/*       +------------------------------------+
 *       | Inspire Internet Relay Chat Daemon |
 *       +------------------------------------+
 *
 *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
 * See: http://www.inspircd.org/wiki/index.php/Credits
 *
 * This program is free but copyrighted software; see
 *	  the file COPYING for details.
 *
 * ---------------------------------------------------
 */

/* $ModDesc: Provides a spanning tree server link protocol */

#include "inspircd.h"
#include "wildcard.h"

#include "m_spanningtree/main.h"
#include "m_spanningtree/utils.h"
#include "m_spanningtree/treeserver.h"
#include "m_spanningtree/treesocket.h"

/* $ModDep: m_spanningtree/main.h m_spanningtree/utils.h m_spanningtree/treeserver.h m_spanningtree/treesocket.h */

const std::string ModuleSpanningTree::MapOperInfo(TreeServer* Current)
{
	time_t secs_up = ServerInstance->Time() - Current->age;
	return (" [Up: " + TimeToStr(secs_up) + " Lag: " + (Current->rtt == 0 ? "<1" : ConvToStr(Current->rtt)) + "ms]");
}

// WARNING: NOT THREAD SAFE - DONT GET ANY SMART IDEAS.
void ModuleSpanningTree::ShowMap(TreeServer* Current, User* user, int depth, char matrix[250][250], float &totusers, float &totservers)
{
	ServerInstance->Logs->Log("map",DEBUG,"ShowMap depth %d totusers %0.2f totservers %0.2f", depth, totusers, totservers);
	if (line < 250)
	{
		for (int t = 0; t < depth; t++)
		{
			matrix[line][t] = ' ';
		}

		// For Aligning, we need to work out exactly how deep this thing is, and produce
		// a 'Spacer' String to compensate.
		char spacer[80];
		memset(spacer,' ',sizeof(spacer));
		if ((80 - Current->GetName().length() - depth) > 1) {
			spacer[80 - Current->GetName().length() - depth] = '\0';
		}
		else
		{
			spacer[5] = '\0';
		}

		float percent;
		char text[250];
		/* Neat and tidy default values, as we're dealing with a matrix not a simple string */
		memset(text, 0, sizeof(text));

		if (ServerInstance->Users->clientlist->size() == 0)
		{
			// If there are no users, WHO THE HELL DID THE /MAP?!?!?!
			percent = 0;
		}
		else
		{
			percent = ((float)Current->GetUserCount() / (float)ServerInstance->Users->clientlist->size()) * 100;
		}

		const std::string operdata = IS_OPER(user) ? MapOperInfo(Current) : "";
		snprintf(text, 249, "%s (%s)%s%5d [%5.2f%%]%s", Current->GetName().c_str(), Current->GetID().c_str(), spacer, Current->GetUserCount(), percent, operdata.c_str());
		totusers += Current->GetUserCount();
		totservers++;
		strlcpy(&matrix[line][depth], text, 249);
		line++;

		for (unsigned int q = 0; q < Current->ChildCount(); q++)
		{
			if ((Current->GetChild(q)->Hidden) || ((Utils->HideULines) && (ServerInstance->ULine(Current->GetChild(q)->GetName().c_str()))))
			{
				if (IS_OPER(user))
				{
					ShowMap(Current->GetChild(q),user,(Utils->FlatLinks && (!IS_OPER(user))) ? depth : depth+2,matrix,totusers,totservers);
				}
			}
			else
			{
				ShowMap(Current->GetChild(q),user,(Utils->FlatLinks && (!IS_OPER(user))) ? depth : depth+2,matrix,totusers,totservers);
			}
		}
	}
}


