/*
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 "calls/calls_choose_join_as.h"

#include "calls/calls_group_common.h"
#include "data/data_peer.h"
#include "data/data_user.h"
#include "data/data_channel.h"
#include "data/data_session.h"
#include "data/data_group_call.h"
#include "main/main_session.h"
#include "main/main_account.h"
#include "lang/lang_keys.h"
#include "apiwrap.h"
#include "ui/layers/generic_box.h"
#include "ui/text/text_utilities.h"
#include "boxes/peer_list_box.h"
#include "boxes/confirm_box.h"
#include "styles/style_boxes.h"
#include "styles/style_calls.h"

namespace Calls::Group {
namespace {

using Context = ChooseJoinAsProcess::Context;

class ListController : public PeerListController {
public:
	ListController(
		std::vector<not_null<PeerData*>> list,
		not_null<PeerData*> selected);

	Main::Session &session() const override;
	void prepare() override;
	void rowClicked(not_null<PeerListRow*> row) override;

	[[nodiscard]] not_null<PeerData*> selected() const;

private:
	std::unique_ptr<PeerListRow> createRow(not_null<PeerData*> peer);

	std::vector<not_null<PeerData*>> _list;
	not_null<PeerData*> _selected;

};

ListController::ListController(
	std::vector<not_null<PeerData*>> list,
	not_null<PeerData*> selected)
: PeerListController()
, _list(std::move(list))
, _selected(selected) {
}

Main::Session &ListController::session() const {
	return _selected->session();
}

std::unique_ptr<PeerListRow> ListController::createRow(
		not_null<PeerData*> peer) {
	auto result = std::make_unique<PeerListRow>(peer);
	if (peer->isSelf()) {
		result->setCustomStatus(
			tr::lng_group_call_join_as_personal(tr::now));
	} else if (const auto channel = peer->asChannel()) {
		result->setCustomStatus(
			(channel->isMegagroup()
				? tr::lng_chat_status_members
				: tr::lng_chat_status_subscribers)(
					tr::now,
					lt_count,
					channel->membersCount()));
	}
	return result;
}

void ListController::prepare() {
	delegate()->peerListSetSearchMode(PeerListSearchMode::Disabled);
	for (const auto &peer : _list) {
		auto row = createRow(peer);
		const auto raw = row.get();
		delegate()->peerListAppendRow(std::move(row));
		if (peer == _selected) {
			delegate()->peerListSetRowChecked(raw, true);
			raw->finishCheckedAnimation();
		}
	}
	delegate()->peerListRefreshRows();
}

void ListController::rowClicked(not_null<PeerListRow*> row) {
	const auto peer = row->peer();
	if (peer == _selected) {
		return;
	}
	const auto previous = delegate()->peerListFindRow(_selected->id);
	Assert(previous != nullptr);
	delegate()->peerListSetRowChecked(previous, false);
	delegate()->peerListSetRowChecked(row, true);
	_selected = peer;
}

not_null<PeerData*> ListController::selected() const {
	return _selected;
}

void ChooseJoinAsBox(
		not_null<Ui::GenericBox*> box,
		Context context,
		JoinInfo info,
		Fn<void(JoinInfo)> done) {
	box->setWidth(st::groupCallJoinAsWidth);
	box->setTitle([&] {
		switch (context) {
		case Context::Create: return tr::lng_group_call_start_as_header();
		case Context::Join:
		case Context::JoinWithConfirm: return tr::lng_group_call_join_as_header();
		case Context::Switch: return tr::lng_group_call_display_as_header();
		}
		Unexpected("Context in ChooseJoinAsBox.");
	}());
	box->addRow(object_ptr<Ui::FlatLabel>(
		box,
		tr::lng_group_call_join_as_about(),
		(context == Context::Switch
			? st::groupCallJoinAsLabel
			: st::confirmPhoneAboutLabel)));

	auto &lifetime = box->lifetime();
	const auto delegate = lifetime.make_state<
		PeerListContentDelegateSimple
	>();
	const auto controller = lifetime.make_state<ListController>(
		info.possibleJoinAs,
		info.joinAs);
	if (context == Context::Switch) {
		controller->setStyleOverrides(
			&st::groupCallJoinAsList,
			&st::groupCallMultiSelect);
	} else {
		controller->setStyleOverrides(
			&st::peerListJoinAsList,
			nullptr);
	}
	const auto content = box->addRow(
		object_ptr<PeerListContent>(box, controller),
		style::margins());
	delegate->setContent(content);
	controller->setDelegate(delegate);
	auto next = (context == Context::Switch)
		? tr::lng_settings_save()
		: tr::lng_continue();
	box->addButton(std::move(next), [=] {
		auto copy = info;
		copy.joinAs = controller->selected();
		done(std::move(copy));
	});
	box->addButton(tr::lng_cancel(), [=] { box->closeBox(); });
}

