/* SPDX-FileCopyrightText: 2026 Project Tick
 * SPDX-FileContributor: Project Tick
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 *   MeshMC - A Custom Launcher for Minecraft
 *   Copyright (C) 2026 Project Tick
 *
 *   This program 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.
 *
 *   This program 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.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#pragma once

#include <QString>
#include <map>
#include <set>
#include <QStringList>
#include "tasks/Task.h"

namespace mojang_files
{

	using Hash = QString;
	extern const Hash empty_hash;

	// simple-ish path implementation. assumes always relative and does not
	// allow '..' entries
	class Path
	{
	  public:
		using parts_type = QStringList;

		Path() = default;
		Path(QString string)
		{ // NOLINT(IMPLICIT_CONSTRUCTOR)
			auto parts_in = string.split('/');
			for (auto& part : parts_in) {
				if (part.isEmpty() || part == ".") {
					continue;
				}
				if (part == "..") {
					if (parts.size()) {
						parts.pop_back();
					}
					continue;
				}
				parts.push_back(part);
			}
		}

		bool has_parent_path() const
		{
			return parts.size() > 0;
		}

		Path parent_path() const
		{
			if (parts.empty())
				return Path();
			return Path(parts.begin(), std::prev(parts.end()));
		}

		bool empty() const
		{
			return parts.empty();
		}

		int length() const
		{
			return parts.length();
		}

		bool operator==(const Path& rhs) const
		{
			return parts == rhs.parts;
		}

		bool operator!=(const Path& rhs) const
		{
			return parts != rhs.parts;
		}

		inline bool operator<(const Path& rhs) const
		{
			return compare(rhs) < 0;
		}

		parts_type::const_iterator begin() const
		{
			return parts.begin();
		}

		parts_type::const_iterator end() const
		{
			return parts.end();
		}

		QString toString() const
		{
			return parts.join("/");
		}

	  private:
		Path(const parts_type::const_iterator& start,
			 const parts_type::const_iterator& end)
		{
			auto cursor = start;
			while (cursor != end) {
				parts.push_back(*cursor);
				cursor++;
			}
		}
		int compare(const Path& p) const;

		parts_type parts;
	};

	enum class Compression { Raw, Lzma, Unknown };

	struct FileSource {
		Compression compression = Compression::Unknown;
		Hash hash;
		QString url;
		std::size_t size = 0;
		void upgrade(const FileSource& other)
		{
			if (compression == Compression::Unknown || other.size < size) {
				*this = other;
			}
		}
		bool isBad() const
		{
			return compression == Compression::Unknown;
		}
	};

	struct File {
		Hash hash;
		bool executable;
		std::uint64_t size = 0;
	};

	struct Package {
		static Package fromInspectedFolder(const QString& folderPath);
		static Package fromManifestFile(const QString& path);
		static Package fromManifestContents(const QByteArray& contents);

		explicit operator bool() const
		{
			return valid;
		}
		void addFolder(Path folder);
		void addFile(const Path& path, const File& file);
		void addLink(const Path& path, const Path& target);
		void addSource(const FileSource& source);

		std::map<Hash, FileSource> sources;
		bool valid = true;
		std::set<Path> folders;
		std::map<Path, File> files;
		std::map<Path, Path> symlinks;
	};

	struct FileDownload : FileSource {
		FileDownload(const FileSource& source, bool executable)
		{
			static_cast<FileSource&>(*this) = source;
			this->executable = executable;
		}
		bool executable = false;
	};

	struct UpdateOperations {
		static UpdateOperations resolve(const Package& from, const Package& to);
		bool valid = false;
		std::vector<Path> deletes;
		std::vector<Path> rmdirs;
		std::vector<Path> mkdirs;
		std::map<Path, FileDownload> downloads;
		std::map<Path, Path> mklinks;
		std::map<Path, bool> executable_fixes;
	};

} // namespace mojang_files