/**
* @file llnotifications.cpp
* @brief Non-UI queue manager for keeping a prioritized list of notifications
*
* $LicenseInfo:firstyear=2008&license=viewergpl$
* 
* Copyright (c) 2008-2009, Linden Research, Inc.
* 
* Second Life Viewer Source Code
* The source code in this file ("Source Code") is provided by Linden Lab
* to you under the terms of the GNU General Public License, version 2.0
* ("GPL"), unless you have obtained a separate licensing agreement
* ("Other License"), formally executed by you and Linden Lab.  Terms of
* the GPL can be found in doc/GPL-license.txt in this distribution, or
* online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
* 
* There are special exceptions to the terms and conditions of the GPL as
* it is applied to this Source Code. View the full text of the exception
* in the file doc/FLOSS-exception.txt in this software distribution, or
* online at
* http://secondlifegrid.net/programs/open_source/licensing/flossexception
* 
* By copying, modifying or distributing this software, you acknowledge
* that you have read and understood your obligations described above,
* and agree to abide by those obligations.
* 
* ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
* WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
* COMPLETENESS OR PERFORMANCE.
* $/LicenseInfo$
*/

#include "linden_common.h"
#include "lluictrlfactory.h"
#include "lldir.h"
#include "llsdserialize.h"

#include "llnotifications.h"

#include <algorithm>
#include <boost/regex.hpp>


const std::string NOTIFICATION_PERSIST_VERSION = "0.93";

// local channel for notification history
class LLNotificationHistoryChannel : public LLNotificationChannel
{
	LOG_CLASS(LLNotificationHistoryChannel);
public:
	LLNotificationHistoryChannel(const std::string& filename) : 
		LLNotificationChannel("History", "Visible", &historyFilter, LLNotificationComparators::orderByUUID()),
		mFileName(filename)
	{
		connectChanged(boost::bind(&LLNotificationHistoryChannel::historyHandler, this, _1));
		loadPersistentNotifications();
	}

private:
	bool historyHandler(const LLSD& payload)
	{
		// we ignore "load" messages, but rewrite the persistence file on any other
		std::string sigtype = payload["sigtype"];
		if (sigtype != "load")
		{
			savePersistentNotifications();
		}
		return false;
	}

	// The history channel gets all notifications except those that have been cancelled
	static bool historyFilter(LLNotificationPtr pNotification)
	{
		return !pNotification->isCancelled();
	}

	void savePersistentNotifications()
	{
		llinfos << "Saving open notifications to " << mFileName << llendl;

		llofstream notify_file(mFileName.c_str());
		if (!notify_file.is_open()) 
		{
			llwarns << "Failed to open " << mFileName << llendl;
			return;
		}

		LLSD output;
		output["version"] = NOTIFICATION_PERSIST_VERSION;
		LLSD& data = output["data"];

		for (LLNotificationSet::iterator it = mItems.begin(); it != mItems.end(); ++it)
		{
			if (!LLNotifications::instance().templateExists((*it)->getName())) continue;

			// only store notifications flagged as persisting
			LLNotificationTemplatePtr templatep = LLNotifications::instance().getTemplate((*it)->getName());
			if (!templatep->mPersist) continue;

			data.append((*it)->asLLSD());
		}

		LLPointer<LLSDFormatter> formatter = new LLSDXMLFormatter();
		formatter->format(output, notify_file, LLSDFormatter::OPTIONS_PRETTY);
	}

	void loadPersistentNotifications()
	{
		llinfos << "Loading open notifications from " << mFileName << llendl;

		llifstream notify_file(mFileName.c_str());
		if (!notify_file.is_open()) 
		{
			llwarns << "Failed to open " << mFileName << llendl;
			return;
		}

		LLSD input;
		LLPointer<LLSDParser> parser = new LLSDXMLParser();
		if (parser->parse(notify_file, input, LLSDSerialize::SIZE_UNLIMITED) < 0)
		{
			llwarns << "Failed to parse open notifications" << llendl;
			return;
		}

		if (input.isUndefined()) return;
		std::string version = input["version"];
		if (version != NOTIFICATION_PERSIST_VERSION)
		{
			llwarns << "Bad open notifications version: " << version << llendl;
			return;
		}
		LLSD& data = input["data"];
		if (data.isUndefined()) return;

		LLNotifications& instance = LLNotifications::instance();
		for (LLSD::array_const_iterator notification_it = data.beginArray();
			notification_it != data.endArray();
			++notification_it)
		{
			instance.add(LLNotificationPtr(new LLNotification(*notification_it)));
		}
	}

	//virtual
	void onDelete(LLNotificationPtr pNotification)
	{
		// we want to keep deleted notifications in our log
		mItems.insert(pNotification);
		
		return;
	}
	
private:
	std::string mFileName;
};

bool filterIgnoredNotifications(LLNotificationPtr notification)
{
	LLNotificationFormPtr form = notification->getForm();
	// Check to see if the user wants to ignore this alert
	if (form->getIgnoreType() != LLNotificationForm::IGNORE_NO)
	{
		return LLUI::sConfigGroup->getWarning(notification->getName());
	}

	return true;
}

bool handleIgnoredNotification(const LLSD& payload)
{
	if (payload["sigtype"].asString() == "add")
	{
		LLNotificationPtr pNotif = LLNotifications::instance().find(payload["id"].asUUID());
		if (!pNotif) return false;

