Initial implementation for local echo

Each HistoryView maintains a list of pending events. Each pending
message is validated from the homeserver with either the returned
EventId or the body of the message.

Currently there is no support to remove invalid messages.

Also some small refactoring:
    - ChatPage doesn't know about the message being sent. The message
      delivery is solely handled by HistoryViewManager.
    - Nick coloring function moved to HistoryViewManager.

10 files changed, 244 insertions, 48 deletions

diff --git a/include/ChatPage.h b/include/ChatPage.h
index d0edac3a..fd0b63dc 100644
--- a/include/ChatPage.h
+++ b/include/ChatPage.h
@@ -57,8 +57,6 @@ private slots:
 	void syncCompleted(const SyncResponse &response);
 	void syncFailed(const QString &msg);
 	void changeTopRoomInfo(const RoomInfo &info);
-	void sendTextMessage(const QString &msg);
-	void messageSent(const QString event_id, int txn_id);
 	void startSync();
 	void logout();
 
diff --git a/include/HistoryView.h b/include/HistoryView.h
index 9eb0783f..ba267ad4 100644
--- a/include/HistoryView.h
+++ b/include/HistoryView.h
@@ -27,6 +27,15 @@
 #include "HistoryViewItem.h"
 #include "Sync.h"
 
+// Contains info about a message shown in the history view
+// but not yet confirmed by the homeserver through sync.
+struct PendingMessage {
+	int txn_id;
+	QString body;
+	QString event_id;
+	HistoryViewItem *widget;
+};
+
 class HistoryView : public QWidget
 {
 	Q_OBJECT
@@ -38,6 +47,8 @@ public:
 
 	void addHistoryItem(const Event &event, const QString &color, bool with_sender);
 	void addEvents(const QList<Event> &events);
+	void addUserTextMessage(const QString &msg, int txn_id);
+	void updatePendingMessage(int txn_id, QString event_id);
 	void clear();
 
 public slots:
@@ -45,6 +56,8 @@ public slots:
 
 private:
 	void init();
+	void removePendingMessage(const Event &event);
+	bool isPendingMessage(const Event &event, const QString &userid);
 
 	QVBoxLayout *top_layout_;
 	QVBoxLayout *scroll_layout_;
@@ -53,6 +66,8 @@ private:
 	QWidget *scroll_widget_;
 
 	QString last_sender_;
+
+	QList<PendingMessage> pending_msgs_;
 };
 
 #endif  // HISTORY_VIEW_H
diff --git a/include/HistoryViewItem.h b/include/HistoryViewItem.h
index 2d93e451..e1ed3374 100644
--- a/include/HistoryViewItem.h
+++ b/include/HistoryViewItem.h
@@ -28,10 +28,22 @@ class HistoryViewItem : public QWidget
 {
 	Q_OBJECT
 public:
+	// For remote messages.
 	HistoryViewItem(const Event &event, bool with_sender, const QString &color, QWidget *parent = 0);
+
+	// For local messages.
+	HistoryViewItem(const QString &userid, const QString &color, const QString &body, QWidget *parent = 0);
+	HistoryViewItem(const QString &body, QWidget *parent = 0);
+
 	~HistoryViewItem();
 
 private:
+	void generateBody(const QString &body);
+	void generateBody(const QString &userid, const QString &color, const QString &body);
+	void generateTimestamp(const QDateTime &time);
+
+	void setupLayout();
+
 	QHBoxLayout *top_layout_;
 
 	QLabel *time_label_;
diff --git a/include/HistoryViewManager.h b/include/HistoryViewManager.h
index cdb20e98..9f07f064 100644
--- a/include/HistoryViewManager.h
+++ b/include/HistoryViewManager.h
@@ -19,10 +19,12 @@
 #define HISTORY_VIEW_MANAGER_H
 
 #include <QDebug>
+#include <QSharedPointer>
 #include <QStackedWidget>
 #include <QWidget>
 
 #include "HistoryView.h"
+#include "MatrixClient.h"
 #include "RoomInfo.h"
 #include "Sync.h"
 
