add remote cheats launcher

src/launcher/include/cheatFile.h

@@ -0,0 +1,26 @@
+#ifndef CHEAT_FILE_H
+#define CHEAT_FILE_H
+
+#include <QByteArray>
+#include <QJsonDocument>
+#include <QList>
+#include <QString>
+
+namespace Cheats {
+
+[[nodiscard]] bool    IsSupportedTitleId(const QString& title_id);
+[[nodiscard]] QString PlanPath(const QString& title_id);
+
+// Local files retain their existing defaults; remote imports receive additional validation.
+[[nodiscard]] QString       ParseDocument(const QByteArray& data, QJsonDocument* document);
+[[nodiscard]] QString       ValidateImport(const QJsonDocument& document, const QString& title_id,
+                                           const QString& version, const QString& process);
+[[nodiscard]] QJsonDocument WithSelection(const QJsonDocument& document,
+                                          const QList<bool>&   enabled);
+// Refuse to replace a file changed since it was loaded; empty data also permits creation.
+[[nodiscard]] QString SaveDocument(const QString& path, const QJsonDocument& document,
+                                   const QByteArray& expected_data);
+
+} // namespace Cheats
+
+#endif // CHEAT_FILE_H

src/launcher/include/cheatRepository.h

@@ -0,0 +1,66 @@
+#ifndef CHEAT_REPOSITORY_H
+#define CHEAT_REPOSITORY_H
+
+#include <QByteArray>
+#include <QList>
+#include <QNetworkAccessManager>
+#include <QObject>
+#include <QPointer>
+#include <QString>
+#include <QStringList>
+#include <QUrl>
+
+#include <functional>
+
+class QNetworkReply;
+
+namespace Cheats {
+
+struct RemoteFile {
+	QString name;
+	QString title;
+	QString version;
+	QString format;
+
+	[[nodiscard]] bool IsSupported() const;
+	[[nodiscard]] QUrl Url() const;
+};
+
+struct CatalogResult {
+	QList<RemoteFile> files;
+	QString           error;
+};
+
+[[nodiscard]] CatalogResult ParseIndex(const QByteArray& data, const QString& format,
+                                       const QString& title_id);
+
+class CheatRepository final: public QObject {
+	Q_OBJECT
+
+public:
+	explicit CheatRepository(QObject* parent = nullptr);
+	void Load(const QString& title_id);
+	void Fetch(const RemoteFile& file);
+	void CancelFetch();
+
+signals:
+	void CatalogLoaded(QList<Cheats::RemoteFile> files, QString error);
+	void FileLoaded(QByteArray data, QString error);
+
+private:
+	QNetworkReply* Request(const QUrl& url, qint64 limit,
+	                       std::function<void(QByteArray, QString)> complete);
+
+	QNetworkAccessManager   m_network;
+	QList<QNetworkReply*>   m_catalog_replies;
+	QPointer<QNetworkReply> m_file_reply;
+	QList<RemoteFile>       m_files;
+	QStringList             m_errors;
+	int                     m_catalog_generation = 0;
+	int                     m_fetch_generation   = 0;
+	int                     m_pending            = 0;
+};
+
+} // namespace Cheats
+
+#endif // CHEAT_REPOSITORY_H

src/launcher/include/patchesDialog.h

@@ -1,30 +1,51 @@
 #ifndef PATCHES_DIALOG_H
 #define PATCHES_DIALOG_H
 
+#include "cheatRepository.h"
+
+#include <QByteArray>
 #include <QDialog>
+#include <QJsonDocument>
 #include <QString>
 
 class Configuration;
 class QLabel;
 class QListWidget;
 class QPushButton;
+class QTabWidget;
+class QTreeWidget;
 
 class PatchesDialog final: public QDialog {
 public:
 	explicit PatchesDialog(const Configuration& game, QWidget* parent = nullptr);
 	~PatchesDialog() override = default;
 
-	[[nodiscard]] static bool    IsSupportedTitleId(const QString& title_id);
-	[[nodiscard]] static QString PatchPlanPath(const QString& title_id);
-
 private:
 	void Load();
 	void Save();
+	void LoadRemote();
+	void PreviewRemote();
+	void ImportRemote();
 
-	QString      m_title_id;
+	QString                   m_title_id;
-	QListWidget* m_patches = nullptr;
+	QString                   m_version;
-	QLabel*      m_status  = nullptr;
+	QString                   m_process;
-	QPushButton* m_apply   = nullptr;
+	QByteArray                m_local_data;
+	QJsonDocument             m_local_document;
+	QJsonDocument             m_remote_document;
+	bool                      m_local_readable = false;
+	Cheats::CheatRepository*  m_repository     = nullptr;
+	QList<Cheats::RemoteFile> m_remote_files;
+	QTabWidget*               m_tabs           = nullptr;
+	QTreeWidget*              m_files          = nullptr;
+	QListWidget*              m_preview        = nullptr;
+	QLabel*                   m_remote_status  = nullptr;
+	QLabel*                   m_preview_status = nullptr;
+	QPushButton*              m_refresh        = nullptr;
+	QPushButton*              m_import         = nullptr;
+	QListWidget*              m_patches        = nullptr;
+	QLabel*                   m_status         = nullptr;
+	QPushButton*              m_apply          = nullptr;
 };
 
