/******************************************************************************
 * Icinga 2                                                                   *
 * Copyright (C) 2012-2014 Icinga Development Team (http://www.icinga.org)    *
 *                                                                            *
 * 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 2             *
 * 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, write to the Free Software Foundation     *
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.             *
 ******************************************************************************/

#include "cli/repositoryutility.hpp"
#include "cli/clicommand.hpp"
#include "base/logger.hpp"
#include "base/application.hpp"
#include "base/convert.hpp"
#include "base/serializer.hpp"
#include "base/netstring.hpp"
#include "base/stdiostream.hpp"
#include "base/debug.hpp"
#include "base/objectlock.hpp"
#include "base/console.hpp"
#include <boost/foreach.hpp>
#include <boost/algorithm/string/join.hpp>
#include <boost/algorithm/string/replace.hpp>
#include <fstream>
#include <iostream>

using namespace icinga;

String RepositoryUtility::GetRepositoryDPath(void)
{
	return Application::GetSysconfDir() + "/icinga2/repository.d";
}

String RepositoryUtility::GetRepositoryDObjectsPath(const String& type, const String& hostname)
{
	if (type == "Host")
		return GetRepositoryDPath() + "/hosts";
	else if (type == "Service")
		return GetRepositoryDPath() + "/hosts/" + hostname;
	else if (type == "Zone")
		return GetRepositoryDPath() + "/zones";
	else if (type == "Endpoints")
		return GetRepositoryDPath() + "/endpoints";
	else
		return GetRepositoryDPath();
}

String RepositoryUtility::GetRepositoryChangeLogPath(void)
{
	return Application::GetLocalStateDir() + "/lib/icinga2/repository";
}

void RepositoryUtility::PrintObjects(std::ostream& fp, const String& type)
{
	std::vector<String> objects;
	GetObjects(type, objects);

	BOOST_FOREACH(const String& object, objects) {
		Dictionary::Ptr obj = GetObjectFromRepository(GetRepositoryDObjectsPath(type) + "/" + object + ".conf");

		if (obj) {
			fp << "Object Name: " << object << "\n";
			fp << JsonSerialize(obj);
		}
	}
}

/* public interface, only logs changes */
bool RepositoryUtility::AddObject(const String& name, const String& type, const Dictionary::Ptr& attr)
{
	/* add a new changelog entry by timestamp */
	String path = GetRepositoryChangeLogPath() + "/" + Convert::ToString(static_cast<long>(Utility::GetTime())) + ".change";

	Dictionary::Ptr change = make_shared<Dictionary>();

	change->Set("timestamp", Utility::GetTime());
	change->Set("name", name);
	change->Set("type", type);
	change->Set("command", "add");
	change->Set("attr", attr);

	return WriteObjectToRepositoryChangeLog(path, change);
}

bool RepositoryUtility::RemoveObject(const String& name, const String& type)
{
	/* add a new changelog entry by timestamp */
	String path = GetRepositoryChangeLogPath() + "/" + Convert::ToString(static_cast<long>(Utility::GetTime())) + ".change";

	Dictionary::Ptr change = make_shared<Dictionary>();

	change->Set("timestamp", Utility::GetTime());
	change->Set("name", name);
	change->Set("type", type);
	change->Set("command", "remove");

	return WriteObjectToRepositoryChangeLog(path, change);
}

bool RepositoryUtility::CommitChangeLog(void)
{
	GetChangeLog(boost::bind(RepositoryUtility::CommitChange, _1));

	return true;
}

void RepositoryUtility::PrintChangeLog(std::ostream& fp)
{
	Array::Ptr changelog = make_shared<Array>();

	GetChangeLog(boost::bind(RepositoryUtility::CollectChange, _1, boost::ref(changelog)));

	ObjectLock olock(changelog);

	std::cout << "Changes to be committed:\n";

	BOOST_FOREACH(const Value& entry, changelog) {
		std::cout << JsonSerialize(entry) << "\n"; //TODO better formatting
	}
}

bool RepositoryUtility::SetObjectAttribute(const String& name, const String& type, const String& attr, const Value& val)
{
	//TODO: Implement modification commands
	return true;
}

