generate pdfs from images

app/javascript/elements/download_button.js

@@ -18,20 +18,27 @@ export default targetable(class extends HTMLElement {
     this.toggleState()
 
     fetch(this.dataset.src).then((response) => response.json()).then((urls) => {
-      urls.forEach((url) => {
-        fetch(url).then(async (resp) => {
-          const blobUrl = URL.createObjectURL(await resp.blob())
-          const link = document.createElement('a')
+      const fileRequests = urls.map((url) => {
+        return () => {
+          return fetch(url).then(async (resp) => {
+            const blobUrl = URL.createObjectURL(await resp.blob())
+            const link = document.createElement('a')
 
-          link.href = blobUrl
-          link.setAttribute('download', resp.headers.get('content-disposition').split('"')[1])
+            link.href = blobUrl
+            link.setAttribute('download', decodeURI(resp.headers.get('content-disposition').split('"')[1]))
 
-          link.click()
+            link.click()
 
-          URL.revokeObjectURL(url)
-        })
+            URL.revokeObjectURL(url)
+          })
+        }
       })
-    }).finally(() => {
+
+      fileRequests.reduce(
+        (prevPromise, request) => prevPromise.then(() => request()),
+        Promise.resolve()
+      )
+
       this.toggleState()
     })
   }