 #endif // PATCHES_DIALOG_H

src/launcher/src/cheatFile.cpp

@@ -0,0 +1,180 @@
+#include "cheatFile.h"
+
+#include <QCoreApplication>
+#include <QDir>
+#include <QFile>
+#include <QFileInfo>
+#include <QJsonArray>
+#include <QJsonObject>
+#include <QRegularExpression>
+#include <QSaveFile>
+
+namespace Cheats {
+
+namespace {
+
+QString Tr(const char* text) {
+	return QCoreApplication::translate("Cheats", text);
+}
+
+QString ValidateDocument(const QJsonDocument& document) {
+	if (!document.isObject()) {
+		return Tr("Invalid cheat JSON.");
+	}
+	const auto mods = document.object().value(QStringLiteral("mods"));
+	if (!mods.isArray()) {
+		return Tr("Cheat JSON has no \"mods\" array.");
+	}
+	for (const auto& value: mods.toArray()) {
+		const auto mod     = value.toObject();
+		const auto name    = mod.value(QStringLiteral("name"));
+		const auto enabled = mod.value(QStringLiteral("enabled"));
+		if (!value.isObject() || !name.isString() || name.toString().isEmpty() ||
+		    (!enabled.isUndefined() && !enabled.isBool())) {
+			return Tr("Invalid cheat entry.");
+		}
+	}
+	return {};
+}
+
+} // namespace
+
+bool IsSupportedTitleId(const QString& title_id) {
+	static const QRegularExpression pattern(QStringLiteral("\\APPSA[0-9]{5}\\z"));
+	return pattern.match(title_id.trimmed().toUpper()).hasMatch();
+}
+
+QString PlanPath(const QString& title_id) {
+	if (!IsSupportedTitleId(title_id)) {
+		return {};
+	}
+	return QDir(QCoreApplication::applicationDirPath())
+	    .filePath(QStringLiteral("_Patches/%1.json").arg(title_id.trimmed().toUpper()));
+}
+
+QString ParseDocument(const QByteArray& data, QJsonDocument* document) {
+	const auto parsed = QJsonDocument::fromJson(data);
+	const auto error  = ValidateDocument(parsed);
+	*document         = error.isEmpty() ? parsed : QJsonDocument();
+	return error;
+}
+
+QString ValidateImport(const QJsonDocument& document, const QString& title_id,
+                       const QString& version, const QString& process) {
+	const auto parse_error = ValidateDocument(document);
+	if (!parse_error.isEmpty()) {
+		return parse_error;
+	}
+	const auto root = document.object();
+	if (!IsSupportedTitleId(title_id) ||
+	    root.value(QStringLiteral("id"))
+	            .toString()
+	            .compare(title_id.trimmed(), Qt::CaseInsensitive) != 0) {
+		return Tr("The cheat file does not match this game's title ID.");
+	}
+	if (version.isEmpty() || root.value(QStringLiteral("version")).toString() != version) {
+		return Tr("The cheat file does not match this game's version (%1).").arg(version);
+	}
+	if (process.isEmpty() ||
+	    root.value(QStringLiteral("process")).toString().compare(process, Qt::CaseInsensitive) !=
+	        0) {
+		return Tr("The cheat file does not match this game's executable (%1).").arg(process);
+	}
+	static const QRegularExpression offset_pattern(
+	    QStringLiteral("\\A(?:0[xX])?[0-9a-fA-F]{1,16}\\z"));
+	static const QRegularExpression bytes_pattern(QStringLiteral("\\A(?:[0-9a-fA-F]{2})+\\z"));
+	const auto                      mods = root.value(QStringLiteral("mods")).toArray();
+	if (mods.isEmpty()) {
+		return Tr("The cheat file contains no cheats.");
+	}
+	if (root.contains(QStringLiteral("master"))) {
+		return Tr("This JSON uses master codes, which are not supported yet.");
+	}
+	for (const auto& value: mods) {
+		const auto mod    = value.toObject();
+		const auto memory = mod.value(QStringLiteral("memory"));
