[client-app] Ensure files get transferred in forwarded messages

Summary:
We need to download the files and then treat them as uploads. Rather
than using an actual Upload object, which would require another data
transfer, we create an object with all the necessary Upload-like
properties and point it to the downloaded file.

Addresses part of T7960

Test Plan: Manual, some specs

Reviewers: evan, spang, juan

Reviewed By: juan

Differential Revision: https://phab.nylas.com/D4249

packages/client-app/spec/stores/draft-factory-spec.es6

@@ -9,6 +9,7 @@ import {
   DraftStore,
   AccountStore,
   DatabaseStore,
+  FileDownloadStore,
   DatabaseTransaction,
   SanitizeTransformer,
   InlineStyleTransformer,
@@ -24,14 +25,30 @@ let fakeMessageWithFiles = null;
 let msgWithReplyToDuplicates = null;
 let msgWithReplyToFromMe = null;
 let account = null;
+const downloadData = {}
 
 describe('DraftFactory', function draftFactory() {
   beforeEach(() => {
     // Out of the scope of these specs
     spyOn(InlineStyleTransformer, 'run').andCallFake((input) => Promise.resolve(input));
     spyOn(SanitizeTransformer, 'run').andCallFake((input) => Promise.resolve(input));
+    spyOn(FileDownloadStore, 'downloadDataForFile').andCallFake((fid) => {
+      return downloadData[fid]
+    });
 
     account = AccountStore.accounts()[0];
+    const files = [
+      new File({filename: "test.jpg", accountId: account.id}),
+      new File({filename: "test.pdj", accountId: account.id}),
+    ];
+    files.forEach((file) => {
+      downloadData[file.id] = {
+        fileId: file.id,
+        filename: file.filename,
+        targetPath: file.filename,
+      }
+    })
+
 
     fakeThread = new Thread({
       id: 'fake-thread-id',
@@ -59,7 +76,7 @@ describe('DraftFactory', function draftFactory() {
       cc: [new Contact({email: 'mg@nylas.com'}), account.me()],
       bcc: [new Contact({email: 'recruiting@nylas.com'})],
       from: [new Contact({email: 'customer@example.com', name: 'Customer'})],
-      files: [new File({filename: "test.jpg"}), new File({filename: "test.pdj"})],
+      files: files,
       threadId: 'fake-thread-id',
       body: 'Fake Message 1',
       subject: 'Fake Subject',
@@ -368,11 +385,12 @@ describe('DraftFactory', function draftFactory() {
         expect(SanitizeTransformer.run).toHaveBeenCalled();
       });
 
-      it("should include the attached files", () => {
+      it("should include the attached files as uploads", () => {
         waitsForPromise(() => {
           return DraftFactory.createDraftForForward({thread: fakeThread, message: fakeMessageWithFiles}).then((draft) => {
-            expect(draft.files.length).toBe(2);
-            expect(draft.files[0].filename).toBe("test.jpg");
+            expect(draft.uploads.length).toBe(2);
+            expect(draft.uploads[0].filename).toBe("test.jpg");
+            expect(draft.uploads[1].filename).toBe("test.pdj");
           });
         });
       });

packages/client-app/src/flux/stores/draft-factory.coffee

@@ -1,4 +1,7 @@
 _ = require 'underscore'
+path = require 'path'
+
+{FileDownloadStore} = require 'nylas-exports'
 
 Actions = require('../actions').default
 DatabaseStore = require('./database-store').default
@@ -119,6 +122,9 @@ class DraftFactory
     )
 
   createDraftForForward: ({thread, message}) =>
+    # Start downloading the attachments, if they haven't been already
+    message.files.forEach((f) => Actions.fetchFile(f))
+
     contactsAsHtml = (cs) ->
       DOMUtils.escapeHTMLCharacters(_.invoke(cs, "toString").join(", "))
     fields = []
@@ -131,7 +137,6 @@ class DraftFactory
     DraftHelpers.prepareBodyForQuoting(message.body).then (body) =>
       @createDraft(
         subject: subjectWithPrefix(message.subject, 'Fwd:')
-        files: [].concat(message.files),
         from: [@_fromContactForReply(message)],
         threadId: thread.id,
         accountId: message.accountId,
@@ -145,7 +150,21 @@ class DraftFactory
             <br><br>
             #{body}
           </div>"""
-      )
+      ).then (draft) =>
+        draft.uploads = message.files.map((f) =>
+          {fileId, filename, filesize, targetPath} = FileDownloadStore.downloadDataForFile(f.id)
+          # Return an object that can act as an Upload instance.
+          return (
+            messageClientId: draft.clientId,
+            id: fileId,
+            filename: filename,
+            size: filesize,
+            targetPath: targetPath,
+            targetDir: path.dirname(targetPath)
+          )
+        )
+        return draft
+
 
   candidateDraftForUpdating: (message, behavior) =>
     if behavior not in ['prefer-existing-if-pristine', 'prefer-existing']