/**
 * @file llcallingcard.cpp
 * @brief Implementation of the LLPreviewCallingCard class
 *
 * $LicenseInfo:firstyear=2002&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#include "llviewerprecompiledheaders.h"

#include "llcallingcard.h"

#include <algorithm>

#include "indra_constants.h"
#include "llstl.h"
#include "lltimer.h"
#include "lluuid.h"
#include "message.h"

#include "llagent.h"
#include "llavatarnamecache.h"
#include "llinventoryobserver.h"
#include "llinventorymodel.h"
#include "llnotifications.h"
#include "llslurl.h"
#include "llimview.h"
#include "lltrans.h"
#include "llviewercontrol.h"
#include "llviewerobjectlist.h"
#include "llvoavatar.h"
#include "llavataractions.h"
#include "lluiusage.h"

///----------------------------------------------------------------------------
/// Local function declarations, constants, enums, and typedefs
///----------------------------------------------------------------------------

class LLTrackingData
{
public:
    LLTrackingData(const LLUUID& avatar_id, const std::string& name);
    bool haveTrackingInfo();
    void setTrackedCoarseLocation(const LLVector3d& global_pos);
    void agentFound(const LLUUID& prey,
                    const LLVector3d& estimated_global_pos);

public:
    LLUUID mAvatarID;
    std::string mName;
    LLVector3d mGlobalPositionEstimate;
    bool mHaveInfo;
    bool mHaveCoarseInfo;
    LLTimer mCoarseLocationTimer;
    LLTimer mUpdateTimer;
    LLTimer mAgentGone;
};

const F32 COARSE_FREQUENCY = 2.2f;
const F32 FIND_FREQUENCY = 29.7f;   // This results in a database query, so cut these back
const F32 OFFLINE_SECONDS = FIND_FREQUENCY + 8.0f;

// static
LLAvatarTracker LLAvatarTracker::sInstance;

static void on_avatar_name_cache_notify(const LLUUID& agent_id,
                                        const LLAvatarName& av_name,
                                        bool online,
                                        LLSD payload);

///----------------------------------------------------------------------------
/// Class LLAvatarTracker
///----------------------------------------------------------------------------

LLAvatarTracker::LLAvatarTracker() :
    mTrackingData(NULL),
    mTrackedAgentValid(false),
    mModifyMask(0x0),
    mIsNotifyObservers(false)
{
}

LLAvatarTracker::~LLAvatarTracker()
{
    deleteTrackingData();
    std::for_each(mObservers.begin(), mObservers.end(), DeletePointer());
    mObservers.clear();
    std::for_each(mBuddyInfo.begin(), mBuddyInfo.end(), DeletePairedPointer());
    mBuddyInfo.clear();
}

void LLAvatarTracker::track(const LLUUID& avatar_id, const std::string& name)
{
    deleteTrackingData();
    mTrackedAgentValid = false;
    mTrackingData = new LLTrackingData(avatar_id, name);
    findAgent();

    // We track here because findAgent() is called on a timer (for now).
    if(avatar_id.notNull())
    {
        LLMessageSystem* msg = gMessageSystem;
        msg->newMessageFast(_PREHASH_TrackAgent);
        msg->nextBlockFast(_PREHASH_AgentData);
        msg->addUUIDFast(_PREHASH_AgentID, gAgent.getID());
        msg->addUUIDFast(_PREHASH_SessionID, gAgent.getSessionID());
        msg->nextBlockFast(_PREHASH_TargetData);
        msg->addUUIDFast(_PREHASH_PreyID, avatar_id);
        gAgent.sendReliableMessage();
    }
}