+		if (mod.contains(QStringLiteral("module_name"))) {
+			return Tr("This JSON uses module-specific cheats, which are not supported yet.");
+		}
+		if (!memory.isArray() || memory.toArray().isEmpty()) {
+			return Tr("Unsupported memory entries in cheat \"%1\".")
+			    .arg(mod.value(QStringLiteral("name")).toString());
+		}
+		for (const auto& entry: memory.toArray()) {
+			const auto write    = entry.toObject();
+			const auto offset   = write.value(QStringLiteral("offset")).toString();
+			const auto off      = write.value(QStringLiteral("off")).toString();
+			const auto on       = write.value(QStringLiteral("on")).toString();
+			const auto absolute = write.value(QStringLiteral("absolute"));
+			const auto expected = write.value(QStringLiteral("expected"));
+			if ((!absolute.isUndefined() && (!absolute.isBool() || absolute.toBool())) ||
+			    (!expected.isUndefined() &&
+			     (!expected.isString() ||
+			      expected.toString().compare(off, Qt::CaseInsensitive) != 0)) ||
+			    write.contains(QStringLiteral("section")) ||
+			    write.contains(QStringLiteral("sectionName")) ||
+			    write.contains(QStringLiteral("sectionProtection")) ||
+			    write.contains(QStringLiteral("logicalOffset")) ||
+			    write.contains(QStringLiteral("sectionOffset"))) {
+				return Tr("This JSON uses memory addressing features that are not supported yet.");
+			}
+			if (!entry.isObject() || !offset_pattern.match(offset).hasMatch() ||
+			    !bytes_pattern.match(off).hasMatch() || !bytes_pattern.match(on).hasMatch() ||
+			    off.size() != on.size()) {
+				return Tr("Unsupported memory entries in cheat \"%1\".")
+				    .arg(mod.value(QStringLiteral("name")).toString());
+			}
+		}
+	}
+	return {};
+}
+
+QJsonDocument WithSelection(const QJsonDocument& document, const QList<bool>& enabled) {
+	auto root = document.object();
+	auto mods = root.value(QStringLiteral("mods")).toArray();
+	if (mods.size() != enabled.size()) {
+		return {};
+	}
+	for (qsizetype index = 0; index < mods.size(); ++index) {
+		auto mod = mods[index].toObject();
+		mod.insert(QStringLiteral("enabled"), enabled[index]);
+		mods[index] = mod;
+	}
+	root.insert(QStringLiteral("mods"), mods);
+	return QJsonDocument(root);
+}
+
+QString SaveDocument(const QString& path, const QJsonDocument& document,
+                     const QByteArray& expected_data) {
+	if (path.isEmpty() || !document.isObject()) {
+		return Tr("Invalid cheat file.");
+	}
+	QFile input(path);
+	if (input.exists()) {
+		if (!input.open(QIODevice::ReadOnly)) {
+			return Tr("Could not read cheat file: %1").arg(input.errorString());
+		}
+		const auto current = input.readAll();
+		if (input.error() != QFile::NoError) {
+			return Tr("Could not read cheat file: %1").arg(input.errorString());
+		}
+		if (current != expected_data) {
+			return Tr("Cheat file changed; reload the dialog.");
+		}
+	} else if (!expected_data.isEmpty()) {
+		return Tr("Cheat file changed; reload the dialog.");
+	}
+	input.close();
+	if (!QDir().mkpath(QFileInfo(path).absolutePath())) {
+		return Tr("Could not create the local cheats directory.");
+	}
+	QSaveFile  output(path);
+	const auto data = document.toJson();
+	if (!output.open(QIODevice::WriteOnly) || output.write(data) != data.size() ||
+	    !output.commit()) {
+		return Tr("Could not save cheat file: %1").arg(output.errorString());
+	}
+	return {};
+}
+
+} // namespace Cheats

