Initial support for read receipts

include/dialogs/ReadReceipts.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include <QDateTime>
+#include <QFrame>
+#include <QHBoxLayout>
+#include <QLabel>
+#include <QListWidget>
+#include <QVBoxLayout>
+
+class Avatar;
+
+namespace dialogs {
+
+class ReceiptItem : public QWidget
+{
+        Q_OBJECT
+
+public:
+        ReceiptItem(QWidget *parent, const QString &user_id, uint64_t timestamp);
+
+private:
+        QString dateFormat(const QDateTime &then) const;
+
+        QHBoxLayout *topLayout_;
+        QVBoxLayout *textLayout_;
+
+        Avatar *avatar_;
+
+        QLabel *userName_;
+        QLabel *timestamp_;
+};
+
+class ReadReceipts : public QFrame
+{
+        Q_OBJECT
+public:
+        explicit ReadReceipts(QWidget *parent = nullptr);
+
+public slots:
+        void addUsers(const std::multimap<uint64_t, std::string> &users);
+
+protected:
+        void paintEvent(QPaintEvent *event) override;
+
+private:
+        QLabel *topLabel_;
+
+        QListWidget *userList_;
+};
+} // dialogs