-        if (line.trim().startsWith('#') || !line.trim()) {
+        const trimmed = line.trim();
+
+        // Handle EXT-X-KEY encryption keys
+        if (trimmed.startsWith('#EXT-X-KEY:')) {
+            // Extract URI from the key tag
+            const uriMatch = trimmed.match(/URI="([^"]+)"/);
+            if (uriMatch && uriMatch[1]) {
+                const keyUri = uriMatch[1];
+                try {
+                    const absoluteUrl = new URL(keyUri, base).toString();
+                    const proxiedUrl = `${origin}/api/proxy?url=${encodeURIComponent(absoluteUrl)}`;
+                    return trimmed.replace(/URI="[^"]+"/, `URI="${proxiedUrl}"`);
+                } catch {
+                    return line;
+                }
+            }
+        }
+
+        // Skip other comments and empty lines
+        if (trimmed.startsWith('#') || !trimmed) {
             return line;
         }
 
-        // Resolve relative URLs
+        // Resolve relative URLs for segments
         try {
-            const absoluteUrl = new URL(line.trim(), base).toString();
-            // Wrap in proxy
+            const absoluteUrl = new URL(trimmed, base).toString();
             return `${origin}/api/proxy?url=${encodeURIComponent(absoluteUrl)}`;
         } catch {
             return line;