/* internal implementation when changes are committed */
bool RepositoryUtility::AddObjectInternal(const String& name, const String& type, const Dictionary::Ptr& attr)
{
	String path = GetRepositoryDObjectsPath(type, name) + "/" + name + ".conf";

	return WriteObjectToRepository(path, name, type, attr);
}

bool RepositoryUtility::RemoveObjectInternal(const String& name, const String& type)
{
	String path = GetRepositoryDObjectsPath(type, name) + "/" + name + ".conf";

	return RemoveObjectFileInternal(path);
}

bool RepositoryUtility::RemoveObjectFileInternal(const String& path)
{
	if (!Utility::PathExists(path) ) {
		Log(LogCritical, "cli", "Cannot remove '" + path + "'. Does not exist.");
		return false;
	}

	if (unlink(path.CStr()) < 0) {
		Log(LogCritical, "cli", "Cannot remove file '" + path +
		    "'. Failed with error code " + Convert::ToString(errno) + ", \"" + Utility::FormatErrorNumber(errno) + "\".");
		return false;
	}

	return true;
}

bool RepositoryUtility::SetObjectAttributeInternal(const String& name, const String& type, const String& attr, const Value& val)
{
	//Fixme
	String path = GetRepositoryDObjectsPath(type, name) + "/" + name + ".conf";

	Dictionary::Ptr obj = GetObjectFromRepository(path);

	if (!obj) {
		Log(LogCritical, "cli")
		    << "Can't get object " << name << " from repository.\n";
		return false;
	}

	obj->Set(attr, val);

	std::cout << "Writing object '" << name << "' to path '" << path << "'.\n";

	//TODO: Create a patch file
	if(!WriteObjectToRepository(path, name, type, obj)) {
		Log(LogCritical, "cli")
		    << "Can't write object " << name << " to repository.\n";
		return false;
	}

	return true;
}

bool RepositoryUtility::WriteObjectToRepository(const String& path, const String& name, const String& type, const Dictionary::Ptr& item)
{
	Log(LogInformation, "cli", "Dumping config items to file '" + path + "'");

	Utility::MkDirP(Utility::DirName(path), 0755);

	String tempPath = path + ".tmp";

        std::ofstream fp(tempPath.CStr(), std::ofstream::out | std::ostream::trunc);
        SerializeObject(fp, name, type, item);
	fp << std::endl;
        fp.close();

#ifdef _WIN32
	_unlink(path.CStr());
#endif /* _WIN32 */

	if (rename(tempPath.CStr(), path.CStr()) < 0) {
		BOOST_THROW_EXCEPTION(posix_error()
		    << boost::errinfo_api_function("rename")
		    << boost::errinfo_errno(errno)
		    << boost::errinfo_file_name(tempPath));
	}

	return true;
}

Dictionary::Ptr RepositoryUtility::GetObjectFromRepository(const String& filename)
{
	//TODO: Parse existing configuration objects
	return Dictionary::Ptr();
}

bool RepositoryUtility::WriteObjectToRepositoryChangeLog(const String& path, const Dictionary::Ptr& item)
{
	Log(LogInformation, "cli", "Dumping changelog items to file '" + path + "'");

	Utility::MkDirP(Utility::DirName(path), 0755);

	String tempPath = path + ".tmp";

        std::ofstream fp(tempPath.CStr(), std::ofstream::out | std::ostream::trunc);
        fp << JsonSerialize(item);
        fp.close();

#ifdef _WIN32
	_unlink(path.CStr());
#endif /* _WIN32 */

	if (rename(tempPath.CStr(), path.CStr()) < 0) {
		BOOST_THROW_EXCEPTION(posix_error()
		    << boost::errinfo_api_function("rename")
		    << boost::errinfo_errno(errno)
		    << boost::errinfo_file_name(tempPath));
	}

	return true;
}

Dictionary::Ptr RepositoryUtility::GetObjectFromRepositoryChangeLog(const String& filename)
{
	std::fstream fp;
	fp.open(filename.CStr(), std::ifstream::in);

	if (!fp)
		return Dictionary::Ptr();

