var API3 = function(m)
{

// Shared script handling templates and basic terrain analysis
m.SharedScript = function(settings)
{
	if (!settings)
		return;
	
	this._players = settings.players;
	this._templates = settings.templates;
	this._derivedTemplates = {};
	this._techTemplates = settings.techTemplates;
		
	this._entityMetadata = {};
	for (var i in this._players)
		this._entityMetadata[this._players[i]] = {};

	// always create for 8 + gaia players, since _players isn't aware of the human.
	this._techModifications = { 0 : {}, 1 : {}, 2 : {}, 3 : {}, 4 : {}, 5 : {}, 6 : {}, 7 : {}, 8 : {} };
	
	// array of entity collections
	this._entityCollections = [];
	// each name is a reference to the actual one.
	this._entityCollectionsName = {};
	this._entityCollectionsByDynProp = {};
	this._entityCollectionsUID = 0;
	
	// A few notes about these maps. They're updated by checking for "create" and "destroy" events for all resources
	// TODO: change the map when the resource amounts change for at least stone and metal mines.
	this.resourceMaps = {}; // Contains maps showing the density of wood, stone and metal
	this.CCResourceMaps = {}; // Contains maps showing the density of wood, stone and metal, optimized for CC placement.
	// Resource maps data.
	// By how much to divide the resource amount for plotting (ie a tree having 200 wood is "4").
	this.decreaseFactor = {'wood': 50.0, 'stone': 90.0, 'metal': 90.0, 'food': 40.0};

	this.turn = 0;
}

//Return a simple object (using no classes etc) that will be serialized
//into saved games
//TODO: that
m.SharedScript.prototype.Serialize = function()
{
	return { "players" : this._players, "templates" : this._templates, "techTp" : this._techTemplates };
};

// Called after the constructor when loading a saved game, with 'data' being
// whatever Serialize() returned
m.SharedScript.prototype.Deserialize = function(data)
{
	this._players = data.players;
	this._templates = data.templates;
	this._techTemplates = data.techTp;
	this.isDeserialized = true;
};

// Components that will be disabled in foundation entity templates.
// (This is a bit yucky and fragile since it's the inverse of
// CCmpTemplateManager::CopyFoundationSubset and only includes components
// that our Template class currently uses.)
m.g_FoundationForbiddenComponents = {
	"ProductionQueue": 1,
	"ResourceSupply": 1,
	"ResourceDropsite": 1,
	"GarrisonHolder": 1,
};

// Components that will be disabled in resource entity templates.
// Roughly the inverse of CCmpTemplateManager::CopyResourceSubset.
m.g_ResourceForbiddenComponents = {
	"Cost": 1,
	"Decay": 1,
	"Health": 1,
	"UnitAI": 1,
	"UnitMotion": 1,
	"Vision": 1
};

m.SharedScript.prototype.GetTemplate = function(name)
{	
	if (this._templates[name])
		return this._templates[name];
	
	if (this._derivedTemplates[name])
		return this._derivedTemplates[name];
	
	// If this is a foundation template, construct it automatically
	if (name.indexOf("foundation|") !== -1)
	{
		var base = this.GetTemplate(name.substr(11));
		
		var foundation = {};
		for (var key in base)
			if (!m.g_FoundationForbiddenComponents[key])
				foundation[key] = base[key];
		
		this._derivedTemplates[name] = foundation;
		return foundation;
	}
	else if (name.indexOf("resource|") !== -1)
	{
		var base = this.GetTemplate(name.substr(9));
		
		var resource = {};
		for (var key in base)
			if (!m.g_ResourceForbiddenComponents[key])
				resource[key] = base[key];
		
		this._derivedTemplates[name] = resource;
		return resource;
	}
	
	error("Tried to retrieve invalid template '"+name+"'");
	return null;
};

// Initialize the shared component.
// We need to now the initial state of the game for this, as we will use it.
// This is called right at the end of the map generation.
m.SharedScript.prototype.init = function(state) {
	this.ApplyTemplatesDelta(state);

	this.passabilityClasses = state.passabilityClasses;
	this.passabilityMap = state.passabilityMap;
	this.players = this._players;
	this.playersData = state.players;
	this.territoryMap = state.territoryMap;
	this.timeElapsed = state.timeElapsed;
	this.barterPrices = state.barterPrices;

	this._entities = {};
	for (var id in state.entities)
	{
		// entropy generator
		for (var p = 0; p < id; ++p)
			Math.random();
		this._entities[id] = new m.Entity(this, state.entities[id]);
	}
	// entity collection updated on create/destroy event.
	this.entities = new m.EntityCollection(this, this._entities);
	
	// create the terrain analyzer
	this.terrainAnalyzer = new m.TerrainAnalysis();
	this.terrainAnalyzer.init(this, state);
	this.accessibility = new m.Accessibility();
	this.accessibility.init(state, this.terrainAnalyzer);
	
