/*
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) 2014-2016 John Preston, https://desktop.telegram.org
*/
#pragma once

#include "localimageloader.h"
#include "ui/filedialog.h"
#include "ui/effects/rect_shadow.h"
#include "ui/widgets/tooltip.h"
#include "ui/widgets/input_fields.h"
#include "ui/widgets/scroll_area.h"
#include "history/history_common.h"
#include "history/field_autocomplete.h"
#include "window/section_widget.h"
#include "core/single_timer.h"

namespace InlineBots {
namespace Layout {
class ItemBase;
} // namespace Layout
class Result;
} // namespace InlineBots

namespace Ui {
class InnerDropdown;
class DropdownMenu;
class PlainShadow;
class PopupMenu;
class IconButton;
class HistoryDownButton;
class EmojiButton;
class FlatButton;
class LinkButton;
class RoundButton;
} // namespace Ui

class DragArea;
class EmojiPan;
class SilentToggle;
class SendFilesBox;

class HistoryWidget;
class HistoryInner : public TWidget, public Ui::AbstractTooltipShower, private base::Subscriber {
	Q_OBJECT

public:
	HistoryInner(HistoryWidget *historyWidget, Ui::ScrollArea *scroll, History *history);

	void messagesReceived(PeerData *peer, const QVector<MTPMessage> &messages);
	void messagesReceivedDown(PeerData *peer, const QVector<MTPMessage> &messages);

	void showContextMenu(QContextMenuEvent *e, bool showFromTouch = false);

	TextWithEntities getSelectedText() const;

	void dragActionStart(const QPoint &screenPos, Qt::MouseButton button = Qt::LeftButton);
	void dragActionUpdate(const QPoint &screenPos);
	void dragActionFinish(const QPoint &screenPos, Qt::MouseButton button = Qt::LeftButton);
	void dragActionCancel();

	void touchScrollUpdated(const QPoint &screenPos);
	QPoint mapMouseToItem(QPoint p, HistoryItem *item);

	void recountHeight();
	void updateSize();

	void repaintItem(const HistoryItem *item);

	bool canCopySelected() const;
	bool canDeleteSelected() const;

	void getSelectionState(int32 &selectedForForward, int32 &selectedForDelete) const;
	void clearSelectedItems(bool onlyTextSelection = false);
	void fillSelectedItems(SelectedItemSet &sel, bool forDelete = true);
	void selectItem(HistoryItem *item);

	void updateBotInfo(bool recount = true);

	bool wasSelectedText() const;
	void setFirstLoading(bool loading);

	// updates history->scrollTopItem/scrollTopOffset
	void visibleAreaUpdated(int top, int bottom);

	int historyHeight() const;
	int historyScrollTop() const;
	int migratedTop() const;
	int historyTop() const;
	int historyDrawTop() const;
	int itemTop(const HistoryItem *item) const; // -1 if should not be visible, -2 if bad history()

	void notifyIsBotChanged();
	void notifyMigrateUpdated();

	// When inline keyboard has moved because of the edition of its item we want
	// to move scroll position so that mouse points to the same button row.
	int moveScrollFollowingInlineKeyboard(const HistoryItem *item, int oldKeyboardTop, int newKeyboardTop);

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

	~HistoryInner();

protected:
	bool focusNextPrevChild(bool next) override;

	bool event(QEvent *e) override; // calls touchEvent when necessary
	void touchEvent(QTouchEvent *e);
	void paintEvent(QPaintEvent *e) override;
	void mouseMoveEvent(QMouseEvent *e) override;
	void mousePressEvent(QMouseEvent *e) override;
	void mouseReleaseEvent(QMouseEvent *e) override;
	void mouseDoubleClickEvent(QMouseEvent *e) override;
	void enterEvent(QEvent *e) override;
	void leaveEvent(QEvent *e) override;
	void resizeEvent(QResizeEvent *e) override;
	void keyPressEvent(QKeyEvent *e) override;

public slots:
	void onUpdateSelected();
	void onParentGeometryChanged();

	void copyContextUrl();
	void copyContextImage();
	void cancelContextDownload();
	void showContextInFolder();
	void saveContextGif();
	void copyContextText();
	void copySelectedText();

	void onMenuDestroy(QObject *obj);
	void onTouchSelect();
	void onTouchScrollTimer();
	void onDragExec();

private slots:
	void onScrollDateCheck();
	void onScrollDateHide();

private:
	void itemRemoved(HistoryItem *item);
	void savePhotoToFile(PhotoData *photo);
	void saveDocumentToFile(DocumentData *document);

	void touchResetSpeed();
	void touchUpdateSpeed();
	void touchDeaccelerate(int32 elapsed);

	void adjustCurrent(int32 y) const;
	void adjustCurrent(int32 y, History *history) const;
	HistoryItem *prevItem(HistoryItem *item);
	HistoryItem *nextItem(HistoryItem *item);
	void updateDragSelection(HistoryItem *dragSelFrom, HistoryItem *dragSelTo, bool dragSelecting, bool force = false);

	void setToClipboard(const TextWithEntities &forClipboard, QClipboard::Mode mode = QClipboard::Clipboard);

	void toggleScrollDateShown();
	void repaintScrollDateCallback();
	bool displayScrollDate() const;