} // namespace

ChooseJoinAsProcess::~ChooseJoinAsProcess() {
	if (_request) {
		_request->peer->session().api().request(_request->id).cancel();
	}
}

void ChooseJoinAsProcess::start(
		not_null<PeerData*> peer,
		Context context,
		Fn<void(object_ptr<Ui::BoxContent>)> showBox,
		Fn<void(QString)> showToast,
		Fn<void(JoinInfo)> done,
		PeerData *changingJoinAsFrom) {
	Expects(done != nullptr);

	const auto session = &peer->session();
	if (_request) {
		if (_request->peer == peer) {
			_request->context = context;
			_request->showBox = std::move(showBox);
			_request->showToast = std::move(showToast);
			_request->done = std::move(done);
			return;
		}
		session->api().request(_request->id).cancel();
		_request = nullptr;
	}
	_request = std::make_unique<ChannelsListRequest>(
		ChannelsListRequest{
			.peer = peer,
			.showBox = std::move(showBox),
			.showToast = std::move(showToast),
			.done = std::move(done),
			.context = context });
	session->account().sessionChanges(
	) | rpl::start_with_next([=] {
		_request = nullptr;
	}, _request->lifetime);

	const auto finish = [=](JoinInfo info) {
		const auto peer = _request->peer;
		const auto done = std::move(_request->done);
		const auto box = _request->box;
		_request = nullptr;
		done(std::move(info));
		if (const auto strong = box.data()) {
			strong->closeBox();
		}
	};
	_request->id = session->api().request(MTPphone_GetGroupCallJoinAs(
		_request->peer->input
	)).done([=](const MTPphone_JoinAsPeers &result) {
		const auto peer = _request->peer;
		const auto self = peer->session().user();
		auto info = JoinInfo{ .peer = peer, .joinAs = self };
		auto list = result.match([&](const MTPDphone_joinAsPeers &data) {
			session->data().processUsers(data.vusers());
			session->data().processChats(data.vchats());
			const auto &peers = data.vpeers().v;
			auto list = std::vector<not_null<PeerData*>>();
			list.reserve(peers.size());
			for (const auto &peer : peers) {
				const auto peerId = peerFromMTP(peer);
				if (const auto peer = session->data().peerLoaded(peerId)) {
					if (!ranges::contains(list, not_null{ peer })) {
						list.push_back(peer);
					}
				}
			}
			return list;
		});
		const auto selectedId = peer->groupCallDefaultJoinAs();
		if (list.empty()) {
			_request->showToast(Lang::Hard::ServerError());
			return;
		}
		info.joinAs = [&]() -> not_null<PeerData*> {
			const auto loaded = selectedId
				? session->data().peerLoaded(selectedId)
				: nullptr;
			return (changingJoinAsFrom
				&& ranges::contains(list, not_null{ changingJoinAsFrom }))
				? not_null(changingJoinAsFrom)
				: (loaded && ranges::contains(list, not_null{ loaded }))
				? not_null(loaded)
				: ranges::contains(list, self)
				? self
				: list.front();
		}();
		info.possibleJoinAs = std::move(list);

		const auto onlyByMe = (info.possibleJoinAs.size() == 1)
			&& (info.possibleJoinAs.front() == self)
			&& (!peer->isChannel()
				|| !peer->asChannel()->amAnonymous()
				|| (peer->isBroadcast() && !peer->canWrite()));

		// We already joined this voice chat, just rejoin with the same.
		const auto byAlreadyUsed = selectedId
			&& (info.joinAs->id == selectedId);

		if (!changingJoinAsFrom && (onlyByMe || byAlreadyUsed)) {
			if (context != Context::JoinWithConfirm) {
				finish(info);
				return;
			}
			const auto real = peer->groupCall();
			const auto name = (real && !real->title().isEmpty())
				? real->title()
				: peer->name;
			auto box = Box<::ConfirmBox>(
				tr::lng_group_call_join_confirm(
					tr::now,
					lt_chat,
					Ui::Text::Bold(name),
					Ui::Text::WithEntities),
				tr::lng_group_call_join(tr::now),
				crl::guard(&_request->guard, [=] { finish(info); }));
			box->boxClosing(
			) | rpl::start_with_next([=] {
				_request = nullptr;
			}, _request->lifetime);

			_request->box = box.data();
			_request->showBox(std::move(box));
			return;
		}
		auto box = Box(
			ChooseJoinAsBox,
			context,
			std::move(info),
			crl::guard(&_request->guard, finish));
		box->boxClosing(
		) | rpl::start_with_next([=] {
			_request = nullptr;
		}, _request->lifetime);

		_request->box = box.data();
		_request->showBox(std::move(box));
	}).fail([=](const MTP::Error &error) {
		finish({
			.peer = _request->peer,
			.joinAs = _request->peer->session().user(),
		});
	}).send();
}

} // namespace Calls::Group