@@ -31,7 +33,7 @@ class HistoryViewManager : public QStackedWidget
 	Q_OBJECT
 
 public:
-	HistoryViewManager(QWidget *parent);
+	HistoryViewManager(QSharedPointer<MatrixClient> client, QWidget *parent);
 	~HistoryViewManager();
 
 	void initialize(const Rooms &rooms);
@@ -39,14 +41,21 @@ public:
 	void clearAll();
 
 	static QString chooseRandomColor();
+	static QString getUserColor(const QString &userid);
 	static QMap<QString, QString> NICK_COLORS;
 	static const QList<QString> COLORS;
 
 public slots:
 	void setHistoryView(const RoomInfo &info);
+	void sendTextMessage(const QString &msg);
+
+private slots:
+	void messageSent(const QString &eventid, const QString &roomid, int txnid);
 
 private:
+	RoomInfo active_room_;
 	QMap<QString, HistoryView *> views_;
+	QSharedPointer<MatrixClient> client_;
 };
 
 #endif
diff --git a/include/MatrixClient.h b/include/MatrixClient.h
index 021a2594..8d517b9a 100644
--- a/include/MatrixClient.h
+++ b/include/MatrixClient.h
@@ -44,6 +44,7 @@ public:
 	void fetchOwnAvatar(const QUrl &avatar_url);
 
 	inline QString getHomeServer();
+	inline int transactionId();
 	inline void incrementTransactionId();
 
 	void reset() noexcept;
@@ -73,7 +74,7 @@ signals:
 	void initialSyncCompleted(const SyncResponse &response);
 	void syncCompleted(const SyncResponse &response);
 	void syncFailed(const QString &msg);
-	void messageSent(const QString &event_id, const int txn_id);
+	void messageSent(const QString &event_id, const QString &roomid, const int txn_id);
 
 private slots:
 	void onResponse(QNetworkReply *reply);
@@ -126,6 +127,11 @@ inline QString MatrixClient::getHomeServer()
 	return server_;
 }
 
+inline int MatrixClient::transactionId()
+{
+	return txn_id_;
+}
+
 inline void MatrixClient::setServer(const QString &server)
 {
 	server_ = "https://" + server;
diff --git a/src/ChatPage.cc b/src/ChatPage.cc
index 33f98af3..dfe1505e 100644
--- a/src/ChatPage.cc
+++ b/src/ChatPage.cc
@@ -39,7 +39,7 @@ ChatPage::ChatPage(QSharedPointer<MatrixClient> client, QWidget *parent)
 	top_bar_ = new TopRoomBar(this);
 	ui->topBarLayout->addWidget(top_bar_);
 
-	view_manager_ = new HistoryViewManager(this);
+	view_manager_ = new HistoryViewManager(client, this);
 	ui->mainContentLayout->addWidget(view_manager_);
 
 	text_input_ = new TextInputWidget(this);
@@ -66,7 +66,7 @@ ChatPage::ChatPage(QSharedPointer<MatrixClient> client, QWidget *parent)
 
 	connect(text_input_,
 		SIGNAL(sendTextMessage(const QString &)),
-		this,
+		view_manager_,
 		SLOT(sendTextMessage(const QString &)));
 
 	connect(client_.data(),
@@ -94,10 +94,6 @@ ChatPage::ChatPage(QSharedPointer<MatrixClient> client, QWidget *parent)
 		SIGNAL(ownAvatarRetrieved(const QPixmap &)),
 		this,
 		SLOT(setOwnAvatar(const QPixmap &)));
-	connect(client_.data(),
-		SIGNAL(messageSent(QString, int)),
-		this,
-		SLOT(messageSent(QString, int)));
 }
 
 void ChatPage::logout()
@@ -123,20 +119,6 @@ void ChatPage::logout()
 	emit close();
 }
 
-void ChatPage::messageSent(QString event_id, int txn_id)
-{
-	Q_UNUSED(event_id);
-
-	QSettings settings;
-	settings.setValue("client/transaction_id", txn_id + 1);
-}
-
-void ChatPage::sendTextMessage(const QString &msg)
-{
-	auto room = current_room_;
-	client_->sendTextMessage(current_room_.id(), msg);
-}
-
 void ChatPage::bootstrap(QString userid, QString homeserver, QString token)
 {
 	Q_UNUSED(userid);
diff --git a/src/HistoryView.cc b/src/HistoryView.cc
index ce2e2f6c..f1e19aec 100644
--- a/src/HistoryView.cc
+++ b/src/HistoryView.cc
@@ -17,6 +17,7 @@
 