	PeerData *_peer = nullptr;
	History *_migrated = nullptr;
	History *_history = nullptr;
	int _historyPaddingTop = 0;

	// with migrated history we perhaps do not need to display first _history message
	// (if last _migrated message and first _history message are both isGroupMigrate)
	// or at least we don't need to display first _history date (just skip it by height)
	int _historySkipHeight = 0;

	class BotAbout : public ClickHandlerHost {
	public:
		BotAbout(HistoryInner *parent, BotInfo *info) : info(info), _parent(parent) {
		}
		BotInfo *info = nullptr;
		int width = 0;
		int height = 0;
		QRect rect;

		// ClickHandlerHost interface
		void clickHandlerActiveChanged(const ClickHandlerPtr &p, bool active) override;
		void clickHandlerPressedChanged(const ClickHandlerPtr &p, bool pressed) override;

	private:
		HistoryInner *_parent;

	};
	std_::unique_ptr<BotAbout> _botAbout;

	HistoryWidget *_widget = nullptr;
	Ui::ScrollArea *_scroll = nullptr;
	mutable History *_curHistory = nullptr;
	mutable int _curBlock = 0;
	mutable int _curItem = 0;

	bool _firstLoading = false;

	style::cursor _cursor = style::cur_default;
	using SelectedItems = QMap<HistoryItem*, TextSelection>;
	SelectedItems _selected;
	void applyDragSelection();
	void applyDragSelection(SelectedItems *toItems) const;
	void addSelectionRange(SelectedItems *toItems, int32 fromblock, int32 fromitem, int32 toblock, int32 toitem, History *h) const;

	// Does any of the shown histories has this flag set.
	bool hasPendingResizedItems() const {
		return (_history && _history->hasPendingResizedItems()) || (_migrated && _migrated->hasPendingResizedItems());
	}

	enum DragAction {
		NoDrag        = 0x00,
		PrepareDrag   = 0x01,
		Dragging      = 0x02,
		PrepareSelect = 0x03,
		Selecting     = 0x04,
	};
	DragAction _dragAction = NoDrag;
	TextSelectType _dragSelType = TextSelectType::Letters;
	QPoint _dragStartPos, _dragPos;
	HistoryItem *_dragItem = nullptr;
	HistoryCursorState _dragCursorState = HistoryDefaultCursorState;
	uint16 _dragSymbol = 0;
	bool _dragWasInactive = false;

	QPoint _trippleClickPoint;
	QTimer _trippleClickTimer;

	ClickHandlerPtr _contextMenuLnk;

	HistoryItem *_dragSelFrom = nullptr;
	HistoryItem *_dragSelTo = nullptr;
	bool _dragSelecting = false;
	bool _wasSelectedText = false; // was some text selected in current drag action

	// scroll by touch support (at least Windows Surface tablets)
	bool _touchScroll = false;
	bool _touchSelect = false;
	bool _touchInProgress = false;
	QPoint _touchStart, _touchPrevPos, _touchPos;
	QTimer _touchSelectTimer;

	Ui::TouchScrollState _touchScrollState = Ui::TouchScrollState::Manual;
	bool _touchPrevPosValid = false;
	bool _touchWaitingAcceleration = false;
	QPoint _touchSpeed;
	TimeMs _touchSpeedTime = 0;
	TimeMs _touchAccelerationTime = 0;
	TimeMs _touchTime = 0;
	QTimer _touchScrollTimer;

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

	// save visible area coords for painting / pressing userpics
	int _visibleAreaTop = 0;
	int _visibleAreaBottom = 0;

	bool _scrollDateShown = false;
	Animation _scrollDateOpacity;
	SingleDelayedCall _scrollDateCheck = { this, "onScrollDateCheck" };
	SingleTimer _scrollDateHideTimer;
	HistoryItem *_scrollDateLastItem = nullptr;
	int _scrollDateLastItemTop = 0;

	enum class EnumItemsDirection {
		TopToBottom,
		BottomToTop,
	};
	// this function finds all history items that are displayed and calls template method
	// for each found message (in given direction) in the passed history with passed top offset
	//
	// method has "bool (*Method)(HistoryItem *item, int itemtop, int itembottom)" signature
	// if it returns false the enumeration stops immidiately
	template <bool TopToBottom, typename Method>
	void enumerateItemsInHistory(History *history, int historytop, Method method);

	template <EnumItemsDirection direction, typename Method>
	void enumerateItems(Method method) {
		constexpr auto TopToBottom = (direction == EnumItemsDirection::TopToBottom);
		if (TopToBottom && _migrated) {
			enumerateItemsInHistory<TopToBottom>(_migrated, migratedTop(), method);
		}
		enumerateItemsInHistory<TopToBottom>(_history, historyTop(), method);
		if (!TopToBottom && _migrated) {
			enumerateItemsInHistory<TopToBottom>(_migrated, migratedTop(), method);
		}
	}

	// this function finds all userpics on the left that are displayed and calls template method
	// for each found userpic (from the top to the bottom) using enumerateItems() method
	//
	// method has "bool (*Method)(HistoryMessage *message, int userpicTop)" signature
	// if it returns false the enumeration stops immidiately
	template <typename Method>
	void enumerateUserpics(Method method);

