Generate correct links to replies section.

Telegram/SourceFiles/apiwrap.cpp

@@ -683,17 +683,57 @@ void ApiWrap::finalizeMessageDataRequest(
 	}
 }
 
-QString ApiWrap::exportDirectMessageLink(not_null<HistoryItem*> item) {
+QString ApiWrap::exportDirectMessageLink(
+		not_null<HistoryItem*> item,
+		bool inRepliesContext) {
 	Expects(item->history()->peer->isChannel());
 
 	const auto itemId = item->fullId();
 	const auto channel = item->history()->peer->asChannel();
 	const auto fallback = [&] {
-		const auto base = channel->hasUsername()
+		auto linkChannel = channel;
-			? channel->username
+		auto linkItemId = item->id;
-			: "c/" + QString::number(channel->bareId());
+		auto linkCommentId = 0;
-		const auto query = base + '/' + QString::number(item->id);
+		auto linkThreadId = 0;
-		if (channel->hasUsername() && !channel->isMegagroup()) {
+		if (inRepliesContext) {
+			if (const auto rootId = item->replyToTop()) {
+				const auto root = item->history()->owner().message(
+					channel->bareId(),
+					rootId);
+				const auto sender = root
+					? root->discussionPostOriginalSender()
+					: nullptr;
+				if (sender && sender->hasUsername()) {
+					// Comment to a public channel.
+					const auto forwarded = root->Get<HistoryMessageForwarded>();
+					linkItemId = forwarded->savedFromMsgId;
+					if (linkItemId) {
+						linkChannel = sender;
+						linkCommentId = item->id;
+					} else {
+						linkItemId = item->id;
+					}
+				} else {
+					// Reply in a thread, maybe comment in a private channel.
+					linkThreadId = rootId;
+				}
+			}
+		}
+		const auto base = linkChannel->hasUsername()
+			? linkChannel->username
+			: "c/" + QString::number(linkChannel->bareId());
+		const auto query = base
+			+ '/'
+			+ QString::number(linkItemId)
+			+ (linkCommentId
+				? "?comment=" + QString::number(linkCommentId)
+				: linkThreadId
+				? "?thread=" + QString::number(linkThreadId)
+				: "");
+		if (linkChannel->hasUsername()
+			&& !linkChannel->isMegagroup()
+			&& !linkCommentId
+			&& !linkThreadId) {
 			if (const auto media = item->media()) {
 				if (const auto document = media->document()) {
 					if (document->isVideoMessage()) {
@@ -709,7 +749,9 @@ QString ApiWrap::exportDirectMessageLink(not_null<HistoryItem*> item) {
 		? i->second
 		: fallback();
 	request(MTPchannels_ExportMessageLink(
-		MTP_flags(0),
+		MTP_flags(inRepliesContext
+			? MTPchannels_ExportMessageLink::Flag::f_thread
+			: MTPchannels_ExportMessageLink::Flag(0)),
 		channel->inputChannel,
 		MTP_int(item->id)
 	)).done([=](const MTPExportedMessageLink &result) {

Telegram/SourceFiles/apiwrap.h

@@ -172,7 +172,9 @@ public:
 		ChannelData *channel,
 		MsgId msgId,
 		RequestMessageDataCallback callback);
-	QString exportDirectMessageLink(not_null<HistoryItem*> item);
+	QString exportDirectMessageLink(
+		not_null<HistoryItem*> item,
+		bool inRepliesContext);
 
 	void requestContacts();
 	void requestDialogs(Data::Folder *folder = nullptr);