	// defined in TerrainAnalysis.js
	this.createResourceMaps(this);

	this.gameState = {};
	for (var i in this._players)
	{
		this.gameState[this._players[i]] = new m.GameState();
		this.gameState[this._players[i]].init(this,state,this._players[i]);
	}
};

// General update of the shared script, before each AI's update
// applies entity deltas, and each gamestate.
m.SharedScript.prototype.onUpdate = function(state)
{
	if (this.isDeserialized && this.turn !== 0)
	{
		this.isDeserialized = false;
		this.init(state);
	} else if (this.isDeserialized)
		return;
	// deals with updating based on create and destroy messages.
	this.ApplyEntitiesDelta(state);
	this.ApplyTemplatesDelta(state);

	Engine.ProfileStart("onUpdate");

	// those are dynamic and need to be reset as the "state" object moves in memory.
	this.events = state.events;
	this.passabilityClasses = state.passabilityClasses;
	this.passabilityMap = state.passabilityMap;
	this.playersData = state.players;
	this.territoryMap = state.territoryMap;
	this.timeElapsed = state.timeElapsed;
	this.barterPrices = state.barterPrices;
	
	for (var i in this.gameState)
		this.gameState[i].update(this,state);

	// TODO: merge those two with "ApplyEntitiesDelta" since after all they do the same.
	this.updateResourceMaps(this, this.events);
	this.terrainAnalyzer.updateMapWithEvents(this);
	
	this.turn++;
	
	Engine.ProfileStop();
};

m.SharedScript.prototype.ApplyEntitiesDelta = function(state)
{
	Engine.ProfileStart("Shared ApplyEntitiesDelta");

	var foundationFinished = {};
	
	// by order of updating:
	// we "Destroy" last because we want to be able to switch Metadata first.
	var CreateEvents = state.events["Create"];
	var DestroyEvents = state.events["Destroy"];
	var RenamingEvents = state.events["EntityRenamed"];
	var TrainingEvents = state.events["TrainingFinished"];
	var ConstructionEvents = state.events["ConstructionFinished"];
	var MetadataEvents = state.events["AIMetadata"];
	var ownershipChangeEvents = state.events["OwnershipChanged"];

	for (var i = 0; i < CreateEvents.length; ++i)
	{
		var evt = CreateEvents[i];
		if (!state.entities[evt.entity])
			continue; // Sometimes there are things like foundations which get destroyed too fast

		this._entities[evt.entity] = new m.Entity(this, state.entities[evt.entity]);
		this.entities.addEnt(this._entities[evt.entity]);
		
		// Update all the entity collections since the create operation affects static properties as well as dynamic
		for (var entCollection in this._entityCollections)
			this._entityCollections[entCollection].updateEnt(this._entities[evt.entity]);
	}
	for (var i in RenamingEvents)
	{
		var evt = RenamingEvents[i];
		// Switch the metadata
		for (var p in this._players)
		{
			this._entityMetadata[this._players[p]][evt.newentity] = this._entityMetadata[this._players[p]][evt.entity];
			this._entityMetadata[this._players[p]][evt.entity] = {};
		}
	}
	for (var i in TrainingEvents)
	{
		var evt = TrainingEvents[i];
		// Apply metadata stored in training queues
		for each (var ent in evt.entities)
		{
			for (var key in evt.metadata)
			{
				this.setMetadata(evt.owner, this._entities[ent], key, evt.metadata[key])
			}
		}
	}
	for (var i in ConstructionEvents)
	{
		var evt = ConstructionEvents[i];
		// we'll move metadata.
		if (!this._entities[evt.entity])
			continue;
		var ent = this._entities[evt.entity];
		var newEnt = this._entities[evt.newentity];
		if (this._entityMetadata[ent.owner()] && this._entityMetadata[ent.owner()][evt.entity] !== undefined)
			for (var key in this._entityMetadata[ent.owner()][evt.entity])
			{
				this.setMetadata(ent.owner(), newEnt, key, this._entityMetadata[ent.owner()][evt.entity][key])
			}
		foundationFinished[evt.entity] = true;
	}
	for (var i in MetadataEvents)
	{
		var evt = MetadataEvents[i];
		if (!this._entities[evt.id])
			continue;	// might happen in some rare cases of foundations getting destroyed, perhaps.
						// Apply metadata (here for buildings for example)
		for (var key in evt.metadata)
		{
			this.setMetadata(evt.owner, this._entities[evt.id], key, evt.metadata[key])
		}
	}
	
	for (var i = 0; i < DestroyEvents.length; ++i)
	{
		var evt = DestroyEvents[i];
		// A small warning: javascript "delete" does not actually delete, it only removes the reference in this object.
		// the "deleted" object remains in memory, and any older reference to it will still reference it as if it were not "deleted".
		// Worse, they might prevent it from being garbage collected, thus making it stay alive and consuming ram needlessly.
		// So take care, and if you encounter a weird bug with deletion not appearing to work correctly, this is probably why.
		if (!this._entities[evt.entity])
			continue;// probably should remove the event.

