From 2bf612c02027bc9dc1aff3ce75ca7cfb03034cea Mon Sep 17 00:00:00 2001
From: levlam <levlam@telegram.org>
Date: Mon, 19 Jun 2023 18:45:56 +0300
Subject: [PATCH] Add MessageViewers::get_sublist.

---
 td/telegram/MessageViewer.cpp | 24 ++++++++++++++++++++++++
 td/telegram/MessageViewer.h   |  8 ++++++++
 2 files changed, 32 insertions(+)

diff --git a/td/telegram/MessageViewer.cpp b/td/telegram/MessageViewer.cpp
index 883c6f0d4..74ff5f29d 100644
--- a/td/telegram/MessageViewer.cpp
+++ b/td/telegram/MessageViewer.cpp
@@ -22,6 +22,14 @@ td_api::object_ptr<td_api::messageViewer> MessageViewer::get_message_viewer_obje
       contacts_manager->get_user_id_object(user_id_, "get_message_viewer_object"), date_);
 }
 
+bool operator==(const MessageViewer &lhs, const MessageViewer &rhs) {
+  return lhs.user_id_ == rhs.user_id_ && lhs.date_ == rhs.date_;
+}
+
+bool operator!=(const MessageViewer &lhs, const MessageViewer &rhs) {
+  return !(lhs == rhs);
+}
+
 StringBuilder &operator<<(StringBuilder &string_builder, const MessageViewer &viewer) {
   return string_builder << '[' << viewer.user_id_ << " at " << viewer.date_ << ']';
 }
@@ -44,6 +52,22 @@ MessageViewers::MessageViewers(vector<telegram_api::object_ptr<telegram_api::rea
           })) {
 }
 
+MessageViewers MessageViewers::get_sublist(const MessageViewer &offset, int32 limit) const {
+  MessageViewers result{vector<telegram_api::object_ptr<telegram_api::storyView>>()};
+  bool found = offset == MessageViewer(UserId(), 0);
+  for (auto &message_viewer : message_viewers_) {
+    if (found) {
+      if (limit-- <= 0) {
+        break;
+      }
+      result.message_viewers_.push_back(message_viewer);
+    } else if (message_viewer == offset) {
+      found = true;
+    }
+  }
+  return result;
+}
+
 td_api::object_ptr<td_api::messageViewers> MessageViewers::get_message_viewers_object(
     ContactsManager *contacts_manager) const {
   return td_api::make_object<td_api::messageViewers>(
diff --git a/td/telegram/MessageViewer.h b/td/telegram/MessageViewer.h
index 4eb2bce0f..06a39c57f 100644
--- a/td/telegram/MessageViewer.h
+++ b/td/telegram/MessageViewer.h
@@ -23,6 +23,8 @@ class MessageViewer {
 
   friend StringBuilder &operator<<(StringBuilder &string_builder, const MessageViewer &viewer);
 
+  friend bool operator==(const MessageViewer &lhs, const MessageViewer &rhs);
+
  public:
   explicit MessageViewer(telegram_api::object_ptr<telegram_api::readParticipantDate> &&read_date);
 
@@ -36,6 +38,10 @@ class MessageViewer {
   td_api::object_ptr<td_api::messageViewer> get_message_viewer_object(ContactsManager *contacts_manager) const;
 };
 
+bool operator==(const MessageViewer &lhs, const MessageViewer &rhs);
+
+bool operator!=(const MessageViewer &lhs, const MessageViewer &rhs);
+
 StringBuilder &operator<<(StringBuilder &string_builder, const MessageViewer &viewer);
 
 struct MessageViewers {
@@ -45,6 +51,8 @@ struct MessageViewers {
 
   explicit MessageViewers(vector<telegram_api::object_ptr<telegram_api::readParticipantDate>> &&read_dates);
 
+  MessageViewers get_sublist(const MessageViewer &offset, int32 limit) const;
+
   td_api::object_ptr<td_api::messageViewers> get_message_viewers_object(ContactsManager *contacts_manager) const;
 };