void LLAvatarTracker::untrack(const LLUUID& avatar_id)
{
    if (mTrackingData && mTrackingData->mAvatarID == avatar_id)
    {
        deleteTrackingData();
        mTrackedAgentValid = false;
        LLMessageSystem* msg = gMessageSystem;
        msg->newMessageFast(_PREHASH_TrackAgent);
        msg->nextBlockFast(_PREHASH_AgentData);
        msg->addUUIDFast(_PREHASH_AgentID, gAgent.getID());
        msg->addUUIDFast(_PREHASH_SessionID, gAgent.getSessionID());
        msg->nextBlockFast(_PREHASH_TargetData);
        msg->addUUIDFast(_PREHASH_PreyID, LLUUID::null);
        gAgent.sendReliableMessage();
    }
}

void LLAvatarTracker::setTrackedCoarseLocation(const LLVector3d& global_pos)
{
    if(mTrackingData)
    {
        mTrackingData->setTrackedCoarseLocation(global_pos);
    }
}

bool LLAvatarTracker::haveTrackingInfo()
{
    if(mTrackingData)
    {
        return mTrackingData->haveTrackingInfo();
    }
    return false;
}

LLVector3d LLAvatarTracker::getGlobalPos()
{
    if(!mTrackedAgentValid || !mTrackingData) return LLVector3d();
    LLVector3d global_pos;

    LLViewerObject* object = gObjectList.findObject(mTrackingData->mAvatarID);
    if(object && !object->isDead())
    {
        global_pos = object->getPositionGlobal();
        // HACK - for making the tracker point above the avatar's head
        // rather than its groin
        LLVOAvatar* av = (LLVOAvatar*)object;
        global_pos.mdV[VZ] += 0.7f * (av->mBodySize.mV[VZ] + av->mAvatarOffset.mV[VZ]);

        mTrackingData->mGlobalPositionEstimate = global_pos;
    }
    else
    {
        global_pos = mTrackingData->mGlobalPositionEstimate;
    }

    return global_pos;
}

void LLAvatarTracker::getDegreesAndDist(F32& rot,
                                        F64& horiz_dist,
                                        F64& vert_dist)
{
    if(!mTrackingData) return;

    LLVector3d global_pos;

    LLViewerObject* object = gObjectList.findObject(mTrackingData->mAvatarID);
    if(object && !object->isDead())
    {
        global_pos = object->getPositionGlobal();
        mTrackingData->mGlobalPositionEstimate = global_pos;
    }
    else
    {
        global_pos = mTrackingData->mGlobalPositionEstimate;
    }
    LLVector3d to_vec = global_pos - gAgent.getPositionGlobal();
    horiz_dist = sqrt(to_vec.mdV[VX] * to_vec.mdV[VX] + to_vec.mdV[VY] * to_vec.mdV[VY]);
    vert_dist = to_vec.mdV[VZ];
    rot = F32(RAD_TO_DEG * atan2(to_vec.mdV[VY], to_vec.mdV[VX]));
}

const std::string& LLAvatarTracker::getName()
{
    if(mTrackingData)
    {
        return mTrackingData->mName;
    }
    else
    {
        return LLStringUtil::null;
    }
}

const LLUUID& LLAvatarTracker::getAvatarID()
{
    if(mTrackingData)
    {
        return mTrackingData->mAvatarID;
    }
    else
    {
        return LLUUID::null;
    }
}

S32 LLAvatarTracker::addBuddyList(const LLAvatarTracker::buddy_map_t& buds)
{
    using namespace std;

    U32 new_buddy_count = 0;
    LLUUID agent_id;
    for(buddy_map_t::const_iterator itr = buds.begin(); itr != buds.end(); ++itr)
    {
        agent_id = (*itr).first;
        buddy_map_t::const_iterator existing_buddy = mBuddyInfo.find(agent_id);
        if(existing_buddy == mBuddyInfo.end())
        {
            ++new_buddy_count;
            mBuddyInfo[agent_id] = (*itr).second;