		LLNotificationFormPtr form = pNotif->getForm();
		LLSD response;
		switch(form->getIgnoreType())
		{
		case LLNotificationForm::IGNORE_WITH_DEFAULT_RESPONSE:
			response = pNotif->getResponseTemplate(LLNotification::WITH_DEFAULT_BUTTON);
			break;
		case LLNotificationForm::IGNORE_WITH_LAST_RESPONSE:
			response = LLUI::sIgnoresGroup->getLLSD("Default" + pNotif->getName());
			break;
		case LLNotificationForm::IGNORE_SHOW_AGAIN:
			break;
		default:
			return false;
		}
		pNotif->setIgnored(true);
		pNotif->respond(response);
		return true; 	// don't process this item any further
	}
	return false;
}

namespace LLNotificationFilters
{
	// a sample filter
	bool includeEverything(LLNotificationPtr p)
	{
		return true;
	}
};

LLNotificationForm::LLNotificationForm()
:	mFormData(LLSD::emptyArray()),
	mIgnore(IGNORE_NO)
{
}


LLNotificationForm::LLNotificationForm(const std::string& name, const LLXMLNodePtr xml_node) 
:	mFormData(LLSD::emptyArray()),
	mIgnore(IGNORE_NO)
{
	if (!xml_node->hasName("form"))
	{
		llwarns << "Bad xml node for form: " << xml_node->getName() << llendl;
	}
	LLXMLNodePtr child = xml_node->getFirstChild();
	while(child)
	{
		child = LLNotifications::instance().checkForXMLTemplate(child);

		LLSD item_entry;
		std::string element_name = child->getName()->mString;

		if (element_name == "ignore")
		{
			bool save_option = false;
			child->getAttribute_bool("save_option", save_option);
			if (!save_option)
			{
				mIgnore = IGNORE_WITH_DEFAULT_RESPONSE;
			}
			else
			{
				// remember last option chosen by user and automatically respond with that in the future
				mIgnore = IGNORE_WITH_LAST_RESPONSE;
				LLUI::sIgnoresGroup->declareLLSD(std::string("Default") + name, "", std::string("Default response for notification " + name));
			}
			child->getAttributeString("text", mIgnoreMsg);
			LLUI::sIgnoresGroup->addWarning(name);
		}
		else
		{
			// flatten xml form entry into single LLSD map with type==name
			item_entry["type"] = element_name;
			const LLXMLAttribList::iterator attrib_end = child->mAttributes.end();
			for(LLXMLAttribList::iterator attrib_it = child->mAttributes.begin();
				attrib_it != attrib_end;
				++attrib_it)
			{
				item_entry[std::string(attrib_it->second->getName()->mString)] = attrib_it->second->getValue();
			}
			item_entry["value"] = child->getTextContents();
			mFormData.append(item_entry);
		}

		child = child->getNextSibling();
	}
}

LLNotificationForm::LLNotificationForm(const LLSD& sd)
{
	if (sd.isArray())
	{
		mFormData = sd;
	}
	else
	{
		llwarns << "Invalid form data " << sd << llendl;
		mFormData = LLSD::emptyArray();
	}
}

LLSD LLNotificationForm::asLLSD() const
{ 
	return mFormData; 
}

LLSD LLNotificationForm::getElement(const std::string& element_name)
{
	for (LLSD::array_const_iterator it = mFormData.beginArray();
		it != mFormData.endArray();
		++it)
	{
		if ((*it)["name"].asString() == element_name) return (*it);
	}
	return LLSD();
}


bool LLNotificationForm::hasElement(const std::string& element_name)
{
	for (LLSD::array_const_iterator it = mFormData.beginArray();
		it != mFormData.endArray();
		++it)
	{
		if ((*it)["name"].asString() == element_name) return true;
	}
	return false;
}

void LLNotificationForm::addElement(const std::string& type, const std::string& name, const LLSD& value)
{
	LLSD element;
	element["type"] = type;
	element["name"] = name;
	element["label"] = name;
	element["value"] = value;
	element["index"] = mFormData.size();
	mFormData.append(element);
}

void LLNotificationForm::append(const LLSD& sub_form)
{
	if (sub_form.isArray())
	{
		for (LLSD::array_const_iterator it = sub_form.beginArray();
			it != sub_form.endArray();
			++it)
		{
			mFormData.append(*it);
		}
	}
}

void LLNotificationForm::formatElements(const LLSD& substitutions)
{
	for (LLSD::array_iterator it = mFormData.beginArray();
		it != mFormData.endArray();
		++it)
	{
		// format "text" component of each form element
		if ((*it).has("text"))
		{
			std::string text = (*it)["text"].asString();
			text = LLNotification::format(text, substitutions);
			(*it)["text"] = text;
		}
		if ((*it)["type"].asString() == "text" && (*it).has("value"))
		{
			std::string value = (*it)["value"].asString();
			value = LLNotification::format(value, substitutions);
			(*it)["value"] = value;
		}
	}
}

std::string LLNotificationForm::getDefaultOption()
{
	for (LLSD::array_const_iterator it = mFormData.beginArray();
		it != mFormData.endArray();
		++it)
	{
		if ((*it)["default"]) return (*it)["name"].asString();
	}
	return "";
}

LLNotificationTemplate::LLNotificationTemplate() :
	mExpireSeconds(0),
	mExpireOption(-1),
	mURLOption(-1),
	mUnique(false),
	mPriority(NOTIFICATION_PRIORITY_NORMAL)
{
	mForm = LLNotificationFormPtr(new LLNotificationForm()); 
}

LLNotification::LLNotification(const LLNotification::Params& p) : 
	mTimestamp(p.timestamp), 
	mSubstitutions(p.substitutions),
	mPayload(p.payload),
	mExpiresAt(0),
	mResponseFunctorName(p.functor_name),
	mTemporaryResponder(p.mTemporaryResponder),
	mRespondedTo(false),
	mPriority(p.priority),
	mCancelled(false),
	mIgnored(false)
{
	mId.generate();
	init(p.name, p.form_elements);
}


