/* Mode support
 *
 * Copyright (C) 2008-2011 Adam <Adam@anope.org>
 * Copyright (C) 2008-2013 Anope Team <team@anope.org>
 *
 * Please read COPYING and README for further details.
 *
 */

#include "services.h"
#include "modules.h"
#include "config.h"
#include "sockets.h"
#include "protocol.h"
#include "channels.h"
#include "uplink.h"

struct StackerInfo;

/* List of pairs of user/channels and their stacker info */
static std::map<User *, StackerInfo *> UserStackerObjects;
static std::map<Channel *, StackerInfo *> ChannelStackerObjects;

/* List of all modes Anope knows about */
std::vector<ChannelMode *> ModeManager::ChannelModes;
std::vector<UserMode *> ModeManager::UserModes;

static std::map<Anope::string, ChannelMode *> ChannelModesByName;
static std::map<Anope::string, UserMode *> UserModesByName;

/* Sorted by status */
static std::vector<ChannelModeStatus *> ChannelModesByStatus;

/* Number of generic modes we support */
unsigned ModeManager::GenericChannelModes = 0, ModeManager::GenericUserModes = 0;

struct StackerInfo
{
	/* Modes to be added */
	std::list<std::pair<Mode *, Anope::string> > AddModes;
	/* Modes to be deleted */
	std::list<std::pair<Mode *, Anope::string> > DelModes;
	/* Bot this is sent from */
	BotInfo *bi;

	StackerInfo() : bi(NULL) { }

	/** Add a mode to this object
	 * @param mode The mode
	 * @param set true if setting, false if unsetting
	 * @param param The param for the mode
	 */
	void AddMode(Mode *mode, bool set, const Anope::string &param);
};

ChannelStatus::ChannelStatus()
{
}

ChannelStatus::ChannelStatus(const Anope::string &m) : modes(m)
{
}

void ChannelStatus::AddMode(char c)
{
	if (modes.find(c) == Anope::string::npos)
		modes.append(c);
}

void ChannelStatus::DelMode(char c)
{
	modes = modes.replace_all_cs(c, "");
}

bool ChannelStatus::HasMode(char c) const
{
	return modes.find(c) != Anope::string::npos;
}

bool ChannelStatus::Empty() const
{
	return modes.empty();
}

void ChannelStatus::Clear()
{
	modes.clear();
}

const Anope::string &ChannelStatus::Modes() const
{
	return modes;
}

Anope::string ChannelStatus::BuildModePrefixList() const
{
	Anope::string ret;

	for (size_t i = 0; i < modes.length(); ++i)
	{
		ChannelMode *cm = ModeManager::FindChannelModeByChar(modes[i]);
		if (cm != NULL && cm->type == MODE_STATUS)
		{
			ChannelModeStatus *cms = anope_dynamic_static_cast<ChannelModeStatus *>(cm);
			ret += cms->symbol;
		}
	}

	return ret;
}

Mode::Mode(const Anope::string &mname, ModeClass mcl, char mch, ModeType mt) : name(mname), mclass(mcl), mchar(mch), type(mt)
{
}

Mode::~Mode()
{
}

bool Mode::CanSet(User *u) const
{
	return true;
}

UserMode::UserMode(const Anope::string &un, char mch) : Mode(un, MC_USER, mch, MODE_REGULAR)
{
}

UserModeParam::UserModeParam(const Anope::string &un, char mch) : UserMode(un, mch)
{
	this->type = MODE_PARAM;
}

ChannelMode::ChannelMode(const Anope::string &cm, char mch) : Mode(cm, MC_CHANNEL, mch, MODE_REGULAR)
{
}

bool ChannelMode::CanSet(User *u) const
{
	EventReturn MOD_RESULT;
	FOREACH_RESULT(OnCanSet, MOD_RESULT, (u, this));
	return MOD_RESULT != EVENT_STOP;
}

ChannelModeList::ChannelModeList(const Anope::string &cm, char mch) : ChannelMode(cm, mch)
{
	this->type = MODE_LIST;
}

ChannelModeParam::ChannelModeParam(const Anope::string &cm, char mch, bool ma) : ChannelMode(cm, mch), minus_no_arg(ma)
{
	this->type = MODE_PARAM;
}