            // pre-request name for notifications?
            LLAvatarName av_name;
            LLAvatarNameCache::get(agent_id, &av_name);

            addChangedMask(LLFriendObserver::ADD, agent_id);
            LL_DEBUGS() << "Added buddy " << agent_id
                    << ", " << (mBuddyInfo[agent_id]->isOnline() ? "Online" : "Offline")
                    << ", TO: " << mBuddyInfo[agent_id]->getRightsGrantedTo()
                    << ", FROM: " << mBuddyInfo[agent_id]->getRightsGrantedFrom()
                    << LL_ENDL;
        }
        else
        {
            LLRelationship* e_r = (*existing_buddy).second;
            LLRelationship* n_r = (*itr).second;
            LL_WARNS() << "!! Add buddy for existing buddy: " << agent_id
                    << " [" << (e_r->isOnline() ? "Online" : "Offline") << "->" << (n_r->isOnline() ? "Online" : "Offline")
                    << ", " <<  e_r->getRightsGrantedTo() << "->" << n_r->getRightsGrantedTo()
                    << ", " <<  e_r->getRightsGrantedTo() << "->" << n_r->getRightsGrantedTo()
                    << "]" << LL_ENDL;
        }
    }
    // do not notify observers here - list can be large so let it be done on idle.

    return new_buddy_count;
}


void LLAvatarTracker::copyBuddyList(buddy_map_t& buddies) const
{
    buddy_map_t::const_iterator it = mBuddyInfo.begin();
    buddy_map_t::const_iterator end = mBuddyInfo.end();
    for(; it != end; ++it)
    {
        buddies[(*it).first] = (*it).second;
    }
}

void LLAvatarTracker::terminateBuddy(const LLUUID& id)
{
    LL_DEBUGS() << "LLAvatarTracker::terminateBuddy()" << LL_ENDL;
    LLUIUsage::instance().logCommand("Agent.TerminateFriendship");

    LLRelationship* buddy = get_ptr_in_map(mBuddyInfo, id);
    if(!buddy) return;
    mBuddyInfo.erase(id);
    LLMessageSystem* msg = gMessageSystem;
    msg->newMessage("TerminateFriendship");
    msg->nextBlock("AgentData");
    msg->addUUID("AgentID", gAgent.getID());
    msg->addUUID("SessionID", gAgent.getSessionID());
    msg->nextBlock("ExBlock");
    msg->addUUID("OtherID", id);
    gAgent.sendReliableMessage();

    addChangedMask(LLFriendObserver::REMOVE, id);
    delete buddy;
}

// get all buddy info
const LLRelationship* LLAvatarTracker::getBuddyInfo(const LLUUID& id) const
{
    if(id.isNull()) return NULL;
    return get_ptr_in_map(mBuddyInfo, id);
}

bool LLAvatarTracker::isBuddy(const LLUUID& id) const
{
    LLRelationship* info = get_ptr_in_map(mBuddyInfo, id);
    return (info != NULL);
}

// online status
void LLAvatarTracker::setBuddyOnline(const LLUUID& id, bool is_online)
{
    LLRelationship* info = get_ptr_in_map(mBuddyInfo, id);
    if(info)
    {
        info->online(is_online);
        addChangedMask(LLFriendObserver::ONLINE, id);
        LL_DEBUGS() << "Set buddy " << id << (is_online ? " Online" : " Offline") << LL_ENDL;
    }
    else
    {
        LL_WARNS() << "!! No buddy info found for " << id
                << ", setting to " << (is_online ? "Online" : "Offline") << LL_ENDL;
    }
}

bool LLAvatarTracker::isBuddyOnline(const LLUUID& id) const
{
    LLRelationship* info = get_ptr_in_map(mBuddyInfo, id);
    if(info)
    {
        return info->isOnline();
    }
    return false;
}