 #include <QDebug>
 #include <QScrollBar>
+#include <QSettings>
 #include <QtWidgets/QLabel>
 #include <QtWidgets/QSpacerItem>
 
@@ -51,18 +52,21 @@ void HistoryView::sliderRangeChanged(int min, int max)
 
 void HistoryView::addEvents(const QList<Event> &events)
 {
+	QSettings settings;
+	auto local_user = settings.value("auth/user_id").toString();
+
 	for (const auto &event : events) {
 		if (event.type() == "m.room.message") {
 			auto msg_type = event.content().value("msgtype").toString();
 
+			if (isPendingMessage(event, local_user)) {
+				removePendingMessage(event);
+				continue;
+			}
+
 			if (msg_type == "m.text" || msg_type == "m.notice") {
 				auto with_sender = last_sender_ != event.sender();
-				auto color = HistoryViewManager::NICK_COLORS.value(event.sender());
-
-				if (color.isEmpty()) {
-					color = HistoryViewManager::chooseRandomColor();
-					HistoryViewManager::NICK_COLORS.insert(event.sender(), color);
-				}
+				auto color = HistoryViewManager::getUserColor(event.sender());
 
 				addHistoryItem(event, color, with_sender);
 				last_sender_ = event.sender();
@@ -103,11 +107,81 @@ void HistoryView::init()
 
 void HistoryView::addHistoryItem(const Event &event, const QString &color, bool with_sender)
 {
-	// TODO: Probably create another function instead of passing the flag.
 	HistoryViewItem *item = new HistoryViewItem(event, with_sender, color, scroll_widget_);
 	scroll_layout_->addWidget(item);
 }
 
+void HistoryView::updatePendingMessage(int txn_id, QString event_id)
+{
+	for (auto &msg : pending_msgs_) {
+		if (msg.txn_id == txn_id) {
+			msg.event_id = event_id;
+			break;
+		}
+	}
+}
+
+bool HistoryView::isPendingMessage(const Event &event, const QString &userid)
+{
+	if (event.sender() != userid || event.type() != "m.room.message")
+		return false;
+
+	auto msgtype = event.content().value("msgtype").toString();
+	auto body = event.content().value("body").toString();
+
+	// FIXME: should contain more checks later on for other types of messages.
+	if (msgtype != "m.text")
+		return false;
+
+	for (const auto &msg : pending_msgs_) {
+		if (msg.event_id == event.eventId() || msg.body == body)
+			return true;
+	}
+
+	return false;
+}
+
+void HistoryView::removePendingMessage(const Event &event)
+{
+	auto body = event.content().value("body").toString();
+
+	for (auto it = pending_msgs_.begin(); it != pending_msgs_.end(); it++) {
+		int index = std::distance(pending_msgs_.begin(), it);
+
+		if (it->event_id == event.eventId() || it->body == body) {
+			pending_msgs_.removeAt(index);
+			break;
+		}
+	}
+}
+
+void HistoryView::addUserTextMessage(const QString &body, int txn_id)
+{
+	QSettings settings;
+	auto user_id = settings.value("auth/user_id").toString();
+
+	auto with_sender = last_sender_ != user_id;
+	auto color = HistoryViewManager::getUserColor(user_id);
+
+	HistoryViewItem *view_item;
+
+	if (with_sender)
+		view_item = new HistoryViewItem(user_id, color, body, scroll_widget_);
+	else
+		view_item = new HistoryViewItem(body, scroll_widget_);
+
+	scroll_layout_->addWidget(view_item);
+
+	last_sender_ = user_id;
+
+	PendingMessage message = {};
+	message.txn_id = txn_id;
+	message.body = body;
+	message.widget = view_item;
+
+	pending_msgs_.push_back(message);
+}
+
 HistoryView::~HistoryView()
 {
 }
diff --git a/src/HistoryViewItem.cc b/src/HistoryViewItem.cc
index 8eb92372..83d3cf85 100644
--- a/src/HistoryViewItem.cc
+++ b/src/HistoryViewItem.cc
@@ -20,35 +20,63 @@
 