ChannelModeStatus::ChannelModeStatus(const Anope::string &mname, char modeChar, char msymbol, short mlevel) : ChannelMode(mname, modeChar), symbol(msymbol), level(mlevel)
{
	this->type = MODE_STATUS;
}

bool UserModeOperOnly::CanSet(User *u) const
{
	return u && u->HasMode("OPER");
}

bool UserModeNoone::CanSet(User *u) const
{
	return false;
}

bool ChannelModeKey::IsValid(const Anope::string &value) const
{
	if (!value.empty() && value.find(':') == Anope::string::npos && value.find(',') == Anope::string::npos)
		return true;

	return false;
}

bool ChannelModeOperOnly::CanSet(User *u) const
{
	return u && u->HasMode("OPER");
}

bool ChannelModeNoone::CanSet(User *u) const
{
	return false;
}

void StackerInfo::AddMode(Mode *mode, bool set, const Anope::string &param)
{
	bool is_param = mode->type == MODE_PARAM;

	std::list<std::pair<Mode *, Anope::string> > *list, *otherlist;
	if (set)
	{
		list = &AddModes;
		otherlist = &DelModes;
	}
	else
	{
		list = &DelModes;
		otherlist = &AddModes;
	}

	/* Loop through the list and find if this mode is already on here */
	std::list<std::pair<Mode *, Anope::string > >::iterator it, it_end;
	for (it = list->begin(), it_end = list->end(); it != it_end; ++it)
	{
		/* The param must match too (can have multiple status or list modes), but
		 * if it is a param mode it can match no matter what the param is
		 */
		if (it->first == mode && (is_param || param.equals_cs(it->second)))
		{
			list->erase(it);
			/* It can only be on this list once */
			break;
		}
	}
	/* If the mode is on the other list, remove it from there (eg, we dont want +o-o Adam Adam) */
	for (it = otherlist->begin(), it_end = otherlist->end(); it != it_end; ++it)
	{
		/* The param must match too (can have multiple status or list modes), but
		 * if it is a param mode it can match no matter what the param is
		 */
		if (it->first == mode && (is_param || param.equals_cs(it->second)))
		{
			otherlist->erase(it);
			return;
			/* Note that we return here because this is like setting + and - on the same mode within the same
			 * cycle, no change is made. This causes no problems with something like - + and -, because after the
			 * second mode change the list is empty, and the third mode change starts fresh.
			 */
		}
	}

	/* Add this mode and its param to our list */
	list->push_back(std::make_pair(mode, param));
}

static class ModePipe : public Pipe
{
 public:
	void OnNotify()
	{
		ModeManager::ProcessModes();
	}
} *modePipe;

/** Get the stacker info for an item, if one doesnt exist it is created
 * @param Item The user/channel etc
 * @return The stacker info
 */
template<typename List, typename Object>
static StackerInfo *GetInfo(List &l, Object *o)
{
	typename List::const_iterator it = l.find(o);
	if (it != l.end())
		return it->second;

	StackerInfo *s = new StackerInfo();
	l[o] = s;
	return s;
}

/** Build a list of mode strings to send to the IRCd from the mode stacker
 * @param info The stacker info for a channel or user
 * @return a list of strings
 */
static std::list<Anope::string> BuildModeStrings(StackerInfo *info)
{
	std::list<Anope::string> ret;
	std::list<std::pair<Mode *, Anope::string> >::iterator it, it_end;
	Anope::string buf = "+", parambuf;
	unsigned NModes = 0;

	for (it = info->AddModes.begin(), it_end = info->AddModes.end(); it != it_end; ++it)
	{
		if (++NModes > IRCD->MaxModes || (buf.length() + parambuf.length() > IRCD->MaxLine - 100)) // Leave room for command, channel, etc
		{
			ret.push_back(buf + parambuf);
			buf = "+";
			parambuf.clear();
			NModes = 1;
		}

		buf += it->first->mchar;

		if (!it->second.empty())
			parambuf += " " + it->second;
	}

	if (buf[buf.length() - 1] == '+')
		buf.erase(buf.length() - 1);

	buf += "-";
	for (it = info->DelModes.begin(), it_end = info->DelModes.end(); it != it_end; ++it)
	{
		if (++NModes > IRCD->MaxModes || (buf.length() + parambuf.length() > IRCD->MaxLine - 100)) // Leave room for command, channel, etc
		{
			ret.push_back(buf + parambuf);
			buf = "-";
			parambuf.clear();
			NModes = 1;
		}

		buf += it->first->mchar;

		if (!it->second.empty())
			parambuf += " " + it->second;
	}

	if (buf[buf.length() - 1] == '-')
		buf.erase(buf.length() - 1);

	if (!buf.empty())
		ret.push_back(buf + parambuf);

	return ret;
}

bool ModeManager::AddUserMode(UserMode *um)
{
	if (ModeManager::FindUserModeByChar(um->mchar) != NULL)
		return false;
	
	if (um->name.empty())
	{
		um->name = stringify(++GenericUserModes);
		Log() << "ModeManager: Added generic support for user mode " << um->mchar;
	}

	unsigned want = um->mchar;
	if (want >= ModeManager::UserModes.size())
		ModeManager::UserModes.resize(want + 1);
	ModeManager::UserModes[want] = um;

