MOBILE-4482 forum: Avoid reuploading files when editing post

Author: dpalou

src/addons/mod/forum/components/post/post.ts

@@ -39,7 +39,7 @@ import {
 } from '../../services/forum';
 import { CoreTag } from '@features/tag/services/tag';
 import { Translate } from '@singletons';
-import { CoreFileUploader } from '@features/fileuploader/services/fileuploader';
+import { CoreFileUploader, CoreFileUploaderStoreFilesResult } from '@features/fileuploader/services/fileuploader';
 import { AddonModForumSync } from '../../services/forum-sync';
 import { CoreSync } from '@services/sync';
 import { CoreText } from '@singletons/text';
@@ -57,6 +57,7 @@ import { CoreToasts } from '@services/toasts';
 import { toBoolean } from '@/core/transforms/boolean';
 import { CorePopovers } from '@services/popovers';
 import { CoreLoadings } from '@services/loadings';
+import { CoreWSFile } from '@services/ws';
 
 /**
  * Components that shows a discussion post, its attachments and the action buttons allowed (reply, etc.).
@@ -214,7 +215,7 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
         this.formData.isEditing = !!isEditing;
         this.formData.subject = subject || this.defaultReplySubject || '';
         this.formData.message = message || null;
-        this.formData.files = files || [];
+        this.formData.files = (files ?? []).slice(); // Make a copy to avoid modifying the original array.
         this.formData.isprivatereply = !!isPrivate;
         this.formData.id = postId;
 
@@ -392,10 +393,9 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
             return;
         }
 
-        let saveOffline = false;
         let message = this.formData.message;
         const subject = this.formData.subject;
-        const replyingTo = this.formData.replyingTo!;
+        const replyingTo = this.formData.replyingTo ?? 0;
         const files = this.formData.files || [];
         const isEditOnline = this.formData.id && this.formData.id > 0;
         const modal = await CoreLoadings.show('core.sending', true);
@@ -413,73 +413,56 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
         // Add some HTML to the message if needed.
         message = CoreText.formatHtmlLines(message);
 
-        // Upload attachments first if any.
-        let attachments;
-
         try {
-            if (files.length) {
-                try {
-                    attachments = await AddonModForumHelper.uploadOrStoreReplyFiles(
-                        this.forum.id,
-                        isEditOnline ? this.formData.id! : replyingTo,
-                        files,
-                        false,
-                    );
-                } catch (error) {
-                    // Cannot upload them in online, save them in offline.
-                    if (!this.forum.id || isEditOnline || CoreUtils.isWebServiceError(error)) {
-                        // Cannot store them in offline. Reject.
-                        throw error;
-                    }
-
-                    saveOffline = true;
-                    attachments = await AddonModForumHelper.uploadOrStoreReplyFiles(this.forum.id, replyingTo, files, true);
-                }
-            }
-
             let sent = false;
 
-            if (isEditOnline) {
-                sent = await AddonModForum.updatePost(this.formData.id!, subject, message, {
+            if (this.formData.id && this.formData.id > 0) {
+                const attachments = await this.uploadAttachmentsForEditOnline(this.formData.id);
+
+                sent = await AddonModForum.updatePost(this.formData.id, subject, message, {
                     attachmentsid: attachments,
                     inlineattachmentsid: this.preparePostData?.draftitemid,
                 });
-            } else if (saveOffline) {
-                // Save post in offline.
-                await AddonModForumOffline.replyPost(
-                    replyingTo,
-                    this.discussionId,
-                    this.forum.id,
-                    this.forum.name,
-                    this.courseId,
-                    subject,
-                    message,
-                    {
-                        attachmentsid: attachments,
-                        private: !!this.formData.isprivatereply,
-                    },
-                );
-
-                // Set sent to false since it wasn't sent to server.
-                sent = false;
             } else {
-                // Try to send it to server.
-                // Don't allow offline if there are attachments since they were uploaded fine.
-                sent = await AddonModForum.replyPost(
-                    replyingTo,
-                    this.discussionId,
-                    this.forum.id,
-                    this.forum.name,
-                    this.courseId,
-                    subject,
-                    message,
-                    {
-                        attachmentsid: attachments,
-                        private: !!this.formData.isprivatereply,
-                    },
-                    undefined,
-                    !files.length,
-                );
+                const { attachments, saveOffline } = await this.uploadAttachmentsForReply(replyingTo);
+
+                if (saveOffline) {
+                    // Save post in offline.
+                    await AddonModForumOffline.replyPost(
+                        replyingTo,
+                        this.discussionId,
+                        this.forum.id,
+                        this.forum.name,
+                        this.courseId,
+                        subject,
+                        message,
+                        {
+                            attachmentsid: attachments,
+                            private: !!this.formData.isprivatereply,
+                        },
+                    );
+
+                    // Set sent to false since it wasn't sent to server.
+                    sent = false;
+                } else {
+                    // Try to send it to server.
+                    // Don't allow offline if there are attachments since they were uploaded fine.
+                    sent = await AddonModForum.replyPost(
+                        replyingTo,
+                        this.discussionId,
+                        this.forum.id,
+                        this.forum.name,
+                        this.courseId,
+                        subject,
+                        message,
+                        {
+                            attachmentsid: attachments,
+                            private: !!this.formData.isprivatereply,
+                        },
+                        undefined,
+                        !files.length,
+                    );
+                }
             }
 