 #include "HistoryViewItem.h"
 
-HistoryViewItem::HistoryViewItem(const Event &event, bool with_sender, const QString &color, QWidget *parent)
+HistoryViewItem::HistoryViewItem(const QString &userid, const QString &color, const QString &body, QWidget *parent)
     : QWidget(parent)
 {
-	QString sender = "";
+	generateTimestamp(QDateTime::currentDateTime());
+	generateBody(userid, color, body);
+	setupLayout();
+}
 
-	if (with_sender)
-		sender = event.sender().split(":")[0].split("@")[1];
+HistoryViewItem::HistoryViewItem(const QString &body, QWidget *parent)
+    : QWidget(parent)
+{
+	generateTimestamp(QDateTime::currentDateTime());
+	generateBody(body);
+	setupLayout();
+}
 
-	auto body = event.content().value("body").toString().trimmed();
+HistoryViewItem::HistoryViewItem(const Event &event, bool with_sender, const QString &color, QWidget *parent)
+    : QWidget(parent)
+{
+	auto body = event.content().value("body").toString().trimmed().toHtmlEscaped();
 	auto timestamp = QDateTime::fromMSecsSinceEpoch(event.timestamp());
-	auto local_time = timestamp.toString("HH:mm");
+
+	generateTimestamp(timestamp);
 
 	if (event.content().value("msgtype").toString() == "m.notice")
 		body = "<i style=\"color: #565E5E\">" + body + "</i>";
 
-	time_label_ = new QLabel(this);
-	time_label_->setWordWrap(true);
-	QString msg(
+	if (with_sender)
+		generateBody(event.sender(), color, body);
+	else
+		generateBody(body);
+
+	setupLayout();
+}
+
+void HistoryViewItem::generateBody(const QString &body)
+{
+	content_label_ = new QLabel(this);
+	content_label_->setWordWrap(true);
+	content_label_->setAlignment(Qt::AlignTop);
+	content_label_->setStyleSheet("margin: 0;");
+	QString content(
 		"<html>"
 		"<head/>"
 		"<body>"
-		"   <span style=\"font-size: 7pt; color: #5d6565;\">"
+		"   <span style=\"font-size: 10pt; color: #B1AEA5;\">"
 		"   %1"
 		"   </span>"
 		"</body>"
 		"</html>");
-	time_label_->setText(msg.arg(local_time));
-	time_label_->setStyleSheet("margin-left: 7px; margin-right: 7px; margin-top: 0;");
-	time_label_->setAlignment(Qt::AlignTop);
+	content_label_->setText(content.arg(body));
+	content_label_->setTextInteractionFlags(Qt::TextSelectableByMouse);
+}
+
+void HistoryViewItem::generateBody(const QString &userid, const QString &color, const QString &body)
+{
+	auto sender = userid.split(":")[0].split("@")[1];
 
 	content_label_ = new QLabel(this);
 	content_label_->setWordWrap(true);
@@ -68,10 +96,41 @@ HistoryViewItem::HistoryViewItem(const Event &event, bool with_sender, const QSt
 		"</html>");
 	content_label_->setText(content.arg(color).arg(sender).arg(body));
 	content_label_->setTextInteractionFlags(Qt::TextSelectableByMouse);
+}
+
+void HistoryViewItem::generateTimestamp(const QDateTime &time)
+{
+	auto local_time = time.toString("HH:mm");
+
+	time_label_ = new QLabel(this);
+	QString msg(
+		"<html>"
+		"<head/>"
+		"<body>"
+		"   <span style=\"font-size: 7pt; color: #5d6565;\">"
+		"   %1"
+		"   </span>"
+		"</body>"
+		"</html>");
+	time_label_->setText(msg.arg(local_time));
+	time_label_->setStyleSheet("margin-left: 7px; margin-right: 7px; margin-top: 0;");
+	time_label_->setAlignment(Qt::AlignTop);
+}
+
+void HistoryViewItem::setupLayout()
+{
+	if (time_label_ == nullptr) {
+		qWarning() << "HistoryViewItem: Time label is not initialized";
+		return;
+	}
+
+	if (content_label_ == nullptr) {
+		qWarning() << "HistoryViewItem: Content label is not initialized";
+		return;
+	}
 
 	top_layout_ = new QHBoxLayout();
 	top_layout_->setMargin(0);
-
 	top_layout_->addWidget(time_label_);
 	top_layout_->addWidget(content_label_, 1);
 
diff --git a/src/HistoryViewManager.cc b/src/HistoryViewManager.cc
index a91dcc4f..706a42f1 100644
--- a/src/HistoryViewManager.cc
+++ b/src/HistoryViewManager.cc
@@ -18,14 +18,16 @@
 #include <random>
 