LLNotification::LLNotification(const LLSD& sd) :
	mTemporaryResponder(false),
	mRespondedTo(false),
	mCancelled(false),
	mIgnored(false)
{ 
	mId.generate();
	mSubstitutions = sd["substitutions"];
	mPayload = sd["payload"]; 
	mTimestamp = sd["time"]; 
	mExpiresAt = sd["expiry"];
	mPriority = (ENotificationPriority)sd["priority"].asInteger();
	mResponseFunctorName = sd["responseFunctor"].asString();
	std::string templatename = sd["name"].asString();
	init(templatename, LLSD());
	// replace form with serialized version
	mForm = LLNotificationFormPtr(new LLNotificationForm(sd["form"]));
}


LLSD LLNotification::asLLSD()
{
	LLSD output;
	output["name"] = mTemplatep->mName;
	output["form"] = getForm()->asLLSD();
	output["substitutions"] = mSubstitutions;
	output["payload"] = mPayload;
	output["time"] = mTimestamp;
	output["expiry"] = mExpiresAt;
	output["priority"] = (S32)mPriority;
	output["responseFunctor"] = mResponseFunctorName;
	return output;
}

void LLNotification::update()
{
	LLNotifications::instance().update(shared_from_this());
}

void LLNotification::updateFrom(LLNotificationPtr other)
{
	// can only update from the same notification type
	if (mTemplatep != other->mTemplatep) return;

	// NOTE: do NOT change the ID, since it is the key to
	// this given instance, just update all the metadata
	//mId = other->mId;

	mPayload = other->mPayload;
	mSubstitutions = other->mSubstitutions;
	mTimestamp = other->mTimestamp;
	mExpiresAt = other->mExpiresAt;
	mCancelled = other->mCancelled;
	mIgnored = other->mIgnored;
	mPriority = other->mPriority;
	mForm = other->mForm;
	mResponseFunctorName = other->mResponseFunctorName;
	mRespondedTo = other->mRespondedTo;
	mTemporaryResponder = other->mTemporaryResponder;

	update();
}

const LLNotificationFormPtr LLNotification::getForm()
{
	return mForm;
}

void LLNotification::cancel()
{
	mCancelled = true;
}

LLSD LLNotification::getResponseTemplate(EResponseTemplateType type)
{
	LLSD response = LLSD::emptyMap();
	for (S32 element_idx = 0;
		element_idx < mForm->getNumElements();
		++element_idx)
	{
		LLSD element = mForm->getElement(element_idx);
		if (element.has("name"))
		{
			response[element["name"].asString()] = element["value"];
		}

		if ((type == WITH_DEFAULT_BUTTON) 
			&& element["default"].asBoolean())
		{
			response[element["name"].asString()] = true;
		}
	}
	return response;
}

//static
S32 LLNotification::getSelectedOption(const LLSD& notification, const LLSD& response)
{
	LLNotificationForm form(notification["form"]);

	for (S32 element_idx = 0;
		element_idx < form.getNumElements();
		++element_idx)
	{
		LLSD element = form.getElement(element_idx);

		// only look at buttons
		if (element["type"].asString() == "button" 
			&& response[element["name"].asString()].asBoolean())
		{
			return element["index"].asInteger();
		}
	}

	return -1;
}

//static
std::string LLNotification::getSelectedOptionName(const LLSD& response)
{
	for (LLSD::map_const_iterator response_it = response.beginMap();
		response_it != response.endMap();
		++response_it)
	{
		if (response_it->second.isBoolean() && response_it->second.asBoolean())
		{
			return response_it->first;
		}
	}
	return "";
}


void LLNotification::respond(const LLSD& response)
{
	mRespondedTo = true;
	LLNotificationFunctorRegistry::instance().getFunctor(mResponseFunctorName)(asLLSD(), response);
	if (mTemporaryResponder)
	{
		LLNotificationFunctorRegistry::instance().unregisterFunctor(mResponseFunctorName);
		mResponseFunctorName = "";
		mTemporaryResponder = false;
	}

	if (mForm->getIgnoreType() != LLNotificationForm::IGNORE_NO)
	{
		LLUI::sIgnoresGroup->setWarning(getName(), !mIgnored);
		if (mIgnored && mForm->getIgnoreType() == LLNotificationForm::IGNORE_WITH_LAST_RESPONSE)
		{
			LLUI::sIgnoresGroup->setLLSD("Default" + getName(), response);
		}
	}

	update();
}

void LLNotification::setIgnored(bool ignore)
{
	mIgnored = ignore;
}

void LLNotification::setResponseFunctor(std::string const &responseFunctorName)
{
	if (mTemporaryResponder)
		// get rid of the old one
		LLNotificationFunctorRegistry::instance().unregisterFunctor(mResponseFunctorName);
	mResponseFunctorName = responseFunctorName;
	mTemporaryResponder = false;
}

bool LLNotification::payloadContainsAll(const std::vector<std::string>& required_fields) const
{
	for(std::vector<std::string>::const_iterator required_fields_it = required_fields.begin(); 
		required_fields_it != required_fields.end();
		required_fields_it++)
	{
		std::string required_field_name = *required_fields_it;
		if( ! getPayload().has(required_field_name))
		{
			return false; // a required field was not found
		}
	}
	return true; // all required fields were found
}

bool LLNotification::isEquivalentTo(LLNotificationPtr that) const
{
	if (this->mTemplatep->mName != that->mTemplatep->mName) 
	{
		return false; // must have the same template name or forget it
	}
	if (this->mTemplatep->mUnique)
	{
		// highlander bit sez there can only be one of these
		return
			this->payloadContainsAll(that->mTemplatep->mUniqueContext) &&
			that->payloadContainsAll(this->mTemplatep->mUniqueContext);
	}
	return false; 
}

void LLNotification::init(const std::string& template_name, const LLSD& form_elements)
{
	mTemplatep = LLNotifications::instance().getTemplate(template_name);
	if (!mTemplatep) return;