             if (sent && this.forum.id) {
@@ -506,6 +489,81 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
         }
     }
 
+    /**
+     * Upload attachments when editing an online post.
+     *
+     * @param postId Post ID being edited.
+     * @returns Draft area id (if any attachment has changed).
+     */
+    protected async uploadAttachmentsForEditOnline(postId: number): Promise<number | undefined> {
+        const files = this.formData.files || [];
+        const previousAttachments = (this.post.attachments ?? []) as CoreWSFile[];
+
+        if (!CoreFileUploader.areFileListDifferent(files, previousAttachments)) {
+            return;
+        }
+
+        // Use prepare post for edition to avoid re-uploading all files.
+        let filesToKeep = files.filter((file): file is CoreWSFile => !CoreUtils.isFileEntry(file));
+        let removedFiles: { filepath: string; filename: string }[] | undefined;
+
+        if (previousAttachments.length && !filesToKeep.length) {
+            // Post had attachments but they were all removed. We cannot use the filesToKeep option because it doesn't allow
+            // removing all files. In this case we'll just keep 1 file and remove it later.
+            filesToKeep = [previousAttachments[0]];
+            removedFiles = [{
+                filename: previousAttachments[0].filename ?? '',
+                filepath: previousAttachments[0].filepath ?? '',
+            }];
+        }
+
+        const preparePostData = await AddonModForum.preparePostForEdition(postId, 'attachment', { filesToKeep });
+
+        if (removedFiles?.length) {
+            await CoreFileUploader.deleteDraftFiles(preparePostData.draftitemid, removedFiles);
+        }
+
+        await CoreFileUploader.uploadFiles(preparePostData.draftitemid, files);
+
+        return preparePostData.draftitemid;
+    }
+
+    /**
+     * Upload attachments for a reply that isn't an online post being edited.
+     *
+     * @param replyingTo Replying to post ID.
+     * @returns Draft area id (if any attachment was uploaded) and whether data should be saved offline.
+     */
+    async uploadAttachmentsForReply(
+        replyingTo: number,
+    ): Promise<{ attachments: CoreFileUploaderStoreFilesResult | number | undefined; saveOffline: boolean }> {
+        const files = this.formData.files || [];
+        if (!files.length) {
+            return { attachments: undefined, saveOffline: false };
+        }
+
+        try {
+            const attachments = await AddonModForumHelper.uploadOrStoreReplyFiles(
+                this.forum.id,
+                replyingTo,
+                files,
+                false,
+            );
+
+            return { attachments, saveOffline: false };
+        } catch (error) {
+            // Cannot upload them in online, save them in offline.
+            if (!this.forum.id || CoreUtils.isWebServiceError(error)) {
+                // Cannot store them in offline. Reject.
+                throw error;
+            }
+
+            const attachments = await AddonModForumHelper.uploadOrStoreReplyFiles(this.forum.id, replyingTo, files, true);
+
+            return { attachments, saveOffline: true };
+        }
+    }
+
     /**
      * Cancel reply.
      */