// empowered status
void LLAvatarTracker::setBuddyEmpowered(const LLUUID& id, bool is_empowered)
{
    LLRelationship* info = get_ptr_in_map(mBuddyInfo, id);
    if(info)
    {
        info->grantRights(LLRelationship::GRANT_MODIFY_OBJECTS, 0);
        mModifyMask |= LLFriendObserver::POWERS;
    }
}

bool LLAvatarTracker::isBuddyEmpowered(const LLUUID& id) const
{
    LLRelationship* info = get_ptr_in_map(mBuddyInfo, id);
    if(info)
    {
        return info->isRightGrantedTo(LLRelationship::GRANT_MODIFY_OBJECTS);
    }
    return false;
}

void LLAvatarTracker::empower(const LLUUID& id, bool grant)
{
    // wrapper for ease of use in some situations.
    buddy_map_t list;
    /*
    list.insert(id);
    empowerList(list, grant);
    */
}

void LLAvatarTracker::empowerList(const buddy_map_t& list, bool grant)
{
    LL_WARNS() << "LLAvatarTracker::empowerList() not implemented." << LL_ENDL;
/*
    LLMessageSystem* msg = gMessageSystem;
    const char* message_name;
    const char* block_name;
    const char* field_name;
    if(grant)
    {
        message_name = _PREHASH_GrantModification;
        block_name = _PREHASH_EmpoweredBlock;
        field_name = _PREHASH_EmpoweredID;
    }
    else
    {
        message_name = _PREHASH_RevokeModification;
        block_name = _PREHASH_RevokedBlock;
        field_name = _PREHASH_RevokedID;
    }

    std::string name;
    gAgent.buildFullnameAndTitle(name);

    bool start_new_message = true;
    buddy_list_t::const_iterator it = list.begin();
    buddy_list_t::const_iterator end = list.end();
    for(; it != end; ++it)
    {
        if(NULL == get_ptr_in_map(mBuddyInfo, (*it))) continue;
        setBuddyEmpowered((*it), grant);
        if(start_new_message)
        {
            start_new_message = false;
            msg->newMessageFast(message_name);
            msg->nextBlockFast(_PREHASH_AgentData);
            msg->addUUIDFast(_PREHASH_AgentID, gAgent.getID());
            msg->addUUIDFast(_PREHASH_SessionID, gAgent.getSessionID());
            msg->addStringFast(_PREHASH_GranterName, name);
        }
        msg->nextBlockFast(block_name);
        msg->addUUIDFast(field_name, (*it));
        if(msg->isSendFullFast(block_name))
        {
            start_new_message = true;
            gAgent.sendReliableMessage();
        }
    }
    if(!start_new_message)
    {
        gAgent.sendReliableMessage();
    }
*/
}

void LLAvatarTracker::deleteTrackingData()
{
    //make sure mTrackingData never points to freed memory
    LLTrackingData* tmp = mTrackingData;
    mTrackingData = NULL;
    delete tmp;
}

void LLAvatarTracker::findAgent()
{
    if (!mTrackingData) return;
    if (mTrackingData->mAvatarID.isNull()) return;
    LLMessageSystem* msg = gMessageSystem;
    msg->newMessageFast(_PREHASH_FindAgent); // Request
    msg->nextBlockFast(_PREHASH_AgentBlock);
    msg->addUUIDFast(_PREHASH_Hunter, gAgentID);
    msg->addUUIDFast(_PREHASH_Prey, mTrackingData->mAvatarID);
    msg->addIPAddrFast(_PREHASH_SpaceIP, 0); // will get filled in by simulator
    msg->nextBlockFast(_PREHASH_LocationBlock);
    const F64 NO_LOCATION = 0.0;
    msg->addF64Fast(_PREHASH_GlobalX, NO_LOCATION);
    msg->addF64Fast(_PREHASH_GlobalY, NO_LOCATION);
    gAgent.sendReliableMessage();
}

void LLAvatarTracker::addObserver(LLFriendObserver* observer)
{
    if(observer)
    {
        mObservers.push_back(observer);
    }
}

void LLAvatarTracker::removeObserver(LLFriendObserver* observer)
{
    mObservers.erase(
        std::remove(mObservers.begin(), mObservers.end(), observer),
        mObservers.end());
}

void LLAvatarTracker::idleNotifyObservers()
{
    if (mModifyMask == LLFriendObserver::NONE && mChangedBuddyIDs.size() == 0)
    {
        return;
    }
    notifyObservers();
}