	// this function finds all date elements that are displayed and calls template method
	// for each found date element (from the bottom to the top) using enumerateItems() method
	//
	// method has "bool (*Method)(HistoryItem *item, int itemtop, int dateTop)" signature
	// if it returns false the enumeration stops immidiately
	template <typename Method>
	void enumerateDates(Method method);

};

class MessageField : public Ui::FlatTextarea {
	Q_OBJECT

public:
	MessageField(HistoryWidget *history, const style::FlatTextarea &st, const QString &ph = QString(), const QString &val = QString());
	void dropEvent(QDropEvent *e);
	bool canInsertFromMimeData(const QMimeData *source) const;
	void insertFromMimeData(const QMimeData *source);

	void focusInEvent(QFocusEvent *e);

	bool hasSendText() const;

public slots:
	void onEmojiInsert(EmojiPtr emoji);

signals:
	void focused();

private:
	HistoryWidget *history;

};

class HistoryWidget;
class ReportSpamPanel : public TWidget {
	Q_OBJECT

public:
	ReportSpamPanel(HistoryWidget *parent);

	void setReported(bool reported, PeerData *onPeer);

signals:
	void hideClicked();
	void reportClicked();
	void clearClicked();

protected:
	void resizeEvent(QResizeEvent *e) override;
	void paintEvent(QPaintEvent *e) override;

private:
	ChildWidget<Ui::FlatButton> _report;
	ChildWidget<Ui::FlatButton> _hide;
	ChildWidget<Ui::LinkButton> _clear;

};

class BotKeyboard : public TWidget, public Ui::AbstractTooltipShower, public ClickHandlerHost {
	Q_OBJECT

public:
	BotKeyboard(QWidget *parent);

	bool moderateKeyActivate(int index);

	// With force=true the markup is updated even if it is
	// already shown for the passed history item.
	bool updateMarkup(HistoryItem *last, bool force = false);
	bool hasMarkup() const;
	bool forceReply() const;

	void step_selected(TimeMs ms, bool timer);
	void resizeToWidth(int newWidth, int maxOuterHeight) {
		_maxOuterHeight = maxOuterHeight;
		return TWidget::resizeToWidth(newWidth);
	}

	bool maximizeSize() const;
	bool singleUse() const;

	FullMsgId forMsgId() const {
		return _wasForMsgId;
	}

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

	// ClickHandlerHost interface
	void clickHandlerActiveChanged(const ClickHandlerPtr &p, bool active) override;
	void clickHandlerPressedChanged(const ClickHandlerPtr &p, bool pressed) override;

protected:
	int resizeGetHeight(int newWidth) override;

	void paintEvent(QPaintEvent *e) override;
	void mousePressEvent(QMouseEvent *e) override;
	void mouseMoveEvent(QMouseEvent *e) override;
	void mouseReleaseEvent(QMouseEvent *e) override;
	void enterEvent(QEvent *e) override;
	void leaveEvent(QEvent *e) override;

private:
	void updateSelected();

	void updateStyle(int newWidth);
	void clearSelection();

	FullMsgId _wasForMsgId;
	int _height = 0;
	int _maxOuterHeight = 0;
	bool _maximizeSize = false;
	bool _singleUse = false;
	bool _forceReply = false;

	QPoint _lastMousePos;
	std_::unique_ptr<ReplyKeyboard> _impl;

	class Style : public ReplyKeyboard::Style {
	public:
		Style(BotKeyboard *parent, const style::BotKeyboardButton &st) : ReplyKeyboard::Style(st), _parent(parent) {
		}

		int buttonRadius() const override;

		void startPaint(Painter &p) const override;
		style::font textFont() const override;
		void repaint(const HistoryItem *item) const override;

	protected:
		void paintButtonBg(Painter &p, const QRect &rect, float64 howMuchOver) const override;
		void paintButtonIcon(Painter &p, const QRect &rect, int outerWidth, HistoryMessageReplyMarkup::Button::Type type) const override;
		void paintButtonLoading(Painter &p, const QRect &rect) const override;
		int minButtonWidth(HistoryMessageReplyMarkup::Button::Type type) const override;

	private:
		BotKeyboard *_parent;

	};
	const style::BotKeyboardButton *_st = nullptr;

};

class HistoryHider : public TWidget, private base::Subscriber {
	Q_OBJECT

public:
	HistoryHider(MainWidget *parent, bool forwardSelected); // forward messages
	HistoryHider(MainWidget *parent, UserData *sharedContact); // share contact
	HistoryHider(MainWidget *parent); // send path from command line argument
	HistoryHider(MainWidget *parent, const QString &url, const QString &text); // share url
	HistoryHider(MainWidget *parent, const QString &botAndQuery); // inline switch button handler

	bool withConfirm() const;

	bool offerPeer(PeerId peer);
	QString offeredText() const;
	QString botAndQuery() const {
		return _botAndQuery;
	}

	bool wasOffered() const;

	void forwardDone();

	~HistoryHider();

protected:
	void paintEvent(QPaintEvent *e) override;
	void keyPressEvent(QKeyEvent *e) override;
	void mousePressEvent(QMouseEvent *e) override;
	void resizeEvent(QResizeEvent *e) override;

public slots:
	void startHide();
	void forward();

signals:
	void forwarded();

private:
	void animationCallback();
	void init();
	MainWidget *parent();

