Poll data and updates handling added.

Telegram/SourceFiles/data/data_poll.cpp

@@ -0,0 +1,122 @@
+/*
+This file is part of Telegram Desktop,
+the official desktop application for the Telegram messaging service.
+
+For license and copyright information please follow this link:
+https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
+*/
+#include "data/data_poll.h"
+
+namespace {
+
+const PollAnswer *AnswerByOption(
+		const std::vector<PollAnswer> &list,
+		const QByteArray &option) {
+	const auto i = ranges::find(
+		list,
+		option,
+		[](const PollAnswer &a) { return a.option; });
+	return (i != end(list)) ? &*i : nullptr;
+}
+
+PollAnswer *AnswerByOption(
+		std::vector<PollAnswer> &list,
+		const QByteArray &option) {
+	return const_cast<PollAnswer*>(AnswerByOption(
+		std::as_const(list),
+		option));
+}
+
+} // namespace
+
+PollData::PollData(PollId id) : id(id) {
+}
+
+bool PollData::applyChanges(const MTPDpoll &poll) {
+	Expects(poll.vid.v == id);
+
+	const auto newQuestion = qs(poll.vquestion);
+	const auto newClosed = poll.is_closed();
+	auto newAnswers = ranges::view::all(
+		poll.vanswers.v
+	) | ranges::view::transform([](const MTPPollAnswer &data) {
+		return data.match([](const MTPDpollAnswer &answer) {
+			auto result = PollAnswer();
+			result.option = answer.voption.v;
+			result.text = qs(answer.vtext);
+			return result;
+		});
+	}) | ranges::to_vector;
+
+	const auto changed1 = (question != newQuestion)
+		|| (closed != newClosed);
+	const auto changed2 = (answers != newAnswers);
+	if (!changed1 && !changed2) {
+		return false;
+	}
+	if (changed1) {
+		question = newQuestion;
+		closed = newClosed;
+	}
+	if (changed2) {
+		std::swap(answers, newAnswers);
+		for (const auto &old : newAnswers) {
+			if (const auto current = answerByOption(old.option)) {
+				current->votes = old.votes;
+				current->chosen = old.chosen;
+			}
+		}
+	}
+	return true;
+}
+
+bool PollData::applyResults(const MTPPollResults &results) {
+	return results.match([&](const MTPDpollResults &results) {
+		const auto newTotalVoters = results.has_total_voters()
+			? results.vtotal_voters.v
+			: totalVoters;
+		auto changed = (newTotalVoters != totalVoters);
+		if (results.has_results()) {
+			for (const auto &result : results.vresults.v) {
+				if (applyResultToAnswers(result, results.is_min())) {
+					changed = true;
+				}
+			}
+		}
+		totalVoters = newTotalVoters;
+		return changed;
+	});
+}
+
+PollAnswer *PollData::answerByOption(const QByteArray &option) {
+	return AnswerByOption(answers, option);
+}
+
+const PollAnswer *PollData::answerByOption(const QByteArray &option) const {
+	return AnswerByOption(answers, option);
+}
+
+bool PollData::applyResultToAnswers(
+		const MTPPollAnswerVoters &result,
+		bool isMinResults) {
+	return result.match([&](const MTPDpollAnswerVoters &voters) {
+		const auto &option = voters.voption.v;
+		const auto answer = answerByOption(option);
+		if (!answer) {
+			return false;
+		}
+		auto changed = (answer->votes != voters.vvoters.v);
+		if (changed) {
+			answer->votes = voters.vvoters.v;
+		}
+		if (!isMinResults) {
+			if (answer->chosen != voters.is_chosen()) {
+				answer->chosen = voters.is_chosen();
+				changed = true;
+			}
+		} else if (const auto existing = answerByOption(option)) {
+			answer->chosen = existing->chosen;
+		}
+		return changed;
+	});
+}