	UserModesByName[um->name] = um;

	FOREACH_MOD(OnUserModeAdd, (um));

	return true;
}

bool ModeManager::AddChannelMode(ChannelMode *cm)
{
	if (ModeManager::FindChannelModeByChar(cm->mchar) != NULL)
		return false;

	if (cm->name.empty())
	{
		cm->name = stringify(++GenericChannelModes);
		Log() << "ModeManager: Added generic support for channel mode " << cm->mchar;
	}

	unsigned want = cm->mchar;
	if (want >= ModeManager::ChannelModes.size())
		ModeManager::ChannelModes.resize(want + 1);
	ModeManager::ChannelModes[want] = cm;

	if (cm->type == MODE_STATUS)
	{
		ChannelModeStatus *cms = anope_dynamic_static_cast<ChannelModeStatus *>(cm);
		want = cms->symbol;
		if (want >= ModeManager::ChannelModes.size())
			ModeManager::ChannelModes.resize(want + 1);
		ModeManager::ChannelModes[want] = cms;

		RebuildStatusModes();
	}

	ChannelModesByName[cm->name] = cm;

	FOREACH_MOD(OnChannelModeAdd, (cm));

	return true;
}

void ModeManager::RemoveUserMode(UserMode *um)
{
	if (!um)
		return;
	
	unsigned want = um->mchar;
	if (want >= ModeManager::UserModes.size())
		return;
	
	if (ModeManager::UserModes[want] != um)
		return;
	
	ModeManager::UserModes[want] = NULL;

	UserModesByName.erase(um->name);

	StackerDel(um);
}

void ModeManager::RemoveChannelMode(ChannelMode *cm)
{
	if (!cm)
		return;
	
	unsigned want = cm->mchar;
	if (want >= ModeManager::ChannelModes.size())
		return;
	
	if (ModeManager::ChannelModes[want] != cm)
		return;
	
	ModeManager::ChannelModes[want] = NULL;

	if (cm->type == MODE_STATUS)
	{
		ChannelModeStatus *cms = anope_dynamic_static_cast<ChannelModeStatus *>(cm);
		want = cms->symbol;

		if (want >= ModeManager::ChannelModes.size())
			return;

		if (ModeManager::ChannelModes[want] != cm)
			return;

		ModeManager::ChannelModes[want] = NULL;

		RebuildStatusModes();
	}

	ChannelModesByName.erase(cm->name);

	StackerDel(cm);
}

ChannelMode *ModeManager::FindChannelModeByChar(char mode)
{
	unsigned want = mode;
	if (want >= ModeManager::ChannelModes.size())
		return NULL;
	
	return ModeManager::ChannelModes[want];
}

UserMode *ModeManager::FindUserModeByChar(char mode)
{
	unsigned want = mode;
	if (want >= ModeManager::UserModes.size())
		return NULL;
	
	return ModeManager::UserModes[want];
}

ChannelMode *ModeManager::FindChannelModeByName(const Anope::string &name)
{
	std::map<Anope::string, ChannelMode *>::iterator it = ChannelModesByName.find(name);
	if (it != ChannelModesByName.end())
		return it->second;
	return NULL;
}

UserMode *ModeManager::FindUserModeByName(const Anope::string &name)
{
	std::map<Anope::string, UserMode *>::iterator it = UserModesByName.find(name);
	if (it != UserModesByName.end())
		return it->second;
	return NULL;
}

char ModeManager::GetStatusChar(char value)
{
	unsigned want = value;
	if (want >= ModeManager::ChannelModes.size())
		return 0;
	
