/* Copyright 2013 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 <QList>
#include <QJsonObject>
#include <QJsonArray>
#include <QJsonDocument>
#include <QFile>
#include <QFileInfo>
#include <QMessageBox>
#include <QObject>
#include <QDir>
#include <QDebug>
#include <modutils.h>

#include "logic/minecraft/OneSixVersionBuilder.h"
#include "logic/minecraft/VersionFinal.h"
#include "logic/minecraft/OneSixRule.h"
#include "logic/minecraft/VersionFile.h"

#include "logic/OneSixInstance.h"
#include "logic/MMCJson.h"

#include "logger/QsLog.h"

OneSixVersionBuilder::OneSixVersionBuilder()
{
}

void OneSixVersionBuilder::build(VersionFinal *version, OneSixInstance *instance, const QStringList &external)
{
	OneSixVersionBuilder builder;
	builder.m_version = version;
	builder.m_instance = instance;
	builder.buildInternal(external);
}

void OneSixVersionBuilder::readJsonAndApplyToVersion(VersionFinal *version,
													 const QJsonObject &obj)
{
	OneSixVersionBuilder builder;
	builder.m_version = version;
	builder.m_instance = 0;
	builder.readJsonAndApply(obj);
}

void OneSixVersionBuilder::buildInternal(const QStringList &external)
{
	m_version->versionFiles.clear();

	QDir root(m_instance->instanceRoot());
	QDir patches(root.absoluteFilePath("patches/"));

	// if we do external files, do just those.
	if (!external.isEmpty())
	{
		int externalOrder = -1;
		for (auto fileName : external)
		{
			QLOG_INFO() << "Reading" << fileName;
			auto file =
				parseJsonFile(QFileInfo(fileName), false, fileName.endsWith("pack.json"));
			file->name = QFileInfo(fileName).fileName();
			file->fileId = "org.multimc.external." + file->name;
			file->order = (externalOrder += 1);
			file->version = QString();
			file->mcVersion = QString();
			m_version->versionFiles.append(file);
		}
	}
	// else, if there's custom json, we just do that.
	else if (QFile::exists(root.absoluteFilePath("custom.json")))
	{
		QLOG_INFO() << "Reading custom.json";
		auto file = parseJsonFile(QFileInfo(root.absoluteFilePath("custom.json")), false);
		file->name = "custom.json";
		file->filename = "custom.json";
		file->fileId = "org.multimc.custom.json";
		file->order = -1;
		file->version = QString();
		m_version->versionFiles.append(file);
		// QObject::tr("The version descriptors of this instance are not compatible with the
		// current version of MultiMC"));
		// QObject::tr("Error while applying %1. Please check MultiMC-0.log for more info.")
	}
	// version.json -> patches/*.json -> user.json
	else
		do
		{
			// version.json
			QLOG_INFO() << "Reading version.json";
			auto file = parseJsonFile(QFileInfo(root.absoluteFilePath("version.json")), false);
			file->name = "Minecraft";
			file->fileId = "org.multimc.version.json";
			file->order = -1;
			file->version = m_instance->intendedVersionId();
			file->mcVersion = m_instance->intendedVersionId();
			m_version->versionFiles.append(file);
			// QObject::tr("Error while applying %1. Please check MultiMC-0.log for more
			// info.").arg(root.absoluteFilePath("version.json")));

			// patches/
			// load all, put into map for ordering, apply in the right order

			QMap<int, QPair<QString, VersionFilePtr>> files;
			for (auto info : patches.entryInfoList(QStringList() << "*.json", QDir::Files))
			{
				QLOG_INFO() << "Reading" << info.fileName();
				auto file = parseJsonFile(info, true);
				if (files.contains(file->order))
				{
					throw VersionBuildError(QObject::tr("%1 has the same order as %2").arg(
						file->fileId, files[file->order].second->fileId));
				}
				files.insert(file->order, qMakePair(info.fileName(), file));
			}
			for (auto order : files.keys())
			{
				auto &filePair = files[order];
				m_version->versionFiles.append(filePair.second);
			}
		} while (0);