src/launcher/src/cheatRepository.cpp

@@ -0,0 +1,200 @@
+#include "cheatRepository.h"
+
+#include <QNetworkReply>
+#include <QNetworkRequest>
+#include <QRegularExpression>
+#include <QSet>
+#include <QTimer>
+
+#include <algorithm>
+#include <utility>
+
+namespace Cheats {
+
+namespace {
+
+constexpr qint64 kIndexLimit = 2 * 1024 * 1024;
+constexpr qint64 kFileLimit  = 8 * 1024 * 1024;
+
+const QString kBaseUrl = QStringLiteral(
+    "https://raw.githubusercontent.com/TeeKay87/HEN-Cheats-Collection/master/cheats/");
+
+bool IsFormat(const QString& format) {
+	return format == QStringLiteral("json") || format == QStringLiteral("mc4") ||
+	       format == QStringLiteral("shn");
+}
+
+QRegularExpressionMatch MatchName(const QString& name) {
+	static const QRegularExpression pattern(QStringLiteral(
+	    "\\A([A-Z]{4}[0-9]{5})_([0-9]+(?:\\.[0-9]+)+)_[A-Za-z0-9_.-]+\\.(json|mc4|shn)\\z"));
+	return pattern.match(name);
+}
+
+} // namespace
+
+bool RemoteFile::IsSupported() const {
+	return format == QStringLiteral("json") && !Url().isEmpty();
+}
+
+QUrl RemoteFile::Url() const {
+	const auto match = MatchName(name);
+	if (!IsFormat(format) || !match.hasMatch() || match.captured(3) != format) {
+		return {};
+	}
+	return QUrl(kBaseUrl + format + QLatin1Char('/') + name);
+}
+
+CatalogResult ParseIndex(const QByteArray& data, const QString& format, const QString& title_id) {
+	CatalogResult result;
+	if (!IsFormat(format) || data.isEmpty() || data.size() > kIndexLimit) {
+		result.error = CheatRepository::tr("Invalid cheat index.");
+		return result;
+	}
+
+	const auto    id = title_id.trimmed().toUpper();
+	QSet<QString> seen;
+	int           invalid = 0;
+	auto          text    = QString::fromUtf8(data);
+	if (text.startsWith(QChar(0xfeff))) {
+		text.remove(0, 1);
+	}
+	for (const auto& line: text.split(QLatin1Char('\n'))) {
+		const auto trimmed = line.trimmed();
+		if (trimmed.isEmpty()) {
+			continue;
+		}
+		const auto separator = trimmed.indexOf(QLatin1Char('='));
+		const auto name      = trimmed.left(separator);
+		const auto match     = MatchName(name);
+		if (separator < 0 || !match.hasMatch() || match.captured(3) != format) {
+			invalid++;
+			continue;
+		}
+		if (match.captured(1) != id || seen.contains(name)) {
+			continue;
+		}
+		seen.insert(name);
+		result.files.append(
+		    {name, trimmed.mid(separator + 1).trimmed(), match.captured(2), format});
+	}
+	if (invalid != 0) {
+		result.error = CheatRepository::tr("Skipped %1 invalid cheat index entries.").arg(invalid);
+	}
+	return result;
+}
+
+CheatRepository::CheatRepository(QObject* parent): QObject(parent), m_network(this) {}
+
+QNetworkReply* CheatRepository::Request(const QUrl& url, qint64 limit,
+                                        std::function<void(QByteArray, QString)> complete) {
+	QNetworkRequest request(url);
+	request.setAttribute(QNetworkRequest::RedirectPolicyAttribute,
+	                     QNetworkRequest::SameOriginRedirectPolicy);
+	request.setRawHeader("User-Agent", "Kyty-Launcher");
+	request.setTransferTimeout(15000);
+	auto* reply = m_network.get(request);
+	reply->setReadBufferSize(limit + 1);
+	connect(reply, &QNetworkReply::readyRead, this, [reply, limit]() {
+		if (reply->bytesAvailable() > limit) {
+			reply->setProperty("too_large", true);
+			reply->abort();
+		}
+	});
+	QTimer::singleShot(30000, reply, [reply]() {
+		if (!reply->isFinished()) {
+			reply->setProperty("timed_out", true);
+			reply->abort();
+		}
+	});
+	connect(reply, &QNetworkReply::finished, this,
+	        [this, reply, limit, complete = std::move(complete)]() {
+		        QString error;
+		        if (reply->property("too_large").toBool() || reply->bytesAvailable() > limit) {
+			        error = tr("Cheat download exceeds the size limit.");
+		        } else if (reply->property("timed_out").toBool()) {
+			        error = tr("Cheat download timed out.");
+		        } else if (reply->error() != QNetworkReply::NoError) {
+			        error = reply->errorString();
+		        } else if (reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt() !=
+		                   200) {
+			        error = tr("Unexpected response from the cheat repository.");
+		        }
+		        const auto data = error.isEmpty() ? reply->readAll() : QByteArray();
+		        m_catalog_replies.removeAll(reply);
+		        if (m_file_reply == reply) {
+			        m_file_reply.clear();
+		        }
+		        reply->deleteLater();
+		        complete(data, error);
+	        });
+	return reply;
+}
+
+void CheatRepository::Load(const QString& title_id) {
+	const auto generation = ++m_catalog_generation;
+	for (auto* reply: std::exchange(m_catalog_replies, {})) {
+		reply->abort();
+	}
+	CancelFetch();
+	m_files.clear();
+	m_errors.clear();
+	m_pending = 3;
+	for (const auto& format:
+	     {QStringLiteral("json"), QStringLiteral("mc4"), QStringLiteral("shn")}) {
+		auto* reply =
+		    Request(QUrl(kBaseUrl + format + QStringLiteral(".txt")), kIndexLimit,
+		            [this, generation, format, title_id](const QByteArray& data, QString error) {
+			            if (generation != m_catalog_generation) {
+				            return;
+			            }
+			            if (error.isEmpty()) {
+				            auto result = ParseIndex(data, format, title_id);
+				            m_files.append(result.files);
+				            error = result.error;
+			            }
+			            if (!error.isEmpty()) {
+				            m_errors.append(format.toUpper() + QStringLiteral(": ") + error);
+			            }
+			            if (--m_pending == 0) {
+				            std::sort(m_files.begin(), m_files.end(),
+				                      [](const RemoteFile& left, const RemoteFile& right) {
+					                      if (left.version != right.version) {
+						                      return left.version > right.version;
+					                      }
+					                      if (left.format != right.format) {
+						                      return left.format < right.format;
+					                      }
+					                      return left.name < right.name;
+				                      });
+				            emit CatalogLoaded(m_files, m_errors.join(QLatin1Char('\n')));
+			            }
+		            });
+		m_catalog_replies.append(reply);
+	}
+}
+
+void CheatRepository::Fetch(const RemoteFile& file) {
+	CancelFetch();
+	if (!file.IsSupported()) {
+		emit FileLoaded({}, tr("Only JSON cheat files are supported."));
+		return;
+	}
+	const auto generation = m_fetch_generation;
+	m_file_reply = Request(file.Url(), kFileLimit,
+	                       [this, generation](const QByteArray& data, const QString& error) {
+		                       if (generation == m_fetch_generation) {
+			                       emit FileLoaded(data, error);
+		                       }
+	                       });
+}
+
+void CheatRepository::CancelFetch() {
+	m_fetch_generation++;
+	if (m_file_reply != nullptr) {
+		auto* reply = m_file_reply.data();
+		m_file_reply.clear();
+		reply->abort();
+	}
+}
+
+} // namespace Cheats

src/launcher/src/configurationListWidget.cpp

@@ -1,5 +1,6 @@
 #include "configurationListWidget.h"
 