void LLAvatarTracker::notifyObservers()
{
    if (mIsNotifyObservers)
    {
        // Don't allow multiple calls.
        // new masks and ids will be processed later from idle.
        return;
    }
    LL_PROFILE_ZONE_SCOPED;
    mIsNotifyObservers = true;

    observer_list_t observers(mObservers);
    observer_list_t::iterator it = observers.begin();
    observer_list_t::iterator end = observers.end();
    for(; it != end; ++it)
    {
        (*it)->changed(mModifyMask);
    }

    for (changed_buddy_t::iterator it = mChangedBuddyIDs.begin(); it != mChangedBuddyIDs.end(); it++)
    {
        notifyParticularFriendObservers(*it);
    }

    mModifyMask = LLFriendObserver::NONE;
    mChangedBuddyIDs.clear();
    mIsNotifyObservers = false;
}

void LLAvatarTracker::addParticularFriendObserver(const LLUUID& buddy_id, LLFriendObserver* observer)
{
    if (buddy_id.notNull() && observer)
        mParticularFriendObserverMap[buddy_id].insert(observer);
}

void LLAvatarTracker::removeParticularFriendObserver(const LLUUID& buddy_id, LLFriendObserver* observer)
{
    if (buddy_id.isNull() || !observer)
        return;

    observer_map_t::iterator obs_it = mParticularFriendObserverMap.find(buddy_id);
    if(obs_it == mParticularFriendObserverMap.end())
        return;

    obs_it->second.erase(observer);

    // purge empty sets from the map
    if (obs_it->second.size() == 0)
        mParticularFriendObserverMap.erase(obs_it);
}

void LLAvatarTracker::notifyParticularFriendObservers(const LLUUID& buddy_id)
{
    observer_map_t::iterator obs_it = mParticularFriendObserverMap.find(buddy_id);
    if(obs_it == mParticularFriendObserverMap.end())
        return;

    // Notify observers interested in buddy_id.
    observer_set_t& obs = obs_it->second;
    for (observer_set_t::iterator ob_it = obs.begin(); ob_it != obs.end(); ob_it++)
    {
        (*ob_it)->changed(mModifyMask);
    }
}

// store flag for change
// and id of object change applies to
void LLAvatarTracker::addChangedMask(U32 mask, const LLUUID& referent)
{
    mModifyMask |= mask;
    if (referent.notNull())
    {
        mChangedBuddyIDs.insert(referent);
    }
}

void LLAvatarTracker::applyFunctor(LLRelationshipFunctor& f)
{
    buddy_map_t::iterator it = mBuddyInfo.begin();
    buddy_map_t::iterator end = mBuddyInfo.end();
    for(; it != end; ++it)
    {
        f((*it).first, (*it).second);
    }
}

void LLAvatarTracker::registerCallbacks(LLMessageSystem* msg)
{
    msg->setHandlerFuncFast(_PREHASH_FindAgent, processAgentFound);
    msg->setHandlerFuncFast(_PREHASH_OnlineNotification,
                        processOnlineNotification);
    msg->setHandlerFuncFast(_PREHASH_OfflineNotification,
                        processOfflineNotification);
    //msg->setHandlerFuncFast(_PREHASH_GrantedProxies,
    //                  processGrantedProxies);
    msg->setHandlerFunc("TerminateFriendship", processTerminateFriendship);
    msg->setHandlerFunc(_PREHASH_ChangeUserRights, processChangeUserRights);
}

