#include "module.h"
#define FILENAME "seen.db" // TODO: read it from config
#define PURGETIME 15552000 // 180 days - TODO: read from config, "180d" or "6M"

enum TypeInfo
{
	NEW,
	NICK_TO,
	NICK_FROM,
	JOIN,
	PART,
	QUIT,
	KICK
};

struct SeenInfo
{
	Mutex mutex;
	Anope::string vhost;    // realhost, only for admins
	TypeInfo type;
	Anope::string nick2;    // only for nickchanges
	Anope::string channel;  // for join/part/kick
	Anope::string message;  // for part/kick/quit
	time_t last;            // the time when the user was last seen
};

typedef std::map<Anope::string, SeenInfo *, std::less<ci::string> > database_map;
database_map database;
Mutex database_mutex;

SeenInfo *FindInfo(const Anope::string &nick)
{
	database_mutex.Lock();
	database_map::iterator iter = database.find(nick);
	if (iter != database.end())
	{
		database_mutex.Unlock();
		return iter->second;
	}
	else
	{
		database_mutex.Unlock();
		return NULL;
	}
}

class UpdateThread : public Thread
{
 private:
	TypeInfo Type;
	Anope::string Nick, Nick2, Channel, Message, Vhost;
 public:
	UpdateThread(const User *u, const TypeInfo type, const Anope::string &nick, const Anope::string &nick2, const Anope::string &channel, const Anope::string &message)
		: Thread(), Type(type), Nick(nick), Nick2(nick2), Channel(channel), Message(message)
	{
		Vhost = u->GetVIdent() + "@" + u->GetDisplayedHost();
	}
	~UpdateThread() { }
	void Run()
	{
		SeenInfo *info = FindInfo(Nick);
		if (!info)
		{
			info = new SeenInfo;
			database_mutex.Lock();
			database.insert(std::pair<Anope::string, SeenInfo *>(Nick, info));
			database_mutex.Unlock();
		}
		Log() << "Thread: " << this->Handle << " locked mutex for " << Nick;
		info->mutex.Lock();
		info->vhost = Vhost;
		info->type = Type;
		info->last = Anope::CurTime;
		info->nick2 = Nick2;
		info->channel = Channel;
		info->message = Message;
		info->mutex.Unlock();
		Log() << "Thread: " << this->Handle << " unlocked mutex for " << Nick;

	}
};

class SaveDBThread : public Thread, public Mutex
{
 private:
	Anope::string Filename;
	bool dbproblem;

 public:
	SaveDBThread(const Anope::string &filename, bool nothread) : Thread(), Filename(filename)
	{
		dbproblem = false;
		if (nothread)
			this->Run();
	 }
	~SaveDBThread()
	{
		if (dbproblem)
			ircdproto->SendGlobops(NULL, "Unable to open %s for writing.", Filename.c_str());
	}
	void Run()
	{
		this->Lock(); // make sure we are not having 2 threads running at the same time.
		std::stringstream db_buffer;
		database_mutex.Lock();
		for (database_map::iterator it = database.begin(), it_end = database.end(); it != it_end; ++it)
		{
			it->second->mutex.Lock();
			db_buffer << it->first.c_str() << " " << it->second->vhost << " " << it->second->last << " ";
			switch (it->second->type)
			{
				case NEW:
					db_buffer << "NEW"; break;
				case NICK_TO:
					db_buffer << "NICK_TO " << it->second->nick2; break;
				case NICK_FROM:
					db_buffer << "NICK_FROM " << it->second->nick2; break;
				case JOIN:
					db_buffer << "JOIN " << it->second->channel; break;
				case PART:
					db_buffer << "PART " << it->second->channel << " :" << it->second->message; break;
				case QUIT:
					db_buffer << "QUIT :" << it->second->message; break;
				case KICK:
					db_buffer << "KICK " << it->second->nick2 << " " << it->second->channel << " :" << it->second->message; break;
			}
			it->second->mutex.Unlock();
			db_buffer << std::endl;
		}
		database_mutex.Unlock();
		std::fstream db;
		db.open(Filename.c_str(), std::ios_base::out | std::ios_base::trunc);
		if (!db.is_open())
		{
			dbproblem = true;
		}
		else 
		{
			db << db_buffer.str();
			db_buffer.str("");
			db.close();
		}
		this->Unlock();
	}
};