	// add default substitutions
	// TODO: change this to read from the translatable strings file!
	mSubstitutions["SECOND_LIFE"] = "Second Life";
	mSubstitutions["_URL"] = getURL();
	mSubstitutions["_NAME"] = template_name;
	// TODO: something like this so that a missing alert is sensible:
	//mSubstitutions["_ARGS"] = get_all_arguments_as_text(mSubstitutions);

	mForm = LLNotificationFormPtr(new LLNotificationForm(*mTemplatep->mForm));
	mForm->append(form_elements);

	// apply substitution to form labels
	mForm->formatElements(mSubstitutions);

	LLDate rightnow = LLDate::now();
	if (mTemplatep->mExpireSeconds)
	{
		mExpiresAt = LLDate(rightnow.secondsSinceEpoch() + mTemplatep->mExpireSeconds);
	}

	if (mPriority == NOTIFICATION_PRIORITY_UNSPECIFIED)
	{
		mPriority = mTemplatep->mPriority;
	}
}

std::string LLNotification::summarize() const
{
	std::string s = "Notification(";
	s += getName();
	s += ") : ";
	s += mTemplatep ? mTemplatep->mMessage : "";
	// should also include timestamp and expiration time (but probably not payload)
	return s;
}

//static
std::string LLNotification::format(const std::string& s, const LLSD& substitutions)
{
	if (!substitutions.isMap()) 
	{
		return s;
	}

	std::ostringstream output;
	// match strings like [NAME]
	const boost::regex key("\\[([0-9_A-Z]+)]");
	
	std::string::const_iterator start = s.begin();
	std::string::const_iterator end = s.end();
	boost::smatch match;
	
	while (boost::regex_search(start, end, match, key, boost::match_default))
	{
		bool found_replacement = false;
		std::string replacement;
		
		// see if we have a replacement for the bracketed string (without the brackets)
		// test first using has() because if we just look up with operator[] we get back an
		// empty string even if the value is missing. We want to distinguish between 
		// missing replacements and deliberately empty replacement strings.
		if (substitutions.has(std::string(match[1].first, match[1].second)))
		{
			replacement = substitutions[std::string(match[1].first, match[1].second)].asString();
			found_replacement = true;
		}
		// if not, see if there's one WITH brackets
		else if (substitutions.has(std::string(match[0].first, match[0].second)))
		{
			replacement = substitutions[std::string(match[0].first, match[0].second)].asString();
			found_replacement = true;
		}
		
		if (found_replacement)
		{
			// found a replacement
			// "hello world" is output
			output << std::string(start, match[0].first) << replacement;
		}
		else
		{
			// we had no replacement, so leave the string we searched for so that it gets noticed by QA
			// "hello [NAME_NOT_FOUND]" is output
			output << std::string(start, match[0].second);
		}
		
		// update search position 
		start = match[0].second; 
	}
	// send the remainder of the string (with no further matches for bracketed names)
	output << std::string(start, end);
	return output.str();
}

std::string LLNotification::getMessage() const
{
	// all our callers cache this result, so it gives us more flexibility
	// to do the substitution at call time rather than attempting to 
	// cache it in the notification
	if (!mTemplatep)
		return std::string();
	return format(mTemplatep->mMessage, mSubstitutions);
}

std::string LLNotification::getLabel() const
{
	return (mTemplatep ? format(mTemplatep->mLabel, mSubstitutions) : "");
}



// =========================================================
// LLNotificationChannel implementation
// ---
void LLNotificationChannelBase::connectChanged(const LLStandardSignal::slot_type& slot)
{
	// when someone wants to connect to a channel, we first throw them
	// all of the notifications that are already in the channel
	// we use a special signal called "load" in case the channel wants to care
	// only about new notifications
	for (LLNotificationSet::iterator it = mItems.begin(); it != mItems.end(); ++it)
	{
		slot.get_slot_function()(LLSD().insert("sigtype", "load").insert("id", (*it)->id()));
	}
	// and then connect the signal so that all future notifications will also be
	// forwarded.
	mChanged.connect(slot);
}

void LLNotificationChannelBase::connectPassedFilter(const LLStandardSignal::slot_type& slot)
{
	// these two filters only fire for notifications added after the current one, because
	// they don't participate in the hierarchy.
	mPassedFilter.connect(slot);
}

void LLNotificationChannelBase::connectFailedFilter(const LLStandardSignal::slot_type& slot)
{
	mFailedFilter.connect(slot);
}

// external call, conforms to our standard signature
bool LLNotificationChannelBase::updateItem(const LLSD& payload)
{	
	// first check to see if it's in the master list
	LLNotificationPtr pNotification	 = LLNotifications::instance().find(payload["id"]);
	if (!pNotification)
		return false;	// not found
	
	return updateItem(payload, pNotification);
}


//FIX QUIT NOT WORKING


// internal call, for use in avoiding lookup
bool LLNotificationChannelBase::updateItem(const LLSD& payload, LLNotificationPtr pNotification)
{	
	std::string cmd = payload["sigtype"];
	LLNotificationSet::iterator foundItem = mItems.find(pNotification);
	bool wasFound = (foundItem != mItems.end());
	bool passesFilter = mFilter(pNotification);
	
