/*
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 "boxes/create_ai_box.h"

#include "apiwrap.h"
#include "base/object_ptr.h"
#include "chat_helpers/compose/compose_show.h"
#include "data/data_file_origin.h"
#include "data/data_msg_id.h"
#include "iv/iv_cached_media.h"
#include "iv/iv_rich_page.h"
#include "iv/markdown/iv_markdown_article.h"
#include "iv/markdown/iv_markdown_common.h"
#include "iv/markdown/iv_markdown_prepare.h"
#include "lang/lang_keys.h"
#include "main/main_session.h"
#include "mtproto/mtproto_response.h"
#include "spellcheck/spellcheck_types.h"
#include "ui/boxes/choose_language_box.h"
#include "ui/chat/chat_style.h"
#include "ui/chat/chat_theme.h"
#include "ui/layers/generic_box.h"
#include "ui/painter.h"
#include "ui/rp_widget.h"
#include "ui/widgets/buttons.h"
#include "ui/widgets/checkbox.h"
#include "ui/widgets/fields/input_field.h"
#include "ui/widgets/labels.h"
#include "window/themes/window_theme.h"
#include "styles/style_boxes.h"
#include "styles/style_chat.h"
#include "styles/style_iv.h"
#include "styles/style_layers.h"

namespace Iv::Editor {
namespace {

[[nodiscard]] LanguageId DefaultAiTranslateTo(LanguageId offeredFrom) {
	const auto current = LanguageId{
		QLocale(Lang::LanguageIdOrDefault(Lang::Id())).language()
	};
	if (current && (current != offeredFrom)) {
		return current;
	}
	const auto english = LanguageId{ QLocale::English };
	if (english != offeredFrom) {
		return english;
	}
	return LanguageId{ QLocale::Spanish };
}

[[nodiscard]] TextWithEntities SelectorTitle(LanguageId id) {
	return tr::lng_ai_compose_to_language(
		tr::now,
		lt_language,
		tr::link(Ui::LanguageName(id)),
		tr::marked);
}

class PromptIsland final : public Ui::RpWidget {
public:
	PromptIsland(QWidget *parent);

	[[nodiscard]] not_null<Ui::InputField*> field() const;

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

	object_ptr<Ui::InputField> _field;

};

PromptIsland::PromptIsland(QWidget *parent)
: RpWidget(parent)
, _field(
	this,
	st::createAiPromptField,
	Ui::InputField::Mode::MultiLine,
	tr::lng_ai_compose_create_placeholder()) {
	_field->setSubmitSettings(Ui::InputField::SubmitSettings::None);
	_field->heightChanges() | rpl::on_next([=] {
		if (width() > 0) {
			resizeToWidth(width());
		}
	}, lifetime());
	resizeToWidth(st::boxWideWidth);
}

not_null<Ui::InputField*> PromptIsland::field() const {
	return _field.data();
}

void PromptIsland::paintEvent(QPaintEvent *e) {
	auto p = Painter(this);
	auto hq = PainterHighQualityEnabler(p);
	p.setPen(Qt::NoPen);
	p.setBrush(st::aiComposeCardBg);
	p.drawRoundedRect(
		rect(),
		st::aiComposeCardRadius,
		st::aiComposeCardRadius);
}

void PromptIsland::resizeEvent(QResizeEvent *e) {
	const auto &padding = st::aiComposeCardPadding;
	const auto inner = width() - padding.left() - padding.right();
	_field->resizeToWidth(inner);
	_field->moveToLeft(padding.left(), padding.top());
	const auto height = padding.top() + _field->height() + padding.bottom();
	if (this->height() != height) {
		resize(width(), height);
	}
}

class ResponseIsland final : public Ui::RpWidget {
public:
	ResponseIsland(
		QWidget *parent,
		not_null<Main::Session*> session,
		std::shared_ptr<const RichPage> page,
		LanguageId language,
		bool emojify,
		Fn<void()> chooseLanguage,
		Fn<void(bool)> emojifyChanged);

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

	void paintArticle(Painter &p, QRect clip);
	void requestArticleRepaint(QRect articleRect);