	UserData *_sharedContact = nullptr;
	bool _forwardSelected = false;
	bool _sendPath = false;

	QString _shareUrl, _shareText;
	QString _botAndQuery;

	ChildWidget<Ui::RoundButton> _send;
	ChildWidget<Ui::RoundButton> _cancel;
	PeerData *_offered = nullptr;

	Animation _a_opacity;

	QRect _box;
	bool _hiding = false;

	mtpRequestId _forwardRequest = 0;

	int _chooseWidth = 0;

	Text _toText;
	int32 _toTextWidth = 0;
	QPixmap _cacheForAnim;

	Ui::RectShadow _shadow;

};

EntitiesInText entitiesFromTextTags(const TextWithTags::Tags &tags);
TextWithTags::Tags textTagsFromEntities(const EntitiesInText &entities);

class HistoryWidget : public TWidget, public RPCSender, private base::Subscriber {
	Q_OBJECT

public:
	HistoryWidget(QWidget *parent);

	void start();

	void messagesReceived(PeerData *peer, const MTPmessages_Messages &messages, mtpRequestId requestId);
	void historyLoaded();

	void windowShown();
	bool doWeReadServerHistory() const;

	void leaveToChildEvent(QEvent *e, QWidget *child) override;
	void dragEnterEvent(QDragEnterEvent *e) override;
	void dragLeaveEvent(QDragLeaveEvent *e) override;
    void dropEvent(QDropEvent *e) override;

	void updateTopBarSelection();

	bool paintTopBar(Painter &p, int decreaseWidth, TimeMs ms);
	QRect getMembersShowAreaGeometry() const;
	void setMembersShowAreaActive(bool active);
	void topBarClick();

	void loadMessages();
	void loadMessagesDown();
	void firstLoadMessages();
	void delayedShowAt(MsgId showAtMsgId);
	void peerMessagesUpdated(PeerId peer);
	void peerMessagesUpdated();

	void newUnreadMsg(History *history, HistoryItem *item);
	void historyToDown(History *history);
	void historyWasRead(ReadServerHistoryChecks checks);
	void historyCleared(History *history);
	void unreadCountChanged(History *history);

	QRect historyRect() const;

	void updateSendAction(History *history, SendAction::Type type, int32 progress = 0);
	void cancelSendAction(History *history, SendAction::Type type);

	void updateRecentStickers();
	void stickersInstalled(uint64 setId);
	void sendActionDone(const MTPBool &result, mtpRequestId req);

	void destroyData();

	void updateFieldPlaceholder();
	void updateStickersByEmoji();

	bool confirmSendingFiles(const QList<QUrl> &files, CompressConfirm compressed = CompressConfirm::Auto, const QString *addedComment = nullptr);
	bool confirmSendingFiles(const QStringList &files, CompressConfirm compressed = CompressConfirm::Auto, const QString *addedComment = nullptr);
	bool confirmSendingFiles(const QImage &image, const QByteArray &content, CompressConfirm compressed = CompressConfirm::Auto, const QString &insertTextOnCancel = QString());
	bool confirmSendingFiles(const QMimeData *data, CompressConfirm compressed = CompressConfirm::Auto, const QString &insertTextOnCancel = QString());
	bool confirmShareContact(const QString &phone, const QString &fname, const QString &lname, const QString *addedComment = nullptr);

	void uploadFile(const QByteArray &fileContent, SendMediaType type);
	void uploadFiles(const QStringList &files, SendMediaType type);

	void sendFileConfirmed(const FileLoadResultPtr &file);

	void updateControlsVisibility();
	void updateControlsGeometry();
	void updateOnlineDisplay();
	void updateOnlineDisplayTimer();

	void onShareContact(const PeerId &peer, UserData *contact);

	void shareContact(const PeerId &peer, const QString &phone, const QString &fname, const QString &lname, MsgId replyTo, int32 userId = 0);

	History *history() const;
	PeerData *peer() const;
	void setMsgId(MsgId showAtMsgId);
	MsgId msgId() const;

	bool hasTopBarShadow() const {
		return peer() != nullptr;
	}
	void showAnimated(Window::SlideDirection direction, const Window::SectionSlideParams &params);
	void finishAnimation();

	void doneShow();

	QPoint clampMousePosition(QPoint point);

	void checkSelectingScroll(QPoint point);
	void noSelectingScroll();

	bool touchScroll(const QPoint &delta);

	uint64 animActiveTimeStart(const HistoryItem *msg) const;
	void stopAnimActive();

	void fillSelectedItems(SelectedItemSet &sel, bool forDelete = true);
	void itemEdited(HistoryItem *item);

	void updateScrollColors();