	String content((std::istreambuf_iterator<char>(fp)), std::istreambuf_iterator<char>());

	fp.close();

	return JsonDeserialize(content);
}


/*
 * collect functions
 */
bool RepositoryUtility::GetObjects(const String& type, std::vector<String>& objects)
{
	String path = GetRepositoryDPath() + "/";

	if (type == "service")
		path = "hosts/*";
	else
		path = type;

	if (!Utility::Glob(path + "/*.conf",
	    boost::bind(&RepositoryUtility::CollectObjects, _1, boost::ref(objects)), GlobFile)) {
		Log(LogCritical, "cli", "Cannot access path '" + path + "'.");
		return false;
	}

	return true;
}

void RepositoryUtility::CollectObjects(const String& object_file, std::vector<String>& objects)
{
	String object = Utility::BaseName(object_file);
	boost::algorithm::replace_all(object, ".conf", "");

	Log(LogDebug, "cli", "Adding object: " + object);
	objects.push_back(object);
}


bool RepositoryUtility::GetChangeLog(const boost::function<void (const Dictionary::Ptr&)>& callback)
{
	std::vector<String> changelog;
	String path = GetRepositoryChangeLogPath() + "/";

	if (!Utility::Glob(path + "/*.change",
	    boost::bind(&RepositoryUtility::CollectChangeLog, _1, boost::ref(changelog)), GlobFile)) {
		Log(LogCritical, "cli", "Cannot access path '" + path + "'.");
		return false;
	}

	/* sort by timestamp ascending */
	std::sort(changelog.begin(), changelog.end());

	BOOST_FOREACH(const String& entry, changelog) {
		Dictionary::Ptr change = GetObjectFromRepositoryChangeLog(path + entry + ".change");

		Log(LogInformation, "cli")
		    << "Collecting entry " << entry << "\n";

		if (change)
			callback(change);
	}

	return true;
}

void RepositoryUtility::CollectChangeLog(const String& change_file, std::vector<String>& changelog)
{
	String file = Utility::BaseName(change_file);
	boost::algorithm::replace_all(file, ".change", "");

	Log(LogDebug, "cli", "Adding change file: " + file);
	changelog.push_back(file);
}

void RepositoryUtility::CommitChange(const Dictionary::Ptr& change)
{
	Log(LogInformation, "cli")
	   << "Got change " << change->Get("name");

	String name = change->Get("name");
	String type = change->Get("type");
	String command = change->Get("command");
	Dictionary::Ptr attr;

	if (change->Contains("attr")) {
		attr = change->Get("attr");
	}

	if (command == "add") {
		AddObjectInternal(name, type, attr);
	}
	else if (command == "remove") {
		RemoveObjectInternal(name, type);
	}
}

void RepositoryUtility::CollectChange(const Dictionary::Ptr& change, Array::Ptr& changes)
{
	changes->Add(change);
}


/*
 * print helpers for configuration
 * TODO: Move into a separate class
 */
void RepositoryUtility::SerializeObject(std::ostream& fp, const String& name, const String& type, const Dictionary::Ptr& object)
{
	fp << "object " << type << " \"" << name << "\" {\n";

	if (object->Contains("templates"))
		fp << "\t" << "import \"" << object->Get("templates") << "\"\n";

	BOOST_FOREACH(const Dictionary::Pair& kv, object) {
		if (kv.first == "templates") {
			continue;
		} else {
			fp << "\t" << kv.first << " = ";
			FormatValue(fp, kv.second);
		}
		fp << "\n";
	}
	fp << "}\n";
}

void RepositoryUtility::FormatValue(std::ostream& fp, const Value& val)
{
        if (val.IsObjectType<Array>()) {
                FormatArray(fp, val);
                return;
        }

        if (val.IsString()) {
                fp << "\"" << Convert::ToString(val) << "\"";
                return;
        }

        fp << Convert::ToString(val);
}

void RepositoryUtility::FormatArray(std::ostream& fp, const Array::Ptr& arr)
{
        bool first = true;

        fp << "[ ";

        if (arr) {
                ObjectLock olock(arr);
                BOOST_FOREACH(const Value& value, arr) {
                        if (first)
                                first = false;
                        else
                                fp << ", ";

                        FormatValue(fp, value);
                }
        }

        if (!first)
                fp << " ";

        fp << "]";
}