	[[nodiscard]] int controlRowHeight() const;
	[[nodiscard]] QRect articleRect() const;

	const not_null<Main::Session*> _session;
	const object_ptr<Ui::FlatLabel> _selector;
	const object_ptr<Ui::RpWidget> _arrows;
	const object_ptr<Ui::Checkbox> _emojify;
	std::unique_ptr<Ui::ChatTheme> _theme;
	std::unique_ptr<Ui::ChatStyle> _style;
	Iv::Markdown::MarkdownArticle _article;
	std::shared_ptr<Iv::Markdown::MediaRuntime> _mediaRuntime;
	int _articleHeight = 0;
	int _paletteVersion = -1;
	bool _hasArticle = false;

};

ResponseIsland::ResponseIsland(
	QWidget *parent,
	not_null<Main::Session*> session,
	std::shared_ptr<const RichPage> page,
	LanguageId language,
	bool emojify,
	Fn<void()> chooseLanguage,
	Fn<void(bool)> emojifyChanged)
: RpWidget(parent)
, _session(session)
, _selector(this, st::aiComposeCardTitle)
, _arrows(this)
, _emojify(
	this,
	tr::lng_ai_compose_emojify(tr::now),
	st::aiComposeEmojifyCheckbox,
	std::make_unique<Ui::RoundCheckView>(st::defaultCheck, emojify))
, _theme(Window::Theme::DefaultChatThemeOn(lifetime()))
, _style(std::make_unique<Ui::ChatStyle>(session->colorIndicesValue()))
, _article(st::messageMarkdown) {
	_style->apply(_theme.get());
	_paletteVersion = _style->paletteVersion();

	_selector->setMarkedText(SelectorTitle(language));
	_selector->setClickHandlerFilter([=](const auto &...) {
		if (chooseLanguage) {
			chooseLanguage();
		}
		return false;
	});

	const auto &icon = st::createAiSelectorArrowsIcon;
	_arrows->setAttribute(Qt::WA_TransparentForMouseEvents);
	_arrows->resize(icon.size());
	_arrows->paintRequest() | rpl::on_next([=] {
		auto p = QPainter(_arrows.data());
		st::createAiSelectorArrowsIcon.paint(p, 0, 0, _arrows->width());
	}, _arrows->lifetime());

	_emojify->checkedChanges() | rpl::on_next([=](bool checked) {
		if (emojifyChanged) {
			emojifyChanged(checked);
		}
	}, _emojify->lifetime());

	_article.setTextRepaintCallbacks(
		[=] { requestArticleRepaint(QRect()); },
		[=](QRect rect) { requestArticleRepaint(rect); });

	const auto richLimits = Iv::ResolveRichMessageLimits(session);
	_mediaRuntime = Iv::CreateMessageMediaRuntime(
		session,
		FullMsgId(),
		[](QString) {},
		[](QString) {},
		::Data::FileOrigin());
	auto prepared = Iv::Markdown::TryPrepareNativeInstantView({
		.richPage = page,
		.mediaRuntime = _mediaRuntime,
		.dimensionsOverride = Iv::Markdown::CaptureMarkdownPrepareDimensions(
			st::messageMarkdown),
		.tableRenderLimits
			= Iv::Markdown::PrepareTableRenderLimitsForRichMessage(richLimits),
	});
	if (prepared.supported()) {
		_article.setContent(std::move(prepared.content));
		_hasArticle = true;
	}
}

void ResponseIsland::requestArticleRepaint(QRect rect) {
	crl::on_main(this, [=] {
		if (rect.isEmpty()) {
			update();
		} else {
			update(rect.translated(articleRect().topLeft()));
		}
	});
}

QRect ResponseIsland::articleRect() const {
	const auto &padding = st::aiComposeCardPadding;
	const auto inner = std::max(width() - padding.left() - padding.right(), 0);
	const auto top = padding.top()
		+ controlRowHeight()
		+ st::aiComposeCardSectionSkip;
	return QRect(padding.left(), top, inner, _articleHeight);
}

void ResponseIsland::paintArticle(Painter &p, QRect clip) {
	if (!_hasArticle) {
		return;
	}
	if (_paletteVersion != _style->paletteVersion()) {
		_paletteVersion = _style->paletteVersion();
		_article.invalidatePaletteCache();
	}
	const auto content = articleRect();
	if (content.isEmpty()) {
		return;
	}
	const auto articleClip = content.intersected(clip).translated(
		-content.topLeft());
	if (articleClip.isEmpty()) {
		return;
	}
	auto context = Iv::Markdown::MarkdownArticlePaintContext(
		_theme->preparePaintContext(
			_style.get(),
			QRect(QPoint(), content.size()),
			QRect(QPoint(), content.size()),
			articleClip,
			false));
	const auto messageStyle = context.messageStyle();
	context.caches = {
		.pre = messageStyle->preCache.get(),
		.blockquote = context.quoteCache({}, 0),
		.colors = _style->highlightColors(),
		.st = &messageStyle->richPageStyle,
		.repaint = [=] { requestArticleRepaint(QRect()); },
		.repaintRect = [=](QRect rect) { requestArticleRepaint(rect); },
	};
	_article.setVisibleTopBottom(0, content.height());
	p.save();
	p.setClipRect(content.intersected(clip));
	p.translate(content.topLeft());
	_article.paint(p, context);
	p.restore();
}