	MsgId replyToId() const;
	void messageDataReceived(ChannelData *channel, MsgId msgId);
	bool lastForceReplyReplied(const FullMsgId &replyTo = FullMsgId(NoChannel, -1)) const;
	bool cancelReply(bool lastKeyboardUsed = false);
	void cancelEdit();
	void updateForwarding(bool force = false);
	void cancelForwarding(); // called by MainWidget

	void clearReplyReturns();
	void pushReplyReturn(HistoryItem *item);
	QList<MsgId> replyReturns();
	void setReplyReturns(PeerId peer, const QList<MsgId> &replyReturns);
	void calcNextReplyReturn();

	void updatePreview();
	void previewCancel();

	void step_recording(float64 ms, bool timer);
	void stopRecording(bool send);

	void onListEscapePressed();
	void onListEnterPressed();

	void sendBotCommand(PeerData *peer, UserData *bot, const QString &cmd, MsgId replyTo);
	void hideSingleUseKeyboard(PeerData *peer, MsgId replyTo);
	bool insertBotCommand(const QString &cmd, bool specialGif);

	bool eventFilter(QObject *obj, QEvent *e) override;

	// With force=true the markup is updated even if it is
	// already shown for the passed history item.
	void updateBotKeyboard(History *h = nullptr, bool force = false);

	DragState getDragState(const QMimeData *d);

	void fastShowAtEnd(History *h);
	void applyDraft(bool parseLinks = true);
	void showHistory(const PeerId &peer, MsgId showAtMsgId, bool reload = false);
	void clearDelayedShowAt();
	void clearAllLoadRequests();
	void saveFieldToHistoryLocalDraft();

	void applyCloudDraft(History *history);

	void contactsReceived();
	void updateHistoryDownPosition();
	void updateHistoryDownVisibility();

	void updateAfterDrag();
	void updateFieldSubmitSettings();

	void setInnerFocus();
	bool canSendMessages(PeerData *peer) const;

	void updateNotifySettings();

	void saveGif(DocumentData *doc);

	bool contentOverlapped(const QRect &globalRect);

	void grabStart() override {
		_inGrab = true;
		updateControlsGeometry();
	}
	void grapWithoutTopBarShadow();
	void grabFinish() override;

	bool isItemVisible(HistoryItem *item);

	void app_sendBotCallback(const HistoryMessageReplyMarkup::Button *button, const HistoryItem *msg, int row, int col);

	void ui_repaintHistoryItem(const HistoryItem *item);
	void ui_repaintInlineItem(const InlineBots::Layout::ItemBase *gif);
	bool ui_isInlineItemVisible(const InlineBots::Layout::ItemBase *layout);
	bool ui_isInlineItemBeingChosen();
	PeerData *ui_getPeerForMouseAction();

	void notify_historyItemLayoutChanged(const HistoryItem *item);
	void notify_inlineItemLayoutChanged(const InlineBots::Layout::ItemBase *layout);
	void notify_botCommandsChanged(UserData *user);
	void notify_inlineBotRequesting(bool requesting);
	void notify_replyMarkupUpdated(const HistoryItem *item);
	void notify_inlineKeyboardMoved(const HistoryItem *item, int oldKeyboardTop, int newKeyboardTop);
	bool notify_switchInlineBotButtonReceived(const QString &query, UserData *samePeerBot, MsgId samePeerReplyTo);
	void notify_userIsBotChanged(UserData *user);
	void notify_migrateUpdated(PeerData *peer);
	void notify_clipStopperHidden(ClipStopperType type);
	void notify_handlePendingHistoryUpdate();

	bool cmd_search();
	bool cmd_next_chat();
	bool cmd_previous_chat();

	~HistoryWidget();

protected:
	void resizeEvent(QResizeEvent *e) override;
	void keyPressEvent(QKeyEvent *e) override;
	void mousePressEvent(QMouseEvent *e) override;
	void paintEvent(QPaintEvent *e) override;
	void leaveEvent(QEvent *e) override;
	void mouseReleaseEvent(QMouseEvent *e) override;
	void mouseMoveEvent(QMouseEvent *e) override;
	void contextMenuEvent(QContextMenuEvent *e) override;

signals:
	void cancelled();
	void historyShown(History *history, MsgId atMsgId);

public slots:
	void onCancel();
	void onReplyToMessage();
	void onEditMessage();
	void onPinMessage();
	void onUnpinMessage();
	void onUnpinMessageSure();
	void onPinnedHide();
	void onCopyPostLink();
	void onFieldBarCancel();

	void onCancelSendAction();

	void onStickerPackInfo();

	void onPreviewParse();
	void onPreviewCheck();
	void onPreviewTimeout();

	void peerUpdated(PeerData *data);
	void onFullPeerUpdated(PeerData *data);

	void onPhotoUploaded(const FullMsgId &msgId, bool silent, const MTPInputFile &file);
	void onDocumentUploaded(const FullMsgId &msgId, bool silent, const MTPInputFile &file);
	void onThumbDocumentUploaded(const FullMsgId &msgId, bool silent, const MTPInputFile &file, const MTPInputFile &thumb);

	void onPhotoProgress(const FullMsgId &msgId);
	void onDocumentProgress(const FullMsgId &msgId);

	void onPhotoFailed(const FullMsgId &msgId);
	void onDocumentFailed(const FullMsgId &msgId);

	void onReportSpamClicked();
	void onReportSpamSure();
	void onReportSpamHide();
	void onReportSpamClear();

	void onScroll();
	void onHistoryToEnd();
	void onSend(bool ctrlShiftEnter = false, MsgId replyTo = -1);

	void onUnblock();
	void onBotStart();
	void onJoinChannel();
	void onMuteUnmute();
	void onBroadcastSilentChange();

	void onKbToggle(bool manual = true);
	void onCmdStart();

