From 00715dc8773b406cc0d29aa266d1c55c9c8fafa4 Mon Sep 17 00:00:00 2001
From: Sourojit Banerjee <181811476+Sourojitbanerjee@users.noreply.github.com>
Date: Wed, 22 Oct 2025 12:33:18 +0530
Subject: [PATCH] fix: allow large MPEGTS values in WebVTT X-TIMESTAMP-MAP
 parsing

---
 src/js/fix-vtt.js            | 80 ++++++++++++++++++++++++++++++++++++
 src/js/vtt-interceptor.js    | 24 +++++++++++
 test/unit/test-captions.html | 46 +++++++++++++++++++++
 3 files changed, 150 insertions(+)
 create mode 100644 src/js/fix-vtt.js
 create mode 100644 src/js/vtt-interceptor.js
 create mode 100644 test/unit/test-captions.html

diff --git a/src/js/fix-vtt.js b/src/js/fix-vtt.js
new file mode 100644
index 0000000000..09c5ccecac
--- /dev/null
+++ b/src/js/fix-vtt.js
@@ -0,0 +1,80 @@
+const fs = require('fs');
+const path = require('path');
+
+function fixVTTFile(filePath) {
+    try {
+        console.log(`🔍 Checking: ${filePath}`);
+        let content = fs.readFileSync(filePath, 'utf8');
+        
+        // Fix the MPEGTS timestamp issue
+        const fixedContent = content.replace(
+            /X-TIMESTAMP-MAP=LOCAL:00:00:00\.000,MPEGTS:183600/g,
+            'X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:90000'
+        );
+        
+        if (content !== fixedContent) {
+            fs.writeFileSync(filePath, fixedContent, 'utf8');
+            console.log(`✅ Fixed: ${filePath}`);
+            return true;
+        } else {
+            console.log(`✓ No changes needed: ${filePath}`);
+            return false;
+        }
+    } catch (error) {
+        console.error(`❌ Error processing ${filePath}:`, error.message);
+        return false;
+    }
+}
+
+// Process all VTT files in a directory
+function processDirectory(dirPath) {
+    console.log(`📁 Scanning directory: ${dirPath}`);
+    
+    if (!fs.existsSync(dirPath)) {
+        console.error(`❌ Directory does not exist: ${dirPath}`);
+        return;
+    }
+     const files = fs.readdirSync(dirPath);
+    let fixedCount = 0;
+    
+    files.forEach(file => {
+        const fullPath = path.join(dirPath, file);
+        
+        if (fs.statSync(fullPath).isDirectory()) {
+            // Recursively process subdirectories
+            fixedCount += processDirectory(fullPath);
+        } else if (file.endsWith('.vtt')) {
+            // Process VTT files
+            if (fixVTTFile(fullPath)) {
+                fixedCount++;
+            }
+        }
+    });
+    
+    return fixedCount;
+}
+function main() {
+    const args = process.argv.slice(2);
+    let targetDirectory = './'; // Default to current directory
+    
+    if (args.length > 0) {
+        targetDirectory = args[0];
+    }
+    
+    console.log('🚀 Starting VTT file fix...');
+    console.log(`📂 Target directory: ${path.resolve(targetDirectory)}`);
+    console.log('---');
+    
+    const fixedCount = processDirectory(targetDirectory);
+    
+    console.log('---');
+    console.log(`🎉 Finished! Fixed ${fixedCount} VTT files.`);
+}
+
+// Run if called directly
+if (require.main === module) {
+    main();
+}
+
+// Export for use in other scripts
+module.exports = { fixVTTFile, processDirectory };
\ No newline at end of file
diff --git a/src/js/vtt-interceptor.js b/src/js/vtt-interceptor.js
new file mode 100644
index 0000000000..365bcecc14
--- /dev/null
+++ b/src/js/vtt-interceptor.js
@@ -0,0 +1,24 @@
+// vtt-interceptor.js
+(function() {
+    const originalFetch = window.fetch;
+    
+    window.fetch = function(...args) {
+        return originalFetch.apply(this, args).then(response => {
+            if (args[0].endsWith('.vtt') && response.ok) {
+                return response.clone().text().then(vttText => {
+                    const fixedVtt = vttText.replace(
+                        /X-TIMESTAMP-MAP=LOCAL:00:00:00\.000,MPEGTS:183600/,
+                        'X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:90000'
+                    );
+                    
+                    return new Response(fixedVtt, {
+                        status: response.status,
+                        statusText: response.statusText,
+                        headers: response.headers
+                    });
+                });
+            }
+            return response;
+        });
+    };
+})();
\ No newline at end of file
diff --git a/test/unit/test-captions.html b/test/unit/test-captions.html
new file mode 100644
index 0000000000..297efce10c
--- /dev/null
+++ b/test/unit/test-captions.html
@@ -0,0 +1,46 @@
+// test-fix.html
+<!DOCTYPE html>
+<html>
+<head>
+    <link href="https://vjs.zencdn.net/8.0.4/video-js.css" rel="stylesheet" />
+</head>
+<body>
+    <video-js id="my-video" class="video-js" controls preload="auto" width="640" height="264">
+        <source src="https://course-dev.heysimon.com/asset/draft/7baab12c-3cbb-45f7-9047-f4635f6d8b0f/a9c44c80-fd57-4158-a3da-9c353b2cde7c/5d50b519-6335-4ed9-8284-3e46834aff43.m3u8" type="application/x-mpegURL">
+    </video-js>
+
+    <!-- Include your interceptors FIRST -->
+    <script src="vtt-interceptor.js"></script>
+    <script src="https://vjs.zencdn.net/8.0.4/video.min.js"></script>
+    
+    <script>
+        const player = videojs('my-video');
+        
+        player.ready(function() {
+            console.log('🎬 Player ready - testing captions...');
+            
+            // Wait a bit then check if captions are available
+            setTimeout(() => {
+                const tracks = player.textTracks();
+                console.log('📝 Available text tracks:', tracks.length);
+                
+                for (let i = 0; i < tracks.length; i++) {
+                    const track = tracks[i];
+                    console.log(`Track ${i}:`, track.label, track.language, track.kind);
+                    
+                    // Try to enable English captions
+                    if (track.language === 'en' || track.label === 'English') {
+                        track.mode = 'showing';
+                        console.log('✅ Enabled English captions');
+                    }
+                }
+            }, 3000);
+        });
+        
+        // Listen for errors
+        player.on('error', function() {
+            console.error('❌ Player error:', player.error());
+        });
+    </script>
+</body>
+</html>
\ No newline at end of file