 #include <QDebug>
+#include <QSettings>
 #include <QStackedWidget>
 #include <QWidget>
 
 #include "HistoryView.h"
 #include "HistoryViewManager.h"
 
-HistoryViewManager::HistoryViewManager(QWidget *parent)
+HistoryViewManager::HistoryViewManager(QSharedPointer<MatrixClient> client, QWidget *parent)
     : QStackedWidget(parent)
+    , client_(client)
 {
 	setStyleSheet(
 		"QWidget {background: #171919; color: #ebebeb;}"
@@ -33,12 +35,36 @@ HistoryViewManager::HistoryViewManager(QWidget *parent)
 		"QScrollBar::handle:vertical { border-radius : 50px; background-color : #1c3133; }"
 		"QScrollBar::add-line:vertical { border: none; background: none; }"
 		"QScrollBar::sub-line:vertical { border: none; background: none; }");
+
+	connect(client_.data(),
+		SIGNAL(messageSent(const QString &, const QString &, int)),
+		this,
+		SLOT(messageSent(const QString &, const QString &, int)));
 }
 
 HistoryViewManager::~HistoryViewManager()
 {
 }
 
+void HistoryViewManager::messageSent(const QString &event_id, const QString &roomid, int txn_id)
+{
+	// We save the latest valid transaction ID for later use.
+	QSettings settings;
+	settings.setValue("client/transaction_id", txn_id + 1);
+
+	auto view = views_[roomid];
+	view->updatePendingMessage(txn_id, event_id);
+}
+
+void HistoryViewManager::sendTextMessage(const QString &msg)
+{
+	auto room = active_room_;
+	auto view = views_[room.id()];
+
+	view->addUserTextMessage(msg, client_->transactionId());
+	client_->sendTextMessage(room.id(), msg);
+}
+
 void HistoryViewManager::clearAll()
 {
 	NICK_COLORS.clear();
@@ -92,6 +118,7 @@ void HistoryViewManager::setHistoryView(const RoomInfo &info)
 		return;
 	}
 
+	active_room_ = info;
 	auto widget = views_.value(info.id());
 
 	setCurrentWidget(widget);
@@ -132,3 +159,15 @@ QString HistoryViewManager::chooseRandomColor()
 
 	return HistoryViewManager::COLORS[dist(engine)];
 }
+
+QString HistoryViewManager::getUserColor(const QString &userid)
+{
+	auto color = NICK_COLORS.value(userid);
+
+	if (color.isEmpty()) {
+		color = chooseRandomColor();
+		NICK_COLORS.insert(userid, color);
+	}
+
+	return color;
+}
diff --git a/src/MatrixClient.cc b/src/MatrixClient.cc
index 7b45646c..9299c7eb 100644
--- a/src/MatrixClient.cc
+++ b/src/MatrixClient.cc
@@ -258,9 +258,8 @@ void MatrixClient::onSendTextMessageResponse(QNetworkReply *reply)
 	}
 
 	emit messageSent(object.value("event_id").toString(),
+			 reply->property("roomid").toString(),
 			 reply->property("txn_id").toInt());
-
-	incrementTransactionId();
 }
 
 void MatrixClient::onRoomAvatarResponse(QNetworkReply *reply)
@@ -446,6 +445,9 @@ void MatrixClient::sendTextMessage(const QString &roomid, const QString &msg) no
 
 	reply->setProperty("endpoint", Endpoint::SendTextMessage);
 	reply->setProperty("txn_id", txn_id_);
+	reply->setProperty("roomid", roomid);
+
+	incrementTransactionId();
 }
 
 void MatrixClient::initialSync() noexcept