int ResponseIsland::controlRowHeight() const {
	return std::max(_selector->height(), _emojify->height());
}

void ResponseIsland::paintEvent(QPaintEvent *e) {
	auto p = Painter(this);
	{
		auto hq = PainterHighQualityEnabler(p);
		p.setPen(Qt::NoPen);
		p.setBrush(st::aiComposeCardBg);
		p.drawRoundedRect(
			rect(),
			st::aiComposeCardRadius,
			st::aiComposeCardRadius);
	}
	paintArticle(p, e->rect());
}

void ResponseIsland::resizeEvent(QResizeEvent *e) {
	const auto &padding = st::aiComposeCardPadding;
	const auto inner = width() - padding.left() - padding.right();
	const auto rowHeight = controlRowHeight();

	_emojify->resizeToNaturalWidth(inner);
	_emojify->moveToRight(
		padding.right(),
		padding.top() + (rowHeight - _emojify->height()) / 2,
		width());

	const auto arrowsSkip = st::aiComposeCardControlSkip;
	const auto selectorWidth = std::max(
		inner
			- _emojify->width()
			- st::aiComposeCardControlSkip
			- _arrows->width()
			- arrowsSkip,
		0);
	_selector->resizeToWidth(selectorWidth);
	_selector->moveToLeft(
		padding.left(),
		padding.top() + (rowHeight - _selector->height()) / 2);
	_arrows->moveToLeft(
		padding.left() + _selector->textMaxWidth() + arrowsSkip,
		padding.top() + (rowHeight - _arrows->height()) / 2);

	auto y = padding.top() + rowHeight;
	if (_hasArticle && inner > 0) {
		y += st::aiComposeCardSectionSkip;
		_articleHeight = _article.resizeGetHeight(inner);
		y += _articleHeight;
	}
	y += padding.bottom();
	if (height() != y) {
		resize(width(), y);
	}
}

struct State {
	not_null<Main::Session*> session;
	Fn<void(std::shared_ptr<const RichPage>)> applyToPage;
	mtpRequestId requestId = 0;
	Ui::InputField *prompt = nullptr;
	LanguageId language;
	bool emojify = false;
	enum class Phase {
		Initial,
		Loading,
		HasResult,
	};
	Phase phase = Phase::Initial;
	std::shared_ptr<const RichPage> page;
	Ui::RpWidget *responseIsland = nullptr;
	Ui::RoundButton *reloadButton = nullptr;
	Fn<void()> generate;
	Fn<void()> rebuildButtons;
	Fn<void()> rebuildResponseIsland;
};

} // namespace

void CreateAiBox(not_null<Ui::GenericBox*> box, CreateAiBoxArgs &&args) {
	const auto state = box->lifetime().make_state<State>(State{
		.session = args.session,
		.applyToPage = std::move(args.applyToPage),
		.language = DefaultAiTranslateTo(LanguageId()),
	});

	box->setWidth(st::boxWideWidth);
	box->setTitle(tr::lng_ai_compose_create_title());
	box->addTopButton(st::aiComposeBoxClose, [=] {
		box->closeBox();
	});
	box->setStyle(st::aiComposeBox);

	const auto island = box->addRow(
		object_ptr<PromptIsland>(box),
		st::boxRowPadding);
	state->prompt = island->field();

	const auto chooseLanguage = [=] {
		box->uiShow()->showBox(Box([=](not_null<Ui::GenericBox*> chooser) {
			Ui::ChooseLanguageBox(
				chooser,
				tr::lng_languages(),
				[=](std::vector<LanguageId> ids) {
					if (ids.empty()) {
						return;
					}
					state->language = ids.front();
					state->generate();
				},
				{ state->language },
				false,
				nullptr);
		}));
	};