+#include "cheatFile.h"
 #include "common/archive.h"
 #include "compatibilityDatabase.h"
 #include "configuration.h"
@@ -1015,7 +1016,7 @@ void ConfigurationListWidget::show_context_menu(const QPoint& pos) {
 		        }
 	        });
 	action_patches->setVisible(item != nullptr &&
-	                           PatchesDialog::IsSupportedTitleId(item->GetInfo().title_id));
+	                           Cheats::IsSupportedTitleId(item->GetInfo().title_id));
 	QAction* action_remove_save_data =
 	    menu.addAction(style()->standardIcon(QStyle::SP_DialogDiscardButton),
 	                   tr("Remove save data..."), this, SLOT(remove_save_data()));

src/launcher/src/mainDialog.cpp

@@ -1,11 +1,11 @@
 #include "mainDialog.h"
 
+#include "cheatFile.h"
 #include "configuration.h"
 #include "configurationItem.h"
 #include "configurationListWidget.h"
 #include "controllerLightbar.h"
 #include "gameContent.h"
-#include "patchesDialog.h"
 #include "updateChecker.h"
 
 #include <QApplication>
@@ -285,7 +285,7 @@ static QStringList CreateEmulatorArgs(const Configuration& info) {
 	}
 	args << "--game" << game;
 
-	const auto patch_plan = PatchesDialog::PatchPlanPath(info.title_id);
+	const auto patch_plan = Cheats::PlanPath(info.title_id);
 	if (QFileInfo::exists(patch_plan)) {
 		args << "--game-patch" << patch_plan;
 	}

src/launcher/src/patchesDialog.cpp

@@ -1,140 +1,309 @@
 #include "patchesDialog.h"
 
+#include "cheatFile.h"
 #include "configuration.h"
 
-#include <QCoreApplication>
-#include <QDebug>
 #include <QDialogButtonBox>
-#include <QDir>
 #include <QFile>
+#include <QFileInfo>
+#include <QHeaderView>
 #include <QJsonArray>
-#include <QJsonDocument>
 #include <QJsonObject>
 #include <QLabel>
 #include <QListWidget>
+#include <QMessageBox>
 #include <QPushButton>
-#include <QSaveFile>
+#include <QSplitter>
+#include <QStringList>
+#include <QTabWidget>
+#include <QTreeWidget>
 #include <QVBoxLayout>
 
+#include <algorithm>
+#include <utility>
+
+namespace {
+
+void ShowMods(QListWidget* list, const QJsonDocument& document, bool checkable) {
+	list->clear();
+	for (const auto& value: document.object().value(QStringLiteral("mods")).toArray()) {
+		const auto mod  = value.toObject();
+		auto*      item = new QListWidgetItem(mod.value(QStringLiteral("name")).toString(), list);
+		if (checkable) {
+			item->setFlags(item->flags() | Qt::ItemIsUserCheckable);
+			item->setCheckState(mod.value(QStringLiteral("enabled")).toBool(true) ? Qt::Checked
+			                                                                      : Qt::Unchecked);
+		}
+	}
+}
+
+QLabel* StatusLabel(QWidget* parent) {
+	auto* label = new QLabel(parent);
+	label->setWordWrap(true);
+	label->setTextFormat(Qt::PlainText);
+	return label;
+}
+
+} // namespace
+
 PatchesDialog::PatchesDialog(const Configuration& game, QWidget* parent)
-    : QDialog(parent), m_title_id(game.title_id.trimmed().toUpper()) {
+    : QDialog(parent), m_title_id(game.title_id.trimmed().toUpper()), m_version(game.gameVersion),
+      m_process(QFileInfo(game.elf.isEmpty() ? QStringLiteral("eboot.bin") : game.elf).fileName()) {
 	setAttribute(Qt::WA_DeleteOnClose);
 	setWindowTitle(tr("Cheats (experimental) - %1").arg(game.name));
-	resize(640, 480);
+	resize(800, 640);
 
-	auto* layout = new QVBoxLayout(this);
+	auto* layout     = new QVBoxLayout(this);
-	m_patches    = new QListWidget(this);
+	auto* game_label = StatusLabel(this);
-	m_status     = new QLabel(this);
+	game_label->setText(tr("%1 · Installed version: %2")
-	m_apply      = new QPushButton(tr("Apply selection"), this);
+	                        .arg(m_title_id, m_version.isEmpty() ? tr("Unknown") : m_version));
-	auto* close  = new QPushButton(tr("Close"), this);
+	layout->addWidget(game_label);
+	m_tabs = new QTabWidget(this);
+	layout->addWidget(m_tabs);
 
