/*
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 "storage/storage_media_prepare.h"

#include "editor/photo_editor_common.h"
#include "platform/platform_file_utilities.h"
#include "lang/lang_keys.h"
#include "storage/localimageloader.h"
#include "core/mime_type.h"
#include "ui/image/image_prepare.h"
#include "ui/chat/attach/attach_prepare.h"
#include "core/crash_reports.h"

#include <QtCore/QSemaphore>
#include <QtCore/QMimeData>

namespace Storage {
namespace {

using Ui::PreparedFileInformation;
using Ui::PreparedFile;
using Ui::PreparedList;

using Image = PreparedFileInformation::Image;

bool ValidPhotoForAlbum(
		const Image &image,
		const QString &mime) {
	Expects(!image.data.isNull());

	if (image.animated
		|| (!mime.isEmpty() && !mime.startsWith(u"image/"))) {
		return false;
	}
	const auto width = image.data.width();
	const auto height = image.data.height();
	return Ui::ValidateThumbDimensions(width, height);
}

bool ValidVideoForAlbum(const PreparedFileInformation::Video &video) {
	const auto width = video.thumbnail.width();
	const auto height = video.thumbnail.height();
	return Ui::ValidateThumbDimensions(width, height);
}

QSize PrepareShownDimensions(const QImage &preview, int sideLimit) {
	const auto result = preview.size();
	return (result.width() > sideLimit || result.height() > sideLimit)
		? result.scaled(sideLimit, sideLimit, Qt::KeepAspectRatio)
		: result;
}

void PrepareDetailsInParallel(PreparedList &result, int previewWidth) {
	Expects(result.files.size() <= Ui::MaxAlbumItems());

	if (result.files.empty()) {
		return;
	}
	const auto sideLimit = PhotoSideLimit(); // Get on main thread.
	QSemaphore semaphore;
	for (auto &file : result.files) {
		crl::async([=, &semaphore, &file] {
			PrepareDetails(file, previewWidth, sideLimit);
			semaphore.release();
		});
	}
	semaphore.acquire(result.files.size());
}

} // namespace

bool ValidatePhotoEditorMediaDragData(not_null<const QMimeData*> data) {
	const auto urls = Core::ReadMimeUrls(data);
	if (urls.size() > 1) {
		return false;
	} else if (data->hasImage()) {
		return true;
	}

	if (!urls.isEmpty()) {
		const auto url = urls.front();
		if (url.isLocalFile()) {
			using namespace Core;
			const auto file = Platform::File::UrlToLocal(url);
			const auto info = QFileInfo(file);
			return FileIsImage(file, MimeTypeForFile(info).name())
				&& QImageReader(file).canRead();
		}
	}

	return false;
}

bool ValidateEditMediaDragData(
		not_null<const QMimeData*> data,
		Ui::AlbumType albumType) {
	const auto urls = Core::ReadMimeUrls(data);
	if (urls.size() > 1) {
		return false;
	} else if (data->hasImage()) {
		return (albumType != Ui::AlbumType::Music);
	}

	if (albumType == Ui::AlbumType::PhotoVideo && !urls.isEmpty()) {
		const auto url = urls.front();
		if (url.isLocalFile()) {
			using namespace Core;
			const auto info = QFileInfo(Platform::File::UrlToLocal(url));
			return IsMimeAcceptedForPhotoVideoAlbum(MimeTypeForFile(info).name());
		}
	}

	return true;
}

MimeDataState ComputeMimeDataState(const QMimeData *data) {
	if (!data || data->hasFormat(u"application/x-td-forward"_q)) {
		return MimeDataState::None;
	}

	if (data->hasImage()) {
		return MimeDataState::Image;
	}

	const auto urls = Core::ReadMimeUrls(data);
	if (urls.isEmpty()) {
		return MimeDataState::None;
	}

	auto allAreSmallImages = true;
	for (const auto &url : urls) {
		if (!url.isLocalFile()) {
			return MimeDataState::None;
		}
		const auto file = Platform::File::UrlToLocal(url);

		const auto info = QFileInfo(file);
		if (info.isDir()) {
			return MimeDataState::None;
		}