		if (foundationFinished[evt.entity])
			evt["SuccessfulFoundation"] = true;
		
		// The entity was destroyed but its data may still be useful, so
		// remember the entity and this AI's metadata concerning it
		evt.metadata = {};
		evt.entityObj = this._entities[evt.entity];
		for (var j in this._players)
			evt.metadata[this._players[j]] = this._entityMetadata[this._players[j]][evt.entity];
		
		for each (var entCol in this._entityCollections)
		{
			entCol.removeEnt(this._entities[evt.entity]);
		}
		this.entities.removeEnt(this._entities[evt.entity]);
		
		delete this._entities[evt.entity];
		for (var j in this._players)
			delete this._entityMetadata[this._players[j]][evt.entity];
	}

	for (var id in state.entities)
	{
		var changes = state.entities[id];

		for (var prop in changes)
		{
			this._entities[id]._entity[prop] = changes[prop];
			
			this.updateEntityCollections(prop, this._entities[id]);
		}
	}

	// apply per-entity aura-related changes.
	// this supersedes tech-related changes.
	for (var id in state.changedEntityTemplateInfo)
	{
		if (!this._entities[id])
			continue;	// dead, presumably.
		var changes = state.changedEntityTemplateInfo[id];
		for each (var change in changes)
			this._entities[id]._auraTemplateModif[change.variable] = change.value;
	}
	Engine.ProfileStop();
};

m.SharedScript.prototype.ApplyTemplatesDelta = function(state)
{
	Engine.ProfileStart("Shared ApplyTemplatesDelta");

	for (var player in state.changedTemplateInfo)
	{
		var playerDiff = state.changedTemplateInfo[player];
		for (var template in playerDiff)
		{
			var changes = playerDiff[template];
			if (!this._techModifications[player][template])
				this._techModifications[player][template] = {};
			for each (var change in changes)
				this._techModifications[player][template][change.variable] = change.value;
		}
	}
	Engine.ProfileStop();
};

m.SharedScript.prototype.registerUpdatingEntityCollection = function(entCollection, noPush)
{
	if (!noPush) {
		this._entityCollections.push(entCollection);
	}
	entCollection.setUID(this._entityCollectionsUID);
	for each (var prop in entCollection.dynamicProperties())
	{
		this._entityCollectionsByDynProp[prop] = this._entityCollectionsByDynProp[prop] || [];
		this._entityCollectionsByDynProp[prop].push(entCollection);
	}
	this._entityCollectionsUID++;
};

m.SharedScript.prototype.removeUpdatingEntityCollection = function(entCollection)
{
	for (var i in this._entityCollections)
	{
		if (this._entityCollections[i].getUID() === entCollection.getUID())
		{
			this._entityCollections.splice(i, 1);
		}
	}
	
	for each (var prop in entCollection.dynamicProperties())
	{
		for (var i in this._entityCollectionsByDynProp[prop])
		{
			if (this._entityCollectionsByDynProp[prop][i].getUID() === entCollection.getUID())
			{
				this._entityCollectionsByDynProp[prop].splice(i, 1);
			}
		}
	}
};

m.SharedScript.prototype.updateEntityCollections = function(property, ent)
{
	if (this._entityCollectionsByDynProp[property] !== undefined)
	{
		for (var entCollectionid in this._entityCollectionsByDynProp[property])
		{
			this._entityCollectionsByDynProp[property][entCollectionid].updateEnt(ent);
		}
	}
}

m.SharedScript.prototype.setMetadata = function(player, ent, key, value)
{
	var metadata = this._entityMetadata[player][ent.id()];
	if (!metadata)
		metadata = this._entityMetadata[player][ent.id()] = {};
	metadata[key] = value;
	
	this.updateEntityCollections('metadata', ent);
	this.updateEntityCollections('metadata.' + key, ent);
};
m.SharedScript.prototype.getMetadata = function(player, ent, key)
{
	var metadata = this._entityMetadata[player][ent.id()];
	
	if (!metadata || !(key in metadata))
		return undefined;
	return metadata[key];
};
m.SharedScript.prototype.deleteMetadata = function(player, ent, key)
{
	var metadata = this._entityMetadata[player][ent.id()];
	
	if (!metadata || !(key in metadata))
		return true;
	metadata[key] = undefined;
	delete metadata[key];
	return true;
};

m.copyPrototype = function(descendant, parent) {
    var sConstructor = parent.toString();
    var aMatch = sConstructor.match( /\s*function (.*)\(/ );
	if ( aMatch != null ) { descendant.prototype[aMatch[1]] = parent; }
	for (var m in parent.prototype) {
		descendant.prototype[m] = parent.prototype[m];
	}
};

return m;

}(API3);