-	m_status->setWordWrap(true);
+	auto* remote        = new QWidget(m_tabs);
-	layout->addWidget(m_patches);
+	auto* remote_layout = new QVBoxLayout(remote);
-	layout->addWidget(m_status);
+	m_tabs->addTab(remote, tr("Remote"));
+	auto* credits = new QLabel(
+	    tr("Cheats by <a href=\"https://github.com/TeeKay87/HEN-Cheats-Collection\">TeeKay87 / HEN "
+	       "Cheats Collection</a> and its contributors."),
+	    remote);
+	credits->setOpenExternalLinks(true);
+	credits->setWordWrap(true);
+	remote_layout->addWidget(credits);
+	auto* support = StatusLabel(remote);
+	support->setText(tr("Only JSON cheats are supported. MC4 and SHN files are shown disabled. "
+	                    "Select a JSON file to preview its cheats."));
+	remote_layout->addWidget(support);
+	auto* split = new QSplitter(Qt::Vertical, remote);
+	m_files     = new QTreeWidget(split);
+	m_files->setHeaderLabels({tr("Version"), tr("Format"), tr("File")});
+	m_files->setRootIsDecorated(false);
+	m_files->setSelectionMode(QAbstractItemView::SingleSelection);
+	m_files->header()->setSectionResizeMode(0, QHeaderView::ResizeToContents);
+	m_files->header()->setSectionResizeMode(1, QHeaderView::ResizeToContents);
+	m_files->header()->setSectionResizeMode(2, QHeaderView::Stretch);
+	m_preview = new QListWidget(split);
+	remote_layout->addWidget(split, 1);
+	m_remote_status  = StatusLabel(remote);
+	m_preview_status = StatusLabel(remote);
+	remote_layout->addWidget(m_remote_status);
+	remote_layout->addWidget(m_preview_status);
+	auto* remote_buttons = new QDialogButtonBox(remote);
+	m_refresh            = remote_buttons->addButton(tr("Refresh"), QDialogButtonBox::ActionRole);
+	m_import = remote_buttons->addButton(tr("Import to Local"), QDialogButtonBox::ActionRole);
+	m_import->setEnabled(false);
+	remote_layout->addWidget(remote_buttons);
 
-	auto* buttons = new QDialogButtonBox(this);
+	auto* local        = new QWidget(m_tabs);
-	buttons->addButton(m_apply, QDialogButtonBox::ActionRole);
+	auto* local_layout = new QVBoxLayout(local);
-	buttons->addButton(close, QDialogButtonBox::RejectRole);
+	m_tabs->addTab(local, tr("Local"));
+	m_patches = new QListWidget(local);
+	m_status  = StatusLabel(local);
+	local_layout->addWidget(m_patches, 1);
+	local_layout->addWidget(m_status);
+	auto* local_buttons = new QDialogButtonBox(local);
+	auto* reload        = local_buttons->addButton(tr("Reload"), QDialogButtonBox::ActionRole);
+	m_apply = local_buttons->addButton(tr("Apply selection"), QDialogButtonBox::ActionRole);
+	local_layout->addWidget(local_buttons);
+	auto* buttons = new QDialogButtonBox(QDialogButtonBox::Close, this);
 	layout->addWidget(buttons);
-
+	connect(buttons, &QDialogButtonBox::rejected, this, &QDialog::close);
+	connect(reload, &QPushButton::clicked, this, &PatchesDialog::Load);
 	connect(m_apply, &QPushButton::clicked, this, &PatchesDialog::Save);
-	connect(close, &QPushButton::clicked, this, &QDialog::close);
+	connect(m_refresh, &QPushButton::clicked, this, &PatchesDialog::LoadRemote);
+	connect(m_import, &QPushButton::clicked, this, &PatchesDialog::ImportRemote);
+	connect(m_files, &QTreeWidget::currentItemChanged, this, &PatchesDialog::PreviewRemote);
 
