/*
 * InspIRCd -- Internet Relay Chat Daemon
 *
 *   Copyright (C) 2021 Herman <GermanAizek@yandex.ru>
 *   Copyright (C) 2019 Matt Schatz <genius3000@g3k.solutions>
 *   Copyright (C) 2018 linuxdaemon <linuxdaemon.irc@gmail.com>
 *   Copyright (C) 2013, 2017-2018, 2020, 2022 Sadie Powell <sadie@witchery.services>
 *   Copyright (C) 2012, 2019 Robby <robby@chatbelgie.be>
 *   Copyright (C) 2012, 2014, 2016 Attila Molnar <attilamolnar@hush.com>
 *   Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
 *   Copyright (C) 2007-2008 Dennis Friis <peavey@inspircd.org>
 *   Copyright (C) 2006-2008 Robin Burchell <robin+git@viroteck.net>
 *   Copyright (C) 2006 Craig Edwards <brain@inspircd.org>
 *
 * This file is part of InspIRCd.  InspIRCd 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, version 2.
 *
 * 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 <http://www.gnu.org/licenses/>.
 */


#include "inspircd.h"
#include "duration.h"
#include "modules/stats.h"
#include "xline.h"

namespace
{
	bool silent;
}

/** Holds a SVSHold item
 */
class SVSHold final
	: public XLine
{
public:
	std::string nickname;

	SVSHold(time_t s_time, unsigned long d, const std::string& src, const std::string& re, const std::string& nick)
		: XLine(s_time, d, src, re, "SVSHOLD")
		, nickname(nick)
	{
	}

	bool Matches(User* u) override
	{
		return u->nick == nickname;
	}

	bool Matches(const std::string& s) override
	{
		return InspIRCd::Match(s, nickname);
	}

	void DisplayExpiry() override
	{
		if (!silent)
			XLine::DisplayExpiry();
	}

	const std::string& Displayable() override
	{
		return nickname;
	}
};

/** An XLineFactory specialized to generate SVSHOLD pointers
 */
class SVSHoldFactory final
	: public XLineFactory
{
public:
	SVSHoldFactory()
		: XLineFactory("SVSHOLD")
	{
	}

	XLine* Generate(time_t set_time, unsigned long duration, const std::string& source, const std::string& reason, const std::string& xline_specific_mask) override
	{
		return new SVSHold(set_time, duration, source, reason, xline_specific_mask);
	}

	bool AutoApplyToUserList(XLine* x) override
	{
		return false;
	}
};

class CommandSvshold final
	: public Command
{
public:
	CommandSvshold(Module* Creator)
		: Command(Creator, "SVSHOLD", 1)
	{
		access_needed = CmdAccess::OPERATOR;
		syntax = { "<nick> [<duration> :<reason>]" };
	}

	CmdResult Handle(User* user, const Params& parameters) override
	{
		/* syntax: svshold nickname time :reason goes here */
		/* 'time' is a human-readable timestring, like 2d3h2s. */

		if (!user->server->IsService())
		{
			/* don't allow SVSHOLD from non-services */
			return CmdResult::FAILURE;
		}

		if (parameters.size() == 1)
		{
			std::string reason;

			if (ServerInstance->XLines->DelLine(parameters[0].c_str(), "SVSHOLD", reason, user))
			{
				if (!silent)
					ServerInstance->SNO.WriteToSnoMask('x', "{} removed SVSHOLD on {}: {}", user->nick, parameters[0], reason);
			}
			else
			{
				user->WriteNotice("*** SVSHOLD " + parameters[0] + " not found on the list.");
			}
		}
		else
		{
			if (parameters.size() < 3)
				return CmdResult::FAILURE;

			unsigned long duration;
			if (!Duration::TryFrom(parameters[1], duration))
			{
				user->WriteNotice("*** Invalid duration for SVSHOLD.");
				return CmdResult::FAILURE;
			}

			auto* r = new SVSHold(ServerInstance->Time(), duration, user->nick, parameters[2], parameters[0]);
			if (ServerInstance->XLines->AddLine(r, user))
			{
				if (silent)
					return CmdResult::SUCCESS;

				if (!duration)
				{
					ServerInstance->SNO.WriteToSnoMask('x', "{} added a permanent SVSHOLD on {}: {}", user->nick, parameters[0], parameters[2]);
				}
				else
				{
					ServerInstance->SNO.WriteToSnoMask('x', "{} added a timed SVSHOLD on {}, expires in {} (on {}): {}",
						user->nick, parameters[0], Duration::ToString(duration),
						InspIRCd::TimeString(ServerInstance->Time() + duration), parameters[2]);
				}
			}
			else
			{
				delete r;
				return CmdResult::FAILURE;
			}
		}

		return CmdResult::SUCCESS;
	}

	RouteDescriptor GetRouting(User* user, const Params& parameters) override
	{
		return ROUTE_BROADCAST;
	}
};

class ModuleSVSHold final
	: public Module
	, public Stats::EventListener
{
private:
	CommandSvshold cmd;
	SVSHoldFactory s;

public:
	ModuleSVSHold()
		: Module(VF_VENDOR | VF_COMMON, "Adds the /SVSHOLD command which allows services to reserve nicknames.")
		, Stats::EventListener(this)
		, cmd(this)
	{
	}

	void init() override
	{
		ServerInstance->XLines->RegisterFactory(&s);
	}

	void ReadConfig(ConfigStatus& status) override
	{
		const auto& tag = ServerInstance->Config->ConfValue("svshold");
		silent = tag->getBool("silent", true);
	}

	ModResult OnStats(Stats::Context& stats) override
	{
		if (stats.GetSymbol() != 'S')
			return MOD_RES_PASSTHRU;

		ServerInstance->XLines->InvokeStats("SVSHOLD", stats);
		return MOD_RES_DENY;
	}

	ModResult OnUserPreNick(LocalUser* user, const std::string& newnick) override
	{
		XLine *rl = ServerInstance->XLines->MatchesLine("SVSHOLD", newnick);

		if (rl)
		{
			user->WriteNumeric(ERR_ERRONEUSNICKNAME, newnick, INSP_FORMAT("Services reserved nickname: {}", rl->reason));
			return MOD_RES_DENY;
		}

		return MOD_RES_PASSTHRU;
	}

	~ModuleSVSHold() override
	{
		ServerInstance->XLines->DelAll("SVSHOLD");
		ServerInstance->XLines->UnregisterFactory(&s);
	}
};

MODULE_INIT(ModuleSVSHold)