		using namespace Core;
		const auto filesize = info.size();
		if (filesize > kFileSizePremiumLimit) {
			return MimeDataState::None;
		//} else if (filesize > kFileSizeLimit) {
		//	return MimeDataState::PremiumFile;
		} else if (allAreSmallImages) {
			if (filesize > Images::kReadBytesLimit) {
				allAreSmallImages = false;
			} else {
				const auto mime = MimeTypeForFile(info).name();
				if (mime == u"image/gif"_q
					|| !FileIsImage(file, mime)
					|| !QImageReader(file).canRead()) {
					allAreSmallImages = false;
				}
			}
		}
	}
	return allAreSmallImages
		? MimeDataState::PhotoFiles
		: MimeDataState::Files;
}

PreparedList PrepareMediaList(
		const QList<QUrl> &files,
		int previewWidth,
		bool premium) {
	auto locals = QStringList();
	locals.reserve(files.size());
	for (const auto &url : files) {
		if (!url.isLocalFile()) {
			return {
				PreparedList::Error::NonLocalUrl,
				url.toDisplayString()
			};
		}
		locals.push_back(Platform::File::UrlToLocal(url));
	}
	return PrepareMediaList(locals, previewWidth, premium);
}

PreparedList PrepareMediaList(
		const QStringList &files,
		int previewWidth,
		bool premium) {
	auto result = PreparedList();
	result.files.reserve(files.size());
	for (const auto &file : files) {
		const auto fileinfo = QFileInfo(file);
		const auto filesize = fileinfo.size();
		if (fileinfo.isDir()) {
			return {
				PreparedList::Error::Directory,
				file
			};
		} else if (filesize <= 0) {
			return {
				PreparedList::Error::EmptyFile,
				file
			};
		} else if (filesize > kFileSizePremiumLimit
			|| (filesize > kFileSizeLimit && !premium)) {
			auto errorResult = PreparedList(
				PreparedList::Error::TooLargeFile,
				QString());
			errorResult.files.emplace_back(file);
			errorResult.files.back().size = filesize;
			return errorResult;
		}
		if (result.files.size() < Ui::MaxAlbumItems()) {
			result.files.emplace_back(file);
			result.files.back().size = filesize;
		} else {
			result.filesToProcess.emplace_back(file);
			result.files.back().size = filesize;
		}
	}
	PrepareDetailsInParallel(result, previewWidth);
	return result;
}

PreparedList PrepareMediaFromImage(
		QImage &&image,
		QByteArray &&content,
		int previewWidth) {
	Expects(!image.isNull());

	auto result = PreparedList();
	auto file = PreparedFile(QString());
	file.content = content;
	if (file.content.isEmpty()) {
		file.information = std::make_unique<PreparedFileInformation>();
		const auto animated = false;
		FileLoadTask::FillImageInformation(
			std::move(image),
			animated,
			file.information);
	}
	result.files.push_back(std::move(file));
	PrepareDetailsInParallel(result, previewWidth);
	return result;
}

std::optional<PreparedList> PreparedFileFromFilesDialog(
		FileDialog::OpenResult &&result,
		Fn<bool(const Ui::PreparedList&)> checkResult,
		Fn<void(tr::phrase<>)> errorCallback,
		int previewWidth,
		bool premium) {
	if (result.paths.isEmpty() && result.remoteContent.isEmpty()) {
		return std::nullopt;
	}

	auto list = result.remoteContent.isEmpty()
		? PrepareMediaList(result.paths, previewWidth, premium)
		: PrepareMediaFromImage(
			QImage(),
			std::move(result.remoteContent),
			previewWidth);
	if (list.error != PreparedList::Error::None) {
		errorCallback(tr::lng_send_media_invalid_files);
		return std::nullopt;
	} else if (!checkResult(list)) {
		return std::nullopt;
	} else {
		return list;
	}
}

void PrepareDetails(PreparedFile &file, int previewWidth, int sideLimit) {
	if (!file.path.isEmpty()) {
		file.information = FileLoadTask::ReadMediaInformation(
			file.path,
			QByteArray(),
			Core::MimeTypeForFile(QFileInfo(file.path)).name());
	} else if (!file.content.isEmpty()) {
		file.information = FileLoadTask::ReadMediaInformation(
			QString(),
			file.content,
			Core::MimeTypeForData(file.content).name());
	} else {
		Assert(file.information != nullptr);
	}