	void activate();
	void onStickersUpdated();
	void onTextChange();

	void onFieldTabbed();
	bool onStickerSend(DocumentData *sticker);
	void onPhotoSend(PhotoData *photo);
	void onInlineResultSend(InlineBots::Result *result, UserData *bot);

	void onWindowVisibleChanged();

	void deleteMessage();
	void forwardMessage();
	void selectMessage();

	void onForwardHere(); // instead of a reply

	void onFieldFocused();
	void onFieldResize();
	void onCheckFieldAutocomplete();
	void onScrollTimer();

	void onForwardSelected();
	void onDeleteSelected();
	void onDeleteSelectedSure();
	void onDeleteContextSure();
	void onClearSelected();

	void onAnimActiveStep();

	void onDraftSaveDelayed();
	void onDraftSave(bool delayed = false);
	void onCloudDraftSave();

	void updateStickers();

	void onRecordError();
	void onRecordDone(QByteArray result, VoiceWaveform waveform, qint32 samples);
	void onRecordUpdate(quint16 level, qint32 samples);

	void onUpdateHistoryItems();

	// checks if we are too close to the top or to the bottom
	// in the scroll area and preloads history if needed
	void preloadHistoryIfNeeded();

private slots:
	void onHashtagOrBotCommandInsert(QString str, FieldAutocomplete::ChooseMethod method);
	void onMentionInsert(UserData *user);
	void onInlineBotCancel();
	void onMembersDropdownShow();

	void onModerateKeyActivate(int index, bool *outHandled);

	void updateField();

private:
	void animationCallback();
	void recordActiveCallback();
	void chooseAttach();
	void historyDownAnimationFinish();
	void notifyFileQueryUpdated(const FileDialog::QueryUpdate &update);
	struct SendingFilesLists {
		QList<QUrl> nonLocalUrls;
		QStringList directories;
		QStringList emptyFiles;
		QStringList tooLargeFiles;
		QStringList filesToSend;
		bool allFilesForCompress = true;
	};
	SendingFilesLists getSendingFilesLists(const QList<QUrl> &files);
	SendingFilesLists getSendingFilesLists(const QStringList &files);
	void getSendingLocalFileInfo(SendingFilesLists &result, const QString &filepath);
	bool confirmSendingFiles(const SendingFilesLists &lists, CompressConfirm compressed = CompressConfirm::Auto, const QString *addedComment = nullptr);
	template <typename Callback>
	bool validateSendingFiles(const SendingFilesLists &lists, Callback callback);
	template <typename SendCallback>
	bool showSendFilesBox(SendFilesBox *box, const QString &insertTextOnCancel, const QString *addedComment, SendCallback callback);
	CompressConfirm imageCompressConfirm(const QImage &image, CompressConfirm compressed, bool animated = false);

	// If an empty filepath is found we upload (possible) "image" with (possible) "content".
	void uploadFilesAfterConfirmation(const QStringList &files, const QImage &image, const QByteArray &content, SendMediaType type, QString caption);

	void itemRemoved(HistoryItem *item);

	// Updates position of controls around the message field,
	// like send button, emoji button and others.
	void moveFieldControls();
	void updateFieldSize();

	bool historyHasNotFreezedUnreadBar(History *history) const;
	bool canWriteMessage() const;

	void clearInlineBot();
	void inlineBotChanged();

	// Look in the _field for the inline bot and query string.
	void updateInlineBotQuery();

	// Request to show results in the emoji panel.
	void applyInlineBotQuery(UserData *bot, const QString &query);

	void cancelReplyAfterMediaSend(bool lastKeyboardUsed);

	void hideSelectorControlsAnimated();
	int countMembersDropdownHeightMax() const;

	MsgId _replyToId = 0;
	Text _replyToName;
	int _replyToNameVersion = 0;
	void updateReplyToName();

	MsgId _editMsgId = 0;

	HistoryItem *_replyEditMsg = nullptr;
	Text _replyEditMsgText;
	mutable SingleTimer _updateEditTimeLeftDisplay;

	ChildWidget<Ui::IconButton> _fieldBarCancel;
	void updateReplyEditTexts(bool force = false);

	struct PinnedBar {
		PinnedBar(MsgId msgId, HistoryWidget *parent);
		~PinnedBar();

		MsgId msgId = 0;
		HistoryItem *msg = nullptr;
		Text text;
		ChildWidget<Ui::IconButton> cancel;
		ChildWidget<Ui::PlainShadow> shadow;
	};
	std_::unique_ptr<PinnedBar> _pinnedBar;
	void updatePinnedBar(bool force = false);
	bool pinnedMsgVisibilityUpdated();
	void destroyPinnedBar();
	void unpinDone(const MTPUpdates &updates);

	bool sendExistingDocument(DocumentData *doc, const QString &caption);
	void sendExistingPhoto(PhotoData *photo, const QString &caption);

	void drawField(Painter &p, const QRect &rect);
	void paintEditHeader(Painter &p, const QRect &rect, int left, int top) const;
	void drawRecordButton(Painter &p, float64 recordActive, TimeMs ms);
	void drawRecording(Painter &p, float64 recordActive);
	void drawPinnedBar(Painter &p);

	void updateMouseTracking();