	// some final touches
	m_version->finalize();
}



void OneSixVersionBuilder::readJsonAndApply(const QJsonObject &obj)
{
	m_version->clear();

	auto file = VersionFile::fromJson(QJsonDocument(obj), QString(), false);
	// QObject::tr("Error while reading. Please check MultiMC-0.log for more info."));

	file->applyTo(m_version);
	m_version->versionFiles.append(file);
	// QObject::tr("Error while applying. Please check MultiMC-0.log for more info."));
	// QObject::tr("The version descriptors of this instance are not compatible with the current
	// version of MultiMC"));
}

VersionFilePtr OneSixVersionBuilder::parseJsonFile(const QFileInfo &fileInfo,
												   const bool requireOrder, bool isFTB)
{
	QFile file(fileInfo.absoluteFilePath());
	if (!file.open(QFile::ReadOnly))
	{
		throw JSONValidationError(QObject::tr("Unable to open the version file %1: %2.")
									  .arg(fileInfo.fileName(), file.errorString()));
	}
	QJsonParseError error;
	QJsonDocument doc = QJsonDocument::fromJson(file.readAll(), &error);
	if (error.error != QJsonParseError::NoError)
	{
		throw JSONValidationError(QObject::tr("Unable to process the version file %1: %2 at %3.")
									  .arg(fileInfo.fileName(), error.errorString())
									  .arg(error.offset));
	}
	return VersionFile::fromJson(doc, file.fileName(), requireOrder, isFTB);
	// QObject::tr("Error while reading %1. Please check MultiMC-0.log for more
	// info.").arg(file.fileName());
}

QMap<QString, int> OneSixVersionBuilder::readOverrideOrders(OneSixInstance *instance)
{
	QMap<QString, int> out;

	// make sure the order file exists
	if (!QDir(instance->instanceRoot()).exists("order.json"))
		return out;

	// and it can be opened
	QFile orderFile(instance->instanceRoot() + "/order.json");
	if (!orderFile.open(QFile::ReadOnly))
	{
		QLOG_ERROR() << "Couldn't open" << orderFile.fileName()
					 << " for reading:" << orderFile.errorString();
		QLOG_WARN() << "Ignoring overriden order";
		return out;
	}

	// and it's valid JSON
	QJsonParseError error;
	QJsonDocument doc = QJsonDocument::fromJson(orderFile.readAll(), &error);
	if (error.error != QJsonParseError::NoError)
	{
		QLOG_ERROR() << "Couldn't parse" << orderFile.fileName() << ":" << error.errorString();
		QLOG_WARN() << "Ignoring overriden order";
		return out;
	}

	// and then read it and process it if all above is true.
	try
	{
		auto obj = MMCJson::ensureObject(doc);
		for (auto it = obj.begin(); it != obj.end(); ++it)
		{
			if (it.key().startsWith("org.multimc."))
			{
				continue;
			}
			out.insert(it.key(), MMCJson::ensureInteger(it.value()));
		}
	}
	catch (JSONValidationError &err)
	{
		QLOG_ERROR() << "Couldn't parse" << orderFile.fileName() << ": bad file format";
		QLOG_WARN() << "Ignoring overriden order";
		return out;
	}
	return out;
}

bool OneSixVersionBuilder::writeOverrideOrders(const QMap<QString, int> &order,
											   OneSixInstance *instance)
{
	QJsonObject obj;
	for (auto it = order.cbegin(); it != order.cend(); ++it)
	{
		if (it.key().startsWith("org.multimc."))
		{
			continue;
		}
		obj.insert(it.key(), it.value());
	}
	QFile orderFile(instance->instanceRoot() + "/order.json");
	if (!orderFile.open(QFile::WriteOnly))
	{
		QLOG_ERROR() << "Couldn't open" << orderFile.fileName()
					 << "for writing:" << orderFile.errorString();
		return false;
	}
	orderFile.write(QJsonDocument(obj).toJson(QJsonDocument::Indented));
	return true;
}