	ChannelMode *cm = ModeManager::ChannelModes[want];
	if (cm == NULL || cm->type != MODE_STATUS || cm->mchar == value)
		return 0;
	
	return cm->mchar;
}

const std::vector<ChannelMode *> &ModeManager::GetChannelModes()
{
	return ChannelModes;
}

const std::vector<UserMode *> &ModeManager::GetUserModes()
{
	return UserModes;
}

const std::vector<ChannelModeStatus *> &ModeManager::GetStatusChannelModesByRank()
{
	return ChannelModesByStatus;
}

static struct StatusSort
{
	bool operator()(ChannelModeStatus *cm1, ChannelModeStatus *cm2) const
	{
		return cm1->level > cm2->level;
	}
} statuscmp;

void ModeManager::RebuildStatusModes()
{
	ChannelModesByStatus.clear();
	for (unsigned j = 0; j < ModeManager::GetChannelModes().size(); ++j)
	{
		ChannelMode *cm = ModeManager::GetChannelModes()[j];

		if (cm && cm->type == MODE_STATUS && std::find(ChannelModesByStatus.begin(), ChannelModesByStatus.end(), cm) == ChannelModesByStatus.end())
			ChannelModesByStatus.push_back(anope_dynamic_static_cast<ChannelModeStatus *>(cm));
	}
	std::sort(ChannelModesByStatus.begin(), ChannelModesByStatus.end(), statuscmp);
}

void ModeManager::StackerAdd(BotInfo *bi, Channel *c, ChannelMode *cm, bool Set, const Anope::string &Param)
{
	StackerInfo *s = GetInfo(ChannelStackerObjects, c);
	s->AddMode(cm, Set, Param);
	if (bi)
		s->bi = bi;
	else
		s->bi = c->ci->WhoSends();

	if (!modePipe)
		modePipe = new ModePipe();
	modePipe->Notify();
}

void ModeManager::StackerAdd(BotInfo *bi, User *u, UserMode *um, bool Set, const Anope::string &Param)
{
	StackerInfo *s = GetInfo(UserStackerObjects, u);
	s->AddMode(um, Set, Param);
	if (bi)
		s->bi = bi;

	if (!modePipe)
		modePipe = new ModePipe();
	modePipe->Notify();
}

void ModeManager::ProcessModes()
{
	if (!UserStackerObjects.empty())
	{
		for (std::map<User *, StackerInfo *>::const_iterator it = UserStackerObjects.begin(), it_end = UserStackerObjects.end(); it != it_end; ++it)
		{
			User *u = it->first;
			StackerInfo *s = it->second;

			std::list<Anope::string> ModeStrings = BuildModeStrings(s);
			for (std::list<Anope::string>::iterator lit = ModeStrings.begin(), lit_end = ModeStrings.end(); lit != lit_end; ++lit)
				IRCD->SendMode(s->bi, u, lit->c_str());
			delete it->second;
		}
		UserStackerObjects.clear();
	}

	if (!ChannelStackerObjects.empty())
	{
		for (std::map<Channel *, StackerInfo *>::const_iterator it = ChannelStackerObjects.begin(), it_end = ChannelStackerObjects.end(); it != it_end; ++it)
		{
			Channel *c = it->first;
			StackerInfo *s = it->second;

			std::list<Anope::string> ModeStrings = BuildModeStrings(s);
			for (std::list<Anope::string>::iterator lit = ModeStrings.begin(), lit_end = ModeStrings.end(); lit != lit_end; ++lit)
				IRCD->SendMode(s->bi, c, lit->c_str());
			delete it->second;
		}
		ChannelStackerObjects.clear();
	}
}

void ModeManager::StackerDel(User *u)
{
	UserStackerObjects.erase(u);
}

void ModeManager::StackerDel(Channel *c)
{
	ChannelStackerObjects.erase(c);
}

void ModeManager::StackerDel(Mode *m)
{
	for (std::map<User *, StackerInfo *>::const_iterator it = UserStackerObjects.begin(), it_end = UserStackerObjects.end(); it != it_end;)
	{
		StackerInfo *si = it->second;
		++it;

		for (std::list<std::pair<Mode *, Anope::string> >::iterator it2 = si->AddModes.begin(), it2_end = si->AddModes.end(); it2 != it2_end;)
		{
			if (it2->first == m)
				it2 = si->AddModes.erase(it2);
			else
				++it2;
		}

		for (std::list<std::pair<Mode *, Anope::string> >::iterator it2 = si->DelModes.begin(), it2_end = si->DelModes.end(); it2 != it2_end;)
		{
			if (it2->first == m)
				it2 = si->DelModes.erase(it2);
			else
				++it2;
		}
	}

	for (std::map<Channel *, StackerInfo *>::const_iterator it = ChannelStackerObjects.begin(), it_end = ChannelStackerObjects.end(); it != it_end;)
	{
		StackerInfo *si = it->second;
		++it;

		for (std::list<std::pair<Mode *, Anope::string> >::iterator it2 = si->AddModes.begin(), it2_end = si->AddModes.end(); it2 != it2_end;)
		{
			if (it2->first == m)
				it2 = si->AddModes.erase(it2);
			else
				++it2;
		}

		for (std::list<std::pair<Mode *, Anope::string> >::iterator it2 = si->DelModes.begin(), it2_end = si->DelModes.end(); it2 != it2_end;)
		{
			if (it2->first == m)
				it2 = si->DelModes.erase(it2);
			else
				++it2;
		}
	}
}