// Ok, prepare to be confused.
// After much mulling over how to approach this, it struck me that
// the 'usual' way of doing a /MAP isnt the best way. Instead of
// keeping track of a ton of ascii characters, and line by line
// under recursion working out where to place them using multiplications
// and divisons, we instead render the map onto a backplane of characters
// (a character matrix), then draw the branches as a series of "L" shapes
// from the nodes. This is not only friendlier on CPU it uses less stack.
int ModuleSpanningTree::HandleMap(const std::vector<std::string>& parameters, User* user)
{
	if (parameters.size() > 0)
	{
		/* Remote MAP, the server is within the 1st parameter */
		TreeServer* s = Utils->FindServerMask(parameters[0]);
		bool ret = false;
		if (!s)
		{
			user->WriteNumeric(ERR_NOSUCHSERVER, "%s %s :No such server", user->nick.c_str(), parameters[0].c_str());
			ret = true;
		}
		else if (s && s != Utils->TreeRoot)
		{
			std::deque<std::string> params;
			params.push_back(parameters[0]);

			params[0] = s->GetName();
			Utils->DoOneToOne(user->uuid, "MAP", params, s->GetName());
			ret = true;
		}

		// Don't return if s == Utils->TreeRoot (us)
		if (ret)
			return 1;
	}

	// This array represents a virtual screen which we will
	// "scratch" draw to, as the console device of an irc
	// client does not provide for a proper terminal.
	float totusers = 0;
	float totservers = 0;
	static char matrix[250][250];

	for (unsigned int t = 0; t < 250; t++)
	{
		matrix[t][0] = '\0';
	}

	line = 0;

	// The only recursive bit is called here.
	ShowMap(Utils->TreeRoot,user,0,matrix,totusers,totservers);

	// Process each line one by one. The algorithm has a limit of
	// 250 servers (which is far more than a spanning tree should have
	// anyway, so we're ok). This limit can be raised simply by making
	// the character matrix deeper, 250 rows taking 100k of memory.
	for (int l = 1; l < line; l++)
	{
		// scan across the line looking for the start of the
		// servername (the recursive part of the algorithm has placed
		// the servers at indented positions depending on what they
		// are related to)
		int first_nonspace = 0;

		while (matrix[l][first_nonspace] == ' ')
		{
			first_nonspace++;
		}

		first_nonspace--;

		// Draw the `- (corner) section: this may be overwritten by
		// another L shape passing along the same vertical pane, becoming
		// a |- (branch) section instead.

		matrix[l][first_nonspace] = '-';
		matrix[l][first_nonspace-1] = '`';
		int l2 = l - 1;

		// Draw upwards until we hit the parent server, causing possibly
		// other corners (`-) to become branches (|-)
		while ((matrix[l2][first_nonspace-1] == ' ') || (matrix[l2][first_nonspace-1] == '`'))
		{
			matrix[l2][first_nonspace-1] = '|';
			l2--;
		}
	}

	float avg_users = totusers / totservers;

	// dump the whole lot to the user.
	if (IS_LOCAL(user))
	{
		ServerInstance->Logs->Log("map",DEBUG,"local");
		for (int t = 0; t < line; t++)
		{
			user->WriteNumeric(RPL_MAP, "%s :%s",user->nick.c_str(),&matrix[t][0]);
		}
		user->WriteNumeric(RPL_MAPUSERS, "%s :%.0f server%s and %.0f user%s, average %.2f users per server",user->nick.c_str(),totservers,(totservers > 1 ? "s" : ""),totusers,(totusers > 1 ? "s" : ""),avg_users);
		user->WriteNumeric(RPL_ENDMAP, "%s :End of /MAP",user->nick.c_str());
	}
	else
	{
		ServerInstance->Logs->Log("map", DEBUG, "remote dump lines=%d", line);

		// XXX: annoying that we have to use hardcoded numerics here..
		for (int t = 0; t < line; t++)
		{
			ServerInstance->PI->PushToClient(user, std::string("::") + ServerInstance->Config->ServerName + " 006 " + user->nick + " :" + &matrix[t][0]);
		}

		ServerInstance->PI->PushToClient(user, std::string("::") + ServerInstance->Config->ServerName + " 270 " + user->nick + " :" + ConvToStr(totservers) + " server"+(totservers > 1 ? "s" : "") + " and " + ConvToStr(totusers) + " user"+(totusers > 1 ? "s" : "") + ", average " + ConvToStr(avg_users) + " users per server");
		ServerInstance->PI->PushToClient(user, std::string("::") + ServerInstance->Config->ServerName + " 007 " + user->nick + " :End of /MAP");
	}

	return 1;
}