Telegram/SourceFiles/history/history_inner_widget.cpp

@@ -1647,7 +1647,7 @@ void HistoryInner::showContextMenu(QContextMenuEvent *e, bool showFromTouch) {
 		}
 		if (item && item->hasDirectLink() && isUponSelected != 2 && isUponSelected != -2) {
 			_menu->addAction(item->history()->peer->isMegagroup() ? tr::lng_context_copy_link(tr::now) : tr::lng_context_copy_post_link(tr::now), [=] {
-				HistoryView::CopyPostLink(session, itemId);
+				HistoryView::CopyPostLink(session, itemId, HistoryView::Context::History);
 			});
 		}
 		if (isUponSelected > 1) {
@@ -1792,7 +1792,7 @@ void HistoryInner::showContextMenu(QContextMenuEvent *e, bool showFromTouch) {
 				});
 		} else if (item && item->hasDirectLink() && isUponSelected != 2 && isUponSelected != -2) {
 			_menu->addAction(item->history()->peer->isMegagroup() ? tr::lng_context_copy_link(tr::now) : tr::lng_context_copy_post_link(tr::now), [=] {
-				HistoryView::CopyPostLink(session, itemId);
+				HistoryView::CopyPostLink(session, itemId, HistoryView::Context::History);
 			});
 		}
 		if (isUponSelected > 1) {

Telegram/SourceFiles/history/history_message.cpp

@@ -218,7 +218,10 @@ void FastShareMessage(not_null<HistoryItem*> item) {
 	auto copyCallback = [=]() {
 		if (const auto item = owner->message(data->msgIds[0])) {
 			if (item->hasDirectLink()) {
-				HistoryView::CopyPostLink(session, item->fullId());
+				HistoryView::CopyPostLink(
+					session,
+					item->fullId(),
+					HistoryView::Context::History);
 			} else if (const auto bot = item->getMessageBot()) {
 				if (const auto media = item->media()) {
 					if (const auto game = media->game()) {

Telegram/SourceFiles/history/view/history_view_context_menu.cpp

@@ -254,11 +254,14 @@ void AddPostLinkAction(
 	}
 	const auto session = &item->history()->session();
 	const auto itemId = item->fullId();
+	const auto context = request.view
+		? request.view->context()
+		: Context::History;
 	menu->addAction(
 		(item->history()->peer->isMegagroup()
 			? tr::lng_context_copy_link
 			: tr::lng_context_copy_post_link)(tr::now),
-		[=] { CopyPostLink(session, itemId); });
+		[=] { CopyPostLink(session, itemId, context); });
 }
 
 MessageIdsList ExtractIdsList(const SelectedItems &items) {
@@ -774,18 +777,38 @@ base::unique_qptr<Ui::PopupMenu> FillContextMenu(
 	return result;
 }
 
-void CopyPostLink(not_null<Main::Session*> session, FullMsgId itemId) {
+void CopyPostLink(
+		not_null<Main::Session*> session,
+		FullMsgId itemId,
+		Context context) {
 	const auto item = session->data().message(itemId);
 	if (!item || !item->hasDirectLink()) {
 		return;
 	}
+	const auto inRepliesContext = (context == Context::Replies);
 	QGuiApplication::clipboard()->setText(
-		item->history()->session().api().exportDirectMessageLink(item));
+		item->history()->session().api().exportDirectMessageLink(
+			item,
+			inRepliesContext));
 
+	const auto isPublicLink = [&] {
 		const auto channel = item->history()->peer->asChannel();
 		Assert(channel != nullptr);
+		if (const auto rootId = item->replyToTop()) {
+			const auto root = item->history()->owner().message(
+				channel->bareId(),
+				rootId);
+			const auto sender = root
+				? root->discussionPostOriginalSender()
+				: nullptr;
+			if (sender && sender->hasUsername()) {
+				return true;
+			}
+		}
+		return channel->hasUsername();
+	}();
 
-	Ui::Toast::Show(channel->hasUsername()
+	Ui::Toast::Show(isPublicLink
 		? tr::lng_channel_public_link_copied(tr::now)
 		: tr::lng_context_about_private_link(tr::now));
 }

Telegram/SourceFiles/history/view/history_view_context_menu.h

@@ -19,6 +19,7 @@ class SessionNavigation;
 
 namespace HistoryView {
 
+enum class Context : char;
 enum class PointState : char;
 class ListWidget;
 class Element;
@@ -43,7 +44,10 @@ base::unique_qptr<Ui::PopupMenu> FillContextMenu(
 	not_null<ListWidget*> list,
 	const ContextMenuRequest &request);
 
-void CopyPostLink(not_null<Main::Session*> session, FullMsgId itemId);
+void CopyPostLink(
+	not_null<Main::Session*> session,
+	FullMsgId itemId,
+	Context context);
 void StopPoll(not_null<Main::Session*> session, FullMsgId itemId);
 
 } // namespace