/* 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 "LauncherPartLaunch.h"
#include <QCoreApplication>
#include <launch/LaunchTask.h>
#include <minecraft/MinecraftInstance.h>
#include <FileSystem.h>
#include <Commandline.h>
#include <QStandardPaths>
#include "Env.h"

LauncherPartLaunch::LauncherPartLaunch(LaunchTask *parent) : LaunchStep(parent)
{
	connect(&m_process, &LoggedProcess::log, this, &LauncherPartLaunch::logLines);
	connect(&m_process, &LoggedProcess::stateChanged, this, &LauncherPartLaunch::on_state);
}

#ifdef Q_OS_WIN
// returns 8.3 file format from long path
#include <windows.h>
QString shortPathName(const QString & file)
{
	auto input = file.toStdWString();
	std::wstring output;
	long length = GetShortPathNameW(input.c_str(), NULL, 0);
	// NOTE: this resizing might seem weird...
	// when GetShortPathNameW fails, it returns length including null character
	// when it succeeds, it returns length excluding null character
	// See: https://msdn.microsoft.com/en-us/library/windows/desktop/aa364989(v=vs.85).aspx
	output.resize(length);
	GetShortPathNameW(input.c_str(),(LPWSTR)output.c_str(),length);
	output.resize(length-1);
	QString ret = QString::fromStdWString(output);
	return ret;
}
#endif

// if the string survives roundtrip through local 8bit encoding...
bool fitsInLocal8bit(const QString & string)
{
	return string == QString::fromLocal8Bit(string.toLocal8Bit());
}

void LauncherPartLaunch::executeTask()
{
	auto instance = m_parent->instance();
	std::shared_ptr<MinecraftInstance> minecraftInstance = std::dynamic_pointer_cast<MinecraftInstance>(instance);

	m_launchScript = minecraftInstance->createLaunchScript(m_session);
	QStringList args = minecraftInstance->javaArguments();
	QString allArgs = args.join(", ");
	emit logLine("Java Arguments:\n[" + m_parent->censorPrivateInfo(allArgs) + "]\n\n", MessageLevel::MultiMC);

	auto javaPath = FS::ResolveExecutable(instance->settings()->get("JavaPath").toString());

	m_process.setProcessEnvironment(instance->createEnvironment());

	// make detachable - this will keep the process running even if the object is destroyed
	m_process.setDetachable(true);

	auto classPath = minecraftInstance->getClassPath();
	classPath.prepend(FS::PathCombine(ENV.getJarsPath(), "NewLaunch.jar"));

	auto natPath = minecraftInstance->getNativePath();
#ifdef Q_OS_WIN
	if (!fitsInLocal8bit(natPath))
	{
		args << "-Djava.library.path=" + shortPathName(natPath);
	}
	else
	{
		args << "-Djava.library.path=" + natPath;
	}
#else
	args << "-Djava.library.path=" + natPath;
#endif

	args << "-cp";
#ifdef Q_OS_WIN
	QStringList processed;
	for(auto & item: classPath)
	{
		if (!fitsInLocal8bit(item))
		{
			processed << shortPathName(item);
		}
		else
		{
			processed << item;
		}
	}
	args << processed.join(';');
#else
	args << classPath.join(':');
#endif
	args << "org.multimc.EntryPoint";

	qDebug() << args.join(' ');

	QString wrapperCommandStr = instance->getWrapperCommand().trimmed();
	if(!wrapperCommandStr.isEmpty())
	{
		auto wrapperArgs = Commandline::splitArgs(wrapperCommandStr);
		auto wrapperCommand = wrapperArgs.takeFirst();
		auto realWrapperCommand = QStandardPaths::findExecutable(wrapperCommand);
		if (realWrapperCommand.isEmpty())
		{
			QString reason = tr("The wrapper command \"%1\" couldn't be found.").arg(wrapperCommand);
			emit logLine(reason, MessageLevel::Fatal);
			emitFailed(reason);
			return;
		}
		emit logLine("Wrapper command is:\n" + wrapperCommandStr + "\n\n", MessageLevel::MultiMC);
		args.prepend(javaPath);
		m_process.start(wrapperCommand, wrapperArgs + args);
	}
	else
	{
		m_process.start(javaPath, args);
	}
}

void LauncherPartLaunch::on_state(LoggedProcess::State state)
{
	switch(state)
	{
		case LoggedProcess::FailedToStart:
		{
			//: Error message displayed if instace can't start
			QString reason = tr("Could not launch minecraft!");
			emit logLine(reason, MessageLevel::Fatal);
			emitFailed(reason);
			return;
		}
		case LoggedProcess::Aborted:
		case LoggedProcess::Crashed:

		{
			m_parent->setPid(-1);
			emitFailed("Game crashed.");
			return;
		}
		case LoggedProcess::Finished:
		{
			m_parent->setPid(-1);
			// if the exit code wasn't 0, report this as a crash
			auto exitCode = m_process.exitCode();
			if(exitCode != 0)
			{
				emitFailed("Game crashed.");
				return;
			}
			//FIXME: make this work again
			// m_postlaunchprocess.processEnvironment().insert("INST_EXITCODE", QString(exitCode));
			// run post-exit
			emitSucceeded();
			break;
		}
		case LoggedProcess::Running:
			emit logLine(tr("Minecraft process ID: %1\n\n").arg(m_process.processId()), MessageLevel::MultiMC);
			m_parent->setPid(m_process.processId());
			m_parent->instance()->setLastLaunch();
			// send the launch script to the launcher part
			m_process.write(m_launchScript.toUtf8());

			mayProceed = true;
			emit readyForLaunch();
			break;
		default:
			break;
	}
}

void LauncherPartLaunch::setWorkingDirectory(const QString &wd)
{
	m_process.setWorkingDirectory(wd);
}

void LauncherPartLaunch::proceed()
{
	if(mayProceed)
	{
		QString launchString("launch\n");
		m_process.write(launchString.toUtf8());
		mayProceed = false;
	}
}

bool LauncherPartLaunch::abort()
{
	if(mayProceed)
	{
		mayProceed = false;
		QString launchString("abort\n");
		m_process.write(launchString.toUtf8());
	}
	else
	{
		auto state = m_process.state();
		if (state == LoggedProcess::Running || state == LoggedProcess::Starting)
		{
			m_process.kill();
		}
	}
	return true;
}