Chatedit: make default paste mode configurable

Many people like pasting plain text as there is less trouble with
it and does the job. Even Element pastes plain text by default
despite being a rich client. This is why this patch switches to
plain text pasting by default while makes it configurable.

Other version can be pasted by `Ctrl+Shift+V`.

Cc quotient-im#849

README.md

@@ -265,6 +265,8 @@ Settings not exposed in UI:
   is `false` since the current support of Markdown by Qt is buggy, and the whole
   functionality in Quaternion is, again, experimental. If you have it enabled
   (or use `/md` command) feel free to submit bug reports at the usual place.
+- `paste_plaintext_by_default` - set this to false (or 0) if you want to paste
+  formatted text by default.
 
 Since version 0.0.95, all Quaternion binaries at GitHub Releases are compiled
 with Qt Keychain support. It means that Quaternion will try to store your access

client/chatedit.cpp

@@ -37,13 +37,19 @@
 #include <util.h>
 
 static const QKeySequence ResetFormatShortcut("Ctrl+M");
+static const QKeySequence AlternatePasteShortcut("Ctrl+Shift+V");
 
 ChatEdit::ChatEdit(ChatRoomWidget* c)
     : KChatEdit(c), chatRoomWidget(c), matchesListPosition(0)
+    , m_pastePlaintext(pastePlaintextByDefault())
 {
     auto* sh = new QShortcut(this);
     sh->setKey(ResetFormatShortcut);
     connect(sh, &QShortcut::activated, this, &KChatEdit::resetCurrentFormat);
+
+    sh = new QShortcut(this);
+    sh->setKey(AlternatePasteShortcut);
+    connect(sh, &QShortcut::activated, this, &ChatEdit::alternatePaste);
 }
 
 void ChatEdit::keyPressEvent(QKeyEvent* event)
@@ -70,6 +76,22 @@ void ChatEdit::contextMenuEvent(QContextMenuEvent *event)
     connect(action, &QAction::triggered, this, &KChatEdit::resetCurrentFormat);
     menu->addAction(action);
 
+    action = new QAction(QIcon::fromTheme("edit-paste"),
+                         tr(pastePlaintextByDefault() ? "Paste as rich text"
+                                                      : "Paste as plain text"),
+                         this);
+    action->setShortcut(AlternatePasteShortcut);
+    connect(action, &QAction::triggered, this, &ChatEdit::alternatePaste);
+    bool insert = false;
+    for (QAction* a: menu->actions()) {
+        if (insert) {
+            menu->insertAction(a, action);
+            break;
+        }
+        if (a->objectName() == QStringLiteral("edit-paste"))
+            insert = true;
+    }
+
     menu->setAttribute(Qt::WA_DeleteOnClose);
     menu->popup(event->globalPos());
 }
@@ -85,6 +107,13 @@ bool ChatEdit::canInsertFromMimeData(const QMimeData *source) const
     return source->hasImage() || KChatEdit::canInsertFromMimeData(source);
 }
 
+void ChatEdit::alternatePaste()
+{
+    m_pastePlaintext = !pastePlaintextByDefault();
+    paste();
+    m_pastePlaintext = pastePlaintextByDefault();
+}
+
 void ChatEdit::insertFromMimeData(const QMimeData *source)
 {
     if (!source) {
@@ -93,19 +122,25 @@ void ChatEdit::insertFromMimeData(const QMimeData *source)
     }
 
     if (source->hasHtml()) {
-        // Before insertion, remove formatting unsupported in Matrix
-        const auto [cleanHtml, errorPos, errorString] =
-            HtmlFilter::fromLocalHtml(source->html());
-        if (errorPos != -1) {
-            qWarning() << "HTML insertion failed at pos" << errorPos
-                       << "with error" << errorString;
-            // FIXME: Come on... It should be app->showStatusMessage() or smth
-            emit chatRoomWidget->timelineWidget()->showStatusMessage(
-                tr("Could not insert HTML - it's either invalid or unsupported"),
-                5000);
-            return;
+        if (m_pastePlaintext) {
+            QTextDocument document;
+            document.setHtml(source->html());
+            insertPlainText(document.toPlainText());
+        } else {
+            // Before insertion, remove formatting unsupported in Matrix
+            const auto [cleanHtml, errorPos, errorString] =
+                HtmlFilter::fromLocalHtml(source->html());
+            if (errorPos != -1) {
+                qWarning() << "HTML insertion failed at pos" << errorPos
+                        << "with error" << errorString;
+                // FIXME: Come on... It should be app->showStatusMessage() or smth
+                emit chatRoomWidget->timelineWidget()->showStatusMessage(
+                    tr("Could not insert HTML - it's either invalid or unsupported"),
+                    5000);
+                return;
+            }
+            insertHtml(cleanHtml);
         }
-        insertHtml(cleanHtml);
         ensureCursorVisible();
     } else if (source->hasImage())
         emit insertImageRequested(source->imageData().value<QImage>());
@@ -272,3 +307,8 @@ void ChatEdit::insertMention(QString author, QUrl url)
     pickingMentions = true;
     cancelCompletion();
 }
+
+bool ChatEdit::pastePlaintextByDefault()
+{
+    return Quotient::Settings().get("UI/paste_plaintext_by_default", true);
+}

client/chatedit.h

@@ -41,6 +41,7 @@ class ChatEdit : public KChatEdit
 
     public slots:
         void switchContext(QObject* contextKey) override;
+        void alternatePaste();
 
     signals:
         void proposedCompletion(const QStringList& allCompletions, int curIndex);
@@ -61,6 +62,7 @@ class ChatEdit : public KChatEdit
         int matchesListPosition;
 
         bool pickingMentions = false;
+        bool m_pastePlaintext;
 
         /// \brief Initialise a new completion
         ///
@@ -71,6 +73,7 @@ class ChatEdit : public KChatEdit
                              QUrl mentionUrl, bool select);
         void keyPressEvent(QKeyEvent* event) override;
         void contextMenuEvent(QContextMenuEvent* event) override;
+        bool pastePlaintextByDefault();
 };