	// destroys _history and _migrated unread bars
	void destroyUnreadBar();

	mtpRequestId _saveEditMsgRequestId = 0;
	void saveEditMsg();
	void saveEditMsgDone(History *history, const MTPUpdates &updates, mtpRequestId req);
	bool saveEditMsgFail(History *history, const RPCError &error, mtpRequestId req);

	static const mtpRequestId ReportSpamRequestNeeded = -1;
	DBIPeerReportSpamStatus _reportSpamStatus = dbiprsUnknown;
	mtpRequestId _reportSpamSettingRequestId = ReportSpamRequestNeeded;
	void updateReportSpamStatus();
	void requestReportSpamSetting();
	void reportSpamSettingDone(const MTPPeerSettings &result, mtpRequestId req);
	bool reportSpamSettingFail(const RPCError &error, mtpRequestId req);

	QString _previewLinks;
	WebPageData *_previewData = nullptr;
	typedef QMap<QString, WebPageId> PreviewCache;
	PreviewCache _previewCache;
	mtpRequestId _previewRequest = 0;
	Text _previewTitle;
	Text _previewDescription;
	SingleTimer _previewTimer;
	bool _previewCancelled = false;
	void gotPreview(QString links, const MTPMessageMedia &media, mtpRequestId req);

	bool _replyForwardPressed = false;

	HistoryItem *_replyReturn = nullptr;
	QList<MsgId> _replyReturns;

	bool messagesFailed(const RPCError &error, mtpRequestId requestId);
	void addMessagesToFront(PeerData *peer, const QVector<MTPMessage> &messages);
	void addMessagesToBack(PeerData *peer, const QVector<MTPMessage> &messages);

	struct BotCallbackInfo {
		UserData *bot;
		FullMsgId msgId;
		int row, col;
		bool game;
	};
	void botCallbackDone(BotCallbackInfo info, const MTPmessages_BotCallbackAnswer &answer, mtpRequestId req);
	bool botCallbackFail(BotCallbackInfo info, const RPCError &error, mtpRequestId req);

	enum ScrollChangeType {
		ScrollChangeNone,

		// When we toggle a pinned message.
		ScrollChangeAdd,

		// When loading a history part while scrolling down.
		ScrollChangeNoJumpToBottom,
	};
	struct ScrollChange {
		ScrollChangeType type;
		int value;
	};
	void updateListSize(bool initial = false, bool loadedDown = false, const ScrollChange &change = { ScrollChangeNone, 0 });

	// Does any of the shown histories has this flag set.
	bool hasPendingResizedItems() const {
		return (_history && _history->hasPendingResizedItems()) || (_migrated && _migrated->hasPendingResizedItems());
	}

	// Counts scrollTop for placing the scroll right at the unread
	// messages bar, choosing from _history and _migrated unreadBar.
	int unreadBarTop() const;

	void saveGifDone(DocumentData *doc, const MTPBool &result);

	void reportSpamDone(PeerData *peer, const MTPBool &result, mtpRequestId request);
	bool reportSpamFail(const RPCError &error, mtpRequestId request);

	void unblockDone(PeerData *peer, const MTPBool &result, mtpRequestId req);
	bool unblockFail(const RPCError &error, mtpRequestId req);
	void blockDone(PeerData *peer, const MTPBool &result);

	void joinDone(const MTPUpdates &result, mtpRequestId req);
	bool joinFail(const RPCError &error, mtpRequestId req);

	void countHistoryShowFrom();

	mtpRequestId _stickersUpdateRequest = 0;
	void stickersGot(const MTPmessages_AllStickers &stickers);
	bool stickersFailed(const RPCError &error);

	mtpRequestId _recentStickersUpdateRequest = 0;
	void recentStickersGot(const MTPmessages_RecentStickers &stickers);
	bool recentStickersFailed(const RPCError &error);

	mtpRequestId _featuredStickersUpdateRequest = 0;
	void featuredStickersGot(const MTPmessages_FeaturedStickers &stickers);
	bool featuredStickersFailed(const RPCError &error);

	mtpRequestId _savedGifsUpdateRequest = 0;
	void savedGifsGot(const MTPmessages_SavedGifs &gifs);
	bool savedGifsFailed(const RPCError &error);

	enum class TextUpdateEvent {
		SaveDraft  = 0x01,
		SendTyping = 0x02,
	};
	Q_DECLARE_FLAGS(TextUpdateEvents, TextUpdateEvent);
	Q_DECLARE_FRIEND_OPERATORS_FOR_FLAGS(TextUpdateEvents);

	void writeDrafts(Data::Draft **localDraft, Data::Draft **editDraft);
	void writeDrafts(History *history);
	void setFieldText(const TextWithTags &textWithTags, TextUpdateEvents events = 0, Ui::FlatTextarea::UndoHistoryAction undoHistoryAction = Ui::FlatTextarea::ClearUndoHistory);
	void clearFieldText(TextUpdateEvents events = 0, Ui::FlatTextarea::UndoHistoryAction undoHistoryAction = Ui::FlatTextarea::ClearUndoHistory) {
		setFieldText(TextWithTags(), events, undoHistoryAction);
	}

	void updateDragAreas();