// static
void LLAvatarTracker::processAgentFound(LLMessageSystem* msg, void**)
{
    LLUUID id;


    msg->getUUIDFast(_PREHASH_AgentBlock, _PREHASH_Hunter, id);
    msg->getUUIDFast(_PREHASH_AgentBlock, _PREHASH_Prey, id);
    // *FIX: should make sure prey id matches.
    LLVector3d estimated_global_pos;
    msg->getF64Fast(_PREHASH_LocationBlock, _PREHASH_GlobalX,
                 estimated_global_pos.mdV[VX]);
    msg->getF64Fast(_PREHASH_LocationBlock, _PREHASH_GlobalY,
                 estimated_global_pos.mdV[VY]);
    LLAvatarTracker::instance().agentFound(id, estimated_global_pos);
}

void LLAvatarTracker::agentFound(const LLUUID& prey,
                                 const LLVector3d& estimated_global_pos)
{
    if(!mTrackingData) return;
    //if we get a valid reply from the server, that means the agent
    //is our friend and mappable, so enable interest list based updates
    LLAvatarTracker::instance().setTrackedAgentValid(true);
    mTrackingData->agentFound(prey, estimated_global_pos);
}

//  static
void LLAvatarTracker::processOnlineNotification(LLMessageSystem* msg, void**)
{
    LL_DEBUGS() << "LLAvatarTracker::processOnlineNotification()" << LL_ENDL;
    instance().processNotify(msg, true);
}

//  static
void LLAvatarTracker::processOfflineNotification(LLMessageSystem* msg, void**)
{
    LL_DEBUGS() << "LLAvatarTracker::processOfflineNotification()" << LL_ENDL;
    instance().processNotify(msg, false);
}

void LLAvatarTracker::processChange(LLMessageSystem* msg)
{
    S32 count = msg->getNumberOfBlocksFast(_PREHASH_Rights);
    LLUUID agent_id, agent_related;
    S32 new_rights;
    msg->getUUIDFast(_PREHASH_AgentData, _PREHASH_AgentID, agent_id);
    for(int i = 0; i < count; ++i)
    {
        msg->getUUIDFast(_PREHASH_Rights, _PREHASH_AgentRelated, agent_related, i);
        msg->getS32Fast(_PREHASH_Rights,_PREHASH_RelatedRights, new_rights, i);
        if(agent_id == gAgent.getID())
        {
            if(mBuddyInfo.find(agent_related) != mBuddyInfo.end())
            {
                (mBuddyInfo[agent_related])->setRightsTo(new_rights);
                mChangedBuddyIDs.insert(agent_related);
            }
        }
        else
        {
            if(mBuddyInfo.find(agent_id) != mBuddyInfo.end())
            {
                if (((mBuddyInfo[agent_id]->getRightsGrantedFrom() ^  new_rights) & LLRelationship::GRANT_MODIFY_OBJECTS))
                {
                    LLSD args;
                    args["NAME"] = LLSLURL("agent", agent_id, "displayname").getSLURLString();

                    LLSD payload;
                    payload["from_id"] = agent_id;
                    if(LLRelationship::GRANT_MODIFY_OBJECTS & new_rights)
                    {
                        LLNotifications::instance().add("GrantedModifyRights",args, payload);
                    }
                    else
                    {
                        LLNotifications::instance().add("RevokedModifyRights",args, payload);
                    }
                }
                (mBuddyInfo[agent_id])->setRightsFrom(new_rights);
            }
        }
    }

    addChangedMask(LLFriendObserver::POWERS, agent_id);
    notifyObservers();
}

void LLAvatarTracker::processChangeUserRights(LLMessageSystem* msg, void**)
{
    LL_DEBUGS() << "LLAvatarTracker::processChangeUserRights()" << LL_ENDL;
    instance().processChange(msg);
}

void LLAvatarTracker::processNotify(LLMessageSystem* msg, bool online)
{
    LL_PROFILE_ZONE_SCOPED;
    S32 count = msg->getNumberOfBlocksFast(_PREHASH_AgentBlock);
    bool chat_notify = gSavedSettings.getBOOL("ChatOnlineNotification");