	// first, we offer the result of the filter test to the simple
	// signals for pass/fail. One of these is guaranteed to be called.
	// If either signal returns true, the change processing is NOT performed
	// (so don't return true unless you know what you're doing!)
	bool abortProcessing = false;
	if (passesFilter)
	{
		abortProcessing = mPassedFilter(payload);
	}
	else
	{
		abortProcessing = mFailedFilter(payload);
	}
	
	if (abortProcessing)
	{
		return true;
	}
	
	if (cmd == "load")
	{
		// should be no reason we'd ever get a load if we already have it
		// if passes filter send a load message, else do nothing
		assert(!wasFound);
		if (passesFilter)
		{
			// not in our list, add it and say so
			mItems.insert(pNotification);
			abortProcessing = mChanged(payload);
			onLoad(pNotification);
		}
	}
	else if (cmd == "change")
	{
		// if it passes filter now and was found, we just send a change message
		// if it passes filter now and wasn't found, we have to add it
		// if it doesn't pass filter and wasn't found, we do nothing
		// if it doesn't pass filter and was found, we need to delete it
		if (passesFilter)
		{
			if (wasFound)
			{
				// it already existed, so this is a change
				// since it changed in place, all we have to do is resend the signal
				abortProcessing = mChanged(payload);
				onChange(pNotification);
			}
			else
			{
				// not in our list, add it and say so
				mItems.insert(pNotification);
				// our payload is const, so make a copy before changing it
				LLSD newpayload = payload;
				newpayload["sigtype"] = "add";
				abortProcessing = mChanged(newpayload);
				onChange(pNotification);
			}
		}
		else
		{
			if (wasFound)
			{
				// it already existed, so this is a delete
				mItems.erase(pNotification);
				// our payload is const, so make a copy before changing it
				LLSD newpayload = payload;
				newpayload["sigtype"] = "delete";
				abortProcessing = mChanged(newpayload);
				onChange(pNotification);
			}
			// didn't pass, not on our list, do nothing
		}
	}
	else if (cmd == "add")
	{
		// should be no reason we'd ever get an add if we already have it
		// if passes filter send an add message, else do nothing
		assert(!wasFound);
		if (passesFilter)
		{
			// not in our list, add it and say so
			mItems.insert(pNotification);
			abortProcessing = mChanged(payload);
			onAdd(pNotification);
		}
	}
	else if (cmd == "delete")
	{
		// if we have it in our list, pass on the delete, then delete it, else do nothing
		if (wasFound)
		{
			abortProcessing = mChanged(payload);
			mItems.erase(pNotification);
			onDelete(pNotification);
		}
	}
	return abortProcessing;
}

/* static */
LLNotificationChannelPtr LLNotificationChannel::buildChannel(const std::string& name, 
															 const std::string& parent,
															 LLNotificationFilter filter, 
															 LLNotificationComparator comparator)
{
	// note: this is not a leak; notifications are self-registering.
	// This factory helps to prevent excess deletions by making sure all smart
	// pointers to notification channels come from the same source
	new LLNotificationChannel(name, parent, filter, comparator);
	return LLNotifications::instance().getChannel(name);
}


LLNotificationChannel::LLNotificationChannel(const std::string& name, 
											 const std::string& parent,
											 LLNotificationFilter filter, 
											 LLNotificationComparator comparator) : 
LLNotificationChannelBase(filter, comparator),
mName(name),
mParent(parent)
{
	// store myself in the channel map
	LLNotifications::instance().addChannel(LLNotificationChannelPtr(this));
	// bind to notification broadcast
	if (parent.empty())
	{
		LLNotifications::instance().connectChanged(
			boost::bind(&LLNotificationChannelBase::updateItem, this, _1));
	}
	else
	{
		LLNotificationChannelPtr p = LLNotifications::instance().getChannel(parent);
		LLStandardSignal::slot_type f = boost::bind(&LLNotificationChannelBase::updateItem, this, _1);
		p->connectChanged(f);
	}
}


void LLNotificationChannel::setComparator(LLNotificationComparator comparator) 
{ 
	mComparator = comparator; 
	LLNotificationSet s2(mComparator);
	s2.insert(mItems.begin(), mItems.end());
	mItems.swap(s2);
	
	// notify clients that we've been resorted
	mChanged(LLSD().insert("sigtype", "sort")); 
}

bool LLNotificationChannel::isEmpty() const
{
	return mItems.empty();
}

LLNotificationChannel::Iterator LLNotificationChannel::begin()
{
	return mItems.begin();
}

LLNotificationChannel::Iterator LLNotificationChannel::end()
{
	return mItems.end();
}

std::string LLNotificationChannel::summarize()
{
	std::string s("Channel '");
	s += mName;
	s += "'\n  ";
	for (LLNotificationChannel::Iterator it = begin(); it != end(); ++it)
	{
		s += (*it)->summarize();
		s += "\n  ";
	}
	return s;
}


// ---
// END OF LLNotificationChannel implementation
// =========================================================


// =========================================================
// LLNotifications implementation
// ---
LLNotifications::LLNotifications() : LLNotificationChannelBase(LLNotificationFilters::includeEverything,
															   LLNotificationComparators::orderByUUID())
{
}