	// when scroll position or scroll area size changed this method
	// updates the boundings of the visible area in HistoryInner
	void visibleAreaUpdated();

	bool readyToForward() const;
	bool hasSilentToggle() const;

	PeerData *_peer = nullptr;

	// cache current _peer in _clearPeer when showing clear history box
	PeerData *_clearPeer = nullptr;

	ChannelId _channel = NoChannel;
	bool _canSendMessages = false;
	MsgId _showAtMsgId = ShowAtUnreadMsgId;

	mtpRequestId _firstLoadRequest = 0;
	mtpRequestId _preloadRequest = 0;
	mtpRequestId _preloadDownRequest = 0;

	MsgId _delayedShowAtMsgId = -1; // wtf?
	mtpRequestId _delayedShowAtRequest = 0;

	MsgId _activeAnimMsgId = 0;

	ChildWidget<Ui::ScrollArea> _scroll;
	HistoryInner *_list = nullptr;
	History *_migrated = nullptr;
	History *_history = nullptr;
	bool _histInited = false; // initial updateListSize() called
	int _addToScroll = 0;

	int _lastScroll = 0;// gifs optimization
	TimeMs _lastScrolled = 0;
	QTimer _updateHistoryItems;

	Animation _historyDownShown;
	bool _historyDownIsShown = false;
	ChildWidget<Ui::HistoryDownButton> _historyDown;

	ChildWidget<FieldAutocomplete> _fieldAutocomplete;

	UserData *_inlineBot = nullptr;
	QString _inlineBotUsername;
	mtpRequestId _inlineBotResolveRequestId = 0;
	std_::unique_ptr<Ui::IconButton> _inlineBotCancel;
	void inlineBotResolveDone(const MTPcontacts_ResolvedPeer &result);
	bool inlineBotResolveFail(QString name, const RPCError &error);

	bool isBotStart() const;
	bool isBlocked() const;
	bool isJoinChannel() const;
	bool isMuteUnmute() const;
	bool updateCmdStartShown();

	ChildWidget<ReportSpamPanel> _reportSpamPanel;

	ChildWidget<Ui::IconButton> _send;
	ChildWidget<Ui::FlatButton> _unblock;
	ChildWidget<Ui::FlatButton> _botStart;
	ChildWidget<Ui::FlatButton> _joinChannel;
	ChildWidget<Ui::FlatButton> _muteUnmute;
	mtpRequestId _unblockRequest = 0;
	mtpRequestId _reportSpamRequest = 0;
	ChildWidget<Ui::IconButton> _attachToggle;
	ChildWidget<Ui::EmojiButton> _attachEmoji;
	ChildWidget<Ui::IconButton> _botKeyboardShow;
	ChildWidget<Ui::IconButton> _botKeyboardHide;
	ChildWidget<Ui::IconButton> _botCommandStart;
	ChildWidget<SilentToggle> _silent;
	bool _cmdStartShown = false;
	ChildWidget<MessageField> _field;
	bool _recording = false;
	bool _inRecord = false;
	bool _inField = false;
	bool _inReplyEdit = false;
	bool _inPinnedMsg = false;
	bool _inClickable = false;
	int _recordingSamples = 0;
	Animation _a_recordActive;
	std_::unique_ptr<Ui::RippleAnimation> _recordRipple;
	int _recordCancelWidth;

	// This can animate for a very long time (like in music playing),
	// so it should be a BasicAnimation, not an Animation.
	BasicAnimation _a_recording;
	anim::value a_recordingLevel;

	FileDialog::QueryId _attachFilesQueryId = 0;

	bool kbWasHidden() const;

	bool _kbShown = false;
	HistoryItem *_kbReplyTo = nullptr;
	ChildWidget<Ui::ScrollArea> _kbScroll;
	ChildWidget<BotKeyboard> _keyboard;

	ChildWidget<Ui::InnerDropdown> _membersDropdown = { nullptr };
	QTimer _membersDropdownShowTimer;

	ChildWidget<EmojiPan> _emojiPan;
	DragState _attachDrag = DragStateNone;
	ChildWidget<DragArea> _attachDragDocument, _attachDragPhoto;

	int32 _selCount; // < 0 - text selected, focus list, not _field

	TaskQueue _fileLoader;
	TextUpdateEvents _textUpdateEvents = (TextUpdateEvent::SaveDraft | TextUpdateEvent::SendTyping);

	int64 _serviceImageCacheSize = 0;
	QString _confirmSource;

	QString _titlePeerText;
	bool _titlePeerTextOnline = false;
	int _titlePeerTextWidth = 0;

	Animation _a_show;
	Window::SlideDirection _showDirection;
	QPixmap _cacheUnder, _cacheOver;

	QTimer _scrollTimer;
	int32 _scrollDelta = 0;

	QTimer _animActiveTimer;
	float64 _animActiveStart = 0;

	QMap<QPair<History*, SendAction::Type>, mtpRequestId> _sendActionRequests;
	QTimer _sendActionStopTimer;

	TimeMs _saveDraftStart = 0;
	bool _saveDraftText = false;
	QTimer _saveDraftTimer, _saveCloudDraftTimer;

	ChildWidget<Ui::PlainShadow> _topShadow;
	bool _inGrab = false;

};

Q_DECLARE_OPERATORS_FOR_FLAGS(HistoryWidget::TextUpdateEvents)