	using Video = PreparedFileInformation::Video;
	using Song = PreparedFileInformation::Song;
	if (const auto image = std::get_if<Image>(
			&file.information->media)) {
		Assert(!image->data.isNull());
		if (ValidPhotoForAlbum(*image, file.information->filemime)) {
			UpdateImageDetails(file, previewWidth, sideLimit);
			file.type = PreparedFile::Type::Photo;
		} else {
			file.originalDimensions = image->data.size();
			if (image->animated) {
				file.type = PreparedFile::Type::None;
			}
		}
	} else if (const auto video = std::get_if<Video>(
			&file.information->media)) {
		if (ValidVideoForAlbum(*video)) {
			auto blurred = Images::Blur(
				Images::Opaque(base::duplicate(video->thumbnail)));
			file.originalDimensions = video->thumbnail.size();
			file.shownDimensions = PrepareShownDimensions(
				video->thumbnail,
				sideLimit);
			file.preview = std::move(blurred).scaledToWidth(
				previewWidth * style::DevicePixelRatio(),
				Qt::SmoothTransformation);
			Assert(!file.preview.isNull());
			file.preview.setDevicePixelRatio(style::DevicePixelRatio());
			file.type = PreparedFile::Type::Video;
		}
	} else if (const auto song = std::get_if<Song>(&file.information->media)) {
		file.type = PreparedFile::Type::Music;
	}
}

void UpdateImageDetails(
		PreparedFile &file,
		int previewWidth,
		int sideLimit) {
	const auto image = std::get_if<Image>(&file.information->media);
	if (!image) {
		return;
	}
	Assert(!image->data.isNull());
	auto preview = image->modifications
		? Editor::ImageModified(image->data, image->modifications)
		: image->data;
	Assert(!preview.isNull());
	file.originalDimensions = preview.size();
	file.shownDimensions = PrepareShownDimensions(preview, sideLimit);
	const auto toWidth = std::min(
		previewWidth,
		style::ConvertScale(preview.width())
	) * style::DevicePixelRatio();
	auto scaled = preview.scaledToWidth(
		toWidth,
		Qt::SmoothTransformation);
	if (scaled.isNull()) {
		CrashReports::SetAnnotation("Info", QString("%1x%2:%3*%4->%5;%6x%7"
		).arg(preview.width()).arg(preview.height()
		).arg(previewWidth).arg(style::DevicePixelRatio()
		).arg(toWidth
		).arg(scaled.width()).arg(scaled.height()));
		Unexpected("Scaled is null.");
	}
	Assert(!scaled.isNull());
	file.preview = Images::Opaque(std::move(scaled));
	Assert(!file.preview.isNull());
	file.preview.setDevicePixelRatio(style::DevicePixelRatio());
}

bool ApplyModifications(PreparedList &list) {
	auto applied = false;
	const auto apply = [&](PreparedFile &file, QSize strictSize = {}) {
		const auto image = std::get_if<Image>(&file.information->media);
		const auto guard = gsl::finally([&] {
			if (!image || strictSize.isEmpty()) {
				return;
			}
			applied = true;
			file.path = QString();
			file.content = QByteArray();
			image->data = image->data.scaled(
				strictSize,
				Qt::IgnoreAspectRatio,
				Qt::SmoothTransformation);
		});
		if (!image || !image->modifications) {
			return;
		}
		applied = true;
		file.path = QString();
		file.content = QByteArray();
		image->data = Editor::ImageModified(
			std::move(image->data),
			image->modifications);
	};
	for (auto &file : list.files) {
		apply(file);
		if (const auto cover = file.videoCover.get()) {
			const auto video = file.information
				? std::get_if<Ui::PreparedFileInformation::Video>(
					&file.information->media)
				: nullptr;
			apply(*cover, video ? video->thumbnail.size() : QSize());
		}
	}
	return applied;
}

} // namespace Storage

