Handle case where webm has no metadata that can be leeched off

src/main.ts

@@ -155,7 +155,6 @@ const processPost = async (post: HTMLDivElement) => {
 };
 
 const startup = async () => {
-    await Promise.all([...document.querySelectorAll('.postContainer')].map(e => processPost(e as any)));
 
     //await Promise.all([...document.querySelectorAll('.postContainer')].filter(e => e.textContent?.includes("191 KB")).map(e => processPost(e as any)));
 
@@ -173,6 +172,7 @@ const startup = async () => {
     };
 
     let injected = false;
+    debugger;
     document.addEventListener('QRDialogCreation', <any>((e: CustomEvent<string>) => {
         if (injected)
             return;
@@ -196,14 +196,18 @@ const startup = async () => {
                     const proc = processors.find(e => file.name.match(e[0]));
                     if (!proc)
                         return;
+                    const buff = await proc[2](file, input.files[0]);
                     document.dispatchEvent(new CustomEvent('QRSetFile', {
-                        detail: await proc[2](file, input.files[0])
+                        detail: { file: new Blob([buff]), name: input.files[0].name }
                     }));
                 }
             });
             input.click();
         };
     }));
+
+    await Promise.all([...document.querySelectorAll('.postContainer')].map(e => processPost(e as any)));
+
 };
 
 document.addEventListener('4chanXInitFinished', startup);

src/webm.ts

@@ -33,14 +33,52 @@ const printChunks = (chunks: ebml.EBMLElementDetail[], ptr = 0, depth = 0): void
     }
 };
 
+const findEnclosingTag = (ch: ebml.EBMLElementDetail[], name: string): [number, number] | undefined => {
+    const first = ch.findIndex(e => e.type == 'm' && e.name == name);
+    if (first < 0)
+        return;
+    const second = ch.slice(first).findIndex(e => e.type == 'm' && e.name == name);
+    if (second < 0)
+        return;
+    return [
+        first, first + second
+    ];
+};
+
 const embed = (webm: Buffer, data: Buffer) => {
     const dec = new ebml.Decoder();
     const chunks = dec.decode(webm);
     const enc = new ebml.Encoder();
-    const embed = chunks.findIndex(e => e.name == "Targets" && e.type == "m" && e.isEnd);
-    if (embed == -1)
-        throw "Cannot embed, no tags section...";
-    // That's basically budget binary XML
+
+    let embed = chunks.findIndex(e => e.name == "Tracks" && e.type == "m" && e.isEnd);
+
+    const findOrInsert = (n: string) => {
+        let tags = findEnclosingTag(chunks, n);
+        const stack = [];
+        if (!tags) {
+            stack.push({
+                type: "m",
+                isEnd: false,
+                name: n,
+                data: Buffer.from('')
+            });
+            stack.push({
+                type: "m",
+                isEnd: true,
+                name: n,
+                data: Buffer.from('')
+            });
+            chunks.splice(embed + 1, 0, ...stack as any);
+            tags = findEnclosingTag(chunks, n);
+        }
+        embed = tags![1];    
+    };
+    
+    findOrInsert('Tags');
+    findOrInsert('Tag');
+    findOrInsert('Targets');
+    embed++;
+
     chunks.splice(embed + 1, 0, ...[
         {
             type: "m",