// The expiration channel gets all notifications that are cancelled
bool LLNotifications::expirationFilter(LLNotificationPtr pNotification)
{
	return pNotification->isCancelled() || pNotification->isRespondedTo();
}

bool LLNotifications::expirationHandler(const LLSD& payload)
{
	if (payload["sigtype"].asString() != "delete")
	{
		// anything added to this channel actually should be deleted from the master
		cancel(find(payload["id"]));
		return true;	// don't process this item any further
	}
	return false;
}

bool LLNotifications::uniqueFilter(LLNotificationPtr pNotif)
{
	if (!pNotif->hasUniquenessConstraints())
	{
		return true;
	}

	// checks against existing unique notifications
	for (LLNotificationMap::iterator existing_it = mUniqueNotifications.find(pNotif->getName());
		existing_it != mUniqueNotifications.end();
		++existing_it)
	{
		LLNotificationPtr existing_notification = existing_it->second;
		if (pNotif != existing_notification 
			&& pNotif->isEquivalentTo(existing_notification))
		{
			return false;
		}
	}

	return true;
}

bool LLNotifications::uniqueHandler(const LLSD& payload)
{
	LLNotificationPtr pNotif = LLNotifications::instance().find(payload["id"].asUUID());
	if (pNotif && pNotif->hasUniquenessConstraints()) 
	{
		if (payload["sigtype"].asString() == "add")
		{
			// not a duplicate according to uniqueness criteria, so we keep it
			// and store it for future uniqueness checks
			mUniqueNotifications.insert(std::make_pair(pNotif->getName(), pNotif));
		}
		else if (payload["sigtype"].asString() == "delete")
		{
			mUniqueNotifications.erase(pNotif->getName());
		}
	}

	return false;
}

bool LLNotifications::failedUniquenessTest(const LLSD& payload)
{
	LLNotificationPtr pNotif = LLNotifications::instance().find(payload["id"].asUUID());
	
	if (!pNotif || !pNotif->hasUniquenessConstraints())
	{
		return false;
	}

	// checks against existing unique notifications
	for (LLNotificationMap::iterator existing_it = mUniqueNotifications.find(pNotif->getName());
		existing_it != mUniqueNotifications.end();
		++existing_it)
	{
		LLNotificationPtr existing_notification = existing_it->second;
		if (pNotif != existing_notification 
			&& pNotif->isEquivalentTo(existing_notification))
		{
			// copy notification instance data over to oldest instance
			// of this unique notification and update it
			existing_notification->updateFrom(pNotif);
			// then delete the new one
			pNotif->cancel();
		}
	}

	return false;
}


void LLNotifications::addChannel(LLNotificationChannelPtr pChan)
{
	mChannels[pChan->getName()] = pChan;
}

LLNotificationChannelPtr LLNotifications::getChannel(const std::string& channelName)
{
	ChannelMap::iterator p = mChannels.find(channelName);
	if(p == mChannels.end())
	{
		llerrs << "Did not find channel named " << channelName << llendl;
	}
	return p->second;
}


// this function is called once at construction time, after the object is constructed.
void LLNotifications::initSingleton()
{
	loadTemplates();
	createDefaultChannels();
}

void LLNotifications::createDefaultChannels()
{
	// now construct the various channels AFTER loading the notifications,
	// because the history channel is going to rewrite the stored notifications file
	LLNotificationChannel::buildChannel("Expiration", "",
		boost::bind(&LLNotifications::expirationFilter, this, _1));
	LLNotificationChannel::buildChannel("Unexpired", "",
		!boost::bind(&LLNotifications::expirationFilter, this, _1)); // use negated bind
	LLNotificationChannel::buildChannel("Unique", "Unexpired",
		boost::bind(&LLNotifications::uniqueFilter, this, _1));
	LLNotificationChannel::buildChannel("Ignore", "Unique",
		filterIgnoredNotifications);
	LLNotificationChannel::buildChannel("Visible", "Ignore",
		&LLNotificationFilters::includeEverything);

	// create special history channel
	//std::string notifications_log_file = gDirUtilp->getExpandedFilename ( LL_PATH_PER_SL_ACCOUNT, "open_notifications.xml" );
	// use ^^^ when done debugging notifications serialization
	std::string notifications_log_file = gDirUtilp->getExpandedFilename ( LL_PATH_USER_SETTINGS, "open_notifications.xml" );
	// this isn't a leak, don't worry about the empty "new"
	new LLNotificationHistoryChannel(notifications_log_file);

	// connect action methods to these channels
	LLNotifications::instance().getChannel("Expiration")->
		connectChanged(boost::bind(&LLNotifications::expirationHandler, this, _1));
	LLNotifications::instance().getChannel("Unique")->
		connectChanged(boost::bind(&LLNotifications::uniqueHandler, this, _1));
	LLNotifications::instance().getChannel("Unique")->
		connectFailedFilter(boost::bind(&LLNotifications::failedUniquenessTest, this, _1));
	LLNotifications::instance().getChannel("Ignore")->
		connectFailedFilter(&handleIgnoredNotification);
}

static std::string sStringSkipNextTime("Skip this dialog next time");
static std::string sStringAlwaysChoose("Always choose this option");

bool LLNotifications::addTemplate(const std::string &name, 
								  LLNotificationTemplatePtr theTemplate)
{
	if (mTemplates.count(name))
	{
		llwarns << "LLNotifications -- attempted to add template '" << name << "' twice." << llendl;
		return false;
	}
	mTemplates[name] = theTemplate;
	return true;
}

