MOBILE-4482 forum: Fix filtered content displayed when editing post

When editing a post, the editor displayed the content already filtered, and it could also include some exra content that doesn't belong to the post, like plagiarism info.

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

@@ -35,6 +35,7 @@ import {
     AddonModForumDiscussion,
     AddonModForumPost,
     AddonModForumPostFormData,
+    AddonModForumPrepareDraftAreaForPostWSResponse,
 } from '../../services/forum';
 import { CoreTag } from '@features/tag/services/tag';
 import { Translate } from '@singletons';
@@ -47,7 +48,7 @@ import { AddonModForumOffline } from '../../services/forum-offline';
 import { CoreUtils } from '@services/utils/utils';
 import { CoreRatingInfo } from '@features/rating/services/rating';
 import { CoreForms } from '@singletons/form';
-import { CoreFileEntry } from '@services/file-helper';
+import { CoreFileEntry, CoreFileHelper } from '@services/file-helper';
 import { AddonModForumSharedPostFormData } from '../../pages/discussion/discussion';
 import { CoreDom } from '@singletons/dom';
 import { CoreAnalytics, CoreAnalyticsEventType } from '@services/analytics';
@@ -95,6 +96,8 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
     displaySubject = true;
     optionsMenuEnabled = false;
 
+    protected preparePostData?: AddonModForumPrepareDraftAreaForPostWSResponse;
+
     constructor(
         protected elementRef: ElementRef,
     ) {}
@@ -226,6 +229,10 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
 
         // Show advanced fields if any of them has not the default value.
         this.advanced = this.formData.files.length > 0;
+
+        if (!isEditing || !postId || postId <= 0) {
+            this.preparePostData = undefined;
+        }
     }
 
     /**
@@ -314,6 +321,28 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
         // Ask confirm if there is unsaved data.
         try {
             await this.confirmDiscard();
+        } catch {
+            // Cancelled.
+            return;
+        }
+
+        const modal = await CoreLoadings.show();
+
+        try {
+            let message = this.post.message;
+
+            if (this.post.id > 0) {
+                // Call prepare post for edition to retrieve the message without any added content (like filters and plagiarism).
+                this.preparePostData = await AddonModForum.preparePostForEdition(this.post.id, 'post');
+
+                const { text } = CoreFileHelper.replaceDraftfileUrls(
+                    CoreSites.getRequiredCurrentSite().getURL(),
+                    this.preparePostData.messagetext,
+                    this.post.messageinlinefiles?.length ? this.post.messageinlinefiles : (this.preparePostData.files ?? []),
+                );
+
+                message = text;
+            }
 
             this.formData.syncId = AddonModForumSync.getDiscussionSyncId(this.discussionId);
             CoreSync.blockOperation(ADDON_MOD_FORUM_COMPONENT, this.formData.syncId);
@@ -322,7 +351,7 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
                 this.post.parentid,
                 true,
                 this.post.subject,
-                this.post.message,
+                message,
                 this.post.attachments,
                 this.post.isprivatereply,
                 this.post.id > 0 ? this.post.id : undefined,
@@ -331,8 +360,10 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
             this.scrollToForm();
 
             this.analyticsLogEvent('mod_forum_update_discussion_post', `/mod/forum/post.php?edit=${this.post.id}`);
-        } catch {
+        } catch (error) {
-            // Cancelled.
+            CoreDomUtils.showErrorModalDefault(error, 'addon.mod_forum.errorgetpost', true);
+        } finally {
+            modal.dismiss();
         }
     }
 
@@ -369,6 +400,16 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
         const isEditOnline = this.formData.id && this.formData.id > 0;
         const modal = await CoreLoadings.show('core.sending', true);
 
+        if (isEditOnline && this.preparePostData) {
+            // Restore the draft file URLs, otherwise the treated URLs would be saved in the content, which can cause problems.
+            message = CoreFileHelper.restoreDraftfileUrls(
+                CoreSites.getRequiredCurrentSite().getURL(),
+                message,
+                this.preparePostData.messagetext,
+                this.post.messageinlinefiles?.length ? this.post.messageinlinefiles : (this.preparePostData.files ?? []),
+            );
+        }
+
         // Add some HTML to the message if needed.
         message = CoreText.formatHtmlLines(message);
 
@@ -401,6 +442,7 @@ export class AddonModForumPostComponent implements OnInit, OnDestroy, OnChanges
             if (isEditOnline) {
                 sent = await AddonModForum.updatePost(this.formData.id!, subject, message, {
                     attachmentsid: attachments,
+                    inlineattachmentsid: this.preparePostData?.draftitemid,
                 });
             } else if (saveOffline) {
                 // Save post in offline.

