flee.js

/**
 * Pick the closest portal. If advancing to it puts you in danger, pick the less dangerous portal instead. If it's the same, or it 
 * still endangers you, there's no escape portal 
 */

Enemy.prototype.getEscapePortal = function(){
	console.log('getEscapePortal');
	var portal = this.getClosestPortal();
	if (!portal){
		console.log('no closest portal');
		return false;
	}
	if (this.isDangerousPosition(portal)){
		console.log('closest portal at ('+portal.x+','+portal.y+') is dangerous');
		var lessDangerousPortal = this.getLessDangerousPortal();
		if (!lessDangerousPortal || lessDangerousPortal == portal){
			console.log('and is the same as the less dangerous portal');
			return false;
		}
		console.log('heading to less dangerous portal at ('+lessDangerousPortal.x+','+lessDangerousPortal.y+')');
		return lessDangerousPortal;
	} else {
		console.log('using closest portal at ('+portal.x+','+portal.y+')');
		return portal;
	}
}

// Check if there are enemies around this position
Enemy.prototype.isDangerousPosition = function(position){
	for(var j = 0; j < this.currentRoom.monsters.length; j++){
		var monster = this.currentRoom.monsters[j];
		if (monster == this)
			continue;
		if (monster.isFriendly != this.isFriendly){
			var xDiff = Math.abs(monster.x - position.x);
    			var yDiff = Math.abs(monster.y - position.y);
    			if (xDiff <= 1 && yDiff <= 1){
				return true;
    			}
		}
	}
	if (!this.isFriendly){
		var xDiff = Math.abs(this.gameController.player.x - position.x);
		var yDiff = Math.abs(this.gameController.player.y - position.y);
		if (xDiff <= 1 && yDiff <= 1){
			return true;
		}
	}
	return false;
}

/**
 * Pick the nearest portal
 * Special case: If not friendly, calculate how close the player is and discard if player is closer than I
  */

Enemy.prototype.getClosestPortal = function(){
	var minDistance = 9999;
	var nearPortal = false;
	for (var i = 0; i < this.currentRoom.portals.length; i++){
		var portal = this.currentRoom.portals[i];
		var myDistance = flatDistance(portal.x, portal.y, this.x, this.y);
		if (!this.isFriendly){
			var playerDistance = flatDistance(portal.x, portal.y, this.gameController.player.x, this.gameController.player.y);
			if (playerDistance < myDistance)
				continue;
		}
		if (myDistance < minDistance){
			minDistance = myDistance;
			nearPortal = portal;
		}
	}
	return nearPortal;
}

function lowerDanger(a, b){
	return b.danger - a.danger;
}
Enemy.prototype.getLessDangerousPortal = function(){
	if (this.currentRoom.portals.length == 1){
		return this.currentRoom.portals[0];
	}
	var portalsDanger = [];
	for (var i = 0; i < this.currentRoom.portals.length; i++){
		var portal = this.currentRoom.portals[i];
		// Sum the distance of all enemies to the portal
		var sum = 0;
		for(var j = 0; j < this.currentRoom.monsters.length; j++){
			var monster = this.currentRoom.monsters[j];
			if (monster.isFriendly != this.isFriendly){
				sum += flatDistance(portal.x, portal.y, monster.x, monster.y);
			}
		}
		if (!this.isFriendly){
			sum += flatDistance(portal.x, portal.y, this.gameController.player.x, this.gameController.player.y);
		}
		portalsDanger.push({portal: portal, danger: sum});
	}
	portalsDanger.sort(lowerDanger);
	return portalsDanger[0].portal;
}