feat: Enhance M3U8 ad detection with proxy URL unwrapping and segment-level analysis, and implement proxy fallback for HLS playlist fetching.

lib/utils/m3u8-ad-detector.ts

@@ -103,12 +103,30 @@ export function parseBlocks(lines: string[]): Block[] {
     return blocks;
 }
 
+/**
+ * Unwrap proxied URL to get original URL
+ */
+function unwrapProxyUrl(url: string): string {
+    if (url.includes('/api/proxy?url=')) {
+        try {
+            const match = url.match(/[?&]url=([^&]+)/);
+            if (match && match[1]) {
+                return decodeURIComponent(match[1]);
+            }
+        } catch {
+            return url;
+        }
+    }
+    return url;
+}
+
 /**
  * Extract filename from URL (handles both relative and absolute URLs)
  */
 function extractFilename(url: string): string {
     try {
-        const path = url.includes('://') ? new URL(url).pathname : url;
+        const unwrappedUrl = unwrapProxyUrl(url);
+        const path = unwrappedUrl.includes('://') ? new URL(unwrappedUrl).pathname : unwrappedUrl;
         const parts = path.split('/');
         return parts[parts.length - 1] || '';
     } catch {
@@ -143,7 +161,8 @@ function findCommonPrefix(strings: string[]): string {
  */
 function extractPathPrefix(url: string): string {
     try {
-        const path = url.includes('://') ? new URL(url).pathname : url;
+        const unwrappedUrl = unwrapProxyUrl(url);
+        const path = unwrappedUrl.includes('://') ? new URL(unwrappedUrl).pathname : unwrappedUrl;
         const lastSlash = path.lastIndexOf('/');
         return lastSlash >= 0 ? path.substring(0, lastSlash + 1) : '';
     } catch {
@@ -234,7 +253,7 @@ export function scoreBlock(block: Block, mainPattern: MainPattern, extraKeywords
 
     // **KEY FEATURE**: Check path prefix mismatch (e.g., different date/folder/bitrate)
     // This is the most reliable indicator for ads that come from different CDN paths
-    if (mainPattern.pathPrefix && block.segments.length > 0) {
+    if (mainPattern.pathPrefix !== undefined && block.segments.length > 0) {
         const pathMismatchCount = block.segments.filter(s => {
             const segmentPathPrefix = extractPathPrefix(s.url);
             return segmentPathPrefix !== mainPattern.pathPrefix;

lib/utils/m3u8-utils.ts

@@ -25,10 +25,21 @@ export function filterM3u8Ad(content: string, baseUrl: string, mode: AdFilterMod
     // Use keywords passed from AdKeywordsWrapper (already loaded from env/file)
     const keywords = customKeywords;
 
-    const basePath = baseUrl.substring(0, baseUrl.lastIndexOf('/') + 1);
+    // Unwrap baseUrl if it's a proxy URL to get correct basePath and origin
+    let effectiveBaseUrl = baseUrl;
+    if (baseUrl.includes('/api/proxy?url=')) {
+        try {
+            const urlMatch = baseUrl.match(/[?&]url=([^&]+)/);
+            if (urlMatch && urlMatch[1]) {
+                effectiveBaseUrl = decodeURIComponent(urlMatch[1]);
+            }
+        } catch (e) { /* ignore */ }
+    }
+
+    const basePath = effectiveBaseUrl.substring(0, effectiveBaseUrl.lastIndexOf('/') + 1);
     let origin = '';
     try {
-        origin = new URL(baseUrl).origin;
+        origin = new URL(effectiveBaseUrl).origin;
     } catch (e) { /* ignore */ }
 
     // 2. Global Scan: Check if any ad keywords exist in the content
@@ -42,18 +53,37 @@ export function filterM3u8Ad(content: string, baseUrl: string, mode: AdFilterMod
     if (!hasCueTag && (mode === 'heuristic' || mode === 'aggressive')) {
         // No obvious ad signals - run heuristic analysis
         const blocks = parseBlocks(lines);
-        if (blocks.length > 1) {
+        if (blocks.length > 0) {
             const mainPattern = learnMainPattern(blocks);
             for (const block of blocks) {
                 // Pass all keywords (including custom ones) to heuristic scorer
                 const score = scoreBlock(block, mainPattern, keywords);
                 const threshold = mode === 'aggressive' ? 3.0 : 5.0;
+
                 if (shouldFilterBlock(score, threshold)) {
                     // Mark all lines in this block for removal
                     for (const segment of block.segments) {
                         adLineIndices.add(segment.lineIndex);
                         adLineIndices.add(segment.lineIndex - 1); // EXTINF line
                     }
+                } else if (block.segments.length > 0) {
+                    // Segment-level detection: 
+                    // Even if the whole block didn't trigger, check segments individually 
+                    // if it's a suspicious single-segment "block" (common for ads without discontinuity)
+                    for (const segment of block.segments) {
+                        const singleSegmentBlock = {
+                            segments: [segment],
+                            hasCueTag: false,
+                            startLineIndex: segment.lineIndex - 1,
+                            endLineIndex: segment.lineIndex
+                        };
+                        const segmentScore = scoreBlock(singleSegmentBlock, mainPattern, keywords);
+                        // Higher threshold for individual segments to avoid false positives
+                        if (segmentScore >= 4.0) {
+                            adLineIndices.add(segment.lineIndex);
+                            adLineIndices.add(segment.lineIndex - 1);
+                        }
+                    }
                 }
             }
         }