class PurgeDBThread : public Thread
{
 private:
	time_t Time;
 public:
	PurgeDBThread(const time_t time) : Thread(), Time(time) { }
	~PurgeDBThread() { }
	void Run()
	{
		// remove old entries from the database
	}
};

class CommandCSSeen : public Command
{
 public:
	CommandCSSeen() : Command("SEEN", 2, 3)
	{
		this->SetDesc("Makes the Bot say when a given User was last seen by services.");
	}

	CommandReturn Execute(CommandSource &source, const std::vector<Anope::string> &params)
	{
		const Anope::string &target = params[1];
		Anope::string onlinestatus;
		User *u = source.u, *u2 = NULL;
		ChannelInfo *ci = source.ci;

		if (!check_access(u, ci, CA_FANTASIA))
		{
			source.Reply(_(ACCESS_DENIED));
			return MOD_CONT;
		}

		if (!ci->bi)
		{
			source.Reply(_(BOT_NOT_ASSIGNED));
			return MOD_CONT;
		}

		if (!ci->c || !ci->c->FindUser(ci->bi))
		{
			source.Reply(_(BOT_NOT_ON_CHANNEL), ci->name.c_str());
			return MOD_CONT;
		}

		if (target.length() > Config->NickLen)
		{
			source.Reply(_("Nick too long, max length is %u chars"), Config->NickLen);
			return MOD_CONT;
		}
		if (target.equals_ci(ci->bi->nick))
		{
			source.Reply(_("You found me, %s"), u->nick.c_str());
			return MOD_CONT;
		}
		if (target.equals_ci(u->nick))
		{
			source.Reply(_("You might see yourself in the mirror, %s."), u->nick.c_str());
			return MOD_CONT;
		}
		SeenInfo *info = FindInfo(target);
		if (!info)
		{
			source.Reply(_("Sorry, I have not seen %s."), target.c_str());
			return MOD_CONT;
		}
		info->mutex.Lock();
		if ((u2 = finduser(target.c_str())))
			onlinestatus = ".";
		else
		{
			onlinestatus = Anope::printf(GetString(u->Account(), _(" but %s mysteriously dematerialized.")).c_str(), target.c_str());
		}

		struct tm *lastbuf;
		size_t tbuf, days, hours, minutes, seconds = 0;
		Anope::string timebuf, timebuf2;
		tbuf = (Anope::CurTime - info->last);
		days = (tbuf / 86400);
		hours = (tbuf / 3600) % 24;
		minutes = (tbuf / 60) % 60;
		seconds = (tbuf) % 60;
		lastbuf = localtime(&info->last);
		if (days)
			timebuf = Anope::printf(GetString(u->Account(), _("%u days, %u hours and %u minutes")).c_str(), days, hours, minutes);
		else if (hours)
			timebuf = Anope::printf(GetString(u->Account(), _("%u hours and %u minutes")).c_str(), hours, minutes);
		else if (minutes)
			timebuf = Anope::printf(GetString(u->Account(), _("%u minutes")).c_str(), minutes);
		else
			timebuf = Anope::printf(GetString(u->Account(), _("%u seconds")).c_str(), seconds);
		timebuf2 = do_strftime(info->last);

		if (info->type == NEW)
		{
			source.Reply(_("%s (%s) was last seen connecting %s ago (%s)%s"), 
				target.c_str(), info->vhost.c_str(), timebuf.c_str(), timebuf2.c_str(), onlinestatus.c_str());
		}
		else if (info->type == NICK_TO)
		{
			if ((u2 = finduser(info->nick2)))
				onlinestatus = Anope::printf(GetString(u->Account(),_(". %s is still online.")).c_str(), u2->nick.c_str());
			else
				onlinestatus = Anope::printf(GetString(u->Account(),_(", but %s mysteriously dematerialized")).c_str(), info->nick2.c_str());