Entry::Entry(const Anope::string &m, const Anope::string &fh) : name(m), mask(fh), cidr_len(0)
{
	Anope::string n, u, h;

	size_t at = fh.find('@');
	if (at != Anope::string::npos)
	{
		this->host = fh.substr(at + 1);

		const Anope::string &nu = fh.substr(0, at);

		size_t ex = nu.find('!');
		if (ex != Anope::string::npos)
		{
			this->user = nu.substr(ex + 1);
			this->nick = nu.substr(0, ex);
		}
		else
			this->user = nu;
	}
	else
	{
		if (fh.find('.') != Anope::string::npos || fh.find(':') != Anope::string::npos)
			this->host = fh;
		else
			this->nick = fh;
	}
	
	at = this->host.find('#');
	if (at != Anope::string::npos)
	{
		this->real = this->host.substr(at + 1);
		this->host = this->host.substr(0, at);
	}
	
	/* If the mask is all *'s it will match anything, so just clear it */
	if (this->nick.find_first_not_of("*") == Anope::string::npos)
		this->nick.clear();
	
	if (this->user.find_first_not_of("*") == Anope::string::npos)
		this->user.clear();
	
	if (this->host.find_first_not_of("*") == Anope::string::npos)
		this->host.clear();
	else
	{
		/* Host might be a CIDR range */
		size_t sl = this->host.find_last_of('/');
		if (sl != Anope::string::npos)
		{
			const Anope::string &cidr_ip = this->host.substr(0, sl),
						&cidr_range = this->host.substr(sl + 1);

			sockaddrs addr(cidr_ip);

			try
			{
				if (addr.valid() && cidr_range.is_pos_number_only())
				{
					this->cidr_len = convertTo<unsigned short>(cidr_range);
					/* If we got here, cidr_len is a valid number.
					 * If cidr_len is >32 (or 128) it is handled later in
					 * cidr::match
					 */

					this->host = cidr_ip;

					Log(LOG_DEBUG) << "Ban " << this->mask << " has cidr " << this->cidr_len;
				}
			}
			catch (const ConvertException &) { }
		}
	}

	if (this->real.find_first_not_of("*") == Anope::string::npos)
		this->real.clear();
}

const Anope::string Entry::GetMask() const
{
	return this->mask;
}

bool Entry::Matches(User *u, bool full) const
{
	/* First check if this mode has defined any matches (usually for extbans). */
	if (IRCD->IsExtbanValid(this->mask))
	{
		ChannelMode *cm = ModeManager::FindChannelModeByName(this->name);
		if (cm != NULL && cm->type == MODE_LIST)
		{
			ChannelModeList *cml = anope_dynamic_static_cast<ChannelModeList *>(cm);
			if (cml->Matches(u, this))
				return true;
		}
	}

	/* If the user's displayed host is their real host, then we can do a full match without
	 * having to worry about exposing a user's IP
	 */
	full |= u->GetDisplayedHost() == u->host;

	bool ret = true;

	if (!this->nick.empty() && !Anope::Match(u->nick, this->nick))
		ret = false;

	if (!this->user.empty() && !Anope::Match(u->GetVIdent(), this->user) && (!full || !Anope::Match(u->GetIdent(), this->user)))
		ret = false;

	if (this->cidr_len && full)
	{
		try
		{
			if (!cidr(this->host, this->cidr_len).match(u->ip))
				ret = false;
		}
		catch (const SocketException &)
		{
			ret = false;
		}
	}
	else if (!this->host.empty() && !Anope::Match(u->GetDisplayedHost(), this->host) && !Anope::Match(u->GetCloakedHost(), this->host) &&
		(!full || (!Anope::Match(u->host, this->host) && !Anope::Match(u->ip, this->host))))
		ret = false;
	
	if (!this->real.empty() && !Anope::Match(u->realname, this->real))
		ret = false;
	
	return ret;
}