+	m_repository = new Cheats::CheatRepository(this);
+	connect(
+	    m_repository, &Cheats::CheatRepository::CatalogLoaded, this,
+	    [this](QList<Cheats::RemoteFile> files, const QString& error) {
+		    std::stable_sort(files.begin(), files.end(), [this](const auto& a, const auto& b) {
+			    return (a.version == m_version) > (b.version == m_version);
+		    });
+		    m_remote_files = std::move(files);
+		    for (qsizetype index = 0; index < m_remote_files.size(); ++index) {
+			    const auto& file = m_remote_files[index];
+			    auto*       item = new QTreeWidgetItem(
+			        m_files, {file.version == m_version ? tr("%1 (installed)").arg(file.version)
+			                                            : file.version,
+			                  file.format.toUpper(), file.name});
+			    item->setData(0, Qt::UserRole, index);
+			    for (int column = 0; column < 3; ++column) {
+				    item->setToolTip(column, file.IsSupported()
+				                                 ? file.title
+				                                 : tr("%1 — %2 is not supported.")
+				                                       .arg(file.title, file.format.toUpper()));
+			    }
+			    if (!file.IsSupported()) {
+				    item->setFlags(item->flags() & ~(Qt::ItemIsEnabled | Qt::ItemIsSelectable));
+			    }
+		    }
+		    auto status =
+		        m_remote_files.isEmpty() && error.isEmpty()
+		            ? tr("No remote cheats found for %1.").arg(m_title_id)
+		            : tr("%1 remote file(s) for %2.").arg(m_remote_files.size()).arg(m_title_id);
+		    if (!error.isEmpty()) {
+			    status = tr("%1\nCould not load the complete collection: %2\nUse Refresh to retry.")
+			                 .arg(status, error);
+		    }
+		    m_remote_status->setText(status);
+		    m_refresh->setEnabled(true);
+	    });
+	connect(
+	    m_repository, &Cheats::CheatRepository::FileLoaded, this,
+	    [this](const QByteArray& data, QString error) {
+		    if (error.isEmpty()) {
+			    error = Cheats::ParseDocument(data, &m_remote_document);
+		    }
+		    if (!error.isEmpty()) {
+			    m_preview_status->setText(
+			        tr("Could not preview this file: %1\nSelect another file or refresh to retry.")
+			            .arg(error));
+			    return;
+		    }
+		    ShowMods(m_preview, m_remote_document, false);
+		    error = Cheats::ValidateImport(m_remote_document, m_title_id, m_version, m_process);
+		    const auto  root = m_remote_document.object();
+		    QStringList creators;
+		    for (const auto& value: root.value(QStringLiteral("credits")).toArray()) {
+			    if (value.isString()) {
+				    creators.append(value.toString());
+			    }
+		    }
+		    const auto metadata =
+		        tr("%1\nCredits: %2 · Version: %3")
+		            .arg(root.value(QStringLiteral("name")).toString(),
+		                 creators.isEmpty() ? root.value(QStringLiteral("author")).toString()
+		                                    : creators.join(QStringLiteral(", ")),
+		                 root.value(QStringLiteral("version")).toString());
+		    m_preview_status->setText(
+		        metadata + QStringLiteral("\n\n") +
+		        (error.isEmpty() ? tr("Import to Local, then select the cheats to enable. Changes "
+		                              "take effect on the next game launch.")
+		                         : error));
+		    m_import->setEnabled(error.isEmpty());
+	    });
 	Load();
-}
+	LoadRemote();
-
-bool PatchesDialog::IsSupportedTitleId(const QString& title_id) {
-	return title_id.trimmed().toUpper().startsWith(QStringLiteral("PPSA"));
-}
-
-QString PatchesDialog::PatchPlanPath(const QString& title_id) {
-	return QDir(QCoreApplication::applicationDirPath())
-	    .filePath(QStringLiteral("_Patches/%1.json").arg(title_id.trimmed().toUpper()));
 }
 
 void PatchesDialog::Load() {
-	QFile file(PatchPlanPath(m_title_id));
+	m_patches->clear();
+	m_local_data.clear();
+	m_local_document = {};
+	m_local_readable = false;
+	m_apply->setEnabled(false);
+	const auto path = Cheats::PlanPath(m_title_id);
+	if (path.isEmpty()) {
+		m_status->setText(tr("Unsupported title ID."));
+		return;
+	}
+	QFile file(path);
+	if (!file.exists()) {
+		m_local_readable = true;
+		m_status->setText(tr("No local cheat file: %1").arg(path));
+		return;
+	}
 	if (!file.open(QIODevice::ReadOnly)) {
-		m_status->setText(tr("No local cheat file: %1").arg(file.fileName()));
+		m_status->setText(tr("Could not read cheat file: %1").arg(file.errorString()));
-		m_apply->setEnabled(false);
 		return;
 	}
-
+	m_local_data = file.readAll();
-	const auto document = QJsonDocument::fromJson(file.readAll());
+	if (file.error() != QFile::NoError) {
-	if (document.isNull() || !document.isObject()) {
+		m_status->setText(tr("Could not read cheat file: %1").arg(file.errorString()));
-		m_status->setText(tr("Invalid cheat JSON in %1.").arg(file.fileName()));
-		m_apply->setEnabled(false);
 		return;
 	}
-
+	m_local_readable = true;
-	const auto root = document.object();
+	const auto error = Cheats::ParseDocument(m_local_data, &m_local_document);
-	if (!root.value(QStringLiteral("mods")).isArray()) {
+	if (!error.isEmpty()) {
-		m_status->setText(tr("Cheat JSON has no \"mods\" array in %1.").arg(file.fileName()));
+		m_status->setText(tr("%1\n%2").arg(error, path));
-		m_apply->setEnabled(false);
 		return;
 	}
-
+	ShowMods(m_patches, m_local_document, true);
-	const auto mods = root.value(QStringLiteral("mods")).toArray();
+	m_apply->setEnabled(m_patches->count() > 0);
-	for (const auto& value: mods) {
+	m_status->setText(tr("Loaded %1 cheat(s) from %2.").arg(m_patches->count()).arg(path));
-		if (!value.isObject()) {
-			m_status->setText(tr("Invalid cheat entry in %1.").arg(file.fileName()));
-			m_apply->setEnabled(false);
-			m_patches->clear();
-			return;
-		}
-		const auto mod     = value.toObject();
-		const auto name    = mod.value(QStringLiteral("name"));
-		const auto enabled = mod.value(QStringLiteral("enabled"));
-		if (!name.isString() || name.toString().isEmpty() ||
-		    (!enabled.isUndefined() && !enabled.isBool())) {
-			m_status->setText(tr("Invalid cheat entry in %1.").arg(file.fileName()));
-			m_apply->setEnabled(false);
-			m_patches->clear();
-			return;
-		}
-		auto* item = new QListWidgetItem(name.toString(), m_patches);
-		item->setFlags(item->flags() | Qt::ItemIsUserCheckable);
-		item->setCheckState(enabled.toBool(true) ? Qt::Checked : Qt::Unchecked);
-	}
-
-	m_apply->setEnabled(!mods.isEmpty());
-	m_status->setText(tr("Loaded %1 cheat(s) from %2.").arg(mods.size()).arg(file.fileName()));
 }
 
