roleHarvester = function(creep) {

    if(creep.carry.energy < creep.carryCapacity) {
        let sources = creep.room.find(FIND_SOURCES)
        if(creep.harvest(sources[0]) == ERR_NOT_IN_RANGE) {
            creep.moveTo(sources[0]);
        }
    }
    else {
        let targets = creep.pos.findClosestByPath(FIND_STRUCTURES, {
                filter: (structure) =>
                            (structure.structureType == STRUCTURE_SPAWN && structure.energy < structure.energyCapacity ) ||
                            (structure.structureType == STRUCTURE_EXTENSION && structure.energy < structure.energyCapacity ) ||
                            (structure.structureType == STRUCTURE_CONTAINER && structure.store.energy < structure.storeCapacity )

        })
        if(targets) {
            if(creep.transfer(targets, RESOURCE_ENERGY) == ERR_NOT_IN_RANGE) {
                creep.moveTo(targets);
            }
        }

        else {
             if(creep.memory.building) {
	        let targets = creep.room.find(FIND_CONSTRUCTION_SITES);
	        let rtargets = creep.room.find(FIND_STRUCTURES, {
	            filter: (structure) => structure.hits < structure.hitsMax && structure.hits < 100000
	        });

	        if(targets.length) {
	            if(creep.build(targets[0]) == ERR_NOT_IN_RANGE) {
	                creep.moveTo(targets[0]);
	            }
	        }
	        else if(rtargets.length) {
	            if(creep.repair(rtargets[0]) == ERR_NOT_IN_RANGE) {
	                creep.moveTo(rtargets[0]);
	            }
	    }
	    }

        }
    }

}