LLNotificationTemplatePtr LLNotifications::getTemplate(const std::string& name)
{
	if (mTemplates.count(name))
	{
		return mTemplates[name];
	}
	else
	{
		return mTemplates["MissingAlert"];
	}
}

bool LLNotifications::templateExists(const std::string& name)
{
	return (mTemplates.count(name) != 0);
}

void LLNotifications::clearTemplates()
{
	mTemplates.clear();
}

void LLNotifications::forceResponse(const LLNotification::Params& params, S32 option)
{
	LLNotificationPtr temp_notify(new LLNotification(params));
	LLSD response = temp_notify->getResponseTemplate();
	LLSD selected_item = temp_notify->getForm()->getElement(option);
	
	if (selected_item.isUndefined())
	{
		llwarns << "Invalid option" << option << " for notification " << (std::string)params.name << llendl;
		return;
	}
	response[selected_item["name"].asString()] = true;

	temp_notify->respond(response);
}

LLNotifications::TemplateNames LLNotifications::getTemplateNames() const
{
	TemplateNames names;
	for (TemplateMap::const_iterator it = mTemplates.begin(); it != mTemplates.end(); ++it)
	{
		names.push_back(it->first);
	}
	return names;
}

typedef std::map<std::string, std::string> StringMap;
void replaceSubstitutionStrings(LLXMLNodePtr node, StringMap& replacements)
{
	//llwarns << "replaceSubstitutionStrings" << llendl;
	// walk the list of attributes looking for replacements
	for (LLXMLAttribList::iterator it=node->mAttributes.begin();
		 it != node->mAttributes.end(); ++it)
	{
		std::string value = it->second->getValue();
		if (value[0] == '$')
		{
			value.erase(0, 1);	// trim off the $
			std::string replacement;
			StringMap::const_iterator found = replacements.find(value);
			if (found != replacements.end())
			{
				replacement = found->second;
				//llwarns << "replaceSubstituionStrings: value: " << value << " repl: " << replacement << llendl;

				it->second->setValue(replacement);
			}
			else
			{
				llwarns << "replaceSubstituionStrings FAILURE: value: " << value << " repl: " << replacement << llendl;
			}
		}
	}
	
	// now walk the list of children and call this recursively.
	for (LLXMLNodePtr child = node->getFirstChild(); 
		 child.notNull(); child = child->getNextSibling())
	{
		replaceSubstitutionStrings(child, replacements);
	}
}

// private to this file
// returns true if the template request was invalid and there's nothing else we
// can do with this node, false if you should keep processing (it may have
// replaced the contents of the node referred to)
LLXMLNodePtr LLNotifications::checkForXMLTemplate(LLXMLNodePtr item)
{
	if (item->hasName("usetemplate"))
	{
		std::string replacementName;
		if (item->getAttributeString("name", replacementName))
		{
			StringMap replacements;
			for (LLXMLAttribList::const_iterator it=item->mAttributes.begin(); 
				 it != item->mAttributes.end(); ++it)
			{
				replacements[it->second->getName()->mString] = it->second->getValue();
			}
			if (mXmlTemplates.count(replacementName))
			{
				item=LLXMLNode::replaceNode(item, mXmlTemplates[replacementName]);
				
				// walk the nodes looking for $(substitution) here and replace
				replaceSubstitutionStrings(item, replacements);
			}
			else
			{
				llwarns << "XML template lookup failure on '" << replacementName << "' " << llendl;
			}
		}
	}
	return item;
}

bool LLNotifications::loadTemplates()
{
	const std::string xml_filename = "notifications.xml";
	LLXMLNodePtr root;
	
	BOOL success  = LLUICtrlFactory::getLayeredXMLNode(xml_filename, root);
	
	if (!success || root.isNull() || !root->hasName( "notifications" ))
	{
		llerrs << "Problem reading UI Notifications file: " << xml_filename << llendl;
		return false;
	}
	
	clearTemplates();
	
	for (LLXMLNodePtr item = root->getFirstChild();
		 item.notNull(); item = item->getNextSibling())
	{
		// we do this FIRST so that item can be changed if we 
		// encounter a usetemplate -- we just replace the
		// current xml node and keep processing
		item = checkForXMLTemplate(item);
		
		if (item->hasName("global"))
		{
			std::string global_name;
			if (item->getAttributeString("name", global_name))
			{
				mGlobalStrings[global_name] = item->getTextContents();
			}
			continue;
		}
		
		if (item->hasName("template"))
		{
			// store an xml template; templates must have a single node (can contain
			// other nodes)
			std::string name;
			item->getAttributeString("name", name);
			LLXMLNodePtr ptr = item->getFirstChild();
			mXmlTemplates[name] = ptr;
			continue;
		}
		
		if (!item->hasName("notification"))
		{
            llwarns << "Unexpected entity " << item->getName()->mString << 
                       " found in " << xml_filename << llendl;
			continue;
		}
		
		// now we know we have a notification entry, so let's build it
		LLNotificationTemplatePtr pTemplate(new LLNotificationTemplate());

		if (!item->getAttributeString("name", pTemplate->mName))
		{
			llwarns << "Unable to parse notification with no name" << llendl;
			continue;
		}
		
		//llinfos << "Parsing " << pTemplate->mName << llendl;
		
		pTemplate->mMessage = item->getTextContents();
		pTemplate->mDefaultFunctor = pTemplate->mName;
		item->getAttributeString("type", pTemplate->mType);
		item->getAttributeString("icon", pTemplate->mIcon);
		item->getAttributeString("label", pTemplate->mLabel);
		item->getAttributeU32("duration", pTemplate->mExpireSeconds);
		item->getAttributeU32("expireOption", pTemplate->mExpireOption);

		std::string priority;
		item->getAttributeString("priority", priority);
		pTemplate->mPriority = NOTIFICATION_PRIORITY_NORMAL;
		if (!priority.empty())
		{
			if (priority == "low")      pTemplate->mPriority = NOTIFICATION_PRIORITY_LOW;
			if (priority == "normal")   pTemplate->mPriority = NOTIFICATION_PRIORITY_NORMAL;
			if (priority == "high")     pTemplate->mPriority = NOTIFICATION_PRIORITY_HIGH;
			if (priority == "critical") pTemplate->mPriority = NOTIFICATION_PRIORITY_CRITICAL;
		}
		
		item->getAttributeString("functor", pTemplate->mDefaultFunctor);