 void PatchesDialog::Save() {
-	const auto path = PatchPlanPath(m_title_id);
+	QList<bool> enabled;
-	QFile      input(path);
+	for (int index = 0; index < m_patches->count(); ++index) {
-	if (!input.open(QIODevice::ReadOnly)) {
+		enabled.append(m_patches->item(index)->checkState() == Qt::Checked);
+	}
+	const auto document = Cheats::WithSelection(m_local_document, enabled);
+	const auto error = Cheats::SaveDocument(Cheats::PlanPath(m_title_id), document, m_local_data);
+	if (!error.isEmpty()) {
+		m_status->setText(error);
 		return;
 	}
-
+	m_local_document = document;
-	auto document = QJsonDocument::fromJson(input.readAll());
+	m_local_data     = document.toJson();
-	input.close();
+	m_status->setText(tr("Cheat selection saved. Changes take effect on the next game launch."));
-	const auto changed_message = tr("Cheat file changed; reload the dialog.");
+}
-	if (!document.isObject()) {
+
-		m_status->setText(changed_message);
+void PatchesDialog::LoadRemote() {
-		return;
+	m_repository->CancelFetch();
-	}
+	m_files->clear();
-	auto root = document.object();
+	m_remote_files.clear();
-	auto mods = root.value(QStringLiteral("mods")).toArray();
+	m_preview->clear();
-	if (mods.size() != m_patches->count()) {
+	m_remote_document = {};
-		m_status->setText(changed_message);
+	m_import->setEnabled(false);
-		return;
+	m_refresh->setEnabled(false);
-	}
+	m_preview_status->clear();
-	for (int index = 0; index < mods.size(); index++) {
+	m_remote_status->setText(tr("Loading remote cheats…"));
-		auto mod = mods[index].toObject();
+	m_repository->Load(m_title_id);
-		mod.insert(QStringLiteral("enabled"), m_patches->item(index)->checkState() == Qt::Checked);
+}
-		mods[index] = mod;
+
-	}
+void PatchesDialog::PreviewRemote() {
-	root.insert(QStringLiteral("mods"), mods);
+	m_repository->CancelFetch();
-	document.setObject(root);
+	m_preview->clear();
-
+	m_remote_document = {};
-	QSaveFile output(path);
+	m_import->setEnabled(false);
-	if (!output.open(QIODevice::WriteOnly) || output.write(document.toJson()) < 0 ||
+	m_preview_status->clear();
-	    !output.commit()) {
+	const auto* item = m_files->currentItem();
-		qWarning() << "Could not save cheat file:" << output.errorString();
+	if (item == nullptr) {
-		m_status->setText(tr("Could not save cheat file: %1").arg(output.errorString()));
+		return;
-		return;
+	}
-	}
+	const auto index = item->data(0, Qt::UserRole).toInt();
-	m_status->setText(tr("Cheat selection saved."));
+	if (index < 0 || index >= m_remote_files.size() || !m_remote_files[index].IsSupported()) {
+		return;
+	}
+	m_preview_status->setText(tr("Loading cheat preview…"));
+	m_repository->Fetch(m_remote_files[index]);
+}
+
+void PatchesDialog::ImportRemote() {
+	const auto error = Cheats::ValidateImport(m_remote_document, m_title_id, m_version, m_process);
+	if (!error.isEmpty()) {
+		m_preview_status->setText(error);
+		return;
+	}
+	if (!m_local_readable) {
+		m_preview_status->setText(
+		    tr("Could not read the local cheat file. Open Local and reload it before importing."));
+		return;
+	}
+	const auto path = Cheats::PlanPath(m_title_id);
+	if (QFile::exists(path) &&
+	    QMessageBox::question(this, tr("Replace local cheats?"),
+	                          tr("Replace the local cheat file and selections for %1? Imported "
+	                             "cheats will start unchecked.")
+	                              .arg(m_title_id),
+	                          QMessageBox::Yes | QMessageBox::No,
+	                          QMessageBox::No) != QMessageBox::Yes) {
+		return;
+	}
+	const auto mods     = m_remote_document.object().value(QStringLiteral("mods")).toArray();
+	const auto document = Cheats::WithSelection(m_remote_document, QList<bool>(mods.size(), false));
+	const auto save_error = Cheats::SaveDocument(path, document, m_local_data);
+	if (!save_error.isEmpty()) {
+		m_preview_status->setText(save_error);
+		return;
+	}
+	Load();
+	m_status->setText(
+	    tr("Imported %1 cheat(s). Select cheats and apply your selection for the next game launch.")
+	        .arg(mods.size()));
+	m_tabs->setCurrentIndex(1);
 }