/* Copyright 2013-2017 MultiMC Contributors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <quazip.h>
#include <quazipdir.h>
#include <quazipfile.h>
#include <JlCompress.h>
#include "MMCZip.h"
#include "FileSystem.h"

#include <QDebug>

// ours
bool MMCZip::mergeZipFiles(QuaZip *into, QFileInfo from, QSet<QString> &contained, const JlCompress::FilterFunction filter)
{
	QuaZip modZip(from.filePath());
	modZip.open(QuaZip::mdUnzip);

	QuaZipFile fileInsideMod(&modZip);
	QuaZipFile zipOutFile(into);
	for (bool more = modZip.goToFirstFile(); more; more = modZip.goToNextFile())
	{
		QString filename = modZip.getCurrentFileName();
		if (filter && !filter(filename))
		{
			qDebug() << "Skipping file " << filename << " from "
						<< from.fileName() << " - filtered";
			continue;
		}
		if (contained.contains(filename))
		{
			qDebug() << "Skipping already contained file " << filename << " from "
						<< from.fileName();
			continue;
		}
		contained.insert(filename);

		if (!fileInsideMod.open(QIODevice::ReadOnly))
		{
			qCritical() << "Failed to open " << filename << " from " << from.fileName();
			return false;
		}

		QuaZipNewInfo info_out(fileInsideMod.getActualFileName());

		if (!zipOutFile.open(QIODevice::WriteOnly, info_out))
		{
			qCritical() << "Failed to open " << filename << " in the jar";
			fileInsideMod.close();
			return false;
		}
		if (!JlCompress::copyData(fileInsideMod, zipOutFile))
		{
			zipOutFile.close();
			fileInsideMod.close();
			qCritical() << "Failed to copy data of " << filename << " into the jar";
			return false;
		}
		zipOutFile.close();
		fileInsideMod.close();
	}
	return true;
}

// ours
bool MMCZip::createModdedJar(QString sourceJarPath, QString targetJarPath, const QList<Mod>& mods)
{
	QuaZip zipOut(targetJarPath);
	if (!zipOut.open(QuaZip::mdCreate))
	{
		QFile::remove(targetJarPath);
		qCritical() << "Failed to open the minecraft.jar for modding";
		return false;
	}
	// Files already added to the jar.
	// These files will be skipped.
	QSet<QString> addedFiles;

	// Modify the jar
	QListIterator<Mod> i(mods);
    i.toBack();
    while (i.hasPrevious())
	{
		const Mod &mod = i.previous();
		// do not merge disabled mods.
		if (!mod.enabled())
			continue;
		if (mod.type() == Mod::MOD_ZIPFILE)
		{
			if (!mergeZipFiles(&zipOut, mod.filename(), addedFiles))
			{
				zipOut.close();
				QFile::remove(targetJarPath);
				qCritical() << "Failed to add" << mod.filename().fileName() << "to the jar.";
				return false;
			}
		}
		else if (mod.type() == Mod::MOD_SINGLEFILE)
		{
			// FIXME: buggy - does not work with addedFiles
			auto filename = mod.filename();
			if (!JlCompress::compressFile(&zipOut, filename.absoluteFilePath(), filename.fileName()))
			{
				zipOut.close();
				QFile::remove(targetJarPath);
				qCritical() << "Failed to add" << mod.filename().fileName() << "to the jar.";
				return false;
			}
			addedFiles.insert(filename.fileName());
		}
		else if (mod.type() == Mod::MOD_FOLDER)
		{
			// FIXME: buggy - does not work with addedFiles
			auto filename = mod.filename();
			QString what_to_zip = filename.absoluteFilePath();
			QDir dir(what_to_zip);
			dir.cdUp();
			QString parent_dir = dir.absolutePath();
			if (!JlCompress::compressSubDir(&zipOut, what_to_zip, parent_dir, addedFiles))
			{
				zipOut.close();
				QFile::remove(targetJarPath);
				qCritical() << "Failed to add" << mod.filename().fileName() << "to the jar.";
				return false;
			}
			qDebug() << "Adding folder " << filename.fileName() << " from "
						<< filename.absoluteFilePath();
		}
		else
		{
			// Make sure we do not continue launching when something is missing or undefined...
			zipOut.close();
			QFile::remove(targetJarPath);
			qCritical() << "Failed to add unknown mod type" << mod.filename().fileName() << "to the jar.";
			return false;
		}
	}

	if (!mergeZipFiles(&zipOut, QFileInfo(sourceJarPath), addedFiles, [](const QString key){return !key.contains("META-INF");}))
	{
		zipOut.close();
		QFile::remove(targetJarPath);
		qCritical() << "Failed to insert minecraft.jar contents.";
		return false;
	}

	// Recompress the jar
	zipOut.close();
	if (zipOut.getZipError() != 0)
	{
		QFile::remove(targetJarPath);
		qCritical() << "Failed to finalize minecraft.jar!";
		return false;
	}
	return true;
}

// ours
QString MMCZip::findFolderOfFileInZip(QuaZip * zip, const QString & what, const QString &root)
{
	QuaZipDir rootDir(zip, root);
	for(auto fileName: rootDir.entryList(QDir::Files))
	{
		if(fileName == what)
			return root;
	}
	for(auto fileName: rootDir.entryList(QDir::Dirs))
	{
		QString result = findFolderOfFileInZip(zip, what, root + fileName);
		if(!result.isEmpty())
		{
			return result;
		}
	}
	return QString();
}

// ours
bool MMCZip::findFilesInZip(QuaZip * zip, const QString & what, QStringList & result, const QString &root)
{
	QuaZipDir rootDir(zip, root);
	for(auto fileName: rootDir.entryList(QDir::Files))
	{
		if(fileName == what)
		{
			result.append(root);
			return true;
		}
	}
	for(auto fileName: rootDir.entryList(QDir::Dirs))
	{
		findFilesInZip(zip, what, result, root + fileName);
	}
	return !result.isEmpty();
}


// ours
QStringList MMCZip::extractSubDir(QuaZip *zip, const QString & subdir, const QString &target)
{
	QDir directory(target);
	QStringList extracted;
	if (!zip->goToFirstFile())
	{
		return QStringList();
	}
	do
	{
		QString name = zip->getCurrentFileName();
		if(!name.startsWith(subdir))
		{
			continue;
		}
		name.remove(0, subdir.size());
		QString absFilePath = directory.absoluteFilePath(name);
		if(name.isEmpty())
		{
			absFilePath += "/";
		}
		if (!JlCompress::extractFile(zip, "", absFilePath))
		{
			JlCompress::removeFile(extracted);
			return QStringList();
		}
		extracted.append(absFilePath);
	} while (zip->goToNextFile());
	return extracted;
}

// ours
QStringList MMCZip::extractDir(QString fileCompressed, QString dir)
{
	QuaZip zip(fileCompressed);
	if (!zip.open(QuaZip::mdUnzip))
	{
		return {};
	}
	return MMCZip::extractSubDir(&zip, "", dir);
}