tdesktop/Telegram/SourceFiles/history/history_admin_log_inner.h

/*
This file is part of Telegram Desktop,
the official desktop version of Telegram messaging app, see https://telegram.org

Telegram Desktop is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

It is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

In addition, as a special exception, the copyright holders give permission
to link the code of portions of this program with the OpenSSL library.

Full license: https://github.com/telegramdesktop/tdesktop/blob/master/LICENSE
Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
*/
#pragma once

#include "history/history_admin_log_item.h"
#include "ui/widgets/tooltip.h"
#include "mtproto/sender.h"
#include "base/timer.h"

namespace Ui {
class PopupMenu;
} // namespace Ui

namespace Window {
class Controller;
} // namespace Window

namespace AdminLog {

class SectionMemento;

class LocalIdManager {
public:
	LocalIdManager() = default;
	LocalIdManager(const LocalIdManager &other) = delete;
	LocalIdManager &operator=(const LocalIdManager &other) = delete;
	LocalIdManager(LocalIdManager &&other) : _counter(std::exchange(other._counter, ServerMaxMsgId)) {
	}
	LocalIdManager &operator=(LocalIdManager &&other) {
		_counter = std::exchange(other._counter, ServerMaxMsgId);
		return *this;
	}
	MsgId next() {
		return ++_counter;
	}

private:
	MsgId _counter = ServerMaxMsgId;

};

class InnerWidget final : public TWidget, public Ui::AbstractTooltipShower, private MTP::Sender, private base::Subscriber {
public:
	InnerWidget(QWidget *parent, gsl::not_null<Window::Controller*> controller, gsl::not_null<ChannelData*> channel, base::lambda<void(int top)> scrollTo);

	gsl::not_null<ChannelData*> channel() const {
		return _channel;
	}

	// Updates the area that is visible inside the scroll container.
	void setVisibleTopBottom(int visibleTop, int visibleBottom) override;

	void resizeToWidth(int newWidth, int minHeight) {
		_minHeight = minHeight;
		return TWidget::resizeToWidth(newWidth);
	}

	void saveState(gsl::not_null<SectionMemento*> memento) const;
	void restoreState(gsl::not_null<const SectionMemento*> memento);
	void setCancelledCallback(base::lambda<void()> callback) {
		_cancelledCallback = std::move(callback);
	}

	// Empty "flags" means all events. Empty "admins" means all admins.
	void applyFilter(MTPDchannelAdminLogEventsFilter::Flags flags, const std::vector<gsl::not_null<UserData*>> &admins);

	// AbstractTooltipShower interface
	QString tooltipText() const override;
	QPoint tooltipPos() const override;

	~InnerWidget();

protected:
	void paintEvent(QPaintEvent *e) override;
	void keyPressEvent(QKeyEvent *e) override;
	void mousePressEvent(QMouseEvent *e) override;
	void mouseMoveEvent(QMouseEvent *e) override;
	void mouseReleaseEvent(QMouseEvent *e) override;
	void enterEventHook(QEvent *e) override;
	void leaveEventHook(QEvent *e) override;

	// Resizes content and counts natural widget height for the desired width.
	int resizeGetHeight(int newWidth) override;

private:
	enum class Direction {
		Up,
		Down,
	};
	enum class MouseAction {
		None,
		PrepareDrag,
		Dragging,
		Selecting,
	};

	void mouseActionStart(const QPoint &screenPos, Qt::MouseButton button);
	void mouseActionUpdate(const QPoint &screenPos);
	void mouseActionFinish(const QPoint &screenPos, Qt::MouseButton button);
	void mouseActionCancel();
	void updateSelected();
	void performDrag();
	int itemTop(gsl::not_null<const HistoryItem*> item) const;
	void repaintItem(const HistoryItem *item);
	QPoint mapPointToItem(QPoint point, const HistoryItem *item) const;
	void handlePendingHistoryResize();

	void checkPreloadMore();
	void updateVisibleTopItem();
	void preloadMore(Direction direction);
	void itemsAdded(Direction direction);
	void updateSize();
	void paintEmpty(Painter &p);

	void toggleScrollDateShown();
	void repaintScrollDateCallback();
	bool displayScrollDate() const;
	void scrollDateHide();
	void keepScrollDateForNow();
	void scrollDateCheck();
	void scrollDateHideByTimer();

	gsl::not_null<Window::Controller*> _controller;
	gsl::not_null<ChannelData*> _channel;
	gsl::not_null<History*> _history;
	base::lambda<void()> _cancelledCallback;
	base::lambda<void(int top)> _scrollTo;
	std::vector<HistoryItemOwned> _items;
	std::map<uint64, HistoryItem*> _itemsByIds;
	int _itemsTop = 0;
	int _itemsHeight = 0;

	LocalIdManager _idManager;
	int _minHeight = 0;
	int _visibleTop = 0;
	int _visibleBottom = 0;
	HistoryItem *_visibleTopItem = nullptr;
	int _visibleTopFromItem = 0;

	bool _scrollDateShown = false;
	Animation _scrollDateOpacity;
	SingleQueuedInvokation _scrollDateCheck;
	base::Timer _scrollDateHideTimer;
	HistoryItem *_scrollDateLastItem = nullptr;
	int _scrollDateLastItemTop = 0;
	ClickHandlerPtr _scrollDateLink;

	// Up - max, Down - min.
	uint64 _maxId = 0;
	uint64 _minId = 0;
	mtpRequestId _preloadUpRequestId = 0;
	mtpRequestId _preloadDownRequestId = 0;
	bool _upLoaded = false;
	bool _downLoaded = true;

	MouseAction _mouseAction = MouseAction::None;
	TextSelectType _mouseSelectType = TextSelectType::Letters;
	QPoint _dragStartPosition;
	QPoint _mousePosition;
	HistoryItem *_mouseActionItem = nullptr;
	HistoryCursorState _mouseCursorState = HistoryDefaultCursorState;
	uint16 _mouseTextSymbol = 0;
	bool _pressWasInactive = false;

	HistoryItem *_selectedItem = nullptr;
	TextSelection _selectedText;
	bool _wasSelectedText = false; // was some text selected in current drag action
	Qt::CursorShape _cursor = style::cur_default;

	// context menu
	Ui::PopupMenu *_menu = nullptr;

	QPoint _trippleClickPoint;
	base::Timer _trippleClickTimer;

	MTPDchannelAdminLogEventsFilter::Flags _filterFlags = 0;
	std::vector<gsl::not_null<UserData*>> _filterAdmins;

};

} // namespace AdminLog