use file-type for mime and enhanced preview

and cleanup blob addition to text

package.json

@@ -26,6 +26,7 @@
     "@koa/router": "^8.0.0",
     "debug": "^4.1.1",
     "env-paths": "^2.2.0",
+    "file-type": "^15.0.1",
     "highlight.js": "^9.18.1",
     "hyperaxe": "^1.3.0",
     "is-svg": "^4.2.1",
@@ -41,6 +42,7 @@
     "pull-sort": "^1.0.2",
     "pull-stream": "^3.6.12",
     "require-style": "^1.1.0",
+    "sharp": "^0.25.2",
     "ssb-client": "^4.9.0",
     "ssb-config": "^3.4.4",
     "ssb-markdown": "^6.0.7",
@@ -49,8 +51,7 @@
     "ssb-ref": "^2.13.9",
     "ssb-tangle": "^1.0.1",
     "ssb-thread-schema": "^1.1.1",
-    "yargs": "^15.3.1",
-    "sharp": "^0.25.2"
+    "yargs": "^15.3.1"
   },
   "devDependencies": {
     "@types/debug": "^4.1.5",

src/index.js

@@ -663,7 +663,7 @@ router
     ctx.redirect(`/thread/${encodeURIComponent(message)}`);
   })
   .post("/publish/preview", koaBody({multipart: true }), async (ctx) => {
-    const text = String(ctx.request.body.text);
+    let text = String(ctx.request.body.text);
     const rawContentWarning = String(ctx.request.body.contentWarning).trim();
 
     const ssb = await cooler.open();
@@ -673,22 +673,22 @@ router
       image: await about.image(ssb.id),
     }
 
-    let blobId = false
+    let blob = false
     const blobUpload= ctx.request.files.blob
     if (typeof blobUpload !== "undefined") {
 
-      const blob = await fs.promises.readFile(blobUpload.path);
-      if (blob.length > 0) {
+      const data = await fs.promises.readFile(blobUpload.path);
+      if (data.length > 0) {
         // 5 MiB check
         const mebibyte = Math.pow(2, 20);
         const maxSize = 5 * mebibyte;
-        if (blob.length > maxSize) {
+        if (data.length > maxSize) {
           throw new Error("Blob file is too big, maximum size is 5 mebibytes");
         }
         
         const addBlob = new Promise((resolve, reject) => {
           pull(
-            pull.values([blob]),
+            pull.values([data]),
             ssb.blobs.add((err, hashedBlobRef) => {
               if (err) return reject(err);
               console.log("added", hashedBlobRef)
@@ -696,7 +696,30 @@ router
             })
           )
         })
-        blobId = await addBlob;
+        blob = {
+          id: await addBlob,
+          name: blobUpload.name
+        }
+        const FileType = require('file-type');
+        try {
+          let ftype = await FileType.fromBuffer(data)
+          blob.mime = ftype.mime
+        } catch (error) {
+          console.warn(error)
+          blob.mime = "application/octet-stream"
+        }
+      }
+    }
+    // append uploaded blob as markdown to the end of the input text
+    if (typeof blob !== "boolean") {
+      if (blob.mime.startsWith("image/")) {
+        text += `\n![${blob.name}](${blob.id})`
+      } else if (blob.mime.startsWith("audio/")) {
+        text += `\n![audio:${blob.name}](${blob.id})`
+      } else if (blob.mime.startsWith("video/")) {
+        text += `\n![video:${blob.name}](${blob.id})`
+      } else {
+        text += `\n[${blob.name}](${blob.id})`
       }
     }
         
@@ -704,7 +727,7 @@ router
     const contentWarning =
       rawContentWarning.length > 0 ? rawContentWarning : undefined;
 
-    ctx.body = await previewView({authorMeta, text, contentWarning, blobId});
+    ctx.body = await previewView({authorMeta, text, contentWarning});
   })
   .post("/publish/", koaBody(), async (ctx) => {
     const text = String(ctx.request.body.text);