	state->rebuildResponseIsland = [=] {
		if (state->responseIsland) {
			delete state->responseIsland;
			state->responseIsland = nullptr;
		}
		if (!state->page) {
			return;
		}
		const auto content = box->verticalLayout();
		state->responseIsland = content->insert(
			1,
			object_ptr<ResponseIsland>(
				content,
				state->session,
				state->page,
				state->language,
				state->emojify,
				chooseLanguage,
				[=](bool checked) {
					state->emojify = checked;
					state->generate();
				}),
			style::margins(
				st::boxRowPadding.left(),
				st::aiComposeCardSectionSkip,
				st::boxRowPadding.right(),
				0));
	};

	state->rebuildButtons = [=] {
		if (state->reloadButton) {
			delete state->reloadButton;
			state->reloadButton = nullptr;
		}
		box->clearButtons();
		if (state->phase == State::Phase::HasResult) {
			box->setStyle(st::aiComposeBoxWithSend);
			const auto pill = box->addButton(
				tr::lng_ai_compose_add_to_page(),
				[=] {
					if (state->applyToPage) {
						state->applyToPage(state->page);
					}
				});
			pill->setFullRadius(true);

			const auto reload = Ui::CreateChild<Ui::RoundButton>(
				pill->parentWidget(),
				rpl::single(QString()),
				st::createAiReloadButton);
			reload->setFullRadius(true);
			reload->show();
			const auto icon = Ui::CreateChild<Ui::RpWidget>(reload);
			icon->setAttribute(Qt::WA_TransparentForMouseEvents);
			icon->resize(st::createAiReloadIcon.size());
			icon->paintRequest() | rpl::on_next([=] {
				auto p = QPainter(icon);
				st::createAiReloadIcon.paint(p, 0, 0, icon->width());
			}, icon->lifetime());
			icon->move(
				(reload->width() - icon->width()) / 2,
				(reload->height() - icon->height()) / 2);
			pill->geometryValue() | rpl::on_next([=](QRect geometry) {
				const auto size = st::createAiReloadButton.height;
				reload->moveToLeft(
					geometry.x()
						+ geometry.width()
						+ st::aiComposeSendButtonSkip,
					geometry.y() + (geometry.height() - size) / 2);
			}, reload->lifetime());
			reload->setClickedCallback([=] {
				state->generate();
			});
			state->reloadButton = reload;
		} else {
			box->setStyle(st::aiComposeBox);
			box->addButton(
				tr::lng_ai_compose_generate(),
				[=] { state->generate(); }
			)->setFullRadius(true);
		}
	};

	state->generate = [=] {
		const auto prompt = state->prompt->getLastText();
		if (prompt.trimmed().isEmpty()) {
			return;
		}
		if (state->requestId) {
			state->session->api().request(state->requestId).cancel();
			state->requestId = 0;
		}
		state->phase = State::Phase::Loading;
		state->rebuildButtons();

		using Flag = MTPmessages_composeRichMessageWithAI::Flag;
		auto flags = MTPmessages_composeRichMessageWithAI::Flags(0)
			| Flag::f_tone;
		if (state->emojify) {
			flags |= Flag::f_emojify;
		}
		const auto lang = state->language
			? state->language.twoLetterCode()
			: QString();
		if (!lang.isEmpty()) {
			flags |= Flag::f_translate_to_lang;
		}
		state->requestId = state->session->api().request(
			MTPmessages_ComposeRichMessageWithAI(
				MTP_flags(flags),
				MTPInputRichMessage(),
				lang.isEmpty() ? MTPstring() : MTP_string(lang),
				MTP_inputAiComposeToneSingleUse(MTP_string(prompt)))
		).done([=](const MTPmessages_ComposedRichMessageWithAI &result) {
			state->requestId = 0;
			state->page = Iv::ParseRichPage(
				state->session,
				result.data().vresult());
			state->phase = State::Phase::HasResult;
			state->rebuildResponseIsland();
			state->rebuildButtons();
		}).fail([=](const MTP::Error &error) {
			state->requestId = 0;
			state->phase = state->page
				? State::Phase::HasResult
				: State::Phase::Initial;
			state->rebuildButtons();
			if (MTP::IgnoreError(error)) {
				return;
			}
			box->showToast(error.type());
		}).handleFloodErrors().send();
	};

	state->rebuildButtons();
}

void ShowCreateAiBox(
		std::shared_ptr<ChatHelpers::Show> show,
		CreateAiBoxArgs &&args) {
	show->show(Box(CreateAiBox, std::move(args)));
}

} // namespace Iv::Editor