src/addons/mod/forum/services/forum.ts

@@ -26,7 +26,13 @@ import { CoreGroups } from '@services/groups';
 import { CoreSitesCommonWSOptions, CoreSites, CoreSitesReadingStrategy } from '@services/sites';
 import { CoreUrl } from '@singletons/url';
 import { CoreUtils } from '@services/utils/utils';
-import { CoreStatusWithWarningsWSResponse, CoreWSExternalFile, CoreWSExternalWarning, CoreWSStoredFile } from '@services/ws';
+import {
+    CoreStatusWithWarningsWSResponse,
+    CoreWSExternalFile,
+    CoreWSExternalWarning,
+    CoreWSFile,
+    CoreWSStoredFile,
+} from '@services/ws';
 import { makeSingleton, Translate } from '@singletons';
 import { AddonModForumOffline, AddonModForumOfflineDiscussion, AddonModForumReplyOptions } from './forum-offline';
 import { CoreSiteWSPreSets } from '@classes/sites/authenticated-site';
@@ -606,7 +612,11 @@ export class AddonModForumProvider {
         };
 
         const site = await CoreSites.getSite(options.siteId);
+
         const isGetDiscussionPostsAvailable = this.isGetDiscussionPostsAvailable(site);
+        if (isGetDiscussionPostsAvailable && site.isVersionGreaterEqualThan('4.0')) {
+            (params as AddonModForumGetDiscussionPostsWSParams).includeinlineattachments = true;
+        }
 
         const response = isGetDiscussionPostsAvailable
             ? await site.read<AddonModForumGetDiscussionPostsWSResponse>('mod_forum_get_discussion_posts', params, preSets)
@@ -1264,6 +1274,35 @@ export class AddonModForumProvider {
         CoreUser.storeUsers(CoreUtils.objectToArray(users));
     }
 
+    /**
+     * Prepare post for edition.
+     *
+     * @param postId Post ID.
+     * @param area Area to prepare.
+     * @param options Other options.
+     * @returns Data of prepared area.
+     */
+    async preparePostForEdition(
+        postId: number,
+        area: 'attachment'|'post',
+        options: AddonModForumPreparePostOptions = {},
+    ): Promise<AddonModForumPrepareDraftAreaForPostWSResponse> {
+        const site = await CoreSites.getSite(options.siteId);
+
+        const params: AddonModForumPrepareDraftAreaForPostWSParams = {
+            postid: postId,
+            area: area,
+        };
+        if (options.filesToKeep?.length) {
+            params.filestokeep = options.filesToKeep.map(file => ({
+                filename: file.filename ?? '',
+                filepath: file.filepath ?? '',
+            }));
+        }
+
+        return await site.write('mod_forum_prepare_draft_area_for_post', params);
+    }
+
     /**
      * Update a certain post.
      *
@@ -1903,6 +1942,7 @@ export type AddonModForumGetDiscussionPostsWSParams = {
     discussionid: number; // The ID of the discussion from which to fetch posts.
     sortby?: string; // Sort by this element: id, created or modified.
     sortdirection?: string; // Sort direction: ASC or DESC.
+    includeinlineattachments?: boolean; // @since 4.0. Whether inline attachments should be included or not.
 };
 
 /**
@@ -2086,6 +2126,46 @@ export type AddonModForumUpdateDiscussionPostWSParams = {
  */
 export type AddonModForumUpdateDiscussionPostWSResponse = CoreStatusWithWarningsWSResponse;
 
+/**
+ * Params of mod_forum_prepare_draft_area_for_post WS.
+ */
+type AddonModForumPrepareDraftAreaForPostWSParams = {
+    postid: number; // Post to prepare the draft area for.
+    area: string; // Area to prepare: attachment or post.
+    draftitemid?: number; // The draft item id to use. 0 to generate one.
+    filestokeep?: AddonModForumFileToKeep[]; // Only keep these files in the draft file area. Empty for keeping all.
+};
+
+/**
+ * Data to pass to mod_forum_prepare_draft_area_for_post to keep a file in the area.
+ */
+type AddonModForumFileToKeep = {
+    filename: string; // File name.
+    filepath: string; // File path.
+};
+
+/**
+ * Data returned by mod_forum_prepare_draft_area_for_post WS.
+ */
+export type AddonModForumPrepareDraftAreaForPostWSResponse = {
+    draftitemid: number; // Draft item id for the file area.
+    files?: CoreWSExternalFile[];
+    areaoptions: { // Draft file area options.
+        name: string; // Name of option.
+        value: string; // Value of option.
+    }[];
+    messagetext: string; // Message text with URLs rewritten.
+    warnings?: CoreWSExternalWarning[];
+};
+
+/**
+ * Options to pass to preparePostForEdition.
+ */
+export type AddonModForumPreparePostOptions = {
+    filesToKeep?: CoreWSFile[]; // Only keep these files in the draft file area. Undefined or empty array for keeping all.
+    siteId?: string;
+};
+
 /**
  * Data passed to NEW_DISCUSSION_EVENT event.
  */