			source.Reply(_("%s (%s) was last seen changing nick to %s %s ago%s"),
				target.c_str(), info->vhost.c_str(), info->nick2.c_str(), timebuf.c_str(), onlinestatus.c_str());
		}
		else if (info->type == NICK_FROM)
		{
			source.Reply(_("%s (%s) was last seen changing nick from %s to %s %s ago%s"), 
				target.c_str(), info->vhost.c_str(), info->nick2.c_str(), target.c_str(), timebuf.c_str(), onlinestatus.c_str());
		}
		else if (info->type == JOIN)
		{
			Channel *targetchan = findchan(info->channel);
			if (targetchan && (ci->c != targetchan) && targetchan->HasMode(CMODE_SECRET))
			{
				source.Reply(_("%s (%s) was last seen joining a secret channel %s ago%s"),
					target.c_str(), info->vhost.c_str(), timebuf.c_str(), onlinestatus.c_str());
			}
			else
			{
				source.Reply(_("%s (%s) was last seen joining %s %s ago%s"),
					target.c_str(), info->vhost.c_str(), info->channel.c_str(), timebuf.c_str(), onlinestatus.c_str());
			}
		}
		else if (info->type == PART)
		{
			Channel *targetchan = findchan(info->channel);
			if (targetchan && (ci->c != targetchan) && targetchan->HasMode(CMODE_SECRET))
			{
				source.Reply(_("%s (%s) was last seen parting a secret channel %s ago%s"),
					target.c_str(), info->vhost.c_str(), timebuf.c_str(), onlinestatus.c_str());
			}
			else
			{
				source.Reply(_("%s (%s) was last seen parting %s %s ago%s"),
					target.c_str(), info->vhost.c_str(), info->channel.c_str(), timebuf.c_str(), onlinestatus.c_str());
			}
		}
		else if (info->type == QUIT)
		{
			source.Reply(_("%s (%s) was last seen quitting (%s) %s ago (%s)."),
					target.c_str(), info->vhost.c_str(), info->message.c_str(), timebuf.c_str(), timebuf2.c_str());
		}
		else if (info->type == KICK)
		{
			Channel *targetchan = findchan(info->channel);
			if (targetchan && (ci->c != targetchan) && targetchan->HasMode(CMODE_SECRET))
			{
				source.Reply(_("%s (%s) was kicked from a secret channel %s ago%s"),
					target.c_str(), info->vhost.c_str(), timebuf.c_str(), onlinestatus.c_str());
			}
			else
			{
				source.Reply(_("%s (%s) was kicked from %s (\"%s\") %s ago%s"),
					target.c_str(), info->vhost.c_str(), info->channel.c_str(), info->message.c_str(), timebuf.c_str(), onlinestatus.c_str());
			}
		}
		info->mutex.Unlock(); // never ever return without Unlock()!
		return MOD_CONT;
	}

	void OnSyntaxError(CommandSource &source, const Anope::string &subcommand)
	{
		SyntaxError(source, "SEEN", _("SEEN \037channel\037 \037nick\037"));
	}
};