    LL_DEBUGS() << "Received " << count << " online notifications **** " << LL_ENDL;
    if(count > 0)
    {
        LLUUID agent_id;
        const LLRelationship* info = NULL;
        LLUUID tracking_id;
        if(mTrackingData)
        {
            tracking_id = mTrackingData->mAvatarID;
        }
        LLSD payload;
        for(S32 i = 0; i < count; ++i)
        {
            msg->getUUIDFast(_PREHASH_AgentBlock, _PREHASH_AgentID, agent_id, i);
            payload["FROM_ID"] = agent_id;
            info = getBuddyInfo(agent_id);
            if(info)
            {
                setBuddyOnline(agent_id,online);
            }
            else
            {
                LL_WARNS() << "Received online notification for unknown buddy: "
                    << agent_id << " is " << (online ? "ONLINE" : "OFFLINE") << LL_ENDL;
            }

            if(tracking_id == agent_id)
            {
                // we were tracking someone who went offline
                deleteTrackingData();
            }

            if(chat_notify)
            {
                // Look up the name of this agent for the notification
                LLAvatarNameCache::get(agent_id,boost::bind(&on_avatar_name_cache_notify,_1, _2, online, payload));
            }
        }

        mModifyMask |= LLFriendObserver::ONLINE;
        instance().notifyObservers();
        gInventory.notifyObservers();
    }
}

static void on_avatar_name_cache_notify(const LLUUID& agent_id,
                                        const LLAvatarName& av_name,
                                        bool online,
                                        LLSD payload)
{
    // Popup a notify box with online status of this agent
    // Use display name only because this user is your friend
    LLSD args;
    args["NAME"] = av_name.getDisplayName();
    args["STATUS"] = online ? LLTrans::getString("OnlineStatus") : LLTrans::getString("OfflineStatus");

    LLNotificationPtr notification;
    if (online)
    {
        notification =
            LLNotifications::instance().add("FriendOnlineOffline",
                                     args,
                                     payload.with("respond_on_mousedown", true),
                                     boost::bind(&LLAvatarActions::startIM, agent_id));
    }
    else
    {
        notification =
            LLNotifications::instance().add("FriendOnlineOffline", args, payload);
    }

    // If there's an open IM session with this agent, send a notification there too.
    LLUUID session_id = LLIMMgr::computeSessionID(IM_NOTHING_SPECIAL, agent_id);
    std::string notify_msg = notification->getMessage();
    LLIMModel::instance().proccessOnlineOfflineNotification(session_id, notify_msg);
}

void LLAvatarTracker::formFriendship(const LLUUID& id)
{
    if(id.notNull())
    {
        LLRelationship* buddy_info = get_ptr_in_map(instance().mBuddyInfo, id);
        if(!buddy_info)
        {
            LLAvatarTracker& at = LLAvatarTracker::instance();
            //The default for relationship establishment is to have both parties
            //visible online to each other.
            buddy_info = new LLRelationship(LLRelationship::GRANT_ONLINE_STATUS,LLRelationship::GRANT_ONLINE_STATUS, false);
            at.mBuddyInfo[id] = buddy_info;
            at.addChangedMask(LLFriendObserver::ADD, id);
            at.notifyObservers();
        }
    }
}

void LLAvatarTracker::processTerminateFriendship(LLMessageSystem* msg, void**)
{
    LLUUID id;
    msg->getUUID("ExBlock", "OtherID", id);
    if(id.notNull())
    {
        LLAvatarTracker& at = LLAvatarTracker::instance();
        LLRelationship* buddy = get_ptr_in_map(at.mBuddyInfo, id);
        if(!buddy) return;
        at.mBuddyInfo.erase(id);
        at.addChangedMask(LLFriendObserver::REMOVE, id);
        delete buddy;
        at.notifyObservers();
    }
}

///----------------------------------------------------------------------------
/// Tracking Data
///----------------------------------------------------------------------------