		BOOL persist = false;
		item->getAttributeBOOL("persist", persist);
		pTemplate->mPersist = persist;
		
		std::string sound;
		item->getAttributeString("sound", sound);
		if (!sound.empty())
		{
			// TODO: test for bad sound effect name / missing effect
			pTemplate->mSoundEffect = LLUUID(LLUI::sConfigGroup->getString(sound.c_str()));
		}

		for (LLXMLNodePtr child = item->getFirstChild();
			 !child.isNull(); child = child->getNextSibling())
		{
			child = checkForXMLTemplate(child);
			
			// <url>
			if (child->hasName("url"))
			{
				pTemplate->mURL = child->getTextContents();
				child->getAttributeU32("option", pTemplate->mURLOption);
			}
			
            if (child->hasName("unique"))
            {
                pTemplate->mUnique = true;
                for (LLXMLNodePtr formitem = child->getFirstChild();
                     !formitem.isNull(); formitem = formitem->getNextSibling())
                {
                    if (formitem->hasName("context"))
                    {
                        std::string key;
                        formitem->getAttributeString("key", key);
                        pTemplate->mUniqueContext.push_back(key);
                        //llwarns << "adding " << key << " to unique context" << llendl;
                    }
                    else
                    {
                        llwarns << "'unique' has unrecognized subelement " 
                        << formitem->getName()->mString << llendl;
                    }
                }
            }
            
			// <form>
			if (child->hasName("form"))
			{
                pTemplate->mForm = LLNotificationFormPtr(new LLNotificationForm(pTemplate->mName, child));
			}
		}
		addTemplate(pTemplate->mName, pTemplate);
	}
	
	//std::ostringstream ostream;
	//root->writeToOstream(ostream, "\n  ");
	//llwarns << ostream.str() << llendl;
	
	return true;
}

// we provide a couple of simple add notification functions so that it's reasonable to create notifications in one line
LLNotificationPtr LLNotifications::add(const std::string& name, 
										const LLSD& substitutions, 
										const LLSD& payload)
{
	return add(LLNotification::Params(name).substitutions(substitutions).payload(payload));	
}

LLNotificationPtr LLNotifications::add(const std::string& name, 
										const LLSD& substitutions, 
										const LLSD& payload, 
										const std::string& functor_name)
{
	return add(LLNotification::Params(name).substitutions(substitutions).payload(payload).functor_name(functor_name));	
}

LLNotificationPtr LLNotifications::add(const std::string& name, 
										const LLSD& substitutions, 
										const LLSD& payload, 
										LLNotificationFunctorRegistry::ResponseFunctor functor)
{
	return add(LLNotification::Params(name).substitutions(substitutions).payload(payload).functor(functor));	
}

// generalized add function that takes a parameter block object for more complex instantiations
LLNotificationPtr LLNotifications::add(const LLNotification::Params& p)
{
	LLNotificationPtr pNotif(new LLNotification(p));
	add(pNotif);
	return pNotif;
}


void LLNotifications::add(const LLNotificationPtr pNotif)
{
	// first see if we already have it -- if so, that's a problem
	LLNotificationSet::iterator it=mItems.find(pNotif);
	if (it != mItems.end())
	{
		llerrs << "Notification added a second time to the master notification channel." << llendl;
	}

	updateItem(LLSD().insert("sigtype", "add").insert("id", pNotif->id()), pNotif);
}

void LLNotifications::cancel(LLNotificationPtr pNotif)
{
	LLNotificationSet::iterator it=mItems.find(pNotif);
	if (it == mItems.end())
	{
		llerrs << "Attempted to delete nonexistent notification " << pNotif->getName() << llendl;
	}
	updateItem(LLSD().insert("sigtype", "delete").insert("id", pNotif->id()), pNotif);
	pNotif->cancel();
}

void LLNotifications::update(const LLNotificationPtr pNotif)
{
	LLNotificationSet::iterator it=mItems.find(pNotif);
	if (it != mItems.end())
	{
		updateItem(LLSD().insert("sigtype", "change").insert("id", pNotif->id()), pNotif);
	}
}


LLNotificationPtr LLNotifications::find(LLUUID uuid)
{
	LLNotificationPtr target = LLNotificationPtr(new LLNotification(uuid));
	LLNotificationSet::iterator it=mItems.find(target);
	if (it == mItems.end())
	{
		llwarns << "Tried to dereference uuid '" << uuid << "' as a notification key but didn't find it." << llendl;
		return LLNotificationPtr((LLNotification*)NULL);
	}
	else
	{
		return *it;
	}
}

void LLNotifications::forEachNotification(NotificationProcess process)
{
	std::for_each(mItems.begin(), mItems.end(), process);
}

std::string LLNotifications::getGlobalString(const std::string& key) const
{
	GlobalStringMap::const_iterator it = mGlobalStrings.find(key);
	if (it != mGlobalStrings.end())
	{
		return it->second;
	}
	else
	{
		// if we don't have the key as a global, return the key itself so that the error
		// is self-diagnosing.
		return key;
	}
}

													
// ---
// END OF LLNotifications implementation
// =========================================================

std::ostream& operator<<(std::ostream& s, const LLNotification& notification)
{
	s << notification.summarize();
	return s;
}