class BSSeen : public Module
{
	CommandCSSeen commandcsseen;
 public:
	BSSeen(const Anope::string &modname, const Anope::string &creator) : Module(modname, creator)
	{
		Implementation eventlist[] =  { I_OnUserConnect,
						I_OnUserNickChange,
						I_OnUserQuit,
						I_OnJoinChannel,
						I_OnPartChannel,
						I_OnUserKicked,
						I_OnSaveDatabase,
						I_OnDatabaseExpire };
		ModuleManager::Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
		this->SetAuthor("Anope");
		this->SetType(SUPPORTED);
		AddCommand(ChanServ, &commandcsseen);
		LoadDatabase(FILENAME);
	}
	~BSSeen()
	{
		SaveDBThread(FILENAME, true);
	}
	EventReturn OnSaveDatabase()
	{
		threadEngine.Start(new SaveDBThread(FILENAME, false));
		return EVENT_CONTINUE;
	}
	void OnDatabaseExpire()
	{
		threadEngine.Start(new PurgeDBThread(PURGETIME));
	}
	void OnUserConnect(User *u)
	{
		threadEngine.Start(new UpdateThread(u, NEW, u->nick, "", "", ""));
	}
	void OnUserNickChange(User *u, const Anope::string &oldnick)
	{
		threadEngine.Start(new UpdateThread(u, NICK_TO, oldnick, u->nick, "", ""));
		threadEngine.Start(new UpdateThread(u, NICK_FROM, u->nick, oldnick, "", ""));
	}
	void OnUserQuit(User *u, const Anope::string &msg)
	{
		threadEngine.Start(new UpdateThread(u, QUIT, u->nick, "", "", msg));
	}
	void OnJoinChannel(User *u, Channel *c)
	{
		threadEngine.Start(new UpdateThread(u, JOIN, u->nick, "", c->name, ""));
	}
	void OnPartChannel(User *u, Channel *c, const Anope::string &channel, const Anope::string &msg)
	{
		threadEngine.Start(new UpdateThread(u, PART, u->nick, "", channel, msg));
	}
	void OnUserKicked(Channel *c, User *target, const Anope::string &source, const Anope::string &msg)
	{
		threadEngine.Start(new UpdateThread(target, KICK, target->nick, source, c->name, msg));
	}
	void LoadDatabase(const Anope::string &Filename)
	{
		std::fstream db;
		db.open(Filename.c_str(), std::ios_base::in);
		if (!db.is_open())
		{
			Log() << "Unable to open " << Filename << " for reading.";
			return;
		}
		Anope::string buf;
		while (std::getline(db, buf.str()))
		{
			if (buf.empty())
				continue;
			spacesepstream sep(buf);
			std::vector<Anope::string> params;
			while (sep.GetToken(buf))
			{
				if (buf[0] == ':')
				{
					buf.erase(buf.begin());
					if (!buf.empty() && !sep.StreamEnd())
						params.push_back(buf + " " + sep.GetRemaining());
					else if (!sep.StreamEnd())
						params.push_back(sep.GetRemaining());
					else if (!buf.empty())
						params.push_back(buf);
					break;
				}
				else
					params.push_back(buf);
			}
			if (params.size() >= 4)
			{
				SeenInfo *info = new SeenInfo;
				database.insert(std::pair<Anope::string, SeenInfo *>(params[0], info));
				info->vhost = params[1];
				info->last = params[2].is_pos_number_only() ? convertTo<time_t>(params[2]) : 0 ;
				if (params[3].equals_ci("NEW"))
				{
					info->type = NEW;
				}
				else if (params[3].equals_ci("NICK_TO") && params.size() == 5)
				{
					info->type = NICK_TO;
					info->nick2 = params[4];
				}
				else if (params[3].equals_ci("NICK_FROM") && params.size() == 5)
				{
					info->type = NICK_FROM;
					info->nick2 = params[4];
				}
				else if (params[3].equals_ci("JOIN") && params.size() == 5)
				{
					info->type = JOIN;
					info->channel = params[4];
				}
				else if (params[3].equals_ci("PART") && params.size() == 6)
				{
					info->type = PART;
					info->channel = params[4];
					info->message = params[5];
				}
				else if (params[3].equals_ci("QUIT") && params.size() == 5)
				{
					info->type = QUIT;
					info->message = params[4];
				}
				else if (params[3].equals_ci("KICK") && params.size() == 7)
				{
					info->type = KICK;
					info->nick2 = params[4];
					info->channel = params[5];
					info->message = params[6];
				}
			} // if params.size()
		} // while getline
	} // LoadDatabase()
};

MODULE_INIT(BSSeen)