LLTrackingData::LLTrackingData(const LLUUID& avatar_id, const std::string& name)
:   mAvatarID(avatar_id),
    mHaveInfo(false),
    mHaveCoarseInfo(false)
{
    mCoarseLocationTimer.setTimerExpirySec(COARSE_FREQUENCY);
    mUpdateTimer.setTimerExpirySec(FIND_FREQUENCY);
    mAgentGone.setTimerExpirySec(OFFLINE_SECONDS);
    if(!name.empty())
    {
        mName = name;
    }
}

void LLTrackingData::agentFound(const LLUUID& prey,
                                const LLVector3d& estimated_global_pos)
{
    if(prey != mAvatarID)
    {
        LL_WARNS() << "LLTrackingData::agentFound() - found " << prey
                << " but looking for " << mAvatarID << LL_ENDL;
    }
    mHaveInfo = true;
    mAgentGone.setTimerExpirySec(OFFLINE_SECONDS);
    mGlobalPositionEstimate = estimated_global_pos;
}

bool LLTrackingData::haveTrackingInfo()
{
    LLViewerObject* object = gObjectList.findObject(mAvatarID);
    if(object && !object->isDead())
    {
        mCoarseLocationTimer.checkExpirationAndReset(COARSE_FREQUENCY);
        mUpdateTimer.setTimerExpirySec(FIND_FREQUENCY);
        mAgentGone.setTimerExpirySec(OFFLINE_SECONDS);
        mHaveInfo = true;
        return true;
    }
    if(mHaveCoarseInfo &&
       !mCoarseLocationTimer.checkExpirationAndReset(COARSE_FREQUENCY))
    {
        // if we reach here, then we have a 'recent' coarse update
        mUpdateTimer.setTimerExpirySec(FIND_FREQUENCY);
        mAgentGone.setTimerExpirySec(OFFLINE_SECONDS);
        return true;
    }
    if(mUpdateTimer.checkExpirationAndReset(FIND_FREQUENCY))
    {
        LLAvatarTracker::instance().findAgent();
        mHaveCoarseInfo = false;
    }
    if(mAgentGone.checkExpirationAndReset(OFFLINE_SECONDS))
    {
        mHaveInfo = false;
        mHaveCoarseInfo = false;
    }
    return mHaveInfo;
}

void LLTrackingData::setTrackedCoarseLocation(const LLVector3d& global_pos)
{
    mCoarseLocationTimer.setTimerExpirySec(COARSE_FREQUENCY);
    mGlobalPositionEstimate = global_pos;
    mHaveInfo = true;
    mHaveCoarseInfo = true;
}

///----------------------------------------------------------------------------
// various buddy functors
///----------------------------------------------------------------------------

bool LLCollectProxyBuddies::operator()(const LLUUID& buddy_id, LLRelationship* buddy)
{
    if(buddy->isRightGrantedFrom(LLRelationship::GRANT_MODIFY_OBJECTS))
    {
        mProxy.insert(buddy_id);
    }
    return true;
}

bool LLCollectMappableBuddies::operator()(const LLUUID& buddy_id, LLRelationship* buddy)
{
    LLAvatarName av_name;
    LLAvatarNameCache::get( buddy_id, &av_name);
    buddy_map_t::value_type value(buddy_id, av_name.getDisplayName());
    if(buddy->isOnline() && buddy->isRightGrantedFrom(LLRelationship::GRANT_MAP_LOCATION))
    {
        mMappable.insert(value);
    }
    return true;
}

bool LLCollectOnlineBuddies::operator()(const LLUUID& buddy_id, LLRelationship* buddy)
{
    LLAvatarName av_name;
    LLAvatarNameCache::get(buddy_id, &av_name);
    mFullName = av_name.getUserName();
    buddy_map_t::value_type value(buddy_id, mFullName);
    if(buddy->isOnline())
    {
        mOnline.insert(value);
    }
    return true;
}

bool LLCollectAllBuddies::operator()(const LLUUID& buddy_id, LLRelationship* buddy)
{
    LLAvatarName av_name;
    LLAvatarNameCache::get(buddy_id, &av_name);
    mFullName = av_name.getCompleteName();
    buddy_map_t::value_type value(buddy_id, mFullName);
    if(buddy->isOnline())
    {
        mOnline.insert(value);
    }
    else
